WO2025213436A1

WO2025213436A1 - Uplink communication direction based on sounding reference signal

Info

Publication number: WO2025213436A1
Application number: PCT/CN2024/087367
Authority: WO
Inventors: Qing Li; Ruiming Zheng; Junyi Li
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2024-04-12
Filing date: 2024-04-12
Publication date: 2025-10-16
Anticipated expiration: 2026-10-12

Abstract

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit a sounding reference signal (SRS) set in a beam sweep. The UE may receive an indication to transmit an uplink communication toward a transmit receive point (TRP). The UE may transmit the uplink communication toward the TRP based at least in part on the indication. Numerous other aspects are described.

Description

UPLINK COMMUNICATION DIRECTION BASED ON SOUNDING REFERENCE SIGNAL

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and specifically relate to techniques, apparatuses, and methods for indicating an uplink communication direction based on a sounding reference signal.

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.

SUMMARY

Some aspects described herein relate to a method of wireless communication performed by a user equipment (UE) . The method may include transmitting a sounding reference signal (SRS) set in a beam sweep. The method may include receiving an indication to transmit an uplink communication toward a transmit receive point (TRP) . The method may include transmitting the uplink communication toward the TRP based at least in part on the indication.

Some aspects described herein relate to a method of wireless communication performed by a network entity. The method may include receiving, from a TRP, an indication of a selected SRS. The method may include transmitting, to a UE based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP.

Some aspects described herein relate to a method of wireless communication performed by a network entity. The method may include receiving one or more SRSs from a UE. The method may include transmitting an indication of an SRS that is selected based at least in part on a signal strength or quality.

Some aspects described herein relate to an apparatus for wireless communication at a UE. The apparatus may include one or more memories and one or more processors coupled to the one or more memories. The one or more processors may be individually or collectively configured to transmit an SRS set in a beam sweep. The one or more processors may be individually or collectively configured to receive an indication to transmit an uplink communication toward a TRP. The one or more processors may be individually or collectively configured to transmit the uplink communication per the indication toward the TRP based at least in part on the indication.

Some aspects described herein relate to an apparatus for wireless communication at a network entity. The apparatus may include one or more memories and one or more processors coupled to the one or more memories. The one or more processors may be individually or collectively configured to receive, from a TRP, an indication of a selected SRS. The one or more processors may be individually or collectively configured to transmit, to a UE based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP.

Some aspects described herein relate to an apparatus for wireless communication at a network entity. The apparatus may include one or more memories and one or more processors coupled to the one or more memories. The one or more processors may be individually or collectively configured to receive one or more SRSs from a UE. The one or more processors may be individually or collectively configured to transmit, an indication of an SRS that is selected based at least in part on a signal strength or quality.

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 transmit an SRS set in a beam sweep. The set of instructions, when executed by one or more processors of the UE, may cause the UE to receive an indication to transmit an uplink communication toward a TRP. The set of instructions, when executed by one or more processors of the UE, may cause the UE to transmit the uplink communication per the indication toward the TRP based at least in part on the indication.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a network entity. The set of instructions, when executed by one or more processors of the network entity, may cause the network entity to receive, from a TRP, an indication of a selected SRS. The set of instructions, when executed by one or more processors of the network entity, may cause the network entity to transmit, to a UE based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a network entity. The set of instructions, when executed by one or more processors of the network entity, may cause the network entity to receive one or more SRSs from a UE. The set of instructions, when executed by one or more processors of the network entity, may cause the network entity to transmit an indication of an SRS that is selected based at least in part on a signal strength or quality.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for transmitting an SRS set in a beam sweep. The apparatus may include means for receiving an indication to transmit an uplink communication toward a TRP. The apparatus may include means for transmitting the uplink communication toward the TRP based at least in part on the indication.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for receiving, from a TRP, an indication of a selected SRS. The apparatus may include means for transmitting, to another apparatus based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for receiving one or more SRSs from a UE. The apparatus may include means for transmitting an indication of an SRS that is selected based at least in part on a signal strength or quality.

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.

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

Fig. 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.

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

Fig. 4 is a diagram illustrating an example of an uplink dense deployment, in accordance with the present disclosure.

Fig. 5 is a diagram illustrating an example of sounding reference signal (SRS) resource sets, in accordance with the present disclosure.

Fig. 6 is a diagram illustrating an example of SRS based association for indicating a direction for an uplink communication, in accordance with the present disclosure.

Fig. 7 is a diagram illustrating an example of indicating an SRS for uplink communications, in accordance with the present disclosure.

Fig. 8 is a diagram illustrating an example process performed, for example, at a UE or an apparatus of a UE, in accordance with the present disclosure.

Fig. 9 is a diagram illustrating an example process performed, for example, at a network entity or an apparatus of a network entity, in accordance with the present disclosure.

Fig. 10 is a diagram illustrating an example process performed, for example, at a network entity or an apparatus of a network entity, in accordance with the present disclosure.

Fig. 11 is a diagram of an example apparatus for wireless communication, in accordance with the present disclosure.

Fig. 12 is a diagram of an example apparatus for wireless communication, 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.

In order to improve the coverage and capacity of uplink (UL) transmissions, an UL dense deployment may be used. The UL dense deployment may include a macro network entity providing macro coverage and multiple UL receive (Rx) points, such as multiple transmit receive points or multiple transmission and reception points (mTRPs) , providing UL micro coverage. Although the acronym “mTRP” refers to multiple TRPs, “mTRP” can be used in the singular, and when so used, can refer to a single TRP that is among multiple TRPs, within the context of an mTRP environment, providing micro coverage in coordination with a macro network entity. An mTRP that provides micro coverage may be considered a ” micro” mTRP. The mTRPs may be UL-only nodes where only UL signals and channels are received for reception by the network entity. A user equipment (UE) may transmit a signal or message to an UL-only node. Downlink (DL) signals and channels are transmitted from a different node (e.g., macro node, central node or central unit (CU) , serving cell, serving base station) , such as a network entity. The UL Rx points are connected to the network entity via a front haul or backhaul.

A beam may be associated with UL. For UL-only mTRPs, there is no DL reference for UL beam association, and thus the beam association or transmission configuration indicator (TCI) state cannot be based on a DL reference from an UL-only mTRP. Beam association and TCI states have not been addressed for UL-only mTRPs.

Various aspects relate generally to uplink communications. Some aspects more specifically relate to a UE transmitting a sounding reference signal (SRS) burst (e.g., in a beam sweep) that is received by one or more mTRPs. The mTRPs may measure the SRS and report, to a macro network entity, an SRS that may have a strongest signal strength or quality of SRSs received by the mTRP from the UE. The macro network entity may select an SRS and determine a beam or resource (e.g., corresponding to the selected SRS) that a UE is to use for an uplink communication to an mTRP. The macro network entity may transmit an indication of an SRS to the UE based at least in part on the selected SRS. The UE may determine which direction, or toward which mTRP, to transmit an uplink communication based at least in part on the indication (indicated SRS) . The UE may associate the SRS with a beam and/or resource and use the beam and/or resource to transmit the uplink communication to an mTRP (e.g., UL-only mTRP) .

Particular aspects of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. By using an SRS beam sweep and an SRS-associated indication, the UE may transmit an uplink communication to an mTRP using a beam and/or resources that are more optimal than other beams or resources, which improves uplink communications without receiving a downlink communication from the mTRP. As a result, signaling resources are conserved and throughput is increased.

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.

Fig. 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 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 micro 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 micro or 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 Fig. 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 this case, the wireless communication network 100 may include or be referred to as a “multi-hop network. ” In the example shown in Fig. 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, Institute of Electrical and Electronics Engineers (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 (NCJT) .

