WO2025196709A1 - Channel state information feedback for reciprocity based coherent joint transmission - Google Patents

Abstract

Systems and methods are disclosed for Channel State Information (CSI) feedback for reciprocity based coherent joint transmission. In one embodiment, a method performed by a User Equipment (UE) comprises receiving, from a network node, configuration information for phase offsets feedback, where the configuration comprises a plurality of CSI Reference Signal (CSI-RS) resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources. The method further comprises computing phase offsets based on the plurality of CSI-RS resources received on the indicated antenna port of the UE and reporting, to the network node, the computed phase offsets. In this manner, proper feedback of phase offsets for reciprocity based coherent joint transmission is enabled.

Description

CHANNEL STATE INFORMATION FEEDBACK FOR RECIPROCITY BASED COHERENT JOINT TRANSMISSION RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Patent Application No. 63/567,665, filed March 20, 2024, the disclosure of which is hereby incorporated herein by reference in its entirety. TECHNICAL FIELD [0002] The present disclosure relates generally to Channel State Information (CSI) feedback. BACKGROUND [0003] Similar to 3^rd Generation Partnership Project (3GPP) Long Term Evolution (LTE), the 5^th Generation (5G) mobile systems or New Radio (NR) uses Orthogonal Frequency Division Multiplexing (OFDM) in the downlink from a network node, gNodeB (gNB), evolved NodeB (eNB), or base station, to a User Equipment (UE). In the uplink from UE to gNB, both OFDM and Discrete Fourier Transform (DFT)-Spread OFDM (DFT-S-OFDM) are supported. The basic NR physical resource can thus be seen as a time-frequency grid as illustrated in Figure 1, where a Resource Block (RB) in a 14-symbol slot is shown. An RB corresponds to twelve (12) contiguous subcarriers in the frequency domain. RBs are numbered in the frequency domain, starting with 0 from one end of the system bandwidth. Each resource element corresponds to one OFDM subcarrier during one OFDM symbol interval. [0004] Different subcarrier spacings are supported in NR. The supported subcarrier spacings _{(also referred to as numerologies) are given by ∆^^^^ = (15 × 2^^^^) kilohertz (kHz) where ^^^^ is a non-negative integer and can be one of {0, 1, 2, 3, 4}. ∆^^^^ = 15^^^^^^^^^^^^ (e.g., ^^^^ = 0) is the basic (or} reference) subcarrier spacing that is also used in LTE. ^^^^ is also referred to as the numerology. [0005] In the time domain, downlink and uplink transmissions in NR are organized into equally sized subframes of 1 millisecond (ms) each. A subframe is further divided into multiple slots of equal duration. The slot length is dependent on the subcarrier spacing or numerology and is given by ¹ ms. Each slot consists of fourteen (14) OFDM symbols for normal Cyclic Prefix (CP). [0006] Data scheduling in NR can be in slot basis. Downlink (DL) transmissions can be dynamically scheduled, i.e., in each slot the gNB transmits Downlink Control Information (DCI) about which UE data is to be transmitted to and which resource blocks in the current downlink slot the data is transmitted on. The control information is carried on Physical Downlink Control Channel (PDCCH), and data is carried on Physical Downlink Shared Channel (PDSCH). A UE first detects and decodes PDCCH and, if a PDCCH is decoded successfully, the UE then decodes the corresponding PDSCH based on the decoded control information in the PDCCH. [0007] Uplink (UL) data transmission can also be dynamically scheduled using PDCCH. Similar to downlink, a UE first decodes uplink grants in PDCCH and then transmits data over the Physical Uplink Shared Channel (PUSCH) based the decoded control information in the uplink grant such as modulation order, coding rate, uplink resource allocation, and etc. [0008] In 3GPP NR Release 18, Channel State Information (CSI) feedback or reporting for Coherent Joint PDSCH Transmission (CJT) over multiple Transmission and Reception Points (TRPs) was introduced. In CJT, the signal of each Multiple Input Multiple Output (MIMO) layer of a PDSCH is transmitted jointly from multiple TRPs to a UE in a same time and frequency resource. Before the transmission, the signal at each TRP is phase adjusted such that the phase adjusted signals from the multiple TRPs are phase aligned when reaching the UE and, thus, are