WO2025175561A1

WO2025175561A1 - Frequency drift reporting

Info

Publication number: WO2025175561A1
Application number: PCT/CN2024/078336
Authority: WO
Inventors: Siyi Chen; Shaozhen GUO; Mostafa KHOSHNEVISAN; Xiaoxia Zhang; Jing Sun; Changlong Xu; Luanxia YANG; Hao Xu; Jing Dai
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2024-02-23
Filing date: 2024-02-23
Publication date: 2025-08-28
Anticipated expiration: 2026-08-23

Abstract

Various aspects of the present disclosure generally relate to wireless communication. Some aspects relate generally to frequency drift reporting. Some aspects more specifically relate to a channel state information (CSI) configuration to enable a user equipment (UE) to transmit an indication of frequency drift values to a network node. In some aspects, the CSI configuration may indicate one or more CSI reference signal (CSI-RS) resource sets that are configured for the UE to measure or estimate frequency drifts. For example, the CSI-RS resource sets may be associated with respective transmission reception points (TRPs) in a multi-TRP deployment. In some aspects, the CSI configuration may include a report quantity parameter that indicates that the CSI configuration is associated with frequency drift reporting.

Description

FREQUENCY DRIFT REPORTING

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and specifically relate to techniques, apparatuses, and methods associated with frequency drift reporting.

BACKGROUND

Wireless communication systems are widely deployed to provide various services that may include carrying voice, text, messaging, video, data, and/or other traffic. The services may include unicast, multicast, and/or broadcast services, among other examples. Typical wireless communication systems may employ multiple-access radio access technologies (RATs) capable of supporting communication with multiple users by sharing available system resources (for example, time domain resources, frequency domain resources, spatial domain resources, and/or device transmit power, among other examples) . Examples of such multiple-access RATs include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.

The above multiple-access RATs have been adopted in various telecommunication standards to provide common protocols that enable different wireless communication devices to communicate on a municipal, national, regional, or global level. An example telecommunication standard is New Radio (NR) . NR, which may also be referred to as 5G, is part of a continuous mobile broadband evolution promulgated by the Third Generation Partnership Project (3GPP) . NR (and other mobile broadband evolutions beyond NR) may be designed to better support Internet of things (IoT) and reduced capability device deployments, industrial connectivity, millimeter wave (mmWave) expansion, licensed and unlicensed spectrum access, non-terrestrial network (NTN) deployment, sidelink and other device-to-device direct communication technologies (for example, cellular vehicle-to-everything (CV2X) communication) , massive multiple-input multiple-output (MIMO) , disaggregated network architectures and network topology expansions, multiple-subscriber implementations, high-precision positioning, and/or radio frequency (RF) sensing, among other examples. As the demand for mobile broadband access continues to increase, further improvements in NR may be implemented, and other radio access technologies such as 6G may be introduced, to further advance mobile broadband evolution.

Coherent joint transmission (CJT) may involve multiple transmitters (for example, multiple transmission reception points (TRPs) ) that each transmit a communication with a phase that is constructively combined at a receiver (for example, at a user equipment (UE) ) . CJT may include beamforming with antennas that are not co-located and/or that correspond to different TRPs. CJT may improve the signal power and spatial diversity of communications in a wireless communication network. A CJT may be achieved when phase synchronization across the multiple TRPs is possible (for example, when the multiple TRPs are driven by a same clock, when antenna ports of the multiple TRPs are quasi co-located, and/or in other scenarios) , thereby enabling a joint precoder design to be used by the multiple TRPs.

To optimize performance of CJTs, a network node may perform one or more operations to ensure a phase coherence between TRPs in a CJT multi-TRP scenario. For example, phase coherence between multiple TRPs may improve the likelihood of signals transmitted by the multiple TRPs being aligned in phase when combined at a UE, thereby improving constructive interference and a signal-to-noise ratio (SNR) of the received signals at the UE. For example, if phase is not synchronized among the multiple TRPs, signals from different TRPs may introduce destructive interference when combined at the UE, resulting in signal degradation and/or degraded performance. Phase coherence among multiple TRPs in a CJT multi-TRP scenario may enable efficient signal combining (for example, coherent signal combining at the UE) , improved beamforming, improved interference mitigation, and/or more reliable communications, among other examples.

However, in CJT multi-TRP deployments, phase synchronization among multiple TRPs may be difficult. For example, the multiple TRPs may use different clocks (for example, resulting in timing misalignment between the multiple TRPs) , and/or antenna panels of the multiple TRPs may not be co-located (for example, the antenna panels may be at different locations or mounted on different devices) , among other examples. Therefore, a network node may compensate for differences in phase among the multiple TRPs to improve phase synchronization among the multiple TRPs. However, phase variation between two (or more) TRPs may vary over time (for example, because of varying UE velocity and/or clock drift) . In other words, a difference in phase between two (or more) TRPs may not be linear over time (for example, an amount by which the phase varies over time may change) . Such phase variation (for example, that is not linear over time) may be compensated for by using a frequency drift (for example, an unintended change in a frequency of signals transmitted via a given TRP over time) . For example, the network node may use a frequency drift to track and/or compensate for phase variations, such as by using the frequency drift in one or more adaptative processing operations (for example, an equalization operation) .

Therefore, to improve a likelihood of phase coherence in a CJT multi-TRP scenario, a network node may obtain measurements or estimates of a frequency drift over time. For example, a single measurement of frequency drift may be insufficient to ensure phase synchronization because an amount by which phase varies for a given TRP (for example, as received at the UE) may not be linear over time. In some examples, such as in time division duplexing (TDD) deployments, the network node may estimate the frequency drift by measuring an uplink channel of respective TRPs and by using channel reciprocity (for example, because an uplink channel and a downlink channel may use the same frequency resources (for example, the same subband) in TDD deployments) . However, in other examples, the network node may be unable to estimate the frequency drift at the UE, such as in frequency division duplexing (FDD) deployments (for example, because an uplink channel and a downlink channel may use different frequency resources (for example, different subbands) in FDD deployments) .

A UE may be capable of measuring and/or estimating frequency drift of a given TRP by measuring signals (for example, reference signals) that are transmitted by the given TRP. However, there are currently no mechanisms defined for measuring and/or reporting frequency drift from a UE to a network node. For example, because the UE may be unaware of the existence or deployment of TRPs included in a CJT multi-TRP deployment, the UE may be unable to identify which resources or reference signals should be measured to estimate a frequency drift for a given TRP. Therefore, the UE may misidentify a resource or reference signal to measure for estimating frequency drift of a given TRP, thereby consuming network resources, processing resources, and/or memory resources, among other examples, associated with measuring and/or estimating the frequency drift for the given TRP using the misidentified resource or reference signal. Further, the UE and the network node may not be synchronized as to a reporting mechanism for reporting frequency drifts measured or estimated by the UE. As a result, the UE may transmit an indication of a frequency drift and the network node may misidentify which TRP is associated with the frequency drift. As a result, the network node may modify a phase or precoder for a TRP using an incorrect frequency drift for the TRP, thereby degrading performance and/or reliability of a CJT in the multi-TRP scenario.

SUMMARY

Some aspects described herein relate to a user equipment (UE) for wireless communication. The UE may include a processing system that includes one or more processors and one or more memories coupled with the one or more processors. The processing system may be configured to cause the UE to receive, from a network node, a channel state information (CSI) configuration indicating multiple CSI reference signal (CSI-RS) resource sets that are configured for frequency drift reporting. The processing system may be configured to cause the UE to transmit, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

Some aspects described herein relate to a network node for wireless communication. The network node may include a processing system that includes one or more processors and one or more memories coupled with the one or more processors. The processing system may be configured to cause the network node to transmit a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The processing system may be configured to cause the network node to receive, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

Some aspects described herein relate to a method of wireless communication by a UE. The method may include receiving, from a network node, a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The method may include transmitting, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

Some aspects described herein relate to a method of wireless communication by a network node. The method may include transmitting a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The method may include receiving, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a UE. The set of instructions, when executed by one or more processors of the UE, may cause the UE to receive, from a network node, a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The set of instructions, when executed by one or more processors of the UE, may cause the UE to transmit, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a network node. The set of instructions, when executed by one or more processors of the network node, may cause the network node to transmit a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The set of instructions, when executed by one or more processors of the network node, may cause the network node to receive, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

Some aspects described herein relate to a first apparatus for wireless communication. The first apparatus may include means for receiving, from a second apparatus, a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The first apparatus may include means for transmitting, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for transmitting a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The apparatus may include means for receiving, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

Aspects of the present disclosure may generally be implemented by or as a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, network node, network entity, wireless communication device, and/or processing system as substantially described with reference to, and as illustrated by, the specification and accompanying drawings.

The foregoing paragraphs of this section have broadly summarized some aspects of the present disclosure. These and additional aspects and associated advantages will be described hereinafter. The disclosed aspects may be used as a basis for modifying or designing other aspects for carrying out the same or similar purposes of the present disclosure. Such equivalent aspects do not depart from the scope of the appended claims. Characteristics of the aspects disclosed herein, both their organization and method of operation, together with associated advantages, will be better understood from the following description when considered in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The appended drawings illustrate some aspects of the present disclosure, but are not limiting of the scope of the present disclosure because the description may enable other aspects. Each of the drawings is provided for purposes of illustration and description, and not as a definition of the limits of the claims. The same or similar reference numbers in different drawings may identify the same or similar elements.

Figure 1 is a diagram illustrating an example of a wireless communication network in accordance with the present disclosure.

Figure 2 is a diagram illustrating an example network node in communication with an example user equipment (UE) in a wireless network in accordance with the present disclosure.

Figure 3 is a diagram illustrating an example disaggregated base station architecture in accordance with the present disclosure.

Figure 4 is a diagram illustrating an example of a channel state information (CSI) report configuration in accordance with the present disclosure.

Figure 5 illustrates an example logical architecture of a distributed radio access network in accordance with the present disclosure.

Figure 6 is a diagram illustrating an example of multi-transmission reception point (TRP) communication in accordance with the present disclosure.

Figure 7 is a diagram of an example associated with frequency drift reporting in accordance with the present disclosure.

Figure 8 is a diagram of an example associated with frequency drift reporting in accordance with the present disclosure.

Figure 9 is a diagram of an example associated with frequency drift reporting in accordance with the present disclosure.

Figure 10 is a diagram of an example associated with frequency drift reporting in accordance with the present disclosure.

Figure 11 is a diagram of an example associated with a multi-part report for frequency drift reporting in accordance with the present disclosure.

Figure 12 is a diagram of an example associated with a combined report for frequency drift reporting in accordance with the present disclosure.

Figure 13 is a diagram of an example associated with aperiodic reporting for frequency drift reporting in accordance with the present disclosure.

Figure 14 is a flowchart illustrating an example process performed, for example, at a UE or an apparatus of a UE that supports frequency drift reporting in accordance with the present disclosure.

Figure 15 is a flowchart illustrating an example process performed, for example, at a network node or an apparatus of a network node that supports frequency drift reporting in accordance with the present disclosure.

Figure 16 is a diagram of an example apparatus for wireless communication that supports frequency drift reporting in accordance with the present disclosure.

Figure 17 is a diagram of an example apparatus for wireless communication that supports frequency drift reporting in accordance with the present disclosure.

DETAILED DESCRIPTION

Various aspects of the present disclosure are described hereinafter with reference to the accompanying drawings. However, aspects of the present disclosure may be embodied in many different forms and is not to be construed as limited to any specific aspect illustrated by or described with reference to an accompanying drawing or otherwise presented in this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. One skilled in the art may appreciate that the scope of the disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of or in combination with any other aspect of the disclosure. For example, an apparatus may be implemented or a method may be practiced using various combinations or quantities of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover an apparatus having, or a method that is practiced using, other structures and/or functionalities in addition to or other than the structures and/or functionalities with which various aspects of the disclosure set forth herein may be practiced. Any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim.

Several aspects of telecommunication systems will now be presented with reference to various methods, operations, apparatuses, and techniques. These methods, operations, apparatuses, and techniques will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, or algorithms (collectively referred to as “elements” ) . These elements may be implemented using hardware, software, or a combination of hardware and software. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

Various aspects relate generally to frequency drift reporting. Some aspects more specifically relate to a channel state information (CSI) configuration to enable a user equipment (UE) to transmit an indication of frequency drift values to a network node. In some aspects, the CSI configuration may indicate one or more CSI reference signal (CSI-RS) resource sets that are configured for the UE to measure or estimate frequency drifts. For example, the CSI-RS resource sets may be associated with respective transmission reception points (TRPs) in a multi-TRP deployment. In some aspects, the CSI configuration may include a report quantity parameter that indicates that the CSI configuration is associated with frequency drift reporting.

The UE may measure one or more CSI-RS resources included in the CSI-RS resource sets over time. The UE may obtain frequency drift values for a given CSI-RS resource set by measuring a first CSI-RS resource included in the given CSI-RS resource set at a first time and by measuring the first CSI-RS resource (or a second CSI-RS resource included in the given CSI-RS resource set) at a second time. The UE may compare frequencies of the measurement of the first CSI-RS resource at the first time and the measurement of the first (or second) CSI-RS resource at the second time to obtain the frequency drift. The UE may transmit, and the network node may receive, a CSI report that includes the one or more frequency drift values.

In some aspects, the one or more frequency drift values may be associated with respective pairs of CSI-RS resource sets. For example, a frequency drift value may be associated with a pair of CSI-RS resource sets in that the frequency drift value may be a difference between a first frequency drift value of a first CSI-RS resource set (for example, included in the pair of CSI-RS resource sets) and a second CSI-RS resource set (for example, included in the pair of CSI-RS resource sets) . For example, the frequency drift values included in the CSI report may be relative frequency drift values indicating differences between frequency drift values of two CSI-RS resource sets (for example, and in turn two TRPs) . In some aspects, a pair of CSI-RS resource sets may include an anchor CSI-RS resource set (for example, that is included in each pair of CSI-RS resource sets) and a non-anchor CSI-RS resource set from the CSI-RS resource sets configured by the CSI configuration.

Particular aspects of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. In some examples, the described techniques can be used to synchronize how and when a UE is to transmit a frequency drift report (for example, a CSI report that includes one or more frequency drift values) to a network node. For example, by configuring the one or more CSI-RS resource sets for frequency drift reporting (for example, via a report quantity parameter) , the UE may identify which CSI-RS resources are to be measured to obtain the frequency drift values. Further, by configuring the one or more CSI-RS resource sets for frequency drift reporting, the network node may configure the UE to measure frequency drifts associated with different TRPs included in a multi-TRP deployment. In some aspects, by transmitting the frequency drift report, a performance and/or reliability of CJT transmissions in the multi-TRP deployment may be improved. For example, the network node may use the one or more frequency drift values to make improved adjustments (for example, to a phase or precoder) of TRPs, thereby improving the performance and/or reliability of CJT transmissions in the multi-TRP deployment.

Additionally, by including relative frequency drift values (for example, associated with a pair of CSI-RS resource sets) in the frequency drift report, the network node may be enabled to compare frequency drifts between two TRPs that may be used to communicate with the UE in the multi-TRP deployment. Additionally, the relative frequency drift values (for example, the difference between two frequency drift values) may consume less space in the frequency drift report (for example, as compared to including the two frequency drift values) , thereby reducing a size of the frequency drift report and/or reducing signaling overhead associated with transmitting the frequency drift report.

Multiple-access radio access technologies (RATs) have been adopted in various telecommunication standards to provide common protocols that enable wireless communication devices to communicate on a municipal, enterprise, national, regional, or global level. For example, 5G New Radio (NR) is part of a continuous mobile broadband evolution promulgated by the Third Generation Partnership Project (3GPP) . 5G NR supports various technologies and use cases including enhanced mobile broadband (eMBB) , ultra-reliable low-latency communication (URLLC) , massive machine-type communication (mMTC) , millimeter wave (mmWave) technology, beamforming, network slicing, edge computing, Internet of Things (IoT) connectivity and management, and network function virtualization (NFV) .

As the demand for broadband access increases and as technologies supported by wireless communication networks evolve, further technological improvements may be adopted in or implemented for 5G NR or future RATs, such as 6G, to further advance the evolution of wireless communication for a wide variety of existing and new use cases and applications. Such technological improvements may be associated with new frequency band expansion, licensed and unlicensed spectrum access, overlapping spectrum use, small cell deployments, non-terrestrial network (NTN) deployments, disaggregated network architectures and network topology expansion, device aggregation, advanced duplex communication, sidelink and other device-to-device direct communication, IoT (including passive or ambient IoT) networks, reduced capability (RedCap) UE functionality, industrial connectivity, multiple-subscriber implementations, high-precision positioning, radio frequency (RF) sensing, and/or artificial intelligence or machine learning (AI/ML) , among other examples. These technological improvements may support use cases such as wireless backhauls, wireless data centers, extended reality (XR) and metaverse applications, meta services for supporting vehicle connectivity, holographic and mixed reality communication, autonomous and collaborative robots, vehicle platooning and cooperative maneuvering, sensing networks, gesture monitoring, human-brain interfacing, digital twin applications, asset management, and universal coverage applications using non-terrestrial and/or aerial platforms, among other examples. The methods, operations, apparatuses, and techniques described herein may enable one or more of the foregoing technologies and/or support one or more of the foregoing use cases.

Figure 1 is a diagram illustrating an example of a wireless communication network 100 in accordance with the present disclosure. The wireless communication network 100 may be or may include elements of a 5G (or NR) network or a 6G network, among other examples. The wireless communication network 100 may include multiple network nodes 110, shown as a network node (NN) 110a, a network node 110b, a network node 110c, and a network node 110d. The network nodes 110 may support communications with multiple UEs 120, shown as a UE 120a, a UE 120b, a UE 120c, a UE 120d, and a UE 120e.

The network nodes 110 and the UEs 120 of the wireless communication network 100 may communicate using the electromagnetic spectrum, which may be subdivided by frequency or wavelength into various classes, bands, carriers, and/or channels. For example, devices of the wireless communication network 100 may communicate using one or more operating bands. In some aspects, multiple wireless networks 100 may be deployed in a given geographic area. Each wireless communication network 100 may support a particular RAT (which may also be referred to as an air interface) and may operate on one or more carrier frequencies in one or more frequency ranges. Examples of RATs include a 4G RAT, a 5G/NR RAT, and/or a 6G RAT, among other examples. In some examples, when multiple RATs are deployed in a given geographic area, each RAT in the geographic area may operate on different frequencies to avoid interference with one another.

Various operating bands have been defined as frequency range designations FR1 (410 MHz through 7.125 GHz) , FR2 (24.25 GHz through 52.6 GHz) , FR3 (7.125 GHz through 24.25 GHz) , FR4a or FR4-1 (52.6 GHz through 71 GHz) , FR4 (52.6 GHz through 114.25 GHz) , and FR5 (114.25 GHz through 300 GHz) . Although a portion of FR1 is greater than 6 GHz, FR1 is often referred to (interchangeably) as a “Sub-6 GHz” band in some documents and articles. Similarly, FR2 is often referred to (interchangeably) as a “millimeter wave” band in some documents and articles, despite being different than the extremely high frequency (EHF) band (30 GHz through 300 GHz) , which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band. The frequencies between FR1 and FR2 are often referred to as mid-band frequencies, which include FR3. Frequency bands falling within FR3 may inherit FR1 characteristics or FR2 characteristics, and thus may effectively extend features of FR1 or FR2 into mid-band frequencies. Thus, “sub-6 GHz, ” if used herein, may broadly refer to frequencies that are less than 6 GHz, that are within FR1, and/or that are included in mid-band frequencies. Similarly, the term “millimeter wave, ” if used herein, may broadly refer to frequencies that are included in mid-band frequencies, that are within FR2, FR4, FR4-a or FR4-1, or FR5, and/or that are within the EHF band. Higher frequency bands may extend 5G NR operation, 6G operation, and/or other RATs beyond 52.6 GHz. For example, each of FR4a, FR4-1, FR4, and FR5 falls within the EHF band. In some examples, the wireless communication network 100 may implement dynamic spectrum sharing (DSS) , in which multiple RATs (for example, 4G/LTE and 5G/NR) are implemented with dynamic bandwidth allocation (for example, based on user demand) in a single frequency band. It is contemplated that the frequencies included in these operating bands (for example, FR1, FR2, FR3, FR4, FR4-a, FR4-1, and/or FR5) may be modified, and techniques described herein may be applicable to those modified frequency ranges.