In some aspects, a UE (e.g., a UE 120) may include a communication manager 140. As described in more detail elsewhere herein, the communication manager 140 may transmit an SRS set in a beam sweep. The communication manager 140 may receive an indication (e.g., from network node 110a) . to transmit an uplink communication toward a transmit receive point (TRP) (e.g., network node 110b or 110c) . The communication manager 140 may transmit the uplink communication toward the TRP based at least in part on the indication. Additionally, or alternatively, the communication manager 140 may perform one or more other operations described herein.

In some aspects, a network entity (e.g., a network node 110a) may include a communication manager 150. As described in more detail elsewhere herein, the communication manager 150 may receive, from a TRP (e.g., a network node 110b or 110c) , an indication of a selected SRS. The communication manager 150 may transmit, to a UE based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP. Additionally, or alternatively, the communication manager 150 may perform one or more other operations described herein.

In some aspects, a network entity (e.g., a network node 110b or 110c) may include a communication manager 160. As described in more detail elsewhere herein, the communication manager 160 may receive one or more SRSs from a UE. The communication manager 160 may transmit, an indication of an SRS that is selected based at least in part on a signal strength or quality. Additionally, or alternatively, the communication manager 160 may perform one or more other operations described herein.

As indicated above, Fig. 1 is provided as an example. Other examples may differ from what is described with regard to Fig. 1.

Fig. 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 Fig. 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 or 160, 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 Fig. 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 Fig. 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 Fig. 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 Fig. 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 numbers 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 number 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 number of antenna elements. Generally, a larger number of antenna elements may provide increased control over parameters for beam generation relative to a smaller number of antenna elements, whereas a smaller number of antenna elements may be less complex to implement and may use less power than a larger number 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.

While blocks in Fig. 2 are illustrated as distinct components, the functions described above with respect to the blocks may be implemented in a single hardware, software, or combination component or in various combinations of components. For example, the functions described with respect to the transmit processor 264, the receive processor 258, and/or the TX MIMO processor 266 may be performed by or under the control of the controller/processor 280.

Fig. 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 indicated above, Fig. 3 is provided as an example. Other examples may differ from what is described with regard to Fig. 3.

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 Figs. 1, 2, or 3 may implement one or more techniques or perform one or more operations associated with indicating an uplink communication direction based on an SRS, 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 Fig. 2, the CU 310, the DU 330, or the RU 340 may perform or direct operations of, for example, process 800 of Fig. 8, process 900 of Fig. 9, process 1000 of Fig. 10, 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 800 of Fig. 8, process 900 of Fig. 9, process 1000 of Fig. 10, 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, a UE (e.g., a UE 120) includes means for transmitting an SRS set in a beam sweep (e.g., using controller/processor 280, transmit processor 264, TX MIMO processor 266, modem 254, antenna 252, memory 282, and/or the like) ; means for receiving an indication to transmit an uplink communication toward a TRP (e.g., using antenna 252, modem 254, MIMO detector 256, receive processor 258, controller/processor 280, memory 282, and/or the like) ; and/or means for transmitting the uplink communication toward the TRP based at least in part on the indication (e.g., using controller/processor 280, transmit processor 264, TX MIMO processor 266, modem 254, antenna 252, memory 282, and/or the like) . The means for the UE 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, a network entity (e.g., a network node 110) includes means for receiving, from a TRP, an indication of a selected SRS (e.g., using antenna 234, modem 232, MIMO detector 236, receive processor 238, controller/processor 240, memory 242, and/or the like) ; and/or means for transmitting, to a UE based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP (e.g., using controller/processor 240, transmit processor 214, TX MIMO processor 216, modem 232, antenna 234, memory 242, and/or the like) . In some aspects, the means for the network entity to perform operations described herein may include, for example, one or more of communication manager 150 or 160, 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.

In some aspects, a network entity (e.g., a network node 110) includes means for receiving one or more SRSs from a UE (e.g., using antenna 234, modem 232, MIMO detector 236, receive processor 238, controller/processor 240, memory 242, and/or the like) ; and/or means for transmitting an indication of an SRS that is selected based at least in part on a signal strength or quality (e.g., using controller/processor 240, transmit processor 214, TX MIMO processor 216, modem 232, antenna 234, memory 242, and/or the like) . In some aspects, the means for the network entity to perform operations described herein may include, for example, one or more of communication manager 150 or 160, 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.

Fig. 4 is a diagram illustrating an example 400 of an UL dense deployment, in accordance with the present disclosure.

In order to improve the coverage and capacity of UL transmissions, an UL dense deployment may be used. As shown by example 400, the UL dense deployment may include a network entity 405 providing macro coverage and multiple UL receive (Rx) points, shown by mTRP k 410 and mTRP l 415, providing UL micro coverage. The mTRPs may be UL-only nodes where only UL signals and channels are received for reception by the network entity 405. A UE 420 (or UE 425) may transmit a message to an UL-only node. DL signals and channels are transmitted from a different node (e.g., macro node, central node, serving cell, serving base station, or CU) , such as the network entity 405. The UL Rx points are connected to the network entity 405 via a backhaul.

The UL dense deployment reduces the UL path loss, which is helpful when UL coverage is the bottleneck. The UL dense deployment can also help with deployment costs and complexity because the UL Rx points do not transmit any DL signals. The UL Rx points are expected to just receive an UL signal or message and transmit the UL signal or message to the macro node, with or without some processing.

Example 400 shows that a beam associated with UL may be based on a DL synchronization signal block (SSB) selected by the UE 420, and thus a TCI state is rooted at the selected SSB (e.g., TCI 1) . For UL-only mTRPs, there is no DL reference (i.e., no SSB or CSI-RS/tracking refence signal (TRS) transmissions) for UL beam association, and thus the beam association or TCI state (e.g., TCI 2) cannot be based on a DL reference, such as the selected SSB. Beam association and TCI states have not been addressed for UL-only mTRPs.

As indicated above, Fig. 4 is provided as an example. Other examples may differ from what is described with regard to Fig. 4.

Fig. 5 is a diagram illustrating an example 500 of SRS resource sets, in accordance with the present disclosure.

UL dense deployments may include network entities that receive SRSs from a UE (e.g., UE 425) . The UE 425 may be configured with one or more SRS resource sets to allocate resources for SRS transmissions by the UE 425. For example, a configuration for SRS resource sets may be indicated in a radio resource control (RRC) message (e.g., an RRC configuration message or an RRC reconfiguration message) . As shown by reference number 505, an SRS resource set may include one or more resources (e.g., shown as SRS resources) , which may include time resources and/or frequency resources (e.g., a slot, a symbol, a resource block, and/or a periodicity for the time resources) .

As shown by reference number 510, an SRS resource may include one or more antenna ports on which an SRS is to be transmitted (e.g., in a time-frequency resource) . Thus, a configuration for an SRS resource set may indicate one or more time-frequency resources in which an SRS is to be transmitted, and may indicate one or more antenna ports on which the SRS is to be transmitted in those time-frequency resources. In some aspects, the configuration for an SRS resource set may indicate a use case (e.g., in an SRS-SetUse information element) for the SRS resource set. For example, an SRS resource set may have a use case of antenna switching, codebook, non-codebook, or beam management.

An antenna switching SRS resource set may be used to indicate downlink CSI with reciprocity between an uplink and downlink channel. For example, when there is reciprocity between an uplink channel and a downlink channel, the network entity 405 may use an antenna switching SRS (e.g., an SRS transmitted using a resource of an antenna switching SRS resource set) to acquire downlink CSI (e.g., to determine a downlink precoder to be used to communicate with the UE 425) .

A codebook SRS resource set may be used to indicate uplink CSI when the network entity 405 indicates an uplink precoder to the UE 425. For example, when the network entity 405 is configured to indicate an uplink precoder to the UE 425 (e.g., using a precoder codebook) , the network entity 405 may use a codebook SRS (e.g., an SRS transmitted using a resource of a codebook SRS resource set) to acquire uplink CSI (e.g., to determine an uplink precoder to be indicated to the UE 425 and used by the UE 425 to communicate with the network entity 405) . In some aspects, virtual ports (e.g., a combination of two or more antenna ports) with a maximum transmit power may be supported at least for a codebook SRS.