coherently combined. The power of the combined signal should be larger than that when received from a single TRP. This improves the signal quality received at the UE. [0009] Figure 2 illustrates an example of coherent joint PDSCH transmission over two TRPs. _{In the example shown in Figure 2, a PDSCH with ^^^^ layers, i.e., ^^^^ = [^^^^1, ^^^^2, … , ^^^^^^^^]^^^^, is} transmitted from two TRPs after being precoded by a precoding matrix at TRP#1 and a precoding matrix ^^^^₂ at TRP#2. Each element of the precoding matrices is a complex coefficient. The precoding helps to achieve coherent (or constructive) combining of signals from the two TRPs at the UE for each layer. [0010] The precoders ^^^^₁ and ^^^^₂ can be reported by the UE as part of a CSI report for CJT, which was introduced in 3GPP Release 18, or determined by the network based on UL reference signals transmitted from the UE in Time Division Duplex (TDD) systems assuming channel reciprocity. The latter is referred to as reciprocity based CJT. An CJT CSI typically comprises a Rank (i.e., number of layers) Indicator (RI), a Channel Quality Indicator (CQI), and a Precoding Matrix Indicator (PMI). The precoders ^^^^₁ and ^^^^₂ are indicated by the PMI. [0011] In NR Release 18 CJT CSI, ideal synchronization between TRPs is assumed. In other words, the symbol/slot/frame timing and carrier frequency are exactly the same in different TRPs. However, in practice, some level of timing and carrier frequency offsets do exist across different TRPs. The issue has been recognized and will be addressed in NR Release 19 via UE measurement and reporting of time and frequency differences between TRPs. The reporting will be a standalone report, meaning that it will not be combined with legacy CSI reports. [0012] In NR, for CSI reporting purpose, a UE can be configured with one or more channel (CSI) report configurations each comprising one or more Non-zero Power (NZP) CSI Reference Signal (CSI-RS) resources for channel measurements and a codebook used for CSI feedback. In addition to PMI and RI, the feedback typically also comprises one (for rank<=4) or two (for rank>4) CQIs. [0013] PMI and CQI feedback can be either wideband or per subband, where a wideband can be a whole Bandwidth Part (BWP) configured while a subband is defined as a number of contiguous Physical Resource Blocks (PRBs) within a BWP. [0014] A CSI report configuration is performed by Radio Resource Control (RRC) signaling via a RRC parameter CSI-ReportConfig defined in 3GPP Technical Specification (TS) 38.331 (see, e.g., V18.0.0). The report can be periodic or semi-persistent on PUCCH (physical uplink control channel) in a cell in which the CSI-ReportConfig is configured, or semi-persistent or aperiodic sent on Physical Uplink Shared Channel (PUSCH) triggered by a DCI format received in the cell in which the CSI-ReportConfig is configured. [0015] A NZP CSI-RS resource can have up to thirty-two (32) CSI-RS antenna ports. In NR CSI reporting, one or more NZP CSI-RS resource sets can be configured and associated to a CSI report configuration for channel measurements. A NZP CSI-RS resource set contains one or more NZP CSI-RS resources. [0016] CSI-RS is used for downlink channel measurement between a transmit antenna and a receive antenna. CSI-RS is configured by CSI-RS resources and can be transmitted on one or multiple antenna ports, also referred to as CSI-RS antenna ports or CSI-RS ports. Each CSI-RS port is transmitted in certain time and frequency resources configured in a corresponding CSI-RS resource. The supported number of antenna ports in NR are {1, 2, 4, 8, 12, 16, 24, 32}. By measuring the received CSI-RS, a UE can estimate the channel that the CSI-RS is traversing, including the radio propagation channel and antenna gains. The CSI-RS for the above purpose is also referred to as NZP CSI-RS. [0017] Figure 3 illustrates an example of a Resource Element (RE) allocation for a 12-port CSI-RS resource in NR. Figure 3 shows an example of one CSI-RS RE allocation for 12 CSI- RS ports in a CSI-RS resource with frequency density one, i.e., average one RE per RB per CSI- RS port. CSI-RS is transmitted in every RB in a configured CSI-RS bandwidth. Only CSI-RS in one RB is shown Figure 3. [0018] In 6^th Generation (6G), terms other than NZP CSI-RS might be used. For example, a new downlink reference signal or downlink synchronization signal might be introduced in 6G which can be