A network node 110 may include one or more devices, components, or systems that enable communication between a UE 120 and one or more devices, components, or systems of the wireless communication network 100. A network node 110 may be, may include, or may also be referred to as an NR network node, a 5G network node, a 6G network node, a Node B, an eNB, a gNB, an access point (AP) , a transmission reception point (TRP) , a mobility element, a core, a network entity, a network element, a network equipment, and/or another type of device, component, or system included in a radio access network (RAN) .

A network node 110 may be implemented as a single physical node (for example, a single physical structure) or may be implemented as two or more physical nodes (for example, two or more distinct physical structures) . For example, a network node 110 may be a device or system that implements part of a radio protocol stack, a device or system that implements a full radio protocol stack (such as a full gNB protocol stack) , or a collection of devices or systems that collectively implement the full radio protocol stack. For example, and as shown, a network node 110 may be an aggregated network node (having an aggregated architecture) , meaning that the network node 110 may implement a full radio protocol stack that is physically and logically integrated within a single node (for example, a single physical structure) in the wireless communication network 100. For example, an aggregated network node 110 may consist of a single standalone base station or a single TRP that uses a full radio protocol stack to enable or facilitate communication between a UE 120 and a core network of the wireless communication network 100.

Alternatively, and as also shown, a network node 110 may be a disaggregated network node (sometimes referred to as a disaggregated base station) , meaning that the network node 110 may implement a radio protocol stack that is physically distributed and/or logically distributed among two or more nodes in the same geographic location or in different geographic locations. For example, a disaggregated network node may have a disaggregated architecture. In some deployments, disaggregated network nodes 110 may be used in an integrated access and backhaul (IAB) network, in an open radio access network (O-RAN) (such as a network configuration in compliance with the O-RAN Alliance) , or in a virtualized radio access network (vRAN) , also known as a cloud radio access network (C-RAN) , to facilitate scaling by separating base station functionality into multiple units that can be individually deployed.

The network nodes 110 of the wireless communication network 100 may include one or more central units (CUs) , one or more distributed units (DUs) , and/or one or more radio units (RUs) . A CU may host one or more higher layer control functions, such as radio resource control (RRC) functions, packet data convergence protocol (PDCP) functions, and/or service data adaptation protocol (SDAP) functions, among other examples. A DU may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and/or one or more higher physical (PHY) layers depending, at least in part, on a functional split, such as a functional split defined by the 3GPP. In some examples, a DU also may host one or more lower PHY layer functions, such as a fast Fourier transform (FFT) , an inverse FFT (iFFT) , beamforming, physical random access channel (PRACH) extraction and filtering, and/or scheduling of resources for one or more UEs 120, among other examples. An RU may host RF processing functions or lower PHY layer functions, such as an FFT, an iFFT, beamforming, or PRACH extraction and filtering, among other examples, according to a functional split, such as a lower layer functional split. In such an architecture, each RU can be operated to handle over the air (OTA) communication with one or more UEs 120.

In some aspects, a single network node 110 may include a combination of one or more CUs, one or more DUs, and/or one or more RUs. Additionally or alternatively, a network node 110 may include one or more Near-Real Time (Near-RT) RAN Intelligent Controllers (RICs) and/or one or more Non-Real Time (Non-RT) RICs. In some examples, a CU, a DU, and/or an RU may be implemented as a virtual unit, such as a virtual central unit (VCU) , a virtual distributed unit (VDU) , or a virtual radio unit (VRU) , among other examples. A virtual unit may be implemented as a virtual network function, such as associated with a cloud deployment.

Some network nodes 110 (for example, a base station, an RU, or a TRP) may provide communication coverage for a particular geographic area. In the 3GPP, the term “cell” can refer to a coverage area of a network node 110 or to a network node 110 itself, depending on the context in which the term is used. A network node 110 may support one or multiple (for example, three) cells. In some examples, a network node 110 may provide communication coverage for a macro cell, a pico cell, a femto cell, or another type of cell. A macro cell may cover a relatively large geographic area (for example, several kilometers in radius) and may allow unrestricted access by UEs 120 with service subscriptions. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs 120 with service subscriptions. A femto cell may cover a relatively small geographic area (for example, a home) and may allow restricted access by UEs 120 having association with the femto cell (for example, UEs 120 in a closed subscriber group (CSG) ) . A network node 110 for a macro cell may be referred to as a macro network node. A network node 110 for a pico cell may be referred to as a pico network node. A network node 110 for a femto cell may be referred to as a femto network node or an in-home network node. In some examples, a cell may not necessarily be stationary. For example, the geographic area of the cell may move according to the location of an associated mobile network node 110 (for example, a train, a satellite base station, an unmanned aerial vehicle, or an NTN network node) .

The wireless communication network 100 may be a heterogeneous network that includes network nodes 110 of different types, such as macro network nodes, pico network nodes, femto network nodes, relay network nodes, aggregated network nodes, and/or disaggregated network nodes, among other examples. In the example shown in Figure 1, the network node 110a may be a macro network node for a macro cell 130a, the network node 110b may be a pico network node for a pico cell 130b, and the network node 110c may be a femto network node for a femto cell 130c. Various different types of network nodes 110 may generally transmit at different power levels, serve different coverage areas, and/or have different impacts on interference in the wireless communication network 100 than other types of network nodes 110. For example, macro network nodes may have a high transmit power level (for example, 5 to 40 watts) , whereas pico network nodes, femto network nodes, and relay network nodes may have lower transmit power levels (for example, 0.1 to 2 watts) .

In some examples, a network node 110 may be, may include, or may operate as an RU, a TRP, or a base station that communicates with one or more UEs 120 via a radio access link (which may be referred to as a “Uu” link) . The radio access link may include a downlink and an uplink. “Downlink” (or “DL” ) refers to a communication direction from a network node 110 to a UE 120, and “uplink” (or “UL” ) refers to a communication direction from a UE 120 to a network node 110. Downlink channels may include one or more control channels and one or more data channels. A downlink control channel may be used to transmit downlink control information (DCI) (for example, scheduling information, reference signals, and/or configuration information) from a network node 110 to a UE 120. A downlink data channel may be used to transmit downlink data (for example, user data associated with a UE 120) from a network node 110 to a UE 120. Downlink control channels may include one or more physical downlink control channels (PDCCHs) , and downlink data channels may include one or more physical downlink shared channels (PDSCHs) . Uplink channels may similarly include one or more control channels and one or more data channels. An uplink control channel may be used to transmit uplink control information (UCI) (for example, reference signals and/or feedback corresponding to one or more downlink transmissions) from a UE 120 to a network node 110. An uplink data channel may be used to transmit uplink data (for example, user data associated with a UE 120) from a UE 120 to a network node 110. Uplink control channels may include one or more physical uplink control channels (PUCCHs) , and uplink data channels may include one or more physical uplink shared channels (PUSCHs) . The downlink and the uplink may each include a set of resources on which the network node 110 and the UE 120 may communicate.

Downlink and uplink resources may include time domain resources (frames, subframes, slots, and/or symbols) , frequency domain resources (frequency bands, component carriers, subcarriers, resource blocks, and/or resource elements) , and/or spatial domain resources (particular transmit directions and/or beam parameters) . Frequency domain resources of some bands may be subdivided into bandwidth parts (BWPs) . A BWP may be a continuous block of frequency domain resources (for example, a continuous block of resource blocks) that are allocated for one or more UEs 120. A UE 120 may be configured with both an uplink BWP and a downlink BWP (where the uplink BWP and the downlink BWP may be the same BWP or different BWPs) . A BWP may be dynamically configured (for example, by a network node 110 transmitting a DCI configuration to the one or more UEs 120) and/or reconfigured, which means that a BWP can be adjusted in real-time (or near-real-time) based on changing network conditions in the wireless communication network 100 and/or based on the specific requirements of the one or more UEs 120. This enables more efficient use of the available frequency domain resources in the wireless communication network 100 because fewer frequency domain resources may be allocated to a BWP for a UE 120 (which may reduce the quantity of frequency domain resources that a UE 120 is required to monitor) , leaving more frequency domain resources to be spread across multiple UEs 120. Thus, BWPs may also assist in the implementation of lower-capability UEs 120 by facilitating the configuration of smaller bandwidths for communication by such UEs 120.

As described above, in some aspects, the wireless communication network 100 may be, may include, or may be included in, an IAB network. In an IAB network, at least one network node 110 is an anchor network node that communicates with a core network. An anchor network node 110 may also be referred to as an IAB donor (or “IAB-donor” ) . The anchor network node 110 may connect to the core network via a wired backhaul link. For example, an Ng interface of the anchor network node 110 may terminate at the core network. Additionally or alternatively, an anchor network node 110 may connect to one or more devices of the core network that provide a core access and mobility management function (AMF) . An IAB network also generally includes multiple non-anchor network nodes 110, which may also be referred to as relay network nodes or simply as IAB nodes (or “IAB-nodes” ) . Each non-anchor network node 110 may communicate directly with the anchor network node 110 via a wireless backhaul link to access the core network, or may communicate indirectly with the anchor network node 110 via one or more other non-anchor network nodes 110 and associated wireless backhaul links that form a backhaul path to the core network. Some anchor network node 110 or other non-anchor network node 110 may also communicate directly with one or more UEs 120 via wireless access links that carry access traffic. In some examples, network resources for wireless communication (such as time resources, frequency resources, and/or spatial resources) may be shared between access links and backhaul links.

In some examples, any network node 110 that relays communications may be referred to as a relay network node, a relay station, or simply as a relay. A relay may receive a transmission of a communication from an upstream station (for example, another network node 110 or a UE 120) and transmit the communication to a downstream station (for example, a UE 120 or another network node 110) . In such examples, the wireless communication network 100 may include or be referred to as a “multi-hop network. ” In the example shown in Figure 1, the network node 110d (for example, a relay network node) may communicate with the network node 110a (for example, a macro network node) and the UE 120d in order to facilitate communication between the network node 110a and the UE 120d. Additionally or alternatively, a UE 120 may be or may operate as a relay station that can relay transmissions to or from other UEs 120. A UE 120 that relays communications may be referred to as a UE relay or a relay UE, among other examples.

The UEs 120 may be physically dispersed throughout the wireless communication network 100, and each UE 120 may be stationary or mobile. A UE 120 may be, may include, or may be included in an access terminal, another terminal, a mobile station, or a subscriber unit. A UE 120 may be, include, or be coupled with a cellular phone (for example, a smart phone) , a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device, a biometric device, a wearable device (for example, a smart watch, smart clothing, smart glasses, a smart wristband, and/or smart jewelry, such as a smart ring or a smart bracelet) , an entertainment device (for example, a music device, a video device, and/or a satellite radio) , an XR device, a vehicular component or sensor, a smart meter or sensor, industrial manufacturing equipment, a Global Navigation Satellite System (GNSS) device (such as a Global Positioning System device or another type of positioning device) , a UE function of a network node, and/or any other suitable device or function that may communicate via a wireless medium.

A UE 120 and/or a network node 110 may include one or more chips, system-on-chips (SoCs) , chipsets, packages, or devices that individually or collectively constitute or comprise a processing system. The processing system includes processor (or “processing” ) circuitry in the form of one or multiple processors, microprocessors, processing units (such as central processing units (CPUs) , graphics processing units (GPUs) , neural processing units (NPUs) and/or digital signal processors (DSPs) ) , processing blocks, application-specific integrated circuits (ASIC) , programmable logic devices (PLDs) (such as field programmable gate arrays (FPGAs) ) , or other discrete gate or transistor logic or circuitry (all of which may be generally referred to herein individually as “processors” or collectively as “the processor” or “the processor circuitry” ) . One or more of the processors may be individually or collectively configurable or configured to perform various functions or operations described herein. A group of processors collectively configurable or configured to perform a set of functions may include a first processor configurable or configured to perform a first function of the set and a second processor configurable or configured to perform a second function of the set, or may include the group of processors all being configured or configurable to perform the set of functions.

The processing system may further include memory circuitry in the form of one or more memory devices, memory blocks, memory elements or other discrete gate or transistor logic or circuitry, each of which may include tangible storage media such as random-access memory (RAM) or read-only memory (ROM) , or combinations thereof (all of which may be generally referred to herein individually as “memories” or collectively as “the memory” or “the memory circuitry” ) . One or more of the memories may be coupled (for example, operatively coupled, communicatively coupled, electronically coupled, or electrically coupled) with one or more of the processors and may individually or collectively store processor-executable code (such as software) that, when executed by one or more of the processors, may configure one or more of the processors to perform various functions or operations described herein. Additionally or alternatively, in some examples, one or more of the processors may be preconfigured to perform various functions or operations described herein without requiring configuration by software. The processing system may further include or be coupled with one or more modems (such as a Wi-Fi (for example, IEEE compliant) modem or a cellular (for example, 3GPP 4G LTE, 5G, or 6G compliant) modem) . In some implementations, one or more processors of the processing system include or implement one or more of the modems. The processing system may further include or be coupled with multiple radios (collectively “the radio” ) , multiple RF chains, or multiple transceivers, each of which may in turn be coupled with one or more of multiple antennas. In some implementations, one or more processors of the processing system include or implement one or more of the radios, RF chains or transceivers. The UE 120 may include or may be included in a housing that houses components associated with the UE 120 including the processing system.

Some UEs 120 may be considered machine-type communication (MTC) UEs, evolved or enhanced machine-type communication (eMTC) , UEs, further enhanced eMTC (feMTC) UEs, or enhanced feMTC (efeMTC) UEs, or further evolutions thereof, all of which may be simply referred to as “MTC UEs” . An MTC UE may be, may include, or may be included in or coupled with a robot, an uncrewed aerial vehicle, a remote device, a sensor, a meter, a monitor, and/or a location tag. Some UEs 120 may be considered IoT devices and/or may be implemented as NB-IoT (narrowband IoT) devices. An IoT UE or NB-IoT device may be, may include, or may be included in or coupled with an industrial machine, an appliance, a refrigerator, a doorbell camera device, a home automation device, and/or a light fixture, among other examples. Some UEs 120 may be considered Customer Premises Equipment, which may include telecommunications devices that are installed at a customer location (such as a home or office) to enable access to a service provider's network (such as included in or in communication with the wireless communication network 100) .

Some UEs 120 may be classified according to different categories in association with different complexities and/or different capabilities. UEs 120 in a first category may facilitate massive IoT in the wireless communication network 100, and may offer low complexity and/or cost relative to UEs 120 in a second category. UEs 120 in a second category may include mission-critical IoT devices, legacy UEs, baseline UEs, high-tier UEs, advanced UEs, full-capability UEs, and/or premium UEs that are capable of URLLC, enhanced mobile broadband (eMBB) , and/or precise positioning in the wireless communication network 100, among other examples. A third category of UEs 120 may have mid-tier complexity and/or capability (for example, a capability between UEs 120 of the first category and UEs 120 of the second capability) . A UE 120 of the third category may be referred to as a reduced capacity UE ( “RedCap UE” ) , a mid-tier UE, an NR-Light UE, and/or an NR-Lite UE, among other examples. RedCap UEs may bridge a gap between the capability and complexity of NB-IoT devices and/or eMTC UEs, and mission-critical IoT devices and/or premium UEs. RedCap UEs may include, for example, wearable devices, IoT devices, industrial sensors, and/or cameras that are associated with a limited bandwidth, power capacity, and/or transmission range, among other examples. RedCap UEs may support healthcare environments, building automation, electrical distribution, process automation, transport and logistics, and/or smart city deployments, among other examples.

In some examples, two or more UEs 120 (for example, shown as UE 120a and UE 120e) may communicate directly with one another using sidelink communications (for example, without communicating by way of a network node 110 as an intermediary) . As an example, the UE 120a may directly transmit data, control information, or other signaling as a sidelink communication to the UE 120e. This is in contrast to, for example, the UE 120a first transmitting data in an UL communication to a network node 110, which then transmits the data to the UE 120e in a DL communication. In various examples, the UEs 120 may transmit and receive sidelink communications using peer-to-peer (P2P) communication protocols, device-to-device (D2D) communication protocols, vehicle-to-everything (V2X) communication protocols (which may include vehicle-to-vehicle (V2V) protocols, vehicle-to-infrastructure (V2I) protocols, and/or vehicle-to-pedestrian (V2P) protocols) , and/or mesh network communication protocols. In some deployments and configurations, a network node 110 may schedule and/or allocate resources for sidelink communications between UEs 120 in the wireless communication network 100. In some other deployments and configurations, a UE 120 (instead of a network node 110) may perform, or collaborate or negotiate with one or more other UEs to perform, scheduling operations, resource selection operations, and/or other operations for sidelink communications.

In various examples, some of the network nodes 110 and the UEs 120 of the wireless communication network 100 may be configured for full-duplex operation in addition to half-duplex operation. A network node 110 or a UE 120 operating in a half-duplex mode may perform only one of transmission or reception during particular time resources, such as during particular slots, symbols, or other time periods. Half-duplex operation may involve time-division duplexing (TDD) , in which DL transmissions of the network node 110 and UL transmissions of the UE 120 do not occur in the same time resources (that is, the transmissions do not overlap in time) . In contrast, a network node 110 or a UE 120 operating in a full-duplex mode can transmit and receive communications concurrently (for example, in the same time resources) . By operating in a full-duplex mode, network nodes 110 and/or UEs 120 may generally increase the capacity of the network and the radio access link. In some examples, full-duplex operation may involve frequency-division duplexing (FDD) , in which DL transmissions of the network node 110 are performed in a first frequency band or on a first component carrier and transmissions of the UE 120 are performed in a second frequency band or on a second component carrier different than the first frequency band or the first component carrier, respectively. In some examples, full-duplex operation may be enabled for a UE 120 but not for a network node 110. For example, a UE 120 may simultaneously transmit an UL transmission to a first network node 110 and receive a DL transmission from a second network node 110 in the same time resources. In some other examples, full-duplex operation may be enabled for a network node 110 but not for a UE 120. For example, a network node 110 may simultaneously transmit a DL transmission to a first UE 120 and receive an UL transmission from a second UE 120 in the same time resources. In some other examples, full-duplex operation may be enabled for both a network node 110 and a UE 120.

In some examples, the UEs 120 and the network nodes 110 may perform MIMO communication. “MIMO” generally refers to transmitting or receiving multiple signals (such as multiple layers or multiple data streams) simultaneously over the same time and frequency resources. MIMO techniques generally exploit multipath propagation. MIMO may be implemented using various spatial processing or spatial multiplexing operations. In some examples, MIMO may support simultaneous transmission to multiple receivers, referred to as multi-user MIMO (MU-MIMO) . Some RATs may employ advanced MIMO techniques, such as mTRP operation (including redundant transmission or reception on multiple TRPs) , reciprocity in the time domain or the frequency domain, single-frequency-network (SFN) transmission, or non-coherent joint transmission (NC-JT) .

The network node 110 may provide the UE 120 with a configuration of transmission configuration indicator (TCI) states that indicate or correspond to beams that may be used by the UE 120, such as for receiving one or more communications via a physical channel. For example, the network node 110 may indicate (for example, using DCI) an activated TCI state to the UE 120, which the UE 120 may use to generate a beam for receiving one or more communications via the physical channel. A beam indication may be, or may include, a TCI state information element, a beam identifier (ID) , spatial relation information, a TCI state ID, a closed loop index, a panel ID, a TRP ID, and/or a sounding reference signal (SRS) set ID, among other examples. A TCI state information element (sometimes referred to as a TCI state herein) may indicate particular information associated with a beam. For example, the TCI state information element may indicate a TCI state identification (for example, a tci-StateID) , a quasi-co-location (QCL) type (for example, a qcl-Type1, qcl-Type2, qcl-TypeA, qcl-TypeB, qcl-TypeC, or a qcl-TypeD, among other examples) , a cell identification (for example, a ServCellIndex) , a bandwidth part identification (bwp-Id) , or a reference signal identification, such as a CSI-RS identification (for example, an NZP-CSI-RS-ResourceId or an SSB-Index, among other examples) . Spatial relation information may similarly indicate information associated with an uplink beam. The beam indication may be a joint or separate DL/UL beam indication in a unified TCI framework. In a unified TCI framework, a network node 110 may support common TCI state ID update and activation, which may provide common QCL and/or common UL transmission spatial filters across a set of configured component carriers. This type of beam indication may apply to intra-band CA, as well as to joint DL/UL and separate DL/UL beam indications. The common TCI state ID may imply that one reference signal determined according to the TCI state (s) indicated by a common TCI state ID is used to provide QCL Type-D indication and to determine UL transmission spatial filters across the set of configured CCs.