A non-codebook SRS resource set may be used to indicate uplink CSI when the UE 425 selects an uplink precoder (e.g., instead of the network entity 405 indicating an uplink precoder to be used by the UE 425) . For example, when the UE 425 is configured to select an uplink precoder, the network entity 405 may use a non-codebook SRS (e.g., an SRS transmitted using a resource of a non-codebook SRS resource set) to acquire uplink CSI. In this case, the non-codebook SRS may be precoded using a precoder selected by the UE 425 (e.g., which may be indicated to the network entity 405) . A beam management SRS resource set may be used for indicating CSI for millimeter wave communications.

An SRS resource can be configured as periodic, semi-persistent (sometimes referred to as semi-persistent scheduling (SPS) ) , or aperiodic. A periodic SRS resource may be configured via a configuration message that indicates a periodicity of the SRS resource (e.g., a slot-level periodicity, where the SRS resources occurs every Y slots) and a slot offset. In some cases, a periodic SRS resource may always be activated, and may not be dynamically activated or deactivated. A semi-persistent SRS resource may also be configured via a configuration message that indicates a periodicity and a slot offset for the semi-persistent SRS resource, and may be dynamically activated and deactivated (e.g., using DCI or a MAC-CE) . An aperiodic SRS resource may be triggered dynamically, such as via DCI (e.g., UE-specific DCI or group common DCI) or a MAC-CE.

In some aspects, the UE 425 may be configured with a mapping between SRS ports (e.g., antenna ports) and corresponding SRS resources. The UE 425 may transmit an SRS on a particular SRS resource using an SRS port indicated in the configuration. In some aspects, an SRS resource may span N adjacent symbols within a slot (e.g., where N equals 1, 2, or 4) . The UE 425 may be configured with X SRS ports (e.g., where X ≤ 4) . In some aspects, each of the X SRS ports may be mapped to a corresponding symbol of the SRS resource and used for transmission of an SRS in that symbol.

As shown in Fig. 5, in some aspects, different SRS resource sets indicated to the UE 425 (e.g., having different use cases) may overlap (e.g., in time and/or in frequency, such as in the same slot) . For example, as shown by reference number 515, a first SRS resource set (e.g., shown as SRS Resource Set 1) is shown as having an antenna switching use case. As shown, this example antenna switching SRS resource set includes a first SRS resource (shown as SRS Resource A) and a second SRS resource (shown as SRS Resource B) . Thus, an antenna switching SRS may be transmitted in SRS Resource A (e.g., a first time-frequency resource) using antenna port 0 and antenna port 1 and may be transmitted in SRS Resource B (e.g., a second time-frequency resource) using antenna port 2 and antenna port 3.

As shown by reference number 520, a second SRS resource set (e.g., shown as SRS Resource Set 2) may be a codebook use case. As shown, this example codebook SRS resource set includes only the first SRS resource (shown as SRS Resource A) . Thus, codebook SRSs may be transmitted in SRS Resource A (e.g., the first time-frequency resource) using antenna port 0 and antenna port 1. In this case, the UE 120 may not transmit codebook SRSs in SRS Resource B (e.g., the second time-frequency resource) using antenna port 2 and antenna port 3.

As indicated above, Fig. 5 is provided as an example. Other examples may differ from what is described with regard to Fig. 5.

Fig. 6 is a diagram illustrating an example 600 of SRS based association for indicating a direction for an uplink communication, in accordance with the present disclosure.

According to various aspects described herein, a UE may transmit an SRS burst (e.g., in a beam sweep) that is received by one or more mTRPs. The mTRPs may measure one or more of the SRSs. Each mTRP may report, to a macro network entity, an SRS that has a strongest signal strength or quality of SRSs received by the mTRP from the UE. Each mTRP may report one or more SRSs that have a signal strength or quality above a threshold among the SRSs received by the mTRP from the UE or one or more measurements of SRSs received by the mTRP from the UE. The macro network entity may select an mTRP based on the received reports from mTRPs and an SRS associated to the selected mTRP and indicate the SRS that associates with a beam or resource that a UE is to use for an uplink communication toward an mTRP (in a direction of the selected mTRP) . The macro network entity may transmit an indication of the SRS to the UE. The UE may determine which direction, or to which mTRP, to transmit an uplink communication based at least in part on the indicated SRS. The UE may associate the SRS with a beam and/or resource and use the beam and/or resource to transmit the uplink communication to an mTRP (e.g., UL-only mTRP) . By using an SRS beam sweep and an SRS-associated indication, the UE may transmit an uplink communication to an mTRP using a beam and/or resources that are more optimal than other beams or resources, which improves uplink communications without receiving a downlink communication from the mTRP. As a result, signaling resources are conserved and throughput is increased.

The UE may receive a configuration that indicates one or more SRS sets for sweeping SRSs in one or more SRS bursts. For example, the configuration may include a first SRS set for sweeping the uplink beams from a first antenna panel and a second SRS set for sweeping the uplink beams from a second antenna panel, or an SRS set for sweeping the UL beams from both a first antenna panel and a second antenna panel.

Example 600 shows an SRS set (SRS burst i) of N SRS resources that a UE transmits as part of an SRS beam sweep. Both mTRP k and mTRP l may receive one or more SRSs. After measuring SRSs, mTRP k may select SRS k, and mTRP l may select SRS l as being the best SRSs received from the UE during the SRS beam sweep. The selected SRS k may be used for uplink communications to mTRP k. The selected SRS l may be used for uplink communications to mTRP l. The mTRPs may report the selected SRSs to a macro network entity. Additionally or alternatively, the mTRPs may report measurements (e.g., RSSI, RSRP, or RSRQ) of the SRSs received from the UE during the SRS beam sweep.

The macro network entity may select an mTRP and a beam (direction) and/or resources associated with a selected SRS for the UE to use for uplink communications based at least in part on the selected SRSs indicated by the mTRPs. The macro network entity may transmit, to mTRP k and/or mTRP l, an indication of an SRS that is associated with the selected beam and/or resources for the UE to use for uplink communications. The indication may be for uplink communications from the UE to either mTRP k and/or mTRP l, semi-statically configured via RRC message (s) or dynamically indicated via DCI (s) , based at least in part on the association with the selected SRSs, respectively (e.g., SRS k and/or SRS l) . The uplink communications may include PUCCH transmissions, PUSCH transmissions, and/or dedicated PRACH transmissions.

The UE may receive the indication, select the beam and/or resources associated with the indicated SRS, and transmit an uplink communication using the selected beam and/or resources. As the UE is aware of the beam direction and/or resources used for the indicated SRS, no other signaling is necessary to indicate the direction in which the UE is to transmit an uplink communication to an mTRP.

Example 600 shows that the uplink communication may be a PUCCH message (PUCCH k or scheduling request (SR) k) , a PUSCH message (PUSCH k) , or a PRACH message (PRACH k) associated with an SRS k indicated by the macro network entity. The UE may transmit the PUCCH message, the PUSCH message, or the PRACH message toward mTRP k. Example 600 also shows that the uplink communication may be a PUCCH message (PUCCH l or SR l) or a PUSCH message (PUSCH l) associated with an SRS l indicated by the macro network entity.