used instead of NZP CSI-RS. The 6G downlink reference signals and/or downlink synchronization signals might be aperiodically, semi-persistently or periodically transmitted. In the following the terms “DL-RS”, “NZP CSI-RS” and “NZP CSI-RS resource set” may be used interchangeably. Also, although the term TRP is used herein, the term TRP may not be captured in 3GPP specifications. Instead, a TRP can be represented by any one of ‘NZP CSI-RS resource set’, ‘NZP CSI-RS resource’, ‘TRS resource set’, and/or ‘TRS resource’, or in general downlink reference signal (DL-RS). SUMMARY [0019] Systems and methods are disclosed for Channel State Information (CSI) feedback for reciprocity based coherent joint transmission. In one embodiment, a method performed by a User Equipment (UE) comprises receiving, from a network node, configuration information for phase offsets feedback, where the configuration comprises a plurality of CSI Reference Signal (CSI-RS) resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources. The method further comprises computing phase offsets based on the plurality of CSI-RS resources received on the indicated antenna port of the UE and reporting, to the network node, the computed phase offsets. In this manner, proper feedback of phase offsets for reciprocity based coherent joint transmission is enabled. [0020] In one embodiment, the method further comprises receiving a configuration of one or more Sounding Reference Signal (SRS) resources, wherein each of the one or more SRS resources comprises one or more antenna ports. In one embodiment, the CSI-RS resources are associated to one of the one or more SRS resources. In one embodiment, the indication of an antenna port of the UE comprises information indicating an associated SRS resource out of the one or more SRS resources and information of an antenna port of the associated SRS resource. In one embodiment, the indicated antenna port of the UE is a same antenna port for transmitting an associated SRS resource from the UE to the network. In one embodiment, the one or more SRS resources are for antenna switching. [0021] In one embodiment, each of the plurality of CSI-RS resources is associated to one of a plurality of Transmission and Reception Points (TRPs). [0022] In one embodiment, computing the phase offsets based on the plurality of CSI-RS resources comprises computing a phase difference between each of the plurality of CSI-RS resources and a reference CSI-RS resource, wherein the reference CSI-RS resource is one of the plurality of CSI-RS resources. [0023] In one embodiment, reporting the computed phase offsets comprising reporting a computed phase offset for each of plurality of CSI-RS resources excluding the phase offset for a reference CSI-RS resource, wherein the phase offset for reference CSI-RS resource is zero. [0024] In one embodiment, the method further comprises receiving a configuration for timing offsets feedback based on the plurality of reference signal resources, and computing and reporting a time difference between each of the plurality of CSI-RS resources and a reference CSI-RS resource, wherein the reference CSI-RS resource is one of the plurality of CSI-RS resources and the timing offset for reference CSI-RS resource is zero and is not reported. [0025] In one embodiment, the CSI-RS resources are precoded based on channel information derived from the associated SRS resource at the network. [0026] In one embodiment, the method further comprises transmitting, at a first time instance, the associated SRS resource from the indicated antenna port of the UE. [0027] In one embodiment, the configuration information for phase offsets feedback further comprises information indicating phase offsets feedback per subband. [0028] In one embodiment, reporting the phase offsets comprises reporting the phase offsets computed per subband. [0029] In one embodiment, the configuration information received from the network node further comprises information that configures the UE to receive each of the plurality of CSI-RS resources at a second time instance, wherein the second time instance occurs later than a first time instance at which the UE transmits SRS. [0030] Corresponding embodiments of a UE are also disclosed. In one embodiment, a UE is adapted to receive, from a network node, configuration information for phase offsets feedback, where the configuration comprises a plurality of CSI-RS resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources. The UE is further adapted to compute phase offsets based on the plurality of CSI-RS resources received on the indicated antenna port of the UE and report, to the network node, the computed phase offsets. [0031] In one embodiment, a UE comprises a communication interface comprising a transmitter and a receiver. The UE further comprises processing circuitry associated with the communication interface, wherein the processing circuitry is configured to cause the UE to receive, from a network node, configuration information for phase offsets feedback, where the configuration comprises a plurality of CSI-RS resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources. The processing circuitry is further configured to cause the UE to compute phase offsets based on the plurality of CSI-RS resources received on the indicated antenna port of the UE and report, to the network node, the computed phase offsets. [0032] Embodiments of a method performed by a network node in a Radio Access Network (RAN) of a wireless communications system are also disclosed. In one embodiment, a method performed by a network node in a RAN of a wireless communications system comprises transmitting, to a UE, configuration information for phase offsets feedback, where the configuration comprises a plurality of CSI-RS resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources. The method further comprises transmitting, on the indicated one of the plurality of antenna ports of the UE, a single port CSI-RS from each of a plurality of Transmission and Reception Points (TRPs) associated to the network node and receiving, from the UE, a report of phase offsets for the plurality of TRPs. [0033] Corresponding embodiments of a network node are also disclosed. In one embodiment, a network node for a RAN of a wireless communications system is adapted to transmit, to a UE, configuration information for phase offsets feedback, where the configuration comprises a plurality of CSI-RS resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources. The network node is further adapted to transmit, on the indicated one of the plurality of antenna ports of the UE, a single port CSI-RS from each of a plurality of TRPs associated to the network node and receiving, from the UE, a report of phase offsets for the plurality of TRPs. [0034] In one embodiment, a network node for a RAN of a wireless communications system comprises processing circuitry configured to cause the network node to transmit, to a UE, configuration information for phase offsets feedback, where the configuration comprises a plurality of CSI-RS resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources. The processing circuitry is further configured to cause the network node to transmit, on the indicated one of the plurality of antenna ports of the UE, a single port CSI-RS from each of a plurality of TRPs associated to the network node and receiving, from the UE, a report of phase offsets for the plurality of TRPs. BRIEF DESCRIPTION OF THE DRAWINGS [0035] The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain the principles of the disclosure. [0036] Figure 1 illustrates New Radio (NR) physical resources; [0037] Figure 2 illustrates an example of coherent joint PDSCH transmission over two TRPs. [0038] Figure 3 illustrates an example of a RE allocation for a 12-port CSI-RS resource in NR. [0039] Figure 4 is a flow chart is a flow chart that illustrating a process performed by a User Equipment (UE) and gNodeB, in accordance with one embodiment of the present disclosure; [0040] Figure 5 illustrates an example of joint DL transmitting from multiple TRPs. [0041] Figure 6 illustrates an example of UL and DL Timing at the UE and the TRPs. [0042] Figure 7A is a flow chart is a flow chart that illustrating a process performed by a User Equipment (UE) and gNodeB, in accordance with one embodiment of the present disclosure; [0043] Figure 7B is a flow chart is a flow chart that illustrating a process performed by a User Equipment (UE) and gNodeB, in accordance with one embodiment of the present disclosure; [0044] Figure 7C illustrates a high-level block diagram of SRS transmission and reception, more particularly of UL transmission and reception, in accordance with one embodiment of the present disclosure; [0045] Figure 8 illustrates a flow chart that illustrating a process performed by a User Equipment (UE) and gNodeB, in accordance with one