In some examples, the network may support a layer 1 (L1) -based beam indication using at least UE-specific (unicast) DCI to indicate joint or separate DL/UL beam indications that may be selected from active TCI states. In some examples, DCI formats 1_1 and/or 1_2 may be used for beam indication. The network node 110 may include a support mechanism for the UE 120 to acknowledge successful decoding of a beam indication. For example, the acknowledgment/negative acknowledgment of the PDSCH scheduled by the DCI carrying the beam indication may also be used as an acknowledgement for the DCI.

In some aspects, the UE 120 may include a communication manager 140. As described in more detail elsewhere herein, the communication manager 140 may receive, from a network node, a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting; and transmit, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets. Additionally or alternatively, the communication manager 140 may perform one or more other operations described herein.

In some aspects, the network node 110 may include a communication manager 150. As described in more detail elsewhere herein, the communication manager 150 may transmit a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting; and receive, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets. Additionally or alternatively, the communication manager 150 may perform one or more other operations described herein.

Figure 2 is a diagram illustrating an example network node 110 in communication with an example UE 120 in a wireless network in accordance with the present disclosure.

As shown in Figure 2, the network node 110 may include a data source 212, a transmit processor 214, a transmit (TX) MIMO processor 216, a set of modems 232 (shown as 232a through 232t, where t ≥ 1) , a set of antennas 234 (shown as 234a through 234v, where v ≥ 1) , a MIMO detector 236, a receive processor 238, a data sink 239, a controller/processor 240, a memory 242, a communication unit 244, a scheduler 246, and/or a communication manager 150, among other examples. In some configurations, one or a combination of the antenna (s) 234, the modem (s) 232, the MIMO detector 236, the receive processor 238, the transmit processor 214, and/or the TX MIMO processor 216 may be included in a transceiver of the network node 110. The transceiver may be under control of and used by one or more processors, such as the controller/processor 240, and in some aspects in conjunction with processor-readable code stored in the memory 242, to perform aspects of the methods, processes, and/or operations described herein. In some aspects, the network node 110 may include one or more interfaces, communication components, and/or other components that facilitate communication with the UE 120 or another network node.

The terms “processor, ” “controller, ” or “controller/processor” may refer to one or more controllers and/or one or more processors. For example, reference to “a/the processor, ” “a/the controller/processor, ” or the like (in the singular) should be understood to refer to any one or more of the processors described in connection with Figure 2, such as a single processor or a combination of multiple different processors. Reference to “one or more processors” should be understood to refer to any one or more of the processors described in connection with Figure 2. For example, one or more processors of the network node 110 may include transmit processor 214, TX MIMO processor 216, MIMO detector 236, receive processor 238, and/or controller/processor 240. Similarly, one or more processors of the UE 120 may include MIMO detector 256, receive processor 258, transmit processor 264, TX MIMO processor 266, and/or controller/processor 280.

In some aspects, a single processor may perform all of the operations described as being performed by the one or more processors. In some aspects, a first set of (one or more) processors of the one or more processors may perform a first operation described as being performed by the one or more processors, and a second set of (one or more) processors of the one or more processors may perform a second operation described as being performed by the one or more processors. The first set of processors and the second set of processors may be the same set of processors or may be different sets of processors. Reference to “one or more memories” should be understood to refer to any one or more memories of a corresponding device, such as the memory described in connection with Figure 2. For example, operation described as being performed by one or more memories can be performed by the same subset of the one or more memories or different subsets of the one or more memories.

For downlink communication from the network node 110 to the UE 120, the transmit processor 214 may receive data ( “downlink data” ) intended for the UE 120 (or a set of UEs that includes the UE 120) from the data source 212 (such as a data pipeline or a data queue) . In some examples, the transmit processor 214 may select one or more MCSs for the UE 120 in accordance with one or more channel quality indicators (CQIs) received from the UE 120. The network node 110 may process the data (for example, including encoding the data) for transmission to the UE 120 on a downlink in accordance with the MCS (s) selected for the UE 120 to generate data symbols. The transmit processor 214 may process system information (for example, semi-static resource partitioning information (SRPI) ) and/or control information (for example, CQI requests, grants, and/or upper layer signaling) and provide overhead symbols and/or control symbols. The transmit processor 214 may generate reference symbols for reference signals (for example, a cell-specific reference signal (CRS) , a demodulation reference signal (DMRS) , or a channel state information (CSI) reference signal (CSI- RS) ) and/or synchronization signals (for example, a primary synchronization signal (PSS) or a secondary synchronization signals (SSS) ) .

The TX MIMO processor 216 may perform spatial processing (for example, precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide a set of output symbol streams (for example, T output symbol streams) to the set of modems 232. For example, each output symbol stream may be provided to a respective modulator component (shown as MOD) of a modem 232. Each modem 232 may use the respective modulator component to process (for example, to modulate) a respective output symbol stream (for example, for orthogonal frequency division multiplexing (OFDM) ) to obtain an output sample stream. Each modem 232 may further use the respective modulator component to process (for example, convert to analog, amplify, filter, and/or upconvert) the output sample stream to obtain a time domain downlink signal. The modems 232a through 232t may together transmit a set of downlink signals (for example, T downlink signals) via the corresponding set of antennas 234.

A downlink signal may include a DCI communication, a MAC control element (MAC-CE) communication, an RRC communication, a downlink reference signal, or another type of downlink communication. Downlink signals may be transmitted on a PDCCH, a PDSCH, and/or on another downlink channel. A downlink signal may carry one or more transport blocks (TBs) of data. A TB may be a unit of data that is transmitted over an air interface in the wireless communication network 100. A data stream (for example, from the data source 212) may be encoded into multiple TBs for transmission over the air interface. The quantity of TBs used to carry the data associated with a particular data stream may be associated with a TB size common to the multiple TBs. The TB size may be based on or otherwise associated with radio channel conditions of the air interface, the MCS used for encoding the data, the downlink resources allocated for transmitting the data, and/or another parameter. In general, the larger the TB size, the greater the amount of data that can be transmitted in a single transmission, which reduces signaling overhead. However, larger TB sizes may be more prone to transmission and/or reception errors than smaller TB sizes, but such errors may be mitigated by more robust error correction techniques.

For uplink communication from the UE 120 to the network node 110, uplink signals from the UE 120 may be received by an antenna 234, may be processed by a modem 232 (for example, a demodulator component, shown as DEMOD, of a modem 232) , may be detected by the MIMO detector 236 (for example, a receive (Rx) MIMO processor) if applicable, and/or may be further processed by the receive processor 238 to obtain decoded data and/or control information. The receive processor 238 may provide the decoded data to a data sink 239 (which may be a data pipeline, a data queue, and/or another type of data sink) and provide the decoded control information to a processor, such as the controller/processor 240.

The network node 110 may use the scheduler 246 to schedule one or more UEs 120 for downlink or uplink communications. In some aspects, the scheduler 246 may use DCI to dynamically schedule DL transmissions to the UE 120 and/or UL transmissions from the UE 120. In some examples, the scheduler 246 may allocate recurring time domain resources and/or frequency domain resources that the UE 120 may use to transmit and/or receive communications using an RRC configuration (for example, a semi-static configuration) , for example, to perform semi-persistent scheduling (SPS) or to configure a configured grant (CG) for the UE 120.

One or more of the transmit processor 214, the TX MIMO processor 216, the modem 232, the antenna 234, the MIMO detector 236, the receive processor 238, and/or the controller/processor 240 may be included in an RF chain of the network node 110. An RF chain may include one or more filters, mixers, oscillators, amplifiers, analog-to-digital converters (ADCs) , and/or other devices that convert between an analog signal (such as for transmission or reception via an air interface) and a digital signal (such as for processing by one or more processors of the network node 110) . In some aspects, the RF chain may be or may be included in a transceiver of the network node 110.

In some examples, the network node 110 may use the communication unit 244 to communicate with a core network and/or with other network nodes. The communication unit 244 may support wired and/or wireless communication protocols and/or connections, such as Ethernet, optical fiber, common public radio interface (CPRI) , and/or a wired or wireless backhaul, among other examples. The network node 110 may use the communication unit 244 to transmit and/or receive data associated with the UE 120 or to perform network control signaling, among other examples. The communication unit 244 may include a transceiver and/or an interface, such as a network interface.

The UE 120 may include a set of antennas 252 (shown as antennas 252a through 252r, where r ≥ 1) , a set of modems 254 (shown as modems 254a through 254u, where u ≥ 1) , a MIMO detector 256, a receive processor 258, a data sink 260, a data source 262, a transmit processor 264, a TX MIMO processor 266, a controller/processor 280, a memory 282, and/or a communication manager 140, among other examples. One or more of the components of the UE 120 may be included in a housing 284. In some aspects, one or a combination of the antenna (s) 252, the modem (s) 254, the MIMO detector 256, the receive processor 258, the transmit processor 264, or the TX MIMO processor 266 may be included in a transceiver that is included in the UE 120. The transceiver may be under control of and used by one or more processors, such as the controller/processor 280, and in some aspects in conjunction with processor-readable code stored in the memory 282, to perform aspects of the methods, processes, or operations described herein. In some aspects, the UE 120 may include another interface, another communication component, and/or another component that facilitates communication with the network node 110 and/or another UE 120.

For downlink communication from the network node 110 to the UE 120, the set of antennas 252 may receive the downlink communications or signals from the network node 110 and may provide a set of received downlink signals (for example, R received signals) to the set of modems 254. For example, each received signal may be provided to a respective demodulator component (shown as DEMOD) of a modem 254. Each modem 254 may use the respective demodulator component to condition (for example, filter, amplify, downconvert, and/or digitize) a received signal to obtain input samples. Each modem 254 may use the respective demodulator component to further demodulate or process the input samples (for example, for OFDM) to obtain received symbols. The MIMO detector 256 may obtain received symbols from the set of modems 254, may perform MIMO detection on the received symbols if applicable, and may provide detected symbols. The receive processor 258 may process (for example, decode) the detected symbols, may provide decoded data for the UE 120 to the data sink 260 (which may include a data pipeline, a data queue, and/or an application executed on the UE 120) , and may provide decoded control information and system information to the controller/processor 280.

For uplink communication from the UE 120 to the network node 110, the transmit processor 264 may receive and process data ( “uplink data” ) from a data source 262 (such as a data pipeline, a data queue, and/or an application executed on the UE 120) and control information from the controller/processor 280. The control information may include one or more parameters, feedback, one or more signal measurements, and/or other types of control information. In some aspects, the receive processor 258 and/or the controller/processor 280 may determine, for a received signal (such as received from the network node 110 or another UE) , one or more parameters relating to transmission of the uplink communication. The one or more parameters may include a reference signal received power (RSRP) parameter, a received signal strength indicator (RSSI) parameter, a reference signal received quality (RSRQ) parameter, a CQI parameter, or a transmit power control (TPC) parameter, among other examples. The control information may include an indication of the RSRP parameter, the RSSI parameter, the RSRQ parameter, the CQI parameter, the TPC parameter, and/or another parameter. The control information may facilitate parameter selection and/or scheduling for the UE 120 by the network node 110.

The transmit processor 264 may generate reference symbols for one or more reference signals, such as an uplink DMRS, an uplink sounding reference signal (SRS) , and/or another type of reference signal. The symbols from the transmit processor 264 may be precoded by the TX MIMO processor 266, if applicable, and further processed by the set of modems 254 (for example, for DFT-s-OFDM or CP-OFDM) . The TX MIMO processor 266 may perform spatial processing (for example, precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide a set of output symbol streams (for example, U output symbol streams) to the set of modems 254. For example, each output symbol stream may be provided to a respective modulator component (shown as MOD) of a modem 254. Each modem 254 may use the respective modulator component to process (for example, to modulate) a respective output symbol stream (for example, for OFDM) to obtain an output sample stream. Each modem 254 may further use the respective modulator component to process (for example, convert to analog, amplify, filter, and/or upconvert) the output sample stream to obtain an uplink signal.

The modems 254a through 254u may transmit a set of uplink signals (for example, R uplink signals or U uplink symbols) via the corresponding set of antennas 252. An uplink signal may include a UCI communication, a MAC-CE communication, an RRC communication, or another type of uplink communication. Uplink signals may be transmitted on a PUSCH, a PUCCH, and/or another type of uplink channel. An uplink signal may carry one or more TBs of data. Sidelink data and control transmissions (that is, transmissions directly between two or more UEs 120) may generally use similar techniques as were described for uplink data and control transmission, and may use sidelink-specific channels such as a physical sidelink shared channel (PSSCH) , a physical sidelink control channel (PSCCH) , and/or a physical sidelink feedback channel (PSFCH) .

One or more antennas of the set of antennas 252 or the set of antennas 234 may include, or may be included within, one or more antenna panels, one or more antenna groups, one or more sets of antenna elements, or one or more antenna arrays, among other examples. An antenna panel, an antenna group, a set of antenna elements, or an antenna array may include one or more antenna elements (within a single housing or multiple housings) , a set of coplanar antenna elements, a set of non-coplanar antenna elements, or one or more antenna elements coupled with one or more transmission or reception components, such as one or more components of Figure 2. As used herein, “antenna” can refer to one or more antennas, one or more antenna panels, one or more antenna groups, one or more sets of antenna elements, or one or more antenna arrays. “Antenna panel” can refer to a group of antennas (such as antenna elements) arranged in an array or panel, which may facilitate beamforming by manipulating parameters of the group of antennas. “Antenna module” may refer to circuitry including one or more antennas, which may also include one or more other components (such as filters, amplifiers, or processors) associated with integrating the antenna module into a wireless communication device.

In some examples, each of the antenna elements of an antenna 234 or an antenna 252 may include one or more sub-elements for radiating or receiving radio frequency signals. For example, a single antenna element may include a first sub-element cross-polarized with a second sub-element that can be used to independently transmit cross-polarized signals. The antenna elements may include patch antennas, dipole antennas, and/or other types of antennas arranged in a linear pattern, a two-dimensional pattern, or another pattern. A spacing between antenna elements may be such that signals with a desired wavelength transmitted separately by the antenna elements may interact or interfere constructively and destructively along various directions (such as to form a desired beam) . For example, given an expected range of wavelengths or frequencies, the spacing may provide a quarter wavelength, a half wavelength, or another fraction of a wavelength of spacing between neighboring antenna elements to allow for the desired constructive and destructive interference patterns of signals transmitted by the separate antenna elements within that expected range.

The amplitudes and/or phases of signals transmitted via antenna elements and/or sub-elements may be modulated and shifted relative to each other (such as by manipulating phase shift, phase offset, and/or amplitude) to generate one or more beams, which is referred to as beamforming. The term “beam” may refer to a directional transmission of a wireless signal toward a receiving device or otherwise in a desired direction. “Beam” may also generally refer to a direction associated with such a directional signal transmission, a set of directional resources associated with the signal transmission (for example, an angle of arrival, a horizontal direction, and/or a vertical direction) , and/or a set of parameters that indicate one or more aspects of a directional signal, a direction associated with the signal, and/or a set of directional resources associated with the signal. In some implementations, antenna elements may be individually selected or deselected for directional transmission of a signal (or signals) by controlling amplitudes of one or more corresponding amplifiers and/or phases of the signal (s) to form one or more beams. The shape of a beam (such as the amplitude, width, and/or presence of side lobes) and/or the direction of a beam (such as an angle of the beam relative to a surface of an antenna array) can be dynamically controlled by modifying the phase shifts, phase offsets, and/or amplitudes of the multiple signals relative to each other.

Different UEs 120 or network nodes 110 may include different quantities of antenna elements. For example, a UE 120 may include a single antenna element, two antenna elements, four antenna elements, eight antenna elements, or a different quantity of antenna elements. As another example, a network node 110 may include eight antenna elements, 24 antenna elements, 64 antenna elements, 128 antenna elements, or a different quantity of antenna elements. Generally, a larger quantity of antenna elements may provide increased control over parameters for beam generation relative to a smaller quantity of antenna elements, whereas a smaller quantity of antenna elements may be less complex to implement and may use less power than a larger quantity of antenna elements. Multiple antenna elements may support multiple-layer transmission, in which a first layer of a communication (which may include a first data stream) and a second layer of a communication (which may include a second data stream) are transmitted using the same time and frequency resources with spatial multiplexing.

Figure 3 is a diagram illustrating an example disaggregated base station architecture 300 in accordance with the present disclosure. One or more components of the example disaggregated base station architecture 300 may be, may include, or may be included in one or more network nodes (such one or more network nodes 110) . The disaggregated base station architecture 300 may include a CU 310 that can communicate directly with a core network 320 via a backhaul link, or that can communicate indirectly with the core network 320 via one or more disaggregated control units, such as a Non-RT RIC 350 associated with a Service Management and Orchestration (SMO) Framework 360 and/or a Near-RT RIC 370 (for example, via an E2 link) . The CU 310 may communicate with one or more DUs 330 via respective midhaul links, such as via F1 interfaces. Each of the DUs 330 may communicate with one or more RUs 340 via respective fronthaul links. Each of the RUs 340 may communicate with one or more UEs 120 via respective RF access links. In some deployments, a UE 120 may be simultaneously served by multiple RUs 340.

Each of the components of the disaggregated base station architecture 300, including the CUs 310, the DUs 330, the RUs 340, the Near-RT RICs 370, the Non-RT RICs 350, and the SMO Framework 360, may include one or more interfaces or may be coupled with one or more interfaces for receiving or transmitting signals, such as data or information, via a wired or wireless transmission medium.

In some aspects, the CU 310 may be logically split into one or more CU user plane (CU-UP) units and one or more CU control plane (CU-CP) units. A CU-UP unit may communicate bidirectionally with a CU-CP unit via an interface, such as the E1 interface when implemented in an O-RAN configuration. The CU 310 may be deployed to communicate with one or more DUs 330, as necessary, for network control and signaling. Each DU 330 may correspond to a logical unit that includes one or more base station functions to control the operation of one or more RUs 340. For example, a DU 330 may host various layers, such as an RLC layer, a MAC layer, or one or more PHY layers, such as one or more high PHY layers or one or more low PHY layers. Each layer (which also may be referred to as a module) may be implemented with an interface for communicating signals with other layers (and modules) hosted by the DU 330, or for communicating signals with the control functions hosted by the CU 310. Each RU 340 may implement lower layer functionality. In some aspects, real-time and non-real-time aspects of control and user plane communication with the RU (s) 340 may be controlled by the corresponding DU 330.

The SMO Framework 360 may support RAN deployment and provisioning of non-virtualized and virtualized network elements. For non-virtualized network elements, the SMO Framework 360 may support the deployment of dedicated physical resources for RAN coverage requirements, which may be managed via an operations and maintenance interface, such as an O1 interface. For virtualized network elements, the SMO Framework 360 may interact with a cloud computing platform (such as an open cloud (O-Cloud) platform 390) to perform network element life cycle management (such as to instantiate virtualized network elements) via a cloud computing platform interface, such as an O2 interface. A virtualized network element may include, but is not limited to, a CU 310, a DU 330, an RU 340, a non-RT RIC 350, and/or a Near-RT RIC 370. In some aspects, the SMO Framework 360 may communicate with a hardware aspect of a 4G RAN, a 5G NR RAN, and/or a 6G RAN, such as an open eNB (O-eNB) 380, via an O1 interface. Additionally or alternatively, the SMO Framework 360 may communicate directly with each of one or more RUs 340 via a respective O1 interface. In some deployments, this configuration can enable each DU 330 and the CU 310 to be implemented in a cloud-based RAN architecture, such as a vRAN architecture.

The Non-RT RIC 350 may include or may implement a logical function that enables non-real-time control and optimization of RAN elements and resources, AI/ML workflows including model training and updates, and/or policy-based guidance of applications and/or features in the Near-RT RIC 370. The Non-RT RIC 350 may be coupled to or may communicate with (such as via an A1 interface) the Near-RT RIC 370. The Near-RT RIC 370 may include or may implement a logical function that enables near-real-time control and optimization of RAN elements and resources via data collection and actions via an interface (such as via an E2 interface) connecting one or more CUs 310, one or more DUs 330, and/or an O-eNB with the Near-RT RIC 370.

In some aspects, to generate AI/ML models to be deployed in the Near-RT RIC 370, the Non-RT RIC 350 may receive parameters or external enrichment information from external servers. Such information may be utilized by the Near-RT RIC 370 and may be received at the SMO Framework 360 or the Non-RT RIC 350 from non-network data sources or from network functions. In some examples, the Non-RT RIC 350 or the Near-RT RIC 370 may tune RAN behavior or performance. For example, the Non-RT RIC 350 may monitor long-term trends and patterns for performance and may employ AI/ML models to perform corrective actions via the SMO Framework 360 (such as reconfiguration via an O1 interface) or via creation of RAN management policies (such as A1 interface policies) .