In some aspects, the indication may be for a PUCCH message that is associated with an SRS indicated in the SRS indication. An SRS-based association may be indicated via an SRS indication of an SRS set or an SRS burst (e.g., an SRS ID, an SRS index, an SRS resource ID, or an SRS resource index of one or multiple SRS bursts) for PUCCH transmissions on one or more UL-only mTRPs. The indication may be included in PUCCH spatial relation information (e.g., a spatial relation information element (IE) ) . In some aspects, the indication may be included in an RRC configuration. A PUCCH (for DL hybrid automatic repeat request (HARQ) feedback or an SR) may be configured with the PUCCH spatial relation information (e.g., PUCCH-SpacialRelationInfo-ULmTRP) referenced from the selected SRS for UL-only mTRPs (e.g., under referenceSignal-ULmTRP with srs_ULmTRP set with ULmTRP-SRS_ID k, ULmTRP-SRS_Index l, ULmTRP-SRS_Resource_ID k, or ULmTRP-SRS_Resource_Index l of SRS_Burst i for mTRP k or mTRP l, respectively) . In some aspects, the indication may be included in DCI. A macro network entity may include a new field (e.g., ULmTRP indicator) in DCI. For example, the ULmTRP indicator may equal “1” in a DCI format 1 for PUCCH transmissions on UL-only mTRPs. In some aspects, the macro network entity may indicate whether the UE is to transmit an uplink communication to an mTRP (e.g., ULmTRP indicator is “1” ) or to the macro network entity (e.g., ULmTRP indicator is “0” ) .

In some aspects, a macro network entity may include a new field (e.g., ULmTRP indicator) in DCI for a PUSCH transmission. For example, the ULmTRP indicator may equal “1” in a DCI format 0 for PUSCH transmissions on UL-only mTRPs. In some aspects, the macro network entity may indicate whether the UE is to transmit an uplink communication to an mTRP (e.g., ULmTRP indicator is “1” ) or to the macro network entity (e.g., ULmTRP indicator is “0” ) .

In some aspects, a macro network entity may include a new field (e.g., ULmTRP indicator) in DCI for an SRS transmission. For example, the ULmTRP indicator may equal “1” in a DCI format 0 or 1 for SRS transmissions specifically on UL-only mTRPs (e.g., non-burst SRS k’ transmissions dedicated to mTRP k) . In some aspects, the macro network entity may indicate whether the UE is to transmit an uplink SRS to an mTRP (e.g., ULmTRP indicator is “1” ) or to the macro network entity (e.g., ULmTRP indicator is “0” ) .

In some aspects, the indication may be for a PUSCH message that is associated with an SRS indicated in the SRS indication. An SRS-based association may be indicated via an SRS indication of an SRS set or an SRS burst (e.g., an SRS ID, SRS index, SRS resource ID, or SRS resource index of one or multiple SRS bursts) for PUSCH transmissions on one or more UL-only mTRPs. The indication may be included in SRS resource information, such as in an SRS resource indicator for non-codebook or codebook-based transmissions. In some aspects, the indication may be in an RRC configuration. The RRC configuration may include a configured parameter srs-ResourceIndicator (used for txConfig = nonCodebook or txConfig = Codebook based PUSCH transmissions) associated with an SRS indication of an SRS set or a selected SRS of an SRS burst (e.g., ULmTRP-SRS_ID k, ULmTRP-SRS_Index l, ULmTRP-SRS_Resource_ID k, ULmTRP-SRS_Resource_Index l of one or multiple SRS bursts, such as an SRS_Burst i for UL-only mTRPs) . In some aspects, the indication may be included in DCI. For example, the DCI may include a field (e.g., SRS resource indicator (SRI) ) in DCI format 0 (for txConfig=nonCodebook or txConfig=Codebook based PUSCH transmissions) associated with an SRS indication of an SRS set or a selected SRS of an SRS burst (e.g., ULmTRP-SRS_ID k, ULmTRP-SRS_Index l, ULmTRP-SRS_Resource_ID k, or ULmTRP-SRS_Resource_Index l of one or multiple SRS bursts, such as an SRS_Burst i for ULmTRPs) . The configuration may indicate the number of configured SRS resources or SRS beams in an SRS resource set for an SRS burst.

In some aspects, for a non-codebook based PUSCH communication, the indication may be semi-statically configured via RRC or dynamically indicated via DCI. The UE may determine the precoder and/or rank for the uplink MIMO transmission based at least in part on the adjusted measurement on a CSI-RS (e.g., the measurements of non-zero power (NZP) CSI-RSs configured via RRC or indicated via DCI may be adjusted with an offset such as offset_mTRPk or offset_mTRPl for mTRPk or mTRPl, respectively) . Additionally or alternatively, the UE may determine the precoder and/or rank for the uplink MIMO transmission based at least in part on adjusted pathloss measurements for the selected SRS (e.g., pathloss ULmTRP_pl_SRSk, ULmTRP_pl_SRSk for mTRPk, or mTRPl, respectively) .

In some aspects, the UE may determine the transmit power for the uplink transmission on an UL beam associated with the SRS indication (e.g., PUCCH k, PUSCH k, PRACH k, or SRS k’ (non-burst) to mTRP k or PUCCH l, PUSCH l, PRACH l, or SRS l’ (non-burst) to mTRP l) based on the downlink measurements (e.g., SSB or CSI-RS from the macro network entity) and/or the corresponding offset (e.g., offset for SSB measurement, offset for NZP CSI-RS measurement, offset for the DL path loss, or offset from the transmit power of the SRS or PRACH transmission on an uplink beam to the macro network entity) .

In some aspects, the indication may be for a dedicated PRACH message that is associated with an SRS indicated in the SRS indication. An SRS-based association may be indicated via an SRS indication of an SRS set or an SRS burst for PRACH transmissions on one or more UL-only mTRPs. In some aspects, the indication may be included in a dedicated or contention-free PRACH configuration. In some aspects, the indication may indicate an mTRP for PRACH.

In some aspects, the PRACH configuration may include SRS resource information. The SRS resource information may include one or more SRS resources or a beam direction of the PRACH associated with the SRS resource information. For example, an RRC configuration for RACH on an UL-only mTRP (e.g., RACH-ConfigDedicated-ULmTRP) containing CFRA configuration for the UL-only mTRP (e.g., CFRA-ULmTRP and/or CFRA-TwoStep-r16-ULmTRP) may include an indication of an SRS in fields such as srs-perRACH-Occasion-ULmTRP under the IE occasions-ULmTRP, srs-ULmTRP (SRS associated with the UL-only mTRP) (e.g., srs-ResourceList-ULmTRP, ra-srs-OccasionMaskIndex-ULmTRP) or csirs-ULmTRP (CSI-RS on DL used or referenced for the UL-only mTRP) (e.g., csirs-ResourceList-ULmTRP, rsrp-ThresholdCSI-RS-ULmTRP, or rsrp-ThresholdCSI-RS-ULmTRP-Offset) under the IE resources-ULmTRP. In some aspects, the indication of the SRS may be in RRC configuration fields for CFRA SRS based resources (e.g., associated with one or more SRSs for an UL-only mTRP srs-ResourceList-ULmTRP) such as CFRA-SRS-Resource-ULmTRP (e.g., with srs-ULmTRP (containing ULmTRP-SRS_ID or ULmTRP-SRS_Index for an SRS on the UL-only mTRP) , ra-OccasionList-srsULmTRP and/or ra-PreambleIndex-srsULmTRP) associated with the srs-ULmTRP) or CFRA-CSIRS-Resource-ULmTRP (e.g., with csi-RS-ULmTRP, ra-OccasionList-ULmTRP and/or ra-PreambleIndex-ULmTRP associated with the csi-RS-ULmTR (e.g., the CI-RS on DL used or referenced for the UL-only mTRP) ) .

In some aspects, the SRS based association may be indicated via an SRS indication of an SRS set or an SRS burst for PRACH transmissions on one or more UL-only mTRPs. The indication may be for dedicated or contention-free PRACH transmissions. In some aspects, the indication may be included in a DCI order-based PRACH message that includes a new field (e.g., ULmTRP indicator) , where the ULmTRP indicator may be 1 in format DCI (e.g., DCI 1_0) based at least in part on a PRACH on UL-only mTRPs. In some aspects, the macro network entity may repurpose the DCI field SS/PBCH index (e.g., in DCI 1_0) as ULmTRP-SRS_ID, ULmTRP-SRS_Index, ULmTRP-SRS_Resource_ID, or ULmTRP-SRS_Resource_Index when the ULmTRP indicator field is set as “1” .