As used herein, the network node 110 “outputting” or “transmitting” a communication to the UE 120 may refer to a direct transmission (for example, from the network node 110 to the UE 120) or an indirect transmission via one or more other network nodes or devices. For example, if the network node 110 is a DU, an indirect transmission to the UE 120 may include the DU outputting or transmitting a communication to an RU and the RU transmitting the communication to the UE 120, or may include causing the RU to transmit the communication (for example, triggering transmission of a physical layer reference signal) . Similarly, the UE 120 “transmitting” a communication to the network node 110 may refer to a direct transmission (for example, from the UE 120 to the network node 110) or an indirect transmission via one or more other network nodes or devices. For example, if the network node 110 is a DU, an indirect transmission to the network node 110 may include the UE 120 transmitting a communication to an RU and the RU transmitting the communication to the DU. Similarly, the network node 110 “obtaining” a communication may refer to receiving a transmission carrying the communication directly (for example, from the UE 120 to the network node 110) or receiving the communication (or information derived from reception of the communication) via one or more other network nodes or devices.

The network node 110, the controller/processor 240 of the network node 110, the UE 120, the controller/processor 280 of the UE 120, the CU 310, the DU 330, the RU 340, or any other component (s) of Figures 1, 2, or 3 may implement one or more techniques or perform one or more operations associated with frequency drift reporting, as described in more detail elsewhere herein. For example, the controller/processor 240 of the network node 110, the controller/processor 280 of the UE 120, any other component (s) of Figure 2, the CU 310, the DU 330, or the RU 340 may perform or direct operations of, for example, process 1400 of Figure 14, process 1500 of Figure 15, or other processes as described herein (alone or in conjunction with one or more other processors) . The memory 242 may store data and program codes for the network node 110, the network node 110, the CU 310, the DU 330, or the RU 340. The memory 282 may store data and program codes for the UE 120. In some examples, the memory 242 or the memory 282 may include a non-transitory computer-readable medium storing a set of instructions (for example, code or program code) for wireless communication. The memory 242 may include one or more memories, such as a single memory or multiple different memories (of the same type or of different types) . The memory 282 may include one or more memories, such as a single memory or multiple different memories (of the same type or of different types) . For example, the set of instructions, when executed (for example, directly, or after compiling, converting, or interpreting) by one or more processors of the network node 110, the UE 120, the CU 310, the DU 330, or the RU 340, may cause the one or more processors to perform process 1400 of Figure 14, process 1500 of Figure 15, or other processes as described herein. In some examples, executing instructions may include running the instructions, converting the instructions, compiling the instructions, and/or interpreting the instructions, among other examples.

In some aspects, the UE 120 includes means for receiving, from a network node, a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting; and/or means for transmitting, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets. The means for the UE 120 to perform operations described herein may include, for example, one or more of communication manager 140, antenna 252, modem 254, MIMO detector 256, receive processor 258, transmit processor 264, TX MIMO processor 266, controller/processor 280, or memory 282.

In some aspects, the network node 110 includes means for transmitting a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting; and/or means for receiving, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets. The means for the network node 110 to perform operations described herein may include, for example, one or more of communication manager 150, transmit processor 214, TX MIMO processor 216, modem 232, antenna 234, MIMO detector 236, receive processor 238, controller/processor 240, memory 242, or scheduler 246.

Figure 4 is a diagram illustrating an example of a CSI report configuration 400 in accordance with the present disclosure. The CSI report configuration 400 may be configured per bandwidth part (BWP) . A resource set may have Ks resources with the same quantity of CSI-RS ports. If Ks = 1, each resource may contain 32 CSI-RS ports (for example, if a network node 110 associated with the CSI report configuration includes 32 antenna ports) . If Ks = 2, each resource may contain at most 16 CSI-RS ports. For Ks = 2 to 8, each resource may contain up to 8 CSI-RS ports. A P-port resource has ports labeled from 3000 to 3000 (P-1) .

The CSI report configuration 400 may include a CSI resource setting for a channel measurement resource (CMR) , a CSI resource setting for CMR and CSI interference measurement (CSI-IM) or non-zero power (NZP) interference measurement resource (IMR) , and a CSI resource setting for CMR and CSI-IM and NZP-IMR. A CMR may be associated with estimating channel conditions. For example, a UE may measure a CMR to estimate the channel conditions (for example, the UE may measure a CMR to perform a channel measurement, such as an RSRP measurement) . An IMR or a CSI-IM resource may be associated with estimating interference associated with a channel. For example, a UE may measure an IMR or a CSI-IM resource to estimate the interference (for example, the UE may measure an IMR to perform an interference measurement) . Each resource setting may have one active resource set, and each resource set may have one or more resources (N resources) . A UE may evaluate CSI associated with the N NZP CMR resources and select 1 (one) CMR resource out of N resources. The UE may report a CSI-RS resource indicator (CRI) and/or a CSI-RS resource set indicator (CRSI) as part of CSI feedback. The network node may determine a reported CSI that is associated with an NZP CMR resource. The CSI report configuration may also be referred to as a “CSI report setting. ”

The CSI report configuration may include a codebook configuration that includes a codebook type, such as Type I single panel, Type I multi-panel, Type II single panel, Type II port selection, or Type II enhanced port selection. A codebook type may have an antenna configuration of Ng panels with dimensions N1 and N2. The codebook type may be associated with a DFT beam restriction. The codebook type may have a rank indicator (RI) restriction, or a limit on the quantity of layers. The CSI report configuration may be of a report configuration type (for example, periodic, semi-persistent, aperiodic) .

In some examples, a CSI report configuration (for example, a CSI-ReportConfig) for a CSI report may include a report quantity (reportQuantity) information element or parameter that indicates the quantities or parameters that are to be reported in the CSI report. In some examples, the report quantity IE may indicate what parameter (s) are to be included (or reported) in the CSI report, such as by including a value of ‘cri-SINR’ , and/or ‘ssb-Index-SINR’ , among other examples. Additionally or alternatively, the report quantity IE may indicate one or more other parameters that are to be reported in the CSI report, such as an RI parameter, a channel quality indication (CQI) parameter, a precoding matrix indication (PMI) parameter, a reference signal received power (RSRP) parameter, and/or a layer indication (LI) parameter, among other examples.

A UE may use the same set of CSI-RS resources for CSI measurements for different adaptation configurations. In some aspects, the UE may derive CSI for reduced antenna port configurations from a CSI-RS resource with a higher quantity of reports. The UE may transmit supplemental CSI (S-CSI) that is associated with reduced antenna configurations. S-CSI may be derived from the resources configured for the base antenna configuration. The UE may be configured with restriction rules on CSI-RS resources and a codebook for the reduced antenna configuration.

In an example, a CSI report configuration 0 (zero) may include a resource setting and a codebook configuration. A full antenna configuration may include a 32-port CSI-RS resource and a codebook configuration where N1 = 4 and N2 = 4. A CSI measurement and report for a reduced antenna configuration may include, for example, a 4-port CSI-RS with N1 = 2 and N2 = 1, an 8-port CSI-RS with N1 = 2 and N2 = 2, an 8-port CSI-RS with N1 = 4 and N2 = 1, or a 16-port CSI-RS with N1 = 4 and N2 = 2.

There may be two signaling approaches. One option may include separate CSI report configurations, where a CSI report configuration includes a full antenna configuration and a new supplemental configuration for reduced antenna configuration. Another option may involve using the same CSI report configuration, where a CSI report configuration is extended by adding a new information element (IE) with supplemental configuration information for a reduced (or different) antenna configuration.

In some examples, a UE may be configured with multiple CSI-RS resource sets (for example, a CSI-RS resource set may include one or more CSI-RS resources, such as CMRs, IMRs, or other CSI-RS resources) . For example, in a multi-TRP scenario, a network node may configure the UE with one or more CSI-RS resource sets corresponding to respective TRPs in the multi-TRP scenario. For example, the UE may be configured with a first one or more CSI-RS resource sets associated with (or corresponding to) a first TRP, a second one or more CSI-RS resource sets associated with (or corresponding to) a second TRP, and so on. A TRP may be configured to transmit one or more CSI-RSs in accordance with a configuration for a CSI-RS resource set that is associated with the TRP. The UE may measure one or more CSI-RSs in accordance with the configuration (s) for the multiple CSI-RS resource sets. The UE may transmit a CSI report (for example, in accordance with the CSI report configuration) indicating one or more measurements associated with the multiple CSI-RS resource sets. As a result, the network node may obtain measurement information for the TRPs associated with the multi-TRP scenario. The association between CSI-RS resource sets and TRPs may not be known to the UE (for example, may be transparent to the UE) . Instead, the UE may be configured to measure and/or report measurements for the multiple CSI-RS resource sets, and the network node may associate a measurement associated with a given CSI-RS resource set to a given TRP.

Figure 5 illustrates an example logical architecture of a distributed RAN 500 in accordance with the present disclosure. A 5G access node 505 may include an access node controller 510. The access node controller 510 may be a CU of the distributed RAN 500. In some aspects, a backhaul interface to a 5G core network 515 may terminate at the access node controller 510. The 5G core network 515 may include a 5G control plane component 520 and a 5G user plane component 525 (for example, a 5G gateway) , and the backhaul interface for one or both of the 5G control plane and the 5G user plane may terminate at the access node controller 510. Additionally or alternatively, a backhaul interface to one or more neighbor access nodes 530 (for example, another 5G access node 505 and/or an LTE access node) may terminate at the access node controller 510.

The access node controller 510 may include and/or may communicate with one or more TRPs 535 (for example, via an F1 Control (F1-C) interface and/or an F1 User (F1-U) interface) . A TRP 535 may include DU and/or an RU of the distributed RAN 500. In some examples, a TRP 535 may correspond to a network node 110 described above in connection with Fig. 1. For example, different TRPs 535 may be included in different network nodes 110. Additionally or alternatively, multiple TRPs 535 may be included in a single network node 110. In some examples, a network node 110 may include a CU (for example, access node controller 510) and/or one or more DUs (for example, one or more TRPs 535) . In some examples, a TRP 535 may be referred to as a cell, a panel, an antenna array, or an array.

A TRP 535 may be connected to a single access node controller 510 or to multiple access node controllers 510. In some examples, a dynamic configuration of split logical functions may be present within the architecture of distributed RAN 500, referred to elsewhere herein as a functional split. For example, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and/or a medium access control (MAC) layer may be configured to terminate at the access node controller 510 or at a TRP 535.

In some aspects, multiple TRPs 535 may transmit communications (for example, the same communication or different communications) in the same transmission time interval (TTI) (for example, a slot, a mini-slot, a subframe, or a symbol) or different TTIs using different QCL relationships (for example, different spatial parameters, different TCI states, different precoding parameters, and/or different beamforming parameters) . In some aspects, a TCI state may be used to indicate one or more QCL relationships. A TRP 535 may be configured to individually (for example, using dynamic selection) or jointly (for example, using joint transmission with one or more other TRPs 535) serve traffic to a UE 120.

Figure 6 is a diagram illustrating an example of multi-TRP communication 600 in accordance with the present disclosure. “Multi-TRP communication” is sometimes referred to as “multi-panel communication. ” As shown in Figure 6, multiple TRPs 605 may communicate with the same UE 120. A TRP 605 may correspond to a TRP 535 described above in connection with Figure 5.

The multiple TRPs 605 (shown as TRP A and TRP B) may communicate with the same UE 120 in a coordinated manner (for example, using coordinated multipoint transmissions) to improve reliability and/or increase throughput. The TRPs 605 may coordinate such communications via an interface between the TRPs 605 (for example, a backhaul interface and/or an access node controller 510) . The interface may have a smaller delay and/or higher capacity when the TRPs 605 are co-located at the same network node 110 (for example, when the TRPs 605 are different antenna arrays or panels of the same network node 110) , and may have a larger delay and/or lower capacity (as compared to co-location) when the TRPs 605 are located at different network nodes 110. The different TRPs 605 may communicate with the UE 120 using different QCL relationships (for example, different TCI states) , different demodulation reference signal (DMRS) ports, and/or different layers (for example, of a multi-layer communication) .

In a first multi-TRP transmission mode (for example, Mode 1) , a single PDCCH may be used to schedule downlink data communications for a single PDSCH. In such examples, multiple TRPs 605 (for example, TRP A and TRP B) may transmit communications to the UE 120 on the same PDSCH. For example, a communication may be transmitted using a single codeword with different spatial layers for different TRPs 605 (for example, where one codeword maps to a first set of layers transmitted by a first TRP 605 and maps to a second set of layers transmitted by a second TRP 605) . As another example, a communication may be transmitted using multiple codewords, where different codewords are transmitted by different TRPs 605 (for example, using different sets of layers) . In either case, different TRPs 605 may use different QCL relationships (for example, different TCI states) for different DMRS ports corresponding to different layers. For example, a first TRP 605 may use a first QCL relationship or a first TCI state for a first set of DMRS ports corresponding to a first set of layers, and a second TRP 605 may use a second (different) QCL relationship or a second (different) TCI state for a second (different) set of DMRS ports corresponding to a second (different) set of layers. In some aspects, a TCI state in downlink control information (DCI) (for example, transmitted on the PDCCH, such as DCI format 1_0 or DCI format 1_1) may indicate the first QCL relationship (for example, by indicating a first TCI state) and the second QCL relationship (for example, by indicating a second TCI state) . The first and the second TCI states may be indicated using a TCI field in the DCI. In general, the TCI field can indicate a single TCI state (for single-TRP transmission) or multiple TCI states (for multi-TRP transmission as discussed here) in this multi-TRP transmission mode (for example, Mode 1) .

In a second multi-TRP transmission mode (for example, Mode 2) , multiple PDCCHs may be used to schedule downlink data communications for multiple corresponding PDSCHs (for example, one PDCCH for each PDSCH) . In such examples, a first PDCCH may schedule a first codeword to be transmitted by a first TRP 605, and a second PDCCH may schedule a second codeword to be transmitted by a second TRP 605. Furthermore, first DCI (for example, transmitted by the first TRP 605) may schedule a first PDSCH communication associated with a first set of DMRS ports with a first QCL relationship (for example, indicated by a first TCI state) for the first TRP 605, and second DCI (for example, transmitted by the second TRP 605) may schedule a second PDSCH communication associated with a second set of DMRS ports with a second QCL relationship (for example, indicated by a second TCI state) for the second TRP 605. In such examples, DCI (for example, having DCI format 1_0 or DCI format 1_1) may indicate a corresponding TCI state for a TRP 605 corresponding to the DCI. The TCI field of a DCI indicates the corresponding TCI state (for example, the TCI field of the first DCI indicates the first TCI state and the TCI field of the second DCI indicates the second TCI state) .

In some examples, a UE may receive a downlink communication that is transmitted by multiple TRPs, such as the TRP A and the TRP B shown in Figure 6. For example, the UE may receive the downlink communication from the multiple TRPs using the same set of resources. For example, the UE may receive a single downlink communication (for example, a joint downlink communication) from two TRPs, where a first one or more layers of the downlink communication are transmitted by a first TRP, and a second one or more layers of the downlink communication are transmitted by a second TRP.

In some examples, coherent joint transmission (CJT) may be achieved across multiple TRPs. CJT may refer to a communication that is transmitted by multiple transmitters (for example, multiple TRPs) where the communication is jointly beamformed across the multiple transmitters. For example, a precoding matrix (for example, a relative phase) applied by different TRPs may be coordinated to enable the UE to coherently combine the communication at the UE. A coherent joint transmission may be achieved when phase synchronization across the multiple TRPs is possible (for example, when the multiple TRPs are driven by a same clock, when antenna ports of the multiple TRPs are quasi co-located, and/or in other scenarios) , thereby enabling a joint precoder design to be used by the multiple TRPs. In such examples, the multiple TRPs may be considered as a single (for example, virtual) TRP within which a coherent precoder is configured. For example, the UE may not be aware that multiple TRPs are transmitting a CJT communication.

To optimize performance of CJTs, a network node may synchronize a phase between TRPs in a CJT multi-TRP scenario. For example, phase synchronization between multiple TRPs may improve the likelihood of signals transmitted by the multiple TRPs being aligned in phase when combined at a UE, thereby improving constructive interference and a signal-to-noise ratio (SNR) of the received signals at the UE. For example, if phase is not synchronized among the multiple TRPs, signals from different TRPs may introduce destructive interference when combined at the UE, resulting in signal degradation and/or degraded performance. As another example, a CJT multi-TRP scenario may be associated with beamforming to direct transmitted signals toward an intended receiver (for example, the UE) . Phase synchronization may enable improved beamforming, may improve a likelihood that transmitted signals from different TRPs are transmitted in an intended spatial direction, and/or may improve a likelihood that beamformed signals from different TRPs arrive at the UE with correct phase relationships. As another example, phase synchronization may enable the UE to perform accurate channel estimation and/or equalization. For example, phase synchronization among the multiple TRPs may enable the UE to accurately estimate channel characteristics and compensate for phase distortions introduced by the channel. Phase synchronization among multiple TRPs in a CJT multi-TRP scenario may enable efficient signal combining (for example, coherent signal combining at the UE) , improved beamforming, improved interference mitigation, and/or more reliable communications, among other examples.

However, in CJT multi-TRP deployments, phase synchronization among multiple TRPs may be difficult. For example, the multiple TRPs may use different clocks (for example, resulting in timing misalignment between the multiple TRPs) , and/or antenna panels of the multiple TRPs may not be co-located (for example, the antenna panels may be at different locations or mounted on different devices) , among other examples. Therefore, a network node may compensate for differences in phase among the multiple TRPs to improve phase synchronization among the multiple TRPs. However, phase variation between two (or more) TRPs may vary over time. In other words, a difference in phase between two (or more) TRPs may not be linear over time.

For example, a signal received by a UE (for example, after performing an FFT operation) may be represented by Equation 1:

where k is a frequency domain index (for example, a subcarrier index, a resource block (RB) index, a physical RB group (PRG) index, or a subband index) , l is a time domain index (for example, a symbol index, a slot index, or another time unit index) , n is a TRP index, p is a propagation path indicator for each TRP (for example, P_n may indicate a quantity of propagation paths for a TRP n) , β_n, p may be a frequency domain and time domain common coefficient (for example, that may be based on, or otherwise associated with, a path attenuation coefficient (α_n) ) , d_k, l may be data that is transmitted on frequency resource k of time resource l (for example, in subcarrier k of symbol l) , kΔf may be a subcarrier spacing, and f_c may be a carrier frequency.

Equation 1 may include three phase terms. A first phase term may beThe first phase term may be linear over the frequency domain and common (for example, the same) over the time domain. For example, the first phase term may represent a propagation delay plus a timing alignment error. For example, may represent a TRP_n-to-1 propagation delay difference (for example, a propagation delay difference between a TRP_n and a TRP₁) at t=0, and τ_n (0) may represent the TRP_n-to-1 timing alignment error (for example, a timing alignment error between a TRP_n and a TRP₁) at t=0.

A second phase term may beThe second phase term may represent a Doppler shift of UE velocity plus a crystal oscillator (XO) drift. The second phase term may be linear over the time domain and common (for example, the same) over the frequency domain. For example, v_n may be a UE velocity with respect to a propagation path p_n of a TRP_n (for example, v_n, p=v_UEcosθ_n, p, where v_UE is the UE velocity and θ_n, p is an angle between a direction of movement of the UE and the propagation path p_n of a TRP_n) , and e_n is an XO drift of a TRP_n (for example, for a drift requirement e=0.05ppm=5×10^-8, where a worst case of drift difference between two TRPs may be 0.1ppm=10^-7) .

A third phase term may beThe third phase term may be time domain and frequency domain coupled (for example, may vary over both the time domain and the frequency domain) . The third phase term may represent a ratio between a delay and a timing alignment error over time (for example, due to UE velocity and/or clock drift) or as a Doppler scaling over frequency. The third phase term may have a relatively small value as compared to the first phase term and the second phase term. For example, the third phase term may be scaled by the subcarrier spacing, whereas the second phase term may be scaled by the carrier frequency. The carrier frequency may have a larger value than the subcarrier frequency, resulting in the second phase term having a larger value (for example, a larger impact on a total phase shift) as compared to the third phase term.

Therefore, to maintain phase coherence (for example, phase synchronization) , a precoder used by multiple TRPs may be varied over time (for example, may be time-variated) . For example, for a given PMI measured at time t₀ and a CJT downlink transmission to be transmitted at time t₁, a precoder used by a TRP_n for the CJT downlink transmission may be compensated for based on, or otherwise associated with, (the second phase term) , and/or based on (the third phase term) for a frequency resource k. However, a phase variation over time (for example, may not be linear. For example, v_n, p may be associated with multiple propagation paths of the TRP_n, where each propagation path has an independent propagation attenuation coefficient. Additionally, the UE velocity (for example, v_n, p) and/or clock drift (for example, e_n) may not be stable or consistent over a given time duration. For example, for a TRP_n, a value ofmay be different than a value ofeven if (t₀-t₁) is the same as (t₁-t₂) . In other words, a phase variation for a given TRP may vary over time. This may be referred to herein as frequency drift (for example, a time-variated phase variation may be referred to as frequency drift) .

Therefore, to ensure phase synchronization (for example, phase coherence) in a CJT multi-TRP scenario, a network node may obtain measurements or estimates of frequency drift over time. In other words, a single measurement of frequency drift may be insufficient to ensure phase synchronization because an amount by which phase varies for a given TRP (for example, as received at the UE) may not be linear over time. In some examples, such as in TDD deployments, the network node may estimate the frequency drift by measuring an uplink channel of respective TRPs and by using channel reciprocity (for example, because an uplink channel and a downlink channel may use the same frequency resources (for example, the same subband) in TDD deployments) . However, in other examples, the network node may be unable to estimate the frequency drift at the UE, such as in FDD deployments (for example, because an uplink channel and a downlink channel may use different frequency resources (for example, different subbands) in FDD deployments) .

A UE may be capable of measuring and/or estimating frequency drift of a given TRP by measuring a signal (for example, a reference signal) that is transmitted by the given TRP. However, there are currently no mechanisms defined for measuring and/or reporting frequency drift from a UE to a network node. For example, because the UE may be unaware of the existence or deployment of TRPs included in a CJT multi-TRP deployment, the UE may be unable to identify which resources or reference signals should be measured to estimate a frequency drift for a given TRP. Therefore, the UE may misidentify a resource or reference signal to measure for estimating frequency drift of a given TRP, thereby consuming network resources, processing resources, and/or memory resources, among other examples, associated with measuring and/or estimating the frequency drift for the given TRP using the misidentified resource or reference signal. Further, the UE and the network node may not be synchronized as to a reporting mechanism for reporting frequency drifts measured or estimated by the UE. As a result, the UE may transmit an indication of a frequency drift and the network node may misidentify which TRP is associated with the frequency drift. As a result, the network node may incorrectly compensate a frequency drift for a TRP, thereby degrading performance and/or reliability of a CJT in the multi-TRP scenario.

Figure 7 is a diagram of an example 700 associated with frequency drift reporting, in accordance with the present disclosure. As shown in Figure 7, a network node 110 (for example, a base station, a CU, a DU, and/or an RU) may communicate with a UE 120. In some aspects, the network node and the UE may be part of a wireless network (for example, the wireless communication network 100) . The UE 120 and the network node 110 may have established a wireless connection prior to operations shown in Figure 7. The UE 120 may receive one or more communications as part of a multi-TRP deployment. For example, the wireless communication network 100 may include a multi-TRP deployment in which multiple TRPs (shown as TRPs 705 in Figure 7) communicate with the UE 120. In some aspects, the TRPs 705 may transmit CJTs to the UE 120, as described in more detail elsewhere herein.

In some aspects, the TRPs 705 may be co-located with the network node 110 (for example, located at the same location, the same device, or the same station) . In other aspects, the TRPs 705 may not be co-located with the network node 110. In some aspects, the TRPs 705 may be co-located with each other. In other aspects, the TRPs 705 may not be co-located with each other. As an example, the network node 110 may be a DU and the TRPs 705 may be RUs associated with the DU (for example, that are managed, configured, or otherwise controlled by the DU) . As another example, the TRPs 705 may be RUs and/or DUs and the network node 110 may be a CU (for example, a CU that manages, configures, or otherwise controls operations of the TRPs 705) .

In some aspects, in a first operation 710, the UE 120 may transmit, and the network node 110 may receive, a capability report. The UE 120 may transmit the capability report via an uplink communication, a UE assistance information (UAI) communication, an uplink control information (UCI) communication, an uplink MAC control element (MAC-CE) communication, an RRC communication, a PUCCH, and/or a PUSCH, among other examples. The capability report may indicate one or more parameters associated with respective capabilities of the UE 120. The one or more parameters may be indicated via respective information elements (IEs) included in the capability report.

The capability report may indicate whether the UE 120 supports a feature and/or one or more parameters related to the feature. For example, the capability report may indicate a capability and/or parameter for frequency drift reporting. As another example, the capability report may indicate a capability and/or parameter for being configured to measure and/or report frequency drift values. One or more operations described herein may be based on capability information of the capabilities report. For example, the UE may perform a communication in accordance with the capability information, or may receive configuration information that is in accordance with the capability information.

In some aspects, the capability report may indicate UE support for being configured with a CSI report configuration with a report quantity indicating that one or more frequency drift values are to be reported in a CSI report. In some aspects, the capability report may indicate UE support for being configured with a CSI report configuration that is associated with frequency drift reporting. As another example, the capability report may indicate UE support for being configured with CSI-RS resource set pairs (for example, pairs of CSI-RS resource sets) for frequency drift reporting, as described in more detail elsewhere herein. In some aspects, the capability report may indicate UE support for transmitting an indication of CSI-RS resource set pairs used for obtaining frequency drift values.

In a second operation 715, the network node 110 may transmit, and the UE 120 may receive, configuration information. In some aspects, the UE 120 may receive the configuration information via one or more of system information signaling (for example, a master information block (MIB) and/or one or more system information blocks (SIBs) ) , RRC signaling, MAC signaling (for example, one or more MAC-CEs) , and/or DCI signaling, among other examples.

In some aspects, the configuration information may indicate one or more candidate configurations and/or communication parameters. In some aspects, the one or more candidate configurations and/or communication parameters may be selected, activated, and/or deactivated by a subsequent indication. For example, the subsequent indication may select a candidate configuration and/or communication parameter from the one or more candidate configurations and/or communication parameters. In some aspects, the subsequent indication (for example, an indication described herein) may include a dynamic indication, such as one or more MAC-CEs and/or one or more DCI messages, among other examples.

In some aspects, the configuration information may indicate that the UE 120 is to measure and/or transmit a report indicating one or more frequency drift values. For example, the configuration information may include a CSI configuration. For example, the configuration information may include a CSI report configuration or a CSI report setting, among other examples. In some aspects, the configuration information may indicate one or more CSI-RS resource configurations. The one or more CSI-RS resource configurations may be NZP CSI-RS resource configurations. In some aspects, the one or more CSI-RS resource configurations may be, or may be included in, one or more CMR configurations. Additionally or alternatively, the one or more CSI-RS resource configurations may be, or may be included in, one or more IMR configurations. The configuration information may indicate a CSI report configuration or a CSI reporting setting. The CSI report configuration or the CSI reporting setting may indicate the multiple CSI-RS resource configurations. In some aspects, the one or more CSI-RS resource configurations may be included in one or more CSI-RS resource sets.

For example, the CSI configuration may configure multiple CSI-RS resource sets. A given CSI-RS resource set may include one or more CSI-RS resources that are configured via the configuration information. A CSI-RS resource set may be associated with an identifier or index value, such as a CSI-RS resource set indicator (CRSI) . A CSI-RS resource may be associated with an identifier or index value, such as a CSI-RS resource indicator (CRI) . The configuration information may configure a CSI-RS resource set by indicating one or more CRIs of CSI-RS resources that are included in the CSI-RS resource set.

The network node 110 may determine the CSI configuration based on, or otherwise associated with, the multi-TRP deployment. For example, the network node 110 may determine an association between CSI-RS resources (or CSI-RS resource sets) and TRPs 705. For example, the network node 110 may cause TRPs 705 to be associated with (for example, to transmit CSI-RSs using resources associated with) respective CSI-RS resource sets. For example, a first TRP 705 may be associated with (for example, may transmit CSI-RS using CSI-RS resources included in) a first CSI-RS resource set, a second TRP 705 may be associated with (for example, may transmit CSI- RS using CSI-RS resources included in) a second CSI-RS resource set, and so on. The configuration information may configure the multiple CSI-RS resource sets for the UE 120. However, the configuration information may not indicate which TRPs 705 are associated with which CSI-RS resource sets. The association between TRPs 705 and configured CSI-RS resource sets may be maintained or stored by the network node 110.

In some aspects, the CSI configuration (for example, a CSI report configuration (CSI-ReportConfig) ) may include a report quantity IE or parameter (for example, a reportQuantity IE) . The report quantity may indicate what kind of “quantity” should be measured and reported by the UE 120. For example, the report quantity may indicate one or more parameters to be included in a CSI report. In some aspects, the CSI configuration may include a report quantity IE that indicates a frequency drift parameter. For example, the CSI configuration (for example, a CSI report configuration (CSI-ReportConfig) ) may include a report quantity IE set to frequency drift (for example, frequency-drift) . This may indicate that the UE 120 is to measure and/or indicate frequency drift values using CSI-RS resource sets that are indicated by the CSI configuration (for example, by the CSI report configuration) .

In some aspects, the CSI configuration (for example, a CSI report configuration (CSI-ReportConfig) ) may include a report quantity IE that indicates that the CSI configuration is associated with frequency drift reporting and one or more other purposes. For example, the configured report quantity may indicate that the CSI configuration is associated with frequency drift reporting, timing offset reporting, and/or phase offset reporting. For example, the UE 120 may be configured with a report quantity IE (for example, a report quantity setting) that indicates a combination of frequency drift reporting, timing offset reporting, and/or phase offset reporting. For example, the combinations may include (timing-offset, phase-offset, and frequency drift) , (timing-offset, and frequency drift) , (phase-offset, and frequency drift) , and/or (timing-offset, phase-offset) . The configuration of a report quantity that indicates a combination of frequency drift reporting, timing offset reporting, and/or phase offset reporting may configure the UE 120 to measure (or estimate) and report the combination of values in a single CSI report. For example, frequency drift values, timing offset values, and phase offset values may be used by the network node 110 to improve coherence and/or phase synchronization for the TRPs 705 for CJTs to the UE 120. Therefore, by configuring the UE 120 to transmit the combination of values in a single CSI report, the UE 120 and/or the network node 110 may conserve network resources, processing resources, and/or power resources, among other examples, that would have been otherwise been associated with communicating separate CSI reports to indicate frequency drift values, timing offset values, and phase offset values.

In some aspects, the configuration information (for example, the CSI configuration) may indicate whether reported frequency drift values are to be absolute values or differential values. An absolute value may be an actual frequency drift value measured or estimated by the UE 120 for a given CSI-RS resource or CSI-RS resource set. A differential value may be a difference between two absolute values. Because differential values may be smaller values, the differential values may use less space (for example, fewer bits) in the CSI report. For example, the configuration information may indicate that each frequency drift value included in the CSI report is to be an absolute value. In other aspects, the configuration information may indicate that a single absolute value is to be reported and the remaining frequency drift values in the CSI report are to be differential values that are with respect to the single absolute value.

In some aspects, the configuration information may indicate a mapping order of frequency drift values reported by the UE 120 in a CSI report. For example, the mapping order may be an order of the frequency drift values in a CSI report. In some aspects, the mapping order may be defined, or otherwise fixed, by a wireless communication standard, such as the 3GPP (for example, and not configured by the network node 110) . Synchronizing or configuring the mapping order may improve a likelihood that the network node 110 is able to correctly associate a reported frequency drift value to a CSI-RS resource set (and in turn to a TRP 705) . Different example mapping orders are described in more detail elsewhere herein.

In some aspects, the configuration information (for example, the CSI configuration) may indicate, or configure, an anchor CSI-RS resource set. For example, the configuration information (for example, the CSI configuration) may indicate that frequency drift values are to be reported as a difference in frequency drift values for two CSI-RS resource sets. By including differences in frequency drift values in a CSI report, the network node 110 may be able to identify which TRPs 705 have similar frequency drifts at the UE 120 (for example, and may therefore have improved performance for CJTs to the UE 120 as compared to other pairs of TRPs 705) .

In some aspects, the UE 120 may determine or select the anchor CSI-RS resource set. In such examples, the configuration information may indicate criteria or rules to be used by the UE 120 to determine or select the anchor CSI-RS resource set. For example, the criteria may include a signal parameter (for example, a signal strength parameter, an RSRP parameter (for example, an L1 RSRP parameter) , a signal quality parameter, an RSRQ parameter, or another signal parameter) , a CRSI parameter, or another parameter. For example, the UE 120 may select a CSI-RS resource set having a highest measured signal parameter (among measured signal parameters for respective CSI-RS resource sets included in the multiple configured CSI-RS resource set) to be the anchor CSI-RS resource set. As another example, the UE 120 may select a CSI-RS resource set having a lowest or highest CSI-RS resource set index (among CSI-RS resource set indices for respective CSI-RS resource sets included in the multiple configured CSI-RS resource set) to be the anchor CSI-RS resource set. In other aspects, the UE 120 may determine or select the anchor CSI-RS resource set using other criteria or parameters. If the UE 120 determines or selects the anchor CSI-RS resource set, then the UE 120 may include an indication (for example, an identifier or index) of the selected anchor CSI-RS resource in the CSI report. In examples where an anchor TRP is configured or selected by the UE 120, each frequency drift reported by the UE 120 may correspond to a frequency drift difference between the anchor CSI-RS resource set and a non-anchor CSI-RS resource set.

In some aspects, the configuration information (for example, the CSI configuration) may indicate, or configure, one or more pairs of CSI-RS resource sets. A pair of CSI-RS resource sets may include a first CSI-RS resource set and a second CSI-RS resource set. For example, a pair of CSI-RS resource sets may correspond to a pair of TRPs 705. In such examples, each frequency drift reported by the UE 120 may correspond to a frequency drift difference between CSI-RS resource sets included in a given pair of CSI-RS resource sets. The pairs of CSI-RS resource sets may be associated with respective identifiers or indices, such as a CSI-RS resource set pair index (CRSPI) .

In some aspects, the configuration information (for example, the CSI configuration) may indicate a quantity of frequency drift values to be reported (for example, M₁) . In other aspects, the quantity of frequency drift values to be reported (for example, M₁) may be defined, or otherwise fixed, by a wireless communication standard. In some examples, the quantity of frequency drift values to be reported may be less than or equal to the quantity of configured CSI-RS resource sets. As another example, the CSI configuration may configure the UE 120 to measure a set of frequency drift values (M₂) . The quantity of frequency drift values may be a subset of frequency drift values from the set of frequency drift values (for example, M₁ may be less than or equal to M₂) .

In some aspects, the configuration information (for example, the CSI configuration) may indicate one or more trigger states for aperiodic CSI reporting (for example, one or more aperiodic trigger states) . A list of trigger states may include zero or more aperiodic trigger states and zero or more semi-persistent trigger states. An aperiodic trigger state may be configured via an RRC parameter such as CSI-AperiodicTrigggerStateList. For example, each trigger state may contain a list of associated CSI reporting settings or a CSI report configuration (for example, based at least in part on CSI reporting setting identifiers) that may indicate one or more resource set identifiers (IDs) for channel measurement and optionally for interference measurement. A semi-persistent trigger state may be configured via an RRC parameter such as CSI-SemiPersistentOnPusch-TrigggerStateList. For example, each trigger state in the RRC parameter may be associated with one associated CSI reporting setting that indicates one or more resource set IDs for channel measurement and optionally for interference measurement. When a downlink communication (for example, DCI) indicates an identifier (for example, a codepoint) of a trigger state, the UE 120 may activate one or more configurations associated with the indicated trigger state.

In some aspects, the configuration information may indicate a configuration for one or more reference signals to be used for frequency drift measurements (for example, in addition to, or instead of, the configured CSI-RS resource sets) . For example, the network node 110 may configure one or more other downlink reference signals to assist and/or improve frequency drift measurements. For example, the other downlink reference signals may be configured to be transmitted at different times, with different periodicities, and/or with other different transmission parameters than the configured CSI-RS resource sets. For example, the configuration of the one or more other downlink reference signals may increase a measurement density to improve the frequency drift measurements by the UE 120. The frequency drift measurements described herein may use, may be based on, or may otherwise be associated with both CSI-RS resource sets and the one or more other downlink reference signals. In some aspects, the one or more other downlink reference signals may have the same (or similar) frequency domain locations as the CSI-RS resource sets. The resources for the one or more other downlink reference signals may be configured in a CSI measurement configuration (for example, CSI-MeasConfig) and/or a CSI report configuration (for example, the CSI-ReportConfig) for frequency drift reporting.

The UE 120 may configure itself based at least in part on the configuration information. In some aspects, the UE 120 may be configured to perform one or more operations described herein based at least in part on the configuration information. For example, the UE 120 may be configured to measure one or more CSI-RSs (for example, using CSI-RS resources included in one or more CSI-RS resource sets) . The UE 120 may be configured to measure or estimate one or more frequency drift values using the measurements of the one or more CSI-RSs. The UE 120 may be configured to transmit a CSI report indicating the one or more frequency drift values, as described in more detail elsewhere herein.

In some aspects, the configuration information described in connection with the second operation 715 and/or the capability report described in connection with the first operation 710 may include information transmitted via multiple communications. Additionally or alternatively, the network node 110 may transmit the configuration information, or a communication including at least a portion of the configuration information, before and/or after the UE 120 transmits the capability report. For example, the network node 110 may transmit a first portion of the configuration information before the UE 120 transmits the capability report, the UE 120 may transmit at least a portion of the capability report, and the network node 110 may transmit a second portion of the configuration information after receiving the capability report.

In a third operation 720, the TRPs 705 may transmit, and the UE 120 may receive, one or more CSI-RSs. For example, a given TRP 705 may transmit one or more CSI-RSs using respective CSI-RS resources (for example, that are included in a CSI-RS resource set associated with the given TRP 705) . The TRPs 705 may transmit the one or more CSI-RSs in accordance with the CSI configuration. For example, the TRPs 705 may transmit the one or more CSI-RSs using time domain resources, frequency domain resources, and/or other transmission parameters indicated by the CSI configuration. In some aspects, one or more CSI-RSs may be received by the UE 120 for each CSI-RS resource set included in the multiple CSI-RS resource sets configured via the CSI configuration (for example, configured in the third operation 720) .

In a fourth operation 725, the UE 120 may measure the one or more CSI-RSs. In some aspects, the UE 120 may obtain measurement information (for example, one or more measurements) of CSI-RSs configured via respective CSI-RS resource sets. For example, the UE 120 may measure CSI-RSs associated with a given CSI-RS resource set at different points in time. For example, the fourth operation 725 may include the UE 120 performing one or more processing operations (for example, RF front end processing, demodulating, decoding, and/or other processing operations) using received CSI-RSs to obtain measurement information for the received CSI-RSs. In some aspects, the one or more CSI-RSs may be tracking reference signals (TRSs) or another type of reference signal.

In a fifth operation 730, the UE 120 may estimate one or more frequency drift values for respective CSI-RS resource sets. For example, the UE 120 may estimate the one or more frequency drift values based on, using, or otherwise associated with the one or more measurements obtained in the fourth operation 725. In some aspects, the UE 120 may estimate the one or more frequency drift values using Equation 1, described above. For example, the UE 120 may use the second phase termto estimate a frequency drift value for a given CSI-RS resource set. As an example, for a given CSI-RS resource set, the UE 120 may estimate a frequency drift value usingwhere t₀ is a time of a first measurement associated with the CSI-RS resource set and t₁ is a time of a second measurement associated with the CSI-RS resource set, as described in more detail elsewhere herein. A frequency drift value may quantify a change of frequency over time. A frequency drift value may be represented in units of frequency units over time units (for example, Hertz per second) , parts per million, degrees per second (when considering phase variations due to frequency drift) , and/or as a percentage (for example, a percentage change from an initial frequency) , among other examples.

In a sixth operation 735, the UE 120 may transmit, and the network node 110 may receive, a CSI report (for example, in accordance with the configuration information communicated as part of the second operation 715) . For example, the UE 120 may transmit, and the network node 110 may receive, a CSI report indicating one or more frequency drift values. In some aspects, the CSI report may include one or more frequency drift values. The one or more frequency drift values may be absolute (or actual) values. In other aspects, one or more of the frequency drift values may be differential values (for example, indicating a difference between two absolute frequency drift values) .