In some aspects, the indication of the SRS may include an SRS-based uplink TCI state. An SRS-based association may be indicated via a new UL TCI state indication associated with the selected SRS of an SRS set or an SRS burst (e.g., SRS-based UL TCI state) using a unified TCI framework. The TCI state indication may include a separate TCI state model for a DL transmission from the macro network entity (e.g., referenced as sTRP 705 in Figure 7) and/or an UL transmission to an UL-only mTRP (e.g., referenced as mTRP 710 or mTRP 715 in Figure 7) . Additionally or alternatively, the TCI state indication may include more than one UL transmission on UL-only mTRPs, respectively. The indication may be included in a new UL TCI state (e.g., configured in tci-StateToAddModList or activated by MAC CE) which may be referenced from or associated with an SRS of an SRS burst (e.g., SRS k based UL TCI state tci-StateId s3 with “referenceSignal srs: k” and “qcl-Type = TypeC” or “qcl-Type = TypeD” for UL transmissions to UL-only mTRP k or SRS j based UL TCI state tci-StateId s4 with “referenceSignal srs: l” and “qcl-Type = TypeC” or “qcl-Type = TypeD” for UL transmissions to UL only mTRP k) . In some aspects, a code point of the TCI state table (e.g., configured via RRC tci-StateToAddModList and activated via MAC-CE) may be indicated via the transmission configuration indication field in DCI (e.g., DCI 1_1, DCI 1_2, and DCI 1_3) using the unified TCI framework.

In some aspects, an example of a unified TCI framework with the new UL TCI state may include DCI that contains the code point of tci-StateId s1 (e.g., with “referenceSignal ssb: i” ) for DL transmission (s) from the sTRP and/or the code point of tci-StateId s2 (e.g., with “referenceSignal csi-rs: j” ) for UL transmission (s) to the sTRP. Another example of a unified TCI framework may include DCI that contains the code point of tci-StateId s1 for DL transmission (s) on the sTRP and/or the code point of tci-StateId s3 /tci-StateId s4 for UL transmission (s) on the mTRP k /mTRP l. In yet another example, a unified TCI framework may include DCI that contains the code point of tci-StateId s3 for UL transmission (s) on the mTRP k and/or the code point of tci-StateId s4 for UL transmission (s) on the mTRP l.

As indicated above, Fig. 6 is provided as an example. Other examples may differ from what is described with regard to Fig. 6.

Fig. 7 is a diagram illustrating an example 700 of indicating an SRS for uplink communications, in accordance with the present disclosure. Example 700 shows a macro network entity, or single TRP for both DL and UL transmissions TRP 705 (e.g., network node 110a) , that may communicate with UE 720 (e.g., UE 120) , multiple TRPs for UL only transmissions mTRP k 710 (e.g., network node 110b) , and mTRP l 715 (e.g., network node 110c) via a wireless network (e.g., wireless communication network 100) .

As shown by reference number 725, the sTRP 705 may transmit an indication of UL-only mTRPs (e.g., mTRP k, mTRP l) that support uplink communications from the UE 720. As shown by reference number 730, the UE 720 may transmit UE capability information and/or UE assistance information. The UE capability information may include UE capability information for supporting UL-only mTRPs. The UE capability information or UE assistance information may indicate a quantity of panels, a quantity of UL beams per panel, and/or a total quantity of UL beams.

As shown by reference number 735, the sTRP 705 may indicate a configuration (e.g., RRC configuration) for an SRS burst configuration. The SRS burst configuration may indicate one or more SRS set configurations where each SRS set configuration contains an SRS set ID or index a duration of an SRS burst, SRS resources (e.g., slot and/or symbol in time, PRBs in frequency, or port (s) ) of an SRS burst, the periodicity for periodic SRS burst, a time window or time interval between SRS bursts for multiple SRS bursts, a quantity of SRS bursts within the time window or for repeated SRS bursts, or condition (s) for triggering one or more SRS bursts. As shown by reference number 740, the UE 720 may transmit one or more SRS bursts as part of SRS beam sweep, based at least in part on one of the SRS burst configurations received from the sTRP by reference number 735, or based at least in part on an SRS burst indication from the sTRP (as shown by reference number 737) such as a MAC activating one or more SRS bursts or a DCI requesting one or more SRS bursts (e.g., the MAC-CE or DCI may indicate the SRS set index or ID for the SRS burst (s) and the time window or interval for the SRS bursts or the number of SRS bursts) . The beam sweep may be for mTRP selection and/or UL beam selection. The mTRPs may each measure the one or more SRSs received from the SRS burst (s) and report the measurement (s) and associated SRS (s) (e.g., RSSI, RSRP, or RSRQ measurements associated with the received SRSs or associated with the selected SRSs with the measurement above a threshold or associated with the selected SRS with the greatest RSSI, RSRP or RSRQ measurement) or greatest signal strength or quality SRS) to the sTRP 705. Alternatively, the mTRPs may each receive one or more of the SRSs and select an SRS to report (e.g., best SRS or greatest signal strength or quality SRS) to the sTRP 705. As shown by reference number 745, mTRP k may report the measurement (s) , SRS (s) , etc. (e.g., at least a measurement and/or an SRS such as SRS k) . As shown by reference number 750, mTRP l may report the measurement (s) , SRS(s) , etc. (e.g., at least a measurement and/or an SRS such as SRS l) .

The sTRP 705 may select one or more UL-only mTRPs based at least in part on received reports with measurement (s) and/or SRS (s) from mTRPs and select one or more SRSs respectively for the one or more selected mTRPs. The sTRP 705 may transmit an indication of a selected SRS or associated TCI state such that the UE 720 may determine a beam direction and/or resources to transmit UL communications (e.g., non-burst SRS, PUCCH, PUSCH, and/or PRACH) toward an mTRP. Reference numbers 755 to 795 provide multiple examples of such an indication. As shown by reference number 755, the sTRP 705 may transmit the indication in an RRC configuration, which contains configurations for UL transmissions based at least in part on the association with one or more SRSs selected from an SRS set (e.g., non-burst SRS configuration, PUCCH configuration, PUSCH configuration and/or PRACH configuration based on one or more SRS indices, IDs, SRS resource indices, or IDs of an SRS set used for the SRS burst (s) ) . As shown by reference number 760, the sTRP 705 may transmit the indication via a MAC activation of one or more spatial relationships (e.g., associated with one or more SRSs of an SRS set used for the SRS burst (s) ) or one or more TCI states associated with one or more selected SRSs (e.g., associated with one or more selected SRSs of an SRS set used for the SRS burst (s) ) .

In some aspects, the sTRP 705 may transmit DCI associated with a unified TCI state framework. As shown by reference number 765, the sTRP 705 may transmit the indication in DCI for a TCI state for UL to mTRP k or mTRP l. For example, the DCI may include a first TCI state for DL transmission from sTRP 705 (e.g., a PDSCH transmission as shown with the reference number 767) and/or a second TCI state for UL to the mTRP k 710 or mTRP l 715. As shown by reference number 770, the UE 720 may transmit a non-burst SRS, PUCCH message (e.g., ACK or NACK to the PDSCH as shown with the refence number 767) , a PUSCH message (e.g., with or without ACK or NACK to the PDSCH as shown with the refence number 767) or a PRACH message to mTRP k or mTRP l, depending on which mTRP is associated with the SRS or TCI state of the indication. As shown by reference number 775, the sTRP 705 may transmit the indication in DCI for a TCI state for UL to mTRP k or mTRP l. For example, the DCI may contain a first TCI state for UL on the sTRP 705 and/or a second TCI state for UL to the mTRP k 710 or mTRP l 715. As shown by reference number 780, the UE 720 may transmit an SRS, a PUCCH message, a PUSCH message or a PRACH message to the sTRP 705. As shown by reference number 785, the UE 720 may transmit a non-burst SRS, a PUCCH message, a PUSCH message or a PRACH message to mTRP k or mTRP l, depending on which mTRP is associated with the SRS or TCI state of the indication.

As shown by reference number 790, the sTRP 705 may transmit the indication in DCI for a TCI state for UL on mTRP k or mTRP l. For example, the DCI may include a first TCI state for UL to mTRP k and/or a second TCI state for UL to mTRP l. As shown by reference number 795, the UE 720 may transmit an SRS, a PUCCH message, or a PUSCH message to mTRP k or mTRP l, depending on which mTRP is associated with the SRS of the indication. In some aspects, the DCIs may be associated with a unified TCI state framework.

As indicated above, Fig. 7 is provided as an example. Other examples may differ from what is described with regard to Fig. 7.

Fig. 8 is a diagram illustrating an example process 800 performed, for example, at a UE or an apparatus of a UE, in accordance with the present disclosure. Example process 800 is an example where the apparatus or the UE (e.g., UE 120, UE 720) performs operations associated with uplink communication direction based on an SRS.

As shown in Fig. 8, in some aspects, process 800 may include transmitting an SRS set in a beam sweep (block 810) . For example, the UE (e.g., using transmission component 1104 and/or communication manager 1106, depicted in Fig. 11) may transmit an SRS set in a beam sweep, as described above.

As further shown in Fig. 8, in some aspects, process 800 may include receiving an indication to transmit an uplink communication toward a TRP (block 820) . For example, the UE (e.g., using reception component 1102 and/or communication manager 1106, depicted in Fig. 11) may receive an indication to transmit an uplink communication toward a TRP, as described above.

As further shown in Fig. 8, in some aspects, process 800 may include transmitting the uplink communication toward the TRP based at least in part on the indication (block 830) . For example, the UE (e.g., using transmission component 1104 and/or communication manager 1106, depicted in Fig. 11) may transmit the uplink communication toward the TRP based at least in part on the indication, as described above. The TRP may be an mTRP.

Process 800 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.

In a first aspect, the TRP is an uplink-only TRP.

In a second aspect, alone or in combination with the first aspect, the indication includes a spatial relation IE in an RRC configuration for a control channel, and the spatial relation IE includes a beam direction associated with an SRS.

In a third aspect, alone or in combination with one or more of the first and second aspects, the indication includes a TRP indication in DCI for a control channel transmission or a data transmission.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the indication includes an SRS indication in an RRC configuration for a data channel, and the SRS indication indicates a beam direction.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the indication includes an SRS resource indicator in DCI for a data channel transmission.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, process 800 includes receiving an indication of an offset for the uplink communication, where transmitting the uplink communication includes transmitting the uplink communication based at least in part on the offset.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, process 800 includes receiving an indication of a path loss adjustment, where transmitting the uplink communication includes transmitting the uplink communication based at least in part on the path loss adjustment.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the indication includes TRP information in a PRACH configuration, and the TRP is associated with an SRS of the SRS set in the beam sweep.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the indication includes SRS resource information in a PRACH configuration, and the SRS resource information includes one or more of an SRS resource or a beam direction of the PRACH associated with the SRS resource information.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the indication includes an mTRP indication in DCI for a PRACH. The mTRP indication may be a micro TRP indication.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, the indication includes SRS information in DCI for a PRACH.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, the indication includes at least one TCI state information that is associated with at least one SRS of the SRS set in the beam sweep.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, the at least one TCI state information indicates a unified TCI state for transmission to a TRP.

In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, process 800 includes transmitting an indication of a UE capability for supporting SRS beam sweeping, and receiving an SRS set configuration that indicates parameters for performing the beam sweep.

Although Fig. 8 shows example blocks of process 800, in some aspects, process 800 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 8. Additionally, or alternatively, two or more of the blocks of process 800 may be performed in parallel.

Fig. 9 is a diagram illustrating an example process 900 performed, for example, at a network entity or an apparatus of a network entity, in accordance with the present disclosure. Example process 900 is an example where the apparatus or the network entity (e.g., network node 110, sTRP 705) performs operations associated with uplink communication direction based on an SRS.

As shown in Fig. 9, in some aspects, process 900 may include receiving, from a TRP, an indication of a selected SRS (block 910) . For example, the network entity (e.g., using reception component 1202 and/or communication manager 1206, depicted in Fig. 12) may receive, from a TRP, an indication of a selected SRS, as described above.

As further shown in Fig. 9, in some aspects, process 900 may include transmitting, to a UE based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP (block 920) . For example, the network entity (e.g., using transmission component 1204 and/or communication manager 1206, depicted in Fig. 12) may transmit, to a UE based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP, as described above.

Process 900 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.

In a first aspect, the indication includes a spatial relation IE in an RRC configuration for a control channel, and the spatial relation IE includes a beam direction associated with an SRS.

In a second aspect, alone or in combination with the first aspect, the indication includes a TRP indication in DCI for a control channel transmission or a data transmission.

In a third aspect, alone or in combination with one or more of the first and second aspects, the indication includes an SRS indication in an RRC configuration for a data channel, and the SRS indicates a beam direction.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the indication includes an SRS resource indicator in DCI for a data channel transmission.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, process 900 includes transmitting an indication of a transmit power offset for the uplink communication.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, process 900 includes transmitting an indication of a path loss adjustment for the uplink communication.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the indication includes TRP information in a PRACH configuration, and the TRP is associated with an SRS indicated by the TRP information.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the indication includes SRS resource information in a PRACH configuration, and the SRS resource information includes at least one of the resources and the beam direction of the PRACH associated with the SRS resource information.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the indication includes a TRP indication in DCI for a PRACH.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the indication includes SRS information in DCI for a PRACH.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, the indication includes at least one TCI state information that is associated with an SRS indicated by the TRP.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, the TCI state information indicates a unified TCI state for transmission to a TRP.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, process 900 includes receiving an indication of a UE capability for supporting SRS beam sweeping, and transmitting an SRS set configuration that indicates parameters for performing a beam sweep with an SRS set.

Although Fig. 9 shows example blocks of process 900, in some aspects, process 900 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 9. Additionally, or alternatively, two or more of the blocks of process 900 may be performed in parallel.

Fig. 10 is a diagram illustrating an example process 1000 performed, for example, at a network entity or an apparatus of a network entity, in accordance with the present disclosure. Example process 1000 is an example where the apparatus or the network entity (e.g., network node 110, mTRP k 710, mTRP l 715) performs operations associated with uplink communication direction based on an SRS.

As shown in Fig. 10, in some aspects, process 1000 may include receiving one or more SRSs from a UE (block 1010) . For example, the network entity (e.g., using reception component 1202 and/or communication manager 1206, depicted in Fig. 12) may receive one or more SRSs from a UE, as described above.

As further shown in Fig. 10, in some aspects, process 1000 may include transmitting, in an uplink message, an indication of an SRS that is selected based at least in part on a signal strength or quality (block 1020) . For example, the network entity (e.g., using transmission component 1204 and/or communication manager 1206, depicted in Fig. 12) may transmit, in an uplink message, an indication of an SRS that is selected based at least in part on a signal strength or quality, as described above.

Process 1000 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.

Although Fig. 10 shows example blocks of process 1000, in some aspects, process 1000 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 10. Additionally, or alternatively, two or more of the blocks of process 1000 may be performed in parallel.

Fig. 11 is a diagram of an example apparatus 1100 for wireless communication, in accordance with the present disclosure. The apparatus 1100 may be a UE, or a UE may include the apparatus 1100. In some aspects, the apparatus 1100 includes a reception component 1102, a transmission component 1104, and/or a communication manager 1106, which may be in communication with one another (for example, via one or more buses and/or one or more other components) . In some aspects, the communication manager 1106 is the communication manager 140 described in connection with Fig. 1. As shown, the apparatus 1100 may communicate with another apparatus 1108, such as a UE or a network node (such as a CU, a DU, an RU, or a base station) , using the reception component 1102 and the transmission component 1104.