In some aspects, the one or more frequency drift values may be associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets. For example, a pair of CSI-RS resource sets may include a first CSI-RS resource set and a second CSI-RS resource set. A frequency drift value for the pair of CSI-RS resource sets may be a difference between a first frequency drift value associated with the first CSI-RS resource set and a second frequency drift value associated with the second CSI-RS resource set. A frequency drift value may be associated with a CSI-RS resource set in that the UE 120 obtains the frequency drift value via a measurement of one or more CSI-RS resources included in the CSI-RS resource set, such as described in connection with the fourth operation 725 and the fifth operation 730.

In some aspects, the pairs of CSI-RS resource sets may be defined using the anchor CSI-RS resource set, as described elsewhere herein. For example, the pairs of CSI-RS resource sets may include the anchor CSI-RS resource set and respective CSI-RS resource sets from the remaining non-anchor CSI-RS resource sets configured via the configuration information (for example, as part of the second operation 715) . In such examples, the one or more frequency drift values may indicate frequency drift differences associated with (for example, between) the anchor CSI-RS resource set and the respective (non-anchor) CSI-RS resource sets from the multiple CSI-RS resource sets.

As another example, the pairs of CSI-RS resource sets may be configured (for example, as part of the second operation 715) and/or determined by the UE 120. In such examples, the one or more frequency drift values may indicate frequency drift differences associated with (for example, between) CSI-RS resource sets included in respective pairs.

As described elsewhere herein, the CSI report may include the one or more frequency drift values ordered (for example, in a mapping order) . In some aspects, the CSI report includes the one or more frequency drift values ordered in accordance with index values of the respective CSI-RS resource sets. For example, the mapping order of the CSI fields may be based on, or otherwise associated with, the CSI-RS resource set index, such as in an ascending order or a descending order of CSI-RS resource set indices. As another example, the CSI report may include the one or more frequency drift values ordered in accordance with index values of the respective pairs of CSI-RS resource sets (for example, in an ascending order or a descending order of CSI-RS resource set pair indices) . The CSI-RS resource set pair index may be an index specific to, or configured for, a CSI-RS resource set pair, may be an index of a non-anchor CSI-RS resource set included in the pair, or may be an index of a first (or second) CSI-RS resource set included in the pair, among other examples.

As another example, the CSI report may include the one or more frequency drift values ordered in accordance with signal parameter measurements of the respective CSI-RS resource sets. The signal parameter may include a signal strength parameter, an RSRP parameter (for example, an L1 RSRP parameter) , a signal quality parameter, an RSRQ parameter, or another signal parameter. The UE 120 may obtain the signal parameter measurements as part of the fourth operation 725. In such examples, the CSI report may include the signal parameter measurements (for example, to enable the network node 110 to determine the mapping order) .

For example, a mapping order of the CSI fields may be based on, or otherwise associated with, a measured L1-RSRP with a descending order. In examples where the frequency drift values are associated with a pair of CSI-RS resource sets, there may be two signal parameter values for each pair. In such examples, a mapping order may be firstly based on a first signal parameter value in the CSI-RS resource set pair. If the first signal parameter value is the same between two pairs of CSI-RS resource sets, then the UE 120 may compare the second signal parameters for the second CSI-RS resource sets. For example, if two pairs of CSI-RS resource sets include a common CSI-RS resource set, then the UE 120 may order the frequency drift values for the two pairs of CSI-RS resource sets in accordance with signal parameter values for the CSI-RS resource sets that are not common among the two pairs of CSI-RS resource sets. For example, if a first pair includes (CSI-RS resource set 0, CSI-RS resource set 1) and a second pair includes (CSI-RS resource set 0, CSI-RS resource set 2) , then the UE 120 may order the frequency drift values for the two pairs of CSI-RS resource sets in accordance with signal parameter values for the CSI-RS resource set 1 and the CSI-RS resource set 2.

In some aspects, all measured or estimated frequency drift values (for example, estimated by the UE 120 in accordance with the configuration information) may be included in the CSI report. In other aspects, less than all of the measured or estimated frequency drift values may be included in the CSI report. For example, the one or more frequency drift values included in the CSI report may be a subset of frequency drift values from a set of frequency drift values estimated by the UE 120. For example, as described elsewhere herein, the CSI report may be configured to include a given quantity of frequency drift values (for example, M₁ frequency drift values) .

In such examples, the CSI report may include identifiers or indices of CSI-RS resource sets (or pairs of CSI-RS resource sets) that are associated with the M₁ frequency drift values that are included in the CSI report (for example, to enable the network node 110 to determine which CSI-RS resource sets (and which TRPs 705) are associated with the reported frequency drift values) . For example, an m^th frequency drift value in the CSI report may be associated with an m^th reported identifier or index of CSI-RS resource sets (or pairs of CSI-RS resource sets) .

In some aspects, the M₁ frequency drift values may be selected using a comparison of the set of frequency drift values. For example, the UE 120 may include the M₁ smallest or largest frequency drift values from the set of frequency drift values (for example, the set of frequency drift values obtained by the UE 120 as described elsewhere herein, such as in connection with the fifth operation 730) .

As another example, the M₁ frequency drift values may be selected in accordance with signal parameter measurements of the respective CSI-RS resource sets. For example, the UE 120 may include the M₁ frequency drift values that are associated with CSI-RS resource sets having a best (or highest) M₁ signal parameter measurement (for example, L1-RSRP) among the multiple CSI-RS resource sets.

As another example, the M₁ frequency drift values may be selected in accordance with signal parameter differences of the respective CSI-RS resource sets. For example, the UE 120 may select the frequency drift value (s) associated with CSI-RS resource sets that have a signal parameter difference that satisfies a threshold. The threshold may be indicated via the configuration information (for example, in the second operation 715) or may be defined, or otherwise fixed, by a wireless communication standard. A signal parameter difference for a given CSI-RS resource set may be a difference between a signal parameter value for the given CSI-RS resource set and a highest (or best) signal parameter value from the multiple CSI-RS resource sets (for example, configured for frequency drift measurement and/or reporting as part of the second operation 715) . In examples where a frequency drift value is associated with a pair of CSI-RS resources, a frequency drift value may be associated with satisfying the threshold if signal parameter differences for both CSI-RS resource sets included in the pair satisfy the threshold.

If a quantity of CSI-RS resource sets (or frequency drift values) that are associated with satisfying the threshold (K₁) is less than M₁, then the UE 120 may select one or more additional frequency drift values (for example, that are not associated with satisfying the threshold) to be included in the CSI report, such as by selecting (M₁ -K₁) largest or smallest remaining frequency drift values. If the quantity of CSI-RS resource sets (or frequency drift values) that are associated with satisfying the threshold (K₁) is greater than M₁, then the UE 120 may select the M₁ largest or smallest frequency drift values from the K₁ frequency drift values.

In some aspects, the CSI report may include multiple parts. The multiple parts may be transmitted by the UE 120 separately. As an example, the CSI report may include a first part and a second part. The first part may indicate a quantity of the one or more frequency drift values included in the CSI report (for example, included in all parts of the CSI report) . The first part may include a first one or more frequency drift values of the one or more frequency drift values indicated via the CSI report. The second part may include a second one or more frequency drift values of the one or more frequency drift values. In some aspects, the first part may include an indication (for example, an identifier or index) of an anchor CSI-RS resource set from the multiple CSI-RS resource sets (for example, if the UE 120 determines or selects the anchor CSI-RS resource set, as described elsewhere herein) . Additionally or alternatively, the first part may include one or more index values of CSI-RS resource sets associated with the first one or more frequency drift values. For example, the first part may include CSI-RS resource set indices associated with the first one or more frequency drift values. The second part may include one or more index values of CSI-RS resource sets associated with the second one or more frequency drift values. The multi-part CSI report is depicted and described in more detail in connection with Figure 11.

As described elsewhere herein, the CSI configuration may include a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for a combination of frequency drift reporting, timing offset reporting, and/or phase offset reporting. In such examples, the CSI report may include an indication of CSI-RS resource sets, from the multiple CSI-RS resource sets, that are associated with the one or more frequency drift values, the one or more timing offset values, and/or the one or more phase offset values. In some examples, the UE 120 may use a given CSI-RS resource included in a CSI-RS resource set for timing offset measurement and/or phase offset measurement (for example, where the CSI-RS resource set is used for frequency drift measurement) . For example, CSI-RS resources, for the respective CSI-RS resource sets, to be associated with the timing offset reporting or the phase offset reporting may be indicated in association with CSI-RS resource indices of the CSI-RS resources. In some example, a given CSI-RS resource (for example, to be used for timing offset measurement and/or phase offset measurement associated with a given CSI-RS resource set) may be based on, or otherwise associated with, a CSI-RS resource index of the CSI-RS resource. For example, the UE 120 may use a CSI-RS resource associated with a smallest CSI-RS resource index (among CSI-RS resource indices in the CSI-RS resource set) , a largest CSI-RS resource index (among CSI-RS resource indices in the CSI-RS resource set) , or another (for example, configured) CSI-RS resource index to identify the CSI-RS resource to be used for timing offset measurement and/or phase offset measurement for a given CSI-RS resource set.

The values included in the CSI report (for example, frequency drift values, timing offset values, and/or phase offset values) may be ordered and/or indicated in a similar manner as described elsewhere herein. Additionally, the values may be reported in a similar manner (for example, using absolute values or differential values) . In such examples, a CSI-RS resource from a CSI-RS resource set to be used to estimate or measure the timing offset and/or phase offset may be configured for the UE 120 (for example, as part of the second operation 715) . As another example, the UE 120 may select a CSI-RS resource (from a CSI-RS resource set) based on, or otherwise associated with, signal parameter values of the CSI-RS resources included in the CSI-RS resource set.

In some aspects, the CSI report may include an interlaced mapping for the combination of frequency drift reporting, timing offset reporting, and/or phase offset reporting. For example, the first timing offset and frequency drift value may be mapped to the CSI fields, followed by a second timing offset and frequency drift value, and so on until all values have been mapped to CSI fields. In other examples, the CSI report may include a sequential mapping for the combination of frequency drift reporting, timing offset reporting, and/or phase offset reporting. For example, all of the timing offsets may be mapped to a first set of contiguous CSI fields and all of the frequency drift values may be mapped to a second set of contiguous CSI fields. The interlaced mapping and sequential mapping are depicted and described in more detail in connection with Figure 12.

In some aspects, a report quantity IE or parameter may indicate that three or more report quantities (for example, frequency drift, timing offset, and phase offset) are configured for the multiple CSI-RS resource sets. For example, the indication of CSI-RS resource sets may only be included in a single CSI report from the triggered CSI reports (for example, to reduce signaling overhead) . As an example, a CSI report indicating timing offset values may include the indication of the CSI-RS resource sets, but a CSI report indicating the frequency drift values may not include the indication of the CSI-RS resource sets (and the network node 110 may assume there is an association between the order of the values in the CSI report (s) , to identify which CSI-RS resource set is associated with which reported value) . The UE 120 may receive a communication (for example, DCI) that activates or triggers a combination of the three or more report quantities. In some aspects, there may be an association between CSI-RS resources measured for the one or more timing offset values or the one or more phase offset values, and the respective pairs of CSI-RS resource sets. For example, a CSI-RS resource for an m^th timing offset measurement and/or phase offset measurement may be associated with (for example, included in) a CSI-RS resource set that is the same as the CSI-RS resource set for an m^th frequency drift measurement.

For example, if a triggered (for example, aperiodic) CSI report is associated with frequency drift, timing offset, and phase offset, then the UE 120 may expect that a CSI-RS resource for an m^th timing offset measurement may be associated with (for example, included in) a CSI-RS resource set that is the same as the CSI-RS resource set for an m^th frequency drift measurement. Additionally, the UE 120 may expect that a CSI-RS resource for an m^th phase offset measurement may be associated with (for example, included in) a CSI-RS resource set that is the same as the CSI-RS resource set for an m^th frequency drift measurement. Otherwise, the UE 120 may treat the triggered CSI report as an error case.

As another example, if a triggered (for example, aperiodic) CSI report is associated with frequency drift and timing offset, then the UE 120 may expect that a CSI-RS resource for an m^th timing offset measurement may be associated with (for example, included in) a CSI-RS resource set that is the same as the CSI-RS resource set for an m^th frequency drift measurement. Otherwise, the UE 120 may treat the triggered CSI report as an error case.

As another example, if a triggered (for example, aperiodic) CSI report is associated with frequency drift and phase offset, then the UE 120 may expect that a CSI-RS resource for an m^th phase offset measurement may be associated with (for example, included in) a CSI-RS resource set that is the same as the CSI-RS resource set for an m^th frequency drift measurement. Otherwise, the UE 120 may treat the triggered CSI report as an error case. As another example, if a triggered (for example, aperiodic) CSI report is associated with phase offset and timing offset, then the UE 120 may expect that a CSI-RS resource used for a timing offset measurement is also associated with a phase offset measurement.

In some aspects, the UE 120 may transmit, and the network node 110 may receive, the CSI report as part of a PMI update operation. Additionally or alternatively, the UE 120 may transmit, and the network node 110 may receive, the CSI report as part of a phase update operation.

In a seventh operation 740, the network node 110 may perform an action associated with the one or more frequency drift values. For example, the network node 110 may select two or more TRPs 705 to be used for CJTs to the UE 120 based on, in response to, or otherwise associated with the one or more frequency drift values. For example, the network node 110 may identify two or more TRPs 705 that are associated with similar (or the smallest) frequency drift values as measured or experienced at the UE 120. The network node 110 may configure the identified TRPs 705 to transmit one or more CJTs to the UE 120.

As another example, the network node 110 may perform an action to compensate a phase variation for one or more TRPs 705 using the one or more frequency drift values. For example, a reported frequency drift value may be a difference between two measured or estimated frequency drift values at the UE 120. The network node 110 may use the difference to compensate for a phase variation between two TRPs 705 (for example, that are associated with the reported frequency drift value) . In some aspects, the network node 110 may update a precoder used by the TRPs 705 based on, or otherwise associated with, the one or more frequency drift values. As another example, the network node 110 may update phases for respective TRPs 705 based on, using, or otherwise associated with the one or more frequency drift values.

In an eighth operation 745, the TRPs 705 may transmit, and the UE 120 may receive, a CJT downlink communication. The UE 120 may coherently combine the signals from multiple TRPs 705 to obtain the downlink communication. The downlink communication may be a PDSCH communication or another downlink communication. By the UE 120 transmitting the CSI report indicating the one or more frequency drift values (and the network node 110 performing the action) , a performance and/or reliability of the CJT downlink communication may be improved. For example, the CSI report indicating the one or more frequency drift values may improve a likelihood that the network node 110 is able to maintain phase synchronization or phase coherence among the multiple TRPs 705 for the CJT downlink communication as received by the UE 120.

Figure 8 is a diagram of an example associated with frequency drift reporting in accordance with the present disclosure. As shown in Figure 8, the CSI report described herein may include N-1 frequency drift values for CSI-RS resource set 0 through CSI-RS resource set N-1. For example, N CSI-RS resource sets may be configured to enable N-1 frequency drift measurements. In other words, the CSI report may include a frequency drift value for each configured CSI-RS resource set. The reported values may be included in (for example, mapped to, in a mapping order, as described in more detail elsewhere herein) CSI fields of the CSI report.

A first CSI report option 800 may be associated with the UE 120 including N-1 frequency drift values in the CSI report. The frequency drift values may be absolute values (for example, may be the actual values measured or estimated by the UE 120) . In a second CSI report option 805, one or more of the frequency drift values may be differential values. For example, a first frequency drift value in the CSI report may be an absolute value and the remaining frequency drift values may be relative to the absolute value (for example, the absolute frequency drift 1 shown in Figure 8) . For example, a value indicated by the differential frequency drift 2 may be the absolute frequency drift 1 minus an absolute frequency drift 2. Similarly, a value indicated by the differential frequency drift (N-1) may be the absolute frequency drift 1 minus an absolute frequency drift (N-1) .

Figure 9 is a diagram of an example associated with frequency drift reporting in accordance with the present disclosure. As shown in Figure 9, in a first CSI report option 900, the CSI report described herein may include N-1 frequency drift values for CSI-RS resource set 0 through CSI-RS resource set N-1. In other words, the CSI report may include a frequency drift value for each configured CSI-RS resource set. As described elsewhere herein, a frequency drift value 910 included in the CSI report may be a frequency drift difference between a first frequency drift value of a first CSI-RS resource set and a second frequency drift value of a second CSI-RS resource set. The first CSI-RS resource set may be an anchor CSI-RS resource set and the second CSI-RS resource set may be a non-anchor CSI-RS resource set. In other examples, the first CSI-RS resource set and the second CSI-RS resource set may be included in a pair of CSI-RS resource sets.

In a second CSI report option 905, less than the N-1 frequency drift values may be included in the CSI report. For example, as described in more detail elsewhere herein, the UE 120 may include M₁ frequency drift values in the CSI report. In such examples, the UE 120 may include indications of the CSI-RS resource sets (for example, CRSIs) or indications of the pair of CSI-RS resource sets (for example, CRSPIs) for respective frequency drift values of the M₁ frequency drift values. For example, as shown in Figure 9, the CRSIs or the CRSPIs may be included before the M₁ frequency drift values in the CSI report.

Figure 10 is a diagram of an example associated with frequency drift reporting in accordance with the present disclosure. As shown in Figure 10, the UE 120 may determine or select the anchor CSI-RS resource set, as described in more detail elsewhere herein. In such examples, the UE 120 may include an indication of (for example, an identifier of, or an index of) the selected anchor CSI-RS resource set in the CSI report.

For example, in a first CSI report option 1000, the CSI report described herein may include N-1 frequency drift values for CSI-RS resource set 0 through CSI-RS resource set N-1. In other words, the CSI report may include a frequency drift value for each configured CSI-RS resource set. In such examples, the CSI report may include the indication of (for example, an identifier of, or an index of) the selected anchor CSI-RS resource set and the N-1 frequency drift values. As described elsewhere herein, a frequency drift value 1010 included in the CSI report may be a frequency drift difference between a first frequency drift value of the anchor CSI-RS resource set and a second frequency drift value of a non-anchor CSI-RS resource set.

In a second CSI report option 1005, less than the N-1 frequency drift values may be included in the CSI report. For example, as described in more detail elsewhere herein, the UE 120 may include M₁ frequency drift values in the CSI report. In such examples, the UE 120 may include the indication of (for example, an identifier of, or an index of) the selected anchor CSI-RS resource set, indications of the CSI-RS resource sets (for example, CRSIs) or indications of the pair of CSI-RS resource sets (for example, CRSPIs) for respective frequency drift values of the M₁ frequency drift values, and the M₁ frequency drift values in the CSI report.

Figure 11 is a diagram of an example associated with a multi-part report for frequency drift reporting in accordance with the present disclosure. As shown in Figure 11, the CSI report may include a first part 1100 (shown as CSI part 1) and a second part 1105 (shown as CSI part 2) . As an example, the CSI report may include M₁ frequency drift values. In the first part 1100, a quantity of the M₁ frequency drift values may be indicated (for example, as shown by “#of reported frequency drifts” in Figure 11) . The first part 1100 may include indications of (for example, identifiers or indices of) CSI-RS resource sets associated with respective frequency drift values that are included in the first part 1100. For example, as shown in Figure 11, the first part 1100 may include a CRSI 1 corresponding to a frequency drift 1 (for example, the CRSI 1 may indicate a CSI-RS resource set associated with the frequency drift 1) and a CRSI 2 corresponding to a frequency drift 2 (for example, the CRSI 2 may indicate a CSI-RS resource set associated with the frequency drift 2) .

The second part 1105 may include indications of (for example, identifiers or indices of) CSI-RS resource sets associated with respective frequency drift values that are included in the second part 1105 and may include the frequency drift values. For example, the second part 1105 may include a CRSI 3 through a CRSI M₁ and a frequency drift 3 through a frequency drift M₁.

Figure 12 is a diagram of an example associated with a combined report for frequency drift reporting in accordance with the present disclosure. For example, the combined report (for example, the CSI report) may include frequency drift values and one or more other types of values, such as timing offset values (as shown in Figure 11 as an example) and/or phase offset values, among other examples.