In some aspects, the apparatus 1100 may be configured to perform one or more operations described herein in connection with Figs. 1-7. Additionally, or alternatively, the apparatus 1100 may be configured to perform one or more processes described herein, such as process 800 of Fig. 8. In some aspects, the apparatus 1100 and/or one or more components shown in Fig. 11 may include one or more components of the UE described in connection with Fig. 2. Additionally, or alternatively, one or more components shown in Fig. 11 may be implemented within one or more components described in connection with Fig. 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 1102 may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus 1108. The reception component 1102 may provide received communications to one or more other components of the apparatus 1100. In some aspects, the reception component 1102 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 of the apparatus 1100. In some aspects, the reception component 1102 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, one or more memories, or a combination thereof, of the UE described in connection with Fig. 2.

The transmission component 1104 may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus 1108. In some aspects, one or more other components of the apparatus 1100 may generate communications and may provide the generated communications to the transmission component 1104 for transmission to the apparatus 1108. In some aspects, the transmission component 1104 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 1108. In some aspects, the transmission component 1104 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, one or more memories, or a combination thereof, of the UE described in connection with Fig. 2. In some aspects, the transmission component 1104 may be co-located with the reception component 1102 in one or more transceivers.

The communication manager 1106 may support operations of the reception component 1102 and/or the transmission component 1104. For example, the communication manager 1106 may receive information associated with configuring reception of communications by the reception component 1102 and/or transmission of communications by the transmission component 1104. Additionally, or alternatively, the communication manager 1106 may generate and/or provide control information to the reception component 1102 and/or the transmission component 1104 to control reception and/or transmission of communications.

The transmission component 1104 may transmit an SRS set in a beam sweep. The reception component 1102 may receive an indication to transmit an uplink communication toward a TRP. The transmission component 1104 may transmit the uplink communication toward the TRP based at least in part on the indication.

The reception component 1102 may receive an indication of an offset for the uplink communication, wherein transmitting the uplink communication includes transmitting the uplink communication based at least in part on the offset. The reception component 1102 may receive an indication of a path loss adjustment, wherein transmitting the uplink communication includes transmitting the uplink communication based at least in part on the path loss adjustment.

The transmission component 1104 may transmit an indication of a UE capability for supporting SRS beam sweeping. The reception component 1102 may receive an SRS set configuration that indicates parameters for performing the beam sweep.

The number and arrangement of components shown in Fig. 11 are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in Fig. 11. Furthermore, two or more components shown in Fig. 11 may be implemented within a single component, or a single component shown in Fig. 11 may be implemented as multiple, distributed components. Additionally, or alternatively, a set of (one or more) components shown in Fig. 11 may perform one or more functions described as being performed by another set of components shown in Fig. 11.

Fig. 12 is a diagram of an example apparatus 1200 for wireless communication, in accordance with the present disclosure. The apparatus 1200 may be a network entity, or a network entity may include the apparatus 1200. In some aspects, the apparatus 1200 includes a reception component 1202, a transmission component 1204, and/or a communication manager 1206, which may be in communication with one another (for example, via one or more buses and/or one or more other components) . In some aspects, the communication manager 1206 is the communication manager 150 or 160 described in connection with Fig. 1. As shown, the apparatus 1200 may communicate with another apparatus 1208, such as a UE or a network node (such as a CU, a DU, an RU, or a base station) , using the reception component 1202 and the transmission component 1204.

In some aspects, the apparatus 1200 may be configured to perform one or more operations described herein in connection with Figs. 1-7. Additionally, or alternatively, the apparatus 1200 may be configured to perform one or more processes described herein, such as process 900 of Fig. 9, process 1000 of Fig. 10, or a combination thereof. In some aspects, the apparatus 1200 and/or one or more components shown in Fig. 12 may include one or more components of the network entity described in connection with Fig. 2. Additionally, or alternatively, one or more components shown in Fig. 12 may be implemented within one or more components described in connection with Fig. 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 1202 may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus 1208. The reception component 1202 may provide received communications to one or more other components of the apparatus 1200. In some aspects, the reception component 1202 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 of the apparatus 1200. In some aspects, the reception component 1202 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, one or more memories, or a combination thereof, of the network entity described in connection with Fig. 2.

The transmission component 1204 may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus 1208. In some aspects, one or more other components of the apparatus 1200 may generate communications and may provide the generated communications to the transmission component 1204 for transmission to the apparatus 1208. In some aspects, the transmission component 1204 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 1208. In some aspects, the transmission component 1204 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, one or more memories, or a combination thereof, of the network entity described in connection with Fig. 2. In some aspects, the transmission component 1204 may be co-located with the reception component 1202 in one or more transceivers.

The communication manager 1206 may support operations of the reception component 1202 and/or the transmission component 1204. For example, the communication manager 1206 may receive information associated with configuring reception of communications by the reception component 1202 and/or transmission of communications by the transmission component 1204. Additionally, or alternatively, the communication manager 1206 may generate and/or provide control information to the reception component 1202 and/or the transmission component 1204 to control reception and/or transmission of communications.

In some aspects, the reception component 1202 may receive, from a TRP, an indication of a selected SRS. The transmission component 1204 may transmit, to a UE based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP.

The transmission component 1204 may transmit an indication of a transmit power offset for the uplink communication. The transmission component 1204 may transmit an indication of a path loss adjustment for the uplink communication. The reception component 1202 may receive an indication of a UE capability for supporting SRS beam sweeping.

The transmission component 1204 may transmit an SRS set configuration that indicates parameters for performing a beam sweep with an SRS set.

In some aspects, the reception component 1202 may receive one or more SRSs from a UE. The transmission component 1204 may transmit, in an uplink message, an indication of an SRS that is selected based at least in part on a signal strength or quality.

The number and arrangement of components shown in Fig. 12 are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in Fig. 12. Furthermore, two or more components shown in Fig. 12 may be implemented within a single component, or a single component shown in Fig. 12 may be implemented as multiple, distributed components. Additionally, or alternatively, a set of (one or more) components shown in Fig. 12 may perform one or more functions described as being performed by another set of components shown in Fig. 12.

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

Aspect 1: A method of wireless communication performed by a user equipment (UE) , comprising: transmitting a sounding reference signal (SRS) set in a beam sweep; receiving an indication to transmit an uplink communication toward a transmit receive point (TRP) ; and transmitting the uplink communication toward the TRP based at least in part on the indication.

Aspect 2: The method of Aspect 1, wherein the TRP is an uplink-only TRP.

Aspect 3: The method of any of Aspects 1-2, wherein the indication includes a spatial relation information element (IE) in a radio resource control configuration for a control channel, and wherein the spatial relation IE includes a beam direction associated with an SRS.

Aspect 4: The method of any of Aspects 1-3, wherein the indication includes a TRP indication in downlink control information for a control channel transmission or a data transmission.

Aspect 5: The method of any of Aspects 1-4, wherein the indication includes an SRS indication in a radio resource control configuration for a data channel, and wherein the SRS indication indicates a beam direction.

Aspect 6: The method of any of Aspects 1-5, wherein the indication includes an SRS resource indicator in downlink control information for a data channel transmission.

Aspect 7: The method of any of Aspects 1-6, further comprising receiving an indication of an offset for the uplink communication, wherein transmitting the uplink communication includes transmitting the uplink communication based at least in part on the offset.

Aspect 8: The method of any of Aspects 1-7, further comprising receiving an indication of a path loss adjustment, wherein transmitting the uplink communication includes transmitting the uplink communication based at least in part on the path loss adjustment.

Aspect 9: The method of any of Aspects 1-8, wherein the indication includes TRP information in a physical random access channel configuration, and wherein the TRP is associated with an SRS of the SRS set in the beam sweep.

Aspect 10: The method of any of Aspects 1-9, wherein the indication includes SRS resource information in a physical random access channel (PRACH) configuration, and wherein the SRS resource information includes one or more of an SRS resource or a beam direction of the PRACH associated with the SRS resource information.

Aspect 11: The method of any of Aspects 1-10, wherein the indication includes a multiple transmit receive point (mTRP) indication in downlink control information for a physical random access channel.

Aspect 12: The method of any of Aspects 1-11, wherein the indication includes SRS information in downlink control information for a physical random access channel.

Aspect 13: The method of any of Aspects 1-12, wherein the indication includes at least one transmission configuration indicator (TCI) state information that is associated with at least one SRS of the SRS set in the beam sweep.

Aspect 14: The method of Aspect 13, wherein the at least one TCI state information indicates a unified TCI state for transmission to a TRP.

Aspect 15: The method of any of Aspects 1-14, further comprising: transmitting an indication of a UE capability for supporting SRS beam sweeping; and receiving an SRS set configuration that indicates parameters for performing the beam sweep.

Aspect 16: A method of wireless communication performed by a network entity, comprising: receiving, from a transmit receive point (TRP) , an indication of a selected sounding reference signal (SRS) ; and transmitting, to a user equipment (UE) based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP.

Aspect 17: The method of Aspect 16, wherein the indication includes a spatial relation information element (IE) in a radio resource control configuration for a control channel, and wherein the spatial relation IE includes a beam direction associated with an SRS.

Aspect 18: The method of any of Aspects 16-17, wherein the indication includes a TRP indication in downlink control information for a control channel transmission or a data transmission.

Aspect 19: The method of any of Aspects 16-18, wherein the indication includes an SRS indication in a radio resource control configuration for a data channel, and wherein the SRS indicates a beam direction.

Aspect 20: The method of any of Aspects 16-19, wherein the indication includes an SRS resource indicator in downlink control information for a data channel transmission.

Aspect 21: The method of any of Aspects 16-20, further comprising transmitting an indication of a transmit power offset for the uplink communication.

Aspect 22: The method of any of Aspects 16-21, further comprising transmitting an indication of a path loss adjustment for the uplink communication.

Aspect 23: The method of any of Aspects 16-22, wherein the indication includes TRP information in a physical random access channel configuration, and wherein the TRP is associated with an SRS indicated by the TRP information.

Aspect 24: The method of any of Aspects 16-23, wherein the indication includes SRS resource information in a physical random access channel (PRACH) configuration, and wherein the SRS resource information includes at least one of the resources and the beam direction of the PRACH associated with the SRS resource information.

Aspect 25: The method of any of Aspects 16-24, wherein the indication includes a TRP indication in downlink control information for a physical random access channel.

Aspect 26: The method of any of Aspects 16-25, wherein the indication includes SRS information in downlink control information for a physical random access channel.

Aspect 27: The method of any of Aspects 16-26, wherein the indication includes at least one transmission configuration indicator (TCI) state information that is associated with an SRS indicated by the TRP.

Aspect 28: The method of Aspect 27, wherein the TCI state information indicates a unified TCI state for transmission to a TRP.

Aspect 29: The method of any of Aspects 16-28, further comprising: receiving an indication of a UE capability for supporting SRS beam sweeping; and transmitting an SRS set configuration that indicates parameters for performing a beam sweep with an SRS set.

Aspect 30: A method of wireless communication performed by a network entity, comprising: receiving one or more sounding reference signals (SRSs) from a user equipment (UE) ; and transmitting, in an uplink message, an indication of an SRS that is selected based at least in part on a signal strength or quality.

Aspect 31: 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 1-30.

Aspect 32: 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 1-30.

Aspect 33: An apparatus for wireless communication, the apparatus comprising at least one means for performing the method of one or more of Aspects 1-30.

Aspect 34: 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 1-30.

Aspect 35: 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 1-30.

Aspect 36: 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 1-30.

Aspect 37: 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 1-30.

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) .

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

An apparatus for wireless communication at a user equipment (UE) , comprising:

one or more memories; and

one or more processors, coupled to the one or more memories, individually or collectively configured to cause the UE to:

transmit a sounding reference signal (SRS) set in a beam sweep;

receive an indication to transmit an uplink communication toward a transmit receive point (TRP) ; and

transmit the uplink communication toward the TRP based at least in part on the indication.
The apparatus of claim 1, wherein the TRP is an uplink-only TRP.
The apparatus of claim 1, wherein the indication includes a spatial relation information element (IE) in a radio resource control configuration for a control channel, and wherein the spatial relation IE includes a beam direction associated with an SRS.
The apparatus of claim 1, wherein the indication includes a TRP indication in downlink control information for a control channel transmission or a data transmission.
The apparatus of claim 1, wherein the indication includes an SRS indication in a radio resource control configuration for a data channel, and wherein the SRS indication indicates a beam direction.
The apparatus of claim 1, wherein the indication includes an SRS resource indicator in downlink control information for a data channel transmission.
The apparatus of claim 1, wherein the one or more processors are individually or collectively futher configured to cause the UE to receive an indication of an offset for the uplink communication, and wherein to transmit the uplink communication, the one or more processors are individually or collectively configured to cause the UE to transmit the uplink communication based at least in part on the offset.
The apparatus of claim 1, wherein the one or more processors are individually or collectively further configured to cause the UE to receive an indication of a path loss adjustment, and wherein to transmit the uplink communication, the one or more processors are individually or collectively configured to cause the UE to transmit the uplink communication based at least in part on the path loss adjustment.
The apparatus of claim 1, wherein the indication includes TRP information in a physical random access channel configuration, and wherein the TRP is associated with an SRS of the SRS set in the beam sweep.
The apparatus of claim 1, wherein the indication includes SRS resource information in a physical random access channel (PRACH) configuration, and wherein the SRS resource information includes one or more of an SRS resource or a beam direction of the PRACH associated with the SRS resource information.
The apparatus of claim 1, wherein the indication includes a multiple transmit receive point (mTRP) indication in downlink control information for a physical random access channel.
The apparatus of claim 1, wherein the indication includes SRS information in downlink control information for a physical random access channel.
The apparatus of claim 1, wherein the indication includes at least one transmission configuration indicator (TCI) state information that is associated with at least one SRS of the SRS set in the beam sweep.
The apparatus of claim 13, wherein the at least one TCI state information indicates a unified TCI state for transmission to a TRP.
The apparatus of claim 1, wherein the one or more processors are individually or collectively further configured to cause the UE to:

transmit an indication of a UE capability for supporting SRS beam sweeping; and

receive an SRS set configuration that indicates parameters for performing the beam sweep.
An apparatus for wireless communication at a network entity, comprising:

one or more memories; and

one or more processors, coupled to the one or more memories, individually or collectively configured to cause the network entity to:

receive, from a transmit receive point (TRP) , an indication of a selected sounding reference signal (SRS) ; and

transmit, to a user equipment (UE) based at least in part on the selected SRS, an indication for transmitting an uplink communication to a selected TRP.
The apparatus of claim 16, wherein the indication includes a spatial relation information element (IE) in a radio resource control configuration for a control channel or a data channel, and wherein the spatial relation IE includes a beam direction associated with an SRS.
The apparatus of claim 16, wherein the indication includes a TRP indication, an SRS indication, or an SRS resource indicator in downlink control information for a control channel transmission or a data transmission.
The apparatus of claim 16, wherein the indication includes an SRS indication in a radio resource control configuration for a data channel, and wherein the SRS indicates a beam direction.
An apparatus for wireless communication at a network entity, comprising:

one or more memories; and

one or more processors, coupled to the one or more memories, individually or collectively configured to cause the network entity to:

receive one or more sounding reference signals (SRSs) from a user equipment (UE) ; and

transmit an indication of an SRS that is selected based at least in part on a signal strength or quality.