In a first CSI report option 1200, the CSI report may include an interlaced mapping. For example, a timing offset 1 (for example, a first timing offset value) and a frequency drift 1 (for example, a first frequency drift value) may be mapped to the CSI fields, followed by a timing offset 2 (for example, a second timing offset value) and a frequency drift 2 (for example, a second frequency drift value) , and so on until all values have been mapped to CSI fields. The timing offset 1 and the frequency drift 1 may be associated with the same CSI-RS resource set. For example, the timing offset 1 may be measured by the UE 120 using a CSI-RS resource included in the CSI-RS resource set that is used to estimate the frequency drift 1.

In a CSI report option 1205, the CSI report may include a sequential mapping. For example, all of the timing offsets may be mapped to a first set of contiguous CSI fields and all of the frequency drift values may be mapped to a second set of contiguous CSI fields. For example, N-1 timing offset values may be included in the CSI report in contiguous CSI fields followed by N-1 frequency drift values. The N-1 timing offset values and the N-1 frequency drift values may follow a same order (for example, 1 through N-1) . As described elsewhere herein, an m^th timing offset value and an m^th frequency drift value may be associated with the same CSI-RS resource set (for example, the timing offset 2 and the frequency drift 2 may be associated with the same CSI-RS resource set) . Therefore, following the same order (for example, 1 through N-1) for the reported values may enable the network node 110 to correlate the different reported values to a given TRP 705.

Figure 13 is a diagram of an example 1300 associated with aperiodic reporting for frequency drift reporting in accordance with the present disclosure. As shown in Figure 13, a DCI 1305 (for example, that is transmitted by the network node 110 and received by the UE 120) may include an indication of a CSI trigger state. For example, the DCI 1305 may include a codepoint of the CSI trigger state 1. As shown in Figure 13, one or more (for example, a list) of CSI trigger states 1310 may be configured for the UE 120 (for example, via a CSI-AperiodicTriggerStateList IE) .

Each CSI trigger state may be associated with one or more CSI report configurations. For example, the CSI trigger state 1 may be associated with three CSI report configurations. Each CSI report configuration may be associated with a given CSI report configuration (for example, a CSI-ReportConfig) . As an example, the CSI trigger state 1 may be associated with triggering timing offset reporting, phase offset reporting, and frequency drift reporting. For example, as shown in Figure 13, the CSI trigger state 1 may be associated with a first CSI report configuration with a report quantity set to timing-offset, a second CSI report configuration with a report quantity set to phase-offset, and third CSI report configuration with a report quantity set to frequency drift.

The UE 120 may expect that each of the associated CSI report configurations are associated with the same one or more CSI-RS resource sets. As described elsewhere herein, there may be an association between CSI-RS resources measured for the one or more timing offset values or the one or more phase offset values, and the respective pairs of CSI-RS resource sets. For example, a CSI-RS resource for an m^th timing offset measurement and/or phase offset measurement may be associated with (for example, included in) a CSI-RS resource set that is the same as the CSI-RS resource set for an m^th frequency drift measurement.

For example, if a triggered (for example, aperiodic) CSI report is associated with frequency drift, timing offset, and phase offset, then the UE 120 may expect that a CSI-RS resource for an m^th timing offset measurement may be associated with (for example, included in) a CSI-RS resource set that is the same as the CSI-RS resource set for an m^th frequency drift measurement. Additionally, the UE 120 may expect that a CSI-RS resource for an m^th phase offset measurement may be associated with (for example, included in) a CSI-RS resource set that is the same as the CSI-RS resource set for an m^th frequency drift measurement. As another example, if a triggered (for example, aperiodic) CSI report is associated with frequency drift and timing offset, then the UE 120 may expect that a CSI-RS resource for an m^th timing offset measurement may be associated with (for example, included in) a CSI-RS resource set that is the same as the CSI-RS resource set for an m^th frequency drift measurement. As another example, if a triggered (for example, aperiodic) CSI report is associated with frequency drift and phase offset, then the UE 120 may expect that a CSI-RS resource for an m^th phase offset measurement may be associated with (for example, included in) a CSI-RS resource set that is the same as the CSI-RS resource set for an m^th frequency drift measurement.

Figure 14 is a flowchart illustrating an example process 1400 performed, for example, at a UE or an apparatus of a UE that supports frequency drift reporting in accordance with the present disclosure. Example process 1400 is an example where the apparatus or the UE (for example, UE 120) performs operations associated with frequency drift reporting.

As shown in Figure 14, in some aspects, process 1400 may include receiving, from a network node, a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting (block 1410) . For example, the UE (such as by using communication manager 140 or reception component 1602, depicted in Figure 16) may receive, from a network node, a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting, as described above.

As further shown in Figure 14, in some aspects, process 1400 may include transmitting, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets (block 1420) . For example, the UE (such as by using communication manager 140 or transmission component 1604, depicted in Figure 16) may transmit, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets, as described above.

Process 1400 may include additional aspects, such as any single aspect or any combination of aspects described below or in connection with one or more other processes described elsewhere herein.

In a first additional aspect, the CSI configuration includes a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for the frequency drift reporting.

In a second additional aspect, alone or in combination with the first aspect, the multiple CSI-RS resource sets include an anchor CSI-RS resource set, and the one or more frequency drift values indicate frequency drift differences associated with the anchor CSI-RS resource set and respective CSI-RS resource sets from the multiple CSI-RS resource sets.

In a third additional aspect, alone or in combination with one or more of the first and second aspects, the CSI configuration indicates the anchor CSI-RS resource set.

In a fourth additional aspect, alone or in combination with one or more of the first through third aspects, the CSI report includes the one or more frequency drift values ordered in accordance with index values of the respective CSI-RS resource sets.

In a fifth additional aspect, alone or in combination with one or more of the first through fourth aspects, the CSI report includes the one or more frequency drift values ordered in accordance with signal parameter measurements of the respective CSI-RS resource sets.

In a sixth additional aspect, alone or in combination with one or more of the first through fifth aspects, the CSI report includes the signal parameter measurements.

In a seventh additional aspect, alone or in combination with one or more of the first through sixth aspects, the one or more frequency drift values are a subset of frequency drift values from a set of frequency drift values, and the respective CSI-RS resource sets are a subset of CSI-RS resource sets of the multiple CSI-RS resource sets.

In an eighth additional aspect, alone or in combination with one or more of the first through seventh aspects, the subset of frequency drift values are selected using a comparison of the set of frequency drift values.

In a ninth additional aspect, alone or in combination with one or more of the first through eighth aspects, the subset of frequency drift values are selected in accordance with signal parameter measurements of the respective CSI-RS resource sets.

In a tenth additional aspect, alone or in combination with one or more of the first through ninth aspects, the subset of frequency drift values are selected in accordance with signal parameter differences of the respective CSI-RS resource sets.

In an eleventh additional aspect, alone or in combination with one or more of the first through tenth aspects, the anchor CSI-RS resource set is associated with a highest signal parameter measurement from signal parameter measurements of the respective CSI-RS resource sets.

In a twelfth additional aspect, alone or in combination with one or more of the first through eleventh aspects, the anchor CSI-RS resource set is selected in accordance with index values of the respective CSI-RS resource sets.

In a thirteenth additional aspect, alone or in combination with one or more of the first through twelfth aspects, the CSI report includes an indication of the anchor CSI-RS resource set.

In a fourteenth additional aspect, alone or in combination with one or more of the first through thirteenth aspects, the CSI configuration indicates the respective pairs of CSI-RS resource sets.

In a fifteenth additional aspect, alone or in combination with one or more of the first through fourteenth aspects, the CSI report includes the one or more frequency drift values ordered in accordance with index values of the respective pairs of CSI-RS resource sets.

In a sixteenth additional aspect, alone or in combination with one or more of the first through fifteenth aspects, the CSI report includes the one or more frequency drift values ordered in accordance with signal parameter measurements of the respective pairs of CSI-RS resource sets.

In a seventeenth additional aspect, alone or in combination with one or more of the first through sixteenth aspects, the one or more frequency drift values are a subset of frequency drift values from a set of frequency drift values.

In an eighteenth additional aspect, alone or in combination with one or more of the first through seventeenth aspects, the subset of frequency drift values are selected using a comparison of the set of frequency drift values.

In a nineteenth additional aspect, alone or in combination with one or more of the first through eighteenth aspects, the subset of frequency drift values are selected in accordance with signal parameter measurements of the respective pairs of CSI-RS resource sets.

In a twentieth additional aspect, alone or in combination with one or more of the first through nineteenth aspects, the subset of frequency drift values are selected in accordance with signal parameter differences of the respective pairs of CSI-RS resource sets.

In a twenty-first additional aspect, alone or in combination with one or more of the first through twentieth aspects, the CSI report includes a first part and a second part, the first part indicating a quantity of the one or more frequency drift values and a first one or more frequency drift values of the one or more frequency drift values, and the second part including a second one or more frequency drift values of the one or more frequency drift values.

In a twenty-second additional aspect, alone or in combination with one or more of the first through twenty-first aspects, the first part includes at least one of an indication of an anchor CSI-RS resource set from the multiple CSI-RS resource sets, or one or more index values of CSI-RS resource sets associated with the first one or more frequency drift values.

In a twenty-third additional aspect, alone or in combination with one or more of the first through twenty-second aspects, the second part includes one or more index values of CSI-RS resource sets associated with the second one or more frequency drift values.

In a twenty-fourth additional aspect, alone or in combination with one or more of the first through twenty-third aspects, the CSI configuration includes a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for the frequency drift reporting and at least one of timing offset reporting or phase offset reporting. In some aspects, CSI-RS resources, for the respective CSI-RS resource sets, to be associated with the timing offset reporting or the phase offset reporting are indicated in association with CSI-RS resource indices of the CSI-RS resources.

In a twenty-fifth additional aspect, alone or in combination with one or more of the first through twenty-fourth aspects, the CSI configuration indicates that the multiple CSI-RS resource sets are configured for at least one of timing offset reporting or phase offset reporting, and process 1400 includes receiving downlink control information that indicates that the CSI report is to include the one or more frequency drift values and at least one of one or more timing offset values or one or more phase offset values.

In a twenty-sixth additional aspect, alone or in combination with one or more of the first through twenty-fifth aspects, there is an association between CSI-RS resources measured for the one or more timing offset values or the one or more phase offset values, and the respective pairs of CSI-RS resource sets.

In a twenty-seventh additional aspect, alone or in combination with one or more of the first through twenty-sixth aspects, the CSI report includes an indication of CSI-RS resource sets, from the multiple CSI-RS resource sets, that are associated with the one or more frequency drift values, the one or more timing offset values, or the one or more phase offset values.

In a twenty-eighth additional aspect, alone or in combination with one or more of the first through twenty-seventh aspects, process 1400 includes receiving configuration information for one or more downlink reference signals that are associated with the frequency drift reporting, where the one or more frequency drift values are associated with the respective pairs of CSI-RS resource sets and the one or more downlink reference signals.

In a twenty-ninth additional aspect, alone or in combination with one or more of the first through twenty-eighth aspects, the multiple CSI-RS resource sets are associated with respective TRPs for a coherent joint transmission multi-TRP deployment.

Although Figure 14 shows example blocks of process 1400, in some aspects, process 1400 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Figure 14. Additionally or alternatively, two or more of the blocks of process 1400 may be performed in parallel.

Figure 15 is a flowchart illustrating an example process 1500 performed, for example, at a network node or an apparatus of a network node that supports frequency drift reporting in accordance with the present disclosure. Example process 1500 is an example where the apparatus or the network node (for example, network node 110) performs operations associated with frequency drift reporting.

As shown in Figure 15, in some aspects, process 1500 may include transmitting a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting (block 1510) . For example, the network node (such as by using communication manager 150 or transmission component 1704, depicted in Figure 17) may transmit a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting, as described above.

As further shown in Figure 15, in some aspects, process 1500 may include receiving, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets (block 1520) . For example, the network node (such as by using communication manager 150 or reception component 1702, depicted in Figure 17) may receive, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets, as described above.

Process 1500 may include additional aspects, such as any single aspect or any combination of aspects described below or in connection with one or more other processes described elsewhere herein.

In a twenty-fifth additional aspect, alone or in combination with one or more of the first through twenty-fourth aspects, the CSI configuration indicates that the multiple CSI-RS resource sets are configured for at least one of timing offset reporting or phase offset reporting, and process 1500 includes transmitting downlink control information that indicates that the CSI report is to include the one or more frequency drift values and at least one of one or more timing offset values or one or more phase offset values.

In a twenty-eighth additional aspect, alone or in combination with one or more of the first through twenty-seventh aspects, process 1500 includes transmitting configuration information for one or more downlink reference signals that are associated with the frequency drift reporting, where the one or more frequency drift values are associated with the respective pairs of CSI-RS resource sets and the one or more downlink reference signals.

Although Figure 15 shows example blocks of process 1500, in some aspects, process 1500 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Figure 15. Additionally or alternatively, two or more of the blocks of process 1500 may be performed in parallel.

Figure 16 is a diagram of an example apparatus 1600 for wireless communication that supports frequency drift reporting in accordance with the present disclosure. The apparatus 1600 may be a UE, or a UE may include the apparatus 1600. In some aspects, the apparatus 1600 includes a reception component 1602, a transmission component 1604, and a communication manager 140, which may be in communication with one another (for example, via one or more buses) . As shown, the apparatus 1600 may communicate with another apparatus 1606 (such as a UE, a network node, or another wireless communication device) using the reception component 1602 and the transmission component 1604.

In some aspects, the apparatus 1600 may be configured to and/or operable to perform one or more operations described herein in connection with Figures 7-13. Additionally or alternatively, the apparatus 1600 may be configured to and/or operable to perform one or more processes described herein, such as process 1400 of Figure 14. In some aspects, the apparatus 1600 may include one or more components of the UE described above in connection with Figure 2.

The reception component 1602 may receive communications, such as reference signals, control information, and/or data communications, from the apparatus 1606. The reception component 1602 may provide received communications to one or more other components of the apparatus 1600, such as the communication manager 140. In some aspects, the reception component 1602 may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples) , and may provide the processed signals to the one or more other components. In some aspects, the reception component 1602 may include one or more antennas, one or more modems, one or more demodulators, one or more MIMO detectors, one or more receive processors, one or more controllers/processors, and/or one or more memories of the UE described above in connection with Figure 2.

The transmission component 1604 may transmit communications, such as reference signals, control information, and/or data communications, to the apparatus 1606. In some aspects, the communication manager 140 may generate communications and may transmit the generated communications to the transmission component 1604 for transmission to the apparatus 1606. In some aspects, the transmission component 1604 may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples) , and may transmit the processed signals to the apparatus 1606. In some aspects, the transmission component 1604 may include one or more antennas, one or more modems, one or more modulators, one or more transmit MIMO processors, one or more transmit processors, one or more controllers/processors, and/or one or more memories of the UE described above in connection with Figure 2. In some aspects, the transmission component 1604 may be co-located with the reception component 1602 in one or more transceivers.

The communication manager 140 may receive or may cause the reception component 1602 to receive, from a network node, a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The communication manager 140 may transmit or may cause the transmission component 1604 to transmit, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets. In some aspects, the communication manager 140 may perform one or more operations described elsewhere herein as being performed by one or more components of the communication manager 140.

The communication manager 140 may include one or more controllers/processors, one or more memories, of the UE described above in connection with Figure 2. In some aspects, the communication manager 140 includes a set of components, such as a frequency drift estimation component 1608, among other examples. Alternatively, the set of components may be separate and distinct from the communication manager 140. In some aspects, one or more components of the set of components may include or may be implemented within one or more controllers/processors, one or more memories, of the UE described above in connection with Figure 2. Additionally or alternatively, one or more components of the set of components may be implemented at least in part as software stored in one or more memories. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by one or more controllers or one or more processors to perform the functions or operations of the component.

The reception component 1602 may receive, from a network node, a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The transmission component 1604 may transmit, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

The frequency drift estimation component 1608 may estimate the one or more frequency drift values using measurements of one or more CSI-RSs associated with the respective pairs of CSI-RS resource sets.

The reception component 1602 may receive configuration information for one or more downlink reference signals that are associated with the frequency drift reporting, wherein the one or more frequency drift values are associated with the respective pairs of CSI-RS resource sets and the one or more downlink reference signals.

The quantity and arrangement of components shown in Figure 16 are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in Figure 16. Furthermore, two or more components shown in Figure 16 may be implemented within a single component, or a single component shown in Figure 16 may be implemented as multiple, distributed components. Additionally or alternatively, a set of (one or more) components shown in Figure 16 may perform one or more functions described as being performed by another set of components shown in Figure 16.

Figure 17 is a diagram of an example apparatus 1700 for wireless communication that supports frequency drift reporting in accordance with the present disclosure. The apparatus 1700 may be a network node, or a network node may include the apparatus 1700. In some aspects, the apparatus 1700 includes a reception component 1702, a transmission component 1704, and a communication manager 150, which may be in communication with one another (for example, via one or more buses) . As shown, the apparatus 1700 may communicate with another apparatus 1706 (such as a UE, a network node, or another wireless communication device) using the reception component 1702 and the transmission component 1704.

In some aspects, the apparatus 1700 may be configured to and/or operable to perform one or more operations described herein in connection with Figures 7-13. Additionally or alternatively, the apparatus 1700 may be configured to and/or operable to perform one or more processes described herein, such as process 1500 of Figure 15. In some aspects, the apparatus 1700 may include one or more components of the network node described above in connection with Figure 2.

The reception component 1702 may receive communications, such as reference signals, control information, and/or data communications, from the apparatus 1706. The reception component 1702 may provide received communications to one or more other components of the apparatus 1700, such as the communication manager 150. In some aspects, the reception component 1702 may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples) , and may provide the processed signals to the one or more other components. In some aspects, the reception component 1702 may include one or more antennas, one or more modems, one or more demodulators, one or more MIMO detectors, one or more receive processors, one or more controllers/processors, and/or one or more memories of the network node described above in connection with Figure 2.

The transmission component 1704 may transmit communications, such as reference signals, control information, and/or data communications, to the apparatus 1706. In some aspects, the communication manager 150 may generate communications and may transmit the generated communications to the transmission component 1704 for transmission to the apparatus 1706. In some aspects, the transmission component 1704 may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples) , and may transmit the processed signals to the apparatus 1706. In some aspects, the transmission component 1704 may include one or more antennas, one or more modems, one or more modulators, one or more transmit MIMO processors, one or more transmit processors, one or more controllers/processors, and/or one or more memories of the network node described above in connection with Figure 2. In some aspects, the transmission component 1704 may be co-located with the reception component 1702 in one or more transceivers.

The communication manager 150 may transmit or may cause the transmission component 1704 to transmit a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The communication manager 150 may receive or may cause the reception component 1702 to receive, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets. In some aspects, the communication manager 150 may perform one or more operations described elsewhere herein as being performed by one or more components of the communication manager 150.

The communication manager 150 may include one or more controllers/processors, one or more memories, one or more schedulers, and/or one or more communication units of the network node described above in connection with Figure 2. In some aspects, the communication manager 150 includes a set of components, such as a phase management component 1708, among other examples. Alternatively, the set of components may be separate and distinct from the communication manager 150. In some aspects, one or more components of the set of components may include or may be implemented within one or more controllers/processors, one or more memories, one or more schedulers, and/or one or more communication units of the network node described above in connection with Figure 2. Additionally or alternatively, one or more components of the set of components may be implemented at least in part as software stored in one or more memories. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by one or more controllers or one or more processors to perform the functions or operations of the component.

The transmission component 1704 may transmit a CSI configuration indicating multiple CSI-RS resource sets that are configured for frequency drift reporting. The reception component 1702 may receive, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

The transmission component 1704 may transmit configuration information for one or more downlink reference signals that are associated with the frequency drift reporting, wherein the one or more frequency drift values are associated with the respective pairs of CSI-RS resource sets and the one or more downlink reference signals.

The phase management component 1708 may perform one or more actions using the one or more frequency drift values to modify a phase or precoder of one or more TRPs in a CJT multi-TRP deployment.

The quantity and arrangement of components shown in Figure 17 are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in Figure 17. Furthermore, two or more components shown in Figure 17 may be implemented within a single component, or a single component shown in Figure 17 may be implemented as multiple, distributed components. Additionally or alternatively, a set of (one or more) components shown in Figure 17 may perform one or more functions described as being performed by another set of components shown in Figure 17.

The following provides an overview of some Aspects of the present disclosure:

Aspect 1: A method of wireless communication by a user equipment (UE) , comprising: receiving, from a network node, a channel state information (CSI) configuration indicating multiple CSI reference signal (CSI-RS) resource sets that are configured for frequency drift reporting; and transmitting, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

Aspect 2: The method of Aspect 1, wherein the CSI configuration includes a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for the frequency drift reporting.

Aspect 3: The method of any of Aspects 1-2, wherein the multiple CSI-RS resource sets include an anchor CSI-RS resource set, and the one or more frequency drift values indicate frequency drift differences associated with the anchor CSI-RS resource set and respective CSI-RS resource sets from the multiple CSI-RS resource sets.

Aspect 4: The method of Aspect 3, wherein the CSI configuration indicates the anchor CSI-RS resource set.

Aspect 5: The method of any of Aspects 3-4, wherein the CSI report includes the one or more frequency drift values ordered in accordance with index values of the respective CSI-RS resource sets.

Aspect 6: The method of any of Aspects 3-5, wherein the CSI report includes the one or more frequency drift values ordered in accordance with signal parameter measurements of the respective CSI-RS resource sets.

Aspect 7: The method of Aspect 6, wherein the CSI report includes the signal parameter measurements.

Aspect 8: The method of any of Aspects 3-6, wherein the one or more frequency drift values are a subset of frequency drift values from a set of frequency drift values, and the respective CSI-RS resource sets are a subset of CSI-RS resource sets of the multiple CSI-RS resource sets.

Aspect 9: The method of Aspect 8, wherein the subset of frequency drift values are selected using a comparison of the set of frequency drift values.

Aspect 10: The method of any of Aspects 8-9, wherein the subset of frequency drift values are selected in accordance with signal parameter measurements of the respective CSI-RS resource sets.

Aspect 11: The method of any of Aspects 8-10, wherein the subset of frequency drift values are selected in accordance with signal parameter differences of the respective CSI-RS resource sets.

Aspect 12: The method of any of Aspects 3-11, wherein the anchor CSI-RS resource set is associated with a highest signal parameter measurement from signal parameter measurements of the respective CSI-RS resource sets.

Aspect 13: The method of any of Aspects 3-12, wherein the anchor CSI-RS resource set is selected in accordance with index values of the respective CSI-RS resource sets.

Aspect 14: The method of any of Aspects 3-13, wherein the CSI report includes an indication of the anchor CSI-RS resource set.

Aspect 15: The method of any of Aspects 1-14, wherein the CSI configuration indicates the respective pairs of CSI-RS resource sets.

Aspect 16: The method of any of Aspects 1-15, wherein the CSI report includes the one or more frequency drift values ordered in accordance with index values of the respective pairs of CSI-RS resource sets.

Aspect 17: The method of any of Aspects 1-16, wherein the CSI report includes the one or more frequency drift values ordered in accordance with signal parameter measurements of the respective pairs of CSI-RS resource sets.

Aspect 18: The method of any of Aspects 1-17, wherein the one or more frequency drift values are a subset of frequency drift values from a set of frequency drift values.

Aspect 19: The method of Aspect 18, wherein the subset of frequency drift values are selected using a comparison of the set of frequency drift values.

Aspect 20: The method of any of Aspects 18-19, wherein the subset of frequency drift values are selected in accordance with signal parameter measurements of the respective pairs of CSI-RS resource sets.

Aspect 21: The method of any of Aspects 18-20, wherein the subset of frequency drift values are selected in accordance with signal parameter differences of the respective pairs of CSI-RS resource sets.

Aspect 22: The method of any of Aspects 1-21, wherein the CSI report includes a first part and a second part, the first part indicating a quantity of the one or more frequency drift values and a first one or more frequency drift values of the one or more frequency drift values, and the second part including a second one or more frequency drift values of the one or more frequency drift values.

Aspect 23: The method of Aspect 22, wherein the first part includes at least one of: an indication of an anchor CSI-RS resource set from the multiple CSI-RS resource sets, or one or more index values of CSI-RS resource sets associated with the first one or more frequency drift values.

Aspect 24: The method of any of Aspects 22-23, wherein the second part includes one or more index values of CSI-RS resource sets associated with the second one or more frequency drift values.

Aspect 25: The method of any of Aspects 1-24, wherein the CSI configuration includes a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for the frequency drift reporting and at least one of timing offset reporting or phase offset reporting.

Aspect 26: The method of any of Aspects 1-25, wherein the CSI configuration indicates that the multiple CSI-RS resource sets are configured for at least one of timing offset reporting or phase offset reporting, the method further comprising: receiving downlink control information that indicates that the CSI report is to include the one or more frequency drift values and at least one of one or more timing offset values or one or more phase offset values.

Aspect 27: The method of Aspect 26, wherein there is an association between: CSI-RS resources measured for the one or more timing offset values or the one or more phase offset values, and the respective pairs of CSI-RS resource sets.

Aspect 28: The method of any of Aspects 26-27, wherein the CSI report includes an indication of CSI-RS resource sets, from the multiple CSI-RS resource sets, that are associated with the one or more frequency drift values, the one or more timing offset values, or the one or more phase offset values.

Aspect 29: The method of any of Aspects 1-28, further comprising: receiving configuration information for one or more downlink reference signals that are associated with the frequency drift reporting, wherein the one or more frequency drift values are associated with the respective pairs of CSI-RS resource sets and the one or more downlink reference signals.

Aspect 30: The method of any of Aspects 1-29, wherein the multiple CSI-RS resource sets are associated with respective transmission reception points (TRPs) for a coherent joint transmission multi-TRP deployment.

Aspect 31: A method of wireless communication by a network node, comprising: transmitting a channel state information (CSI) configuration indicating multiple CSI reference signal (CSI-RS) resource sets that are configured for frequency drift reporting; and receiving, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.

Aspect 32: The method of Aspect 31, wherein the CSI configuration includes a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for the frequency drift reporting.

Aspect 33: The method of any of Aspects 31-32, wherein the multiple CSI-RS resource sets include an anchor CSI-RS resource set, and the one or more frequency drift values indicate frequency drift differences associated with the anchor CSI-RS resource set and respective CSI-RS resource sets from the multiple CSI-RS resource sets.

Aspect 34: The method of Aspect 33, wherein the CSI configuration indicates the anchor CSI-RS resource set.

Aspect 35: The method of any of Aspects 33-34, wherein the CSI report includes the one or more frequency drift values ordered in accordance with index values of the respective CSI-RS resource sets.

Aspect 36: The method of any of Aspects 33-35, wherein the CSI report includes the one or more frequency drift values ordered in accordance with signal parameter measurements of the respective CSI-RS resource sets.

Aspect 37: The method of Aspect 36, wherein the CSI report includes the signal parameter measurements.

Aspect 38: The method of any of Aspects 33-37, wherein the one or more frequency drift values are a subset of frequency drift values from a set of frequency drift values, and the respective CSI-RS resource sets are a subset of CSI-RS resource sets of the multiple CSI-RS resource sets.

Aspect 39: The method of Aspect 38, wherein the subset of frequency drift values are selected using a comparison of the set of frequency drift values.

Aspect 40: The method of any of Aspects 38-39, wherein the subset of frequency drift values are selected in accordance with signal parameter measurements of the respective CSI-RS resource sets.

Aspect 41: The method of any of Aspects 38-40, wherein the subset of frequency drift values are selected in accordance with signal parameter differences of the respective CSI-RS resource sets.

Aspect 42: The method of any of Aspects 33-41, wherein the anchor CSI-RS resource set is associated with a highest signal parameter measurement from signal parameter measurements of the respective CSI-RS resource sets.

Aspect 43: The method of any of Aspects 33-42, wherein the anchor CSI-RS resource set is selected in accordance with index values of the respective CSI-RS resource sets.

Aspect 44: The method of any of Aspects 33-43, wherein the CSI report includes an indication of the anchor CSI-RS resource set.

Aspect 45: The method of any of Aspects 31-44, wherein the CSI configuration indicates the respective pairs of CSI-RS resource sets.

Aspect 46: The method of any of Aspects 31-45, wherein the CSI report includes the one or more frequency drift values ordered in accordance with index values of the respective pairs of CSI-RS resource sets.

Aspect 47: The method of any of Aspects 31-46, wherein the CSI report includes the one or more frequency drift values ordered in accordance with signal parameter measurements of the respective pairs of CSI-RS resource sets.

Aspect 48: The method of any of Aspects 31-47, wherein the one or more frequency drift values are a subset of frequency drift values from a set of frequency drift values.

Aspect 49: The method of Aspect 48, wherein the subset of frequency drift values are selected using a comparison of the set of frequency drift values.

Aspect 50: The method of any of Aspects 48-49, wherein the subset of frequency drift values are selected in accordance with signal parameter measurements of the respective pairs of CSI-RS resource sets.

Aspect 51: The method of any of Aspects 48-50, wherein the subset of frequency drift values are selected in accordance with signal parameter differences of the respective pairs of CSI-RS resource sets.

Aspect 52: The method of any of Aspects 31-51, wherein the CSI report includes a first part and a second part, the first part indicating a quantity of the one or more frequency drift values and a first one or more frequency drift values of the one or more frequency drift values, and the second part including a second one or more frequency drift values of the one or more frequency drift values.

Aspect 53: The method of Aspect 52, wherein the first part includes at least one of: an indication of an anchor CSI-RS resource set from the multiple CSI-RS resource sets, or one or more index values of CSI-RS resource sets associated with the first one or more frequency drift values.

Aspect 54: The method of any of Aspects 52-53, wherein the second part includes one or more index values of CSI-RS resource sets associated with the second one or more frequency drift values.

Aspect 55: The method of any of Aspects 31-54, wherein the CSI configuration includes a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for the frequency drift reporting and at least one of timing offset reporting or phase offset reporting.

Aspect 56: The method of any of Aspects 31-55, wherein the CSI configuration indicates that the multiple CSI-RS resource sets are configured for at least one of timing offset reporting or phase offset reporting, the method further comprising: transmitting downlink control information that indicates that the CSI report is to include the one or more frequency drift values and at least one of one or more timing offset values or one or more phase offset values.

Aspect 57: The method of Aspect 56, wherein there is an association between: CSI-RS resources measured for the one or more timing offset values or the one or more phase offset values, and the respective pairs of CSI-RS resource sets.

Aspect 58: The method of any of Aspects 56-57, wherein the CSI report includes an indication of CSI-RS resource sets, from the multiple CSI-RS resource sets, that are associated with the one or more frequency drift values, the one or more timing offset values, or the one or more phase offset values.

Aspect 59: The method of any of Aspects 31-58, further comprising: transmitting configuration information for one or more downlink reference signals that are associated with the frequency drift reporting, wherein the one or more frequency drift values are associated with the respective pairs of CSI-RS resource sets and the one or more downlink reference signals.

Aspect 60: The method of any of Aspects 31-59, wherein the multiple CSI-RS resource sets are associated with respective transmission reception points (TRPs) for a coherent joint transmission multi-TRP deployment.

Aspect 61: An apparatus for wireless communication at a device, the apparatus comprising one or more processors; one or more memories coupled with the one or more processors; and instructions stored in the one or more memories and executable by the one or more processors to cause the apparatus to perform the method of one or more of Aspects 1-60.

Aspect 62: An apparatus for wireless communication at a device, the apparatus comprising one or more memories and one or more processors coupled to the one or more memories, the one or more processors configured to cause the device to perform the method of one or more of Aspects 1-60.

Aspect 63: An apparatus for wireless communication, the apparatus comprising at least one means for performing the method of one or more of Aspects 1-60.

Aspect 64: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by one or more processors to perform the method of one or more of Aspects 1-60.

Aspect 65: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more of Aspects 1-60.

Aspect 66: A device for wireless communication, the device comprising a processing system that includes one or more processors and one or more memories coupled with the one or more processors, the processing system configured to cause the device to perform the method of one or more of Aspects 1-60.

Aspect 67: An apparatus for wireless communication at a device, the apparatus comprising one or more memories and one or more processors coupled to the one or more memories, the one or more processors individually or collectively configured to cause the device to perform the method of one or more of Aspects 1-60.

The foregoing disclosure provides illustration and description but is not intended to be exhaustive or to limit the aspects to the precise forms disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects.

As used herein, the term “component” is intended to be broadly construed as hardware or a combination of hardware and at least one of software or firmware. “Software” shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, or functions, among other examples, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. As used herein, a “processor” is implemented in hardware or a combination of hardware and software. It will be apparent that systems or methods described herein may be implemented in different forms of hardware or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems or methods is not limiting of the aspects. Thus, the operation and behavior of the systems or methods are described herein without reference to specific software code, because those skilled in the art will understand that software and hardware can be designed to implement the systems or methods based, at least in part, on the description herein. A component being configured to perform a function means that the component has a capability to perform the function, and does not require the function to be actually performed by the component, unless noted otherwise.

As used herein, “satisfying a threshold” may, depending on the context, refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, or not equal to the threshold, among other examples.

As used herein, a phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a + b, a + c, b + c, and a + b + c, as well as any combination with multiples of the same element (for example, a + a, a + a + a, a + a + b, a + a + c, a + b + b, a + c + c, b + b, b + b + b, b + b + c, c + c, and c + c + c, or any other ordering of a, b, and c) .

As used herein, the term “determine” or “determining” encompasses a wide variety of actions and, therefore, “determining” can include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, a database or another data structure) , inferring, ascertaining, and/or measuring, among other examples. Also, “determining” can include receiving (such as receiving information) , accessing (such as accessing data stored in memory) , and/or transmitting (such as transmitting information) , among other examples. Also, “determining” can include resolving, selecting, obtaining, choosing, establishing and other such similar actions.

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items and may be used interchangeably with “one or more. ” Further, as used herein, the article “the” is intended to include one or more items referenced in connection with the article “the” and may be used interchangeably with “the one or more. ” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items and may be used interchangeably with “one or more. ” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used herein, the terms “has, ” “have, ” “having, ” and similar terms are intended to be open-ended terms that do not limit an element that they modify (for example, an element “having” A may also have B) . Further, the phrase “based on” is intended to mean “based on or otherwise in association with” unless explicitly stated otherwise. Also, as used herein, the term “or” is intended to be inclusive when used in a series and may be used interchangeably with “and/or, ” unless explicitly stated otherwise (for example, if used in combination with “either” or “only one of” ) . It should be understood that “one or more” is equivalent to “at least one. ”

Even though particular combinations of features are recited in the claims or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. Many of these features may be combined in ways not specifically recited in the claims or disclosed in the specification. The disclosure of various aspects includes each dependent claim in combination with every other claim in the claim set.

Claims

A user equipment (UE) for wireless communication, comprising:

a processing system that includes one or more processors and one or more memories coupled with the one or more processors, the processing system configured to cause the UE to:

receive, from a network node, a channel state information (CSI) configuration indicating multiple CSI reference signal (CSI-RS) resource sets that are configured for frequency drift reporting; and

transmit, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.
The UE of claim 1, wherein the CSI configuration includes a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for the frequency drift reporting.
The UE of claim 1, wherein the multiple CSI-RS resource sets include an anchor CSI-RS resource set, and the one or more frequency drift values indicate frequency drift differences associated with the anchor CSI-RS resource set and respective CSI-RS resource sets from the multiple CSI-RS resource sets.
The UE of claim 3, wherein the anchor CSI-RS resource set is selected in accordance with index values of the respective CSI-RS resource sets.
The UE of claim 3, wherein the CSI configuration indicates the anchor CSI-RS resource set.
The UE of claim 3, wherein the CSI report includes an indication of the anchor CSI-RS resource set.
The UE of claim 1, wherein the CSI report includes the one or more frequency drift values ordered in accordance with index values of the respective CSI-RS resource sets.
The UE of claim 1, wherein the CSI report includes the one or more frequency drift values ordered in accordance with signal parameter measurements of the respective CSI-RS resource sets.
The UE of claim 1, wherein the one or more frequency drift values are a subset of frequency drift values from a set of frequency drift values, and the respective CSI-RS resource sets are a subset of CSI-RS resource sets of the multiple CSI-RS resource sets.
The UE of claim 1, wherein the CSI report includes the one or more frequency drift values ordered in accordance with index values of the respective pairs of CSI-RS resource sets.
The UE of claim 1, wherein the CSI report includes the one or more frequency drift values ordered in accordance with signal parameter measurements of the respective pairs of CSI-RS resource sets.
The UE of claim 1, wherein the one or more frequency drift values are a subset of frequency drift values from a set of frequency drift values.
The UE of claim 12, wherein the subset of frequency drift values are selected in accordance with signal parameter measurements of the respective pairs of CSI-RS resource sets.
The UE of claim 12, wherein the subset of frequency drift values are selected in accordance with signal parameter differences of the respective pairs of CSI-RS resource sets.
The UE of claim 1, wherein the CSI report includes a first part and a second part, the first part indicating a quantity of the one or more frequency drift values and a first one or more frequency drift values of the one or more frequency drift values, and the second part including a second one or more frequency drift values of the one or more frequency drift values.
A network node for wireless communication, comprising:

a processing system that includes one or more processors and one or more memories coupled with the one or more processors, the processing system configured to cause the network node to:

transmit a channel state information (CSI) configuration indicating multiple CSI reference signal (CSI-RS) resource sets that are configured for frequency drift reporting; and

receive, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.
The network node of claim 16, wherein the multiple CSI-RS resource sets include an anchor CSI-RS resource set, and the one or more frequency drift values indicate frequency drift differences associated with the anchor CSI-RS resource set and respective CSI-RS resource sets from the multiple CSI-RS resource sets.
The network node of claim 17, wherein the CSI report includes the one or more frequency drift values ordered in accordance with signal parameter measurements of the respective CSI-RS resource sets, and wherein the CSI report includes the signal parameter measurements.
The network node of claim 16, wherein the CSI configuration includes a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for the frequency drift reporting and at least one of timing offset reporting or phase offset reporting, wherein CSI-RS resources, for the respective CSI-RS resource sets, to be associated with the timing offset reporting or the phase offset reporting are indicated in association with CSI-RS resource indices of the CSI-RS resources.
The network node of claim 16, wherein the CSI configuration indicates that the multiple CSI-RS resource sets are configured for at least one of timing offset reporting or phase offset reporting, wherein the processing system is further configured to cause the network node to:

transmit downlink control information that indicates that the CSI report is to include the one or more frequency drift values and at least one of one or more timing offset values or one or more phase offset values.
A method of wireless communication by a user equipment (UE) , comprising:

receiving, from a network node, a channel state information (CSI) configuration indicating multiple CSI reference signal (CSI-RS) resource sets that are configured for frequency drift reporting; and

transmitting, to the network node and in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.
The method of claim 21, wherein the CSI report includes a first part and a second part, the first part indicating a quantity of the one or more frequency drift values and a first one or more frequency drift values of the one or more frequency drift values, and the second part including a second one or more frequency drift values of the one or more frequency drift values.
The method of claim 22, wherein the first part includes at least one of:

an indication of an anchor CSI-RS resource set from the multiple CSI-RS resource sets, or

one or more index values of CSI-RS resource sets associated with the first one or more frequency drift values.
The method of claim 22, wherein the second part includes one or more index values of CSI-RS resource sets associated with the second one or more frequency drift values.
The method of claim 21, wherein the CSI configuration includes a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for the frequency drift reporting and at least one of timing offset reporting or phase offset reporting.
The method of claim 21, wherein the CSI configuration indicates that the multiple CSI-RS resource sets are configured for at least one of timing offset reporting or phase offset reporting, the method further comprising:

receiving downlink control information that indicates that the CSI report is to include the one or more frequency drift values and at least one of one or more timing offset values or one or more phase offset values,

wherein there is an association between:

CSI-RS resources measured for the one or more timing offset values or the one or more phase offset values, and

the respective pairs of CSI-RS resource sets.
The method of claim 26, wherein the CSI report includes an indication of CSI-RS resource sets, from the multiple CSI-RS resource sets, that are associated with the one or more frequency drift values, the one or more timing offset values, or the one or more phase offset values.
The method of claim 21, further comprising:

receiving configuration information for one or more downlink reference signals that are associated with the frequency drift reporting, wherein the one or more frequency drift values are associated with the respective pairs of CSI-RS resource sets and the one or more downlink reference signals.
A method of wireless communication by a network node, comprising:

transmitting a channel state information (CSI) configuration indicating multiple CSI reference signal (CSI-RS) resource sets that are configured for frequency drift reporting; and

receiving, in accordance with the CSI configuration, a CSI report indicating one or more frequency drift values that are associated with respective pairs of CSI-RS resource sets from the multiple CSI-RS resource sets.
The method of claim 29, wherein the CSI configuration includes a report quantity setting that indicates that the multiple CSI-RS resource sets are configured for the frequency drift reporting.