embodiment of the present disclosure; [0046] Figure 9 shows an example of a communication system in accordance with some embodiments of the present disclosure; [0047] Figure 10 shows a User Equipment device (UE) in accordance with some embodiments of the present disclosure; [0048] Figure 11 shows a network node in accordance with some embodiments of the present disclosure; [0049] Figure 12 is a block diagram of a host, which may be an embodiment of the host of Figure 9, in accordance with various aspects of the present disclosure described herein; [0050] Figure 13 is a block diagram illustrating a virtualization environment in which functions implemented by some embodiments of the present disclosure may be virtualized; and [0051] Figure 14 shows a communication diagram of a host communicating via a network node with a UE over a partially wireless connection in accordance with some embodiments of the present disclosure. DETAILED DESCRIPTION [0052] The embodiments set forth below represent information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure. In all embodiments, it will be understood that steps in which a user equipment and a gNodeB communicate information, if a step is specifically described for one of these nodes, the other node will perform the reciprocal step: form example, if a user equipment is reporting feedback to a gNodeB, it will be understood to be disclosed that the gNodeB receives the reported feedback. [0053] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art. [0054] There currently exist certain challenges. In reciprocity-based downlink (DL) transmission, the receive and transmit circuitries at each Transmission and Reception Point (TRP) is typically calibrated such that the same gain and phase are maintained across different receive and transmit circuitries associated to different antennas. The absolute phase at each TRP is unknown and is not needed for single TRP transmission. For Coherent Joint Transmission (CJT) (i.e., Coherent Joint Physical Downlink Shared Channel (PDSCH) Transmission) based on CJT Channel State Information (CSI) feedback, the unknown phase at each TRP is not a problem because it is considered in the reported Precoding Matrix Indicator (PMI). [0055] The unknown phase at each TRP is, however, a problem for reciprocity based CJT because coherent transmission is not possible without knowing the phase difference between the TRPs. One possible solution is to request the User Equipment (UE) to feedback the phase differences between TRPs. Such a method is described in patent application PCT/IB2024/050198 filed on March 1, 2024 which published on September 6, 2024 as WO2024/181911, in which ideal time and frequency synchronization between TRPs is assumed. [0056] In United States Patent Application 63/555307 and R1-2400753, CSI enhancements for large antenna arrays and CJT, Ericsson, 3GPP TSG RAN WG1 #116, Athens, Greece, Feb 26th – Mar 1st, 2024, methods are proposed on measurement and feedback of phase differences between TRPs by a UE when there are timing and/or carrier frequency differences between the TRPs. In one method, the effect of the timing and/or carrier frequency differences is first removed by the UE from DL channel measurement based on a CSI Reference Signal (CSI-RS) resource associated to each TRP, resulting in a time/frequency compensated DL channel measurement associated to each TRP. The phase difference between each TRP and a reference TRP is then estimated and reported based on the respective time/frequency compensated DL channel measurement. If the UE is equipped with multiple receive (Rx) antennas, the phase difference is computed based on DL measurement on all the Rx antennas at the UE. In United States Patent Application 63/555307 and R1-2400753, it is assumed that a precoder has been obtained at each TRP but there is an unknown phase difference between each TRP and a reference TRP. The unknown phases are obtained by the feedback from the UE to the gNode (gNB). The timing offsets between TRPs are estimated separately and the phase differences due to the timing offsets are known at the gNB. When there are multiple layers, the phase difference between each TRP and a reference TRP can be different for different layers. In this case, feeding back a single phase difference/offset for each TRP as described in United States Patent Application 63/555307 and R1-2400753, may not be enough. [0057] In R1-2401437, CSI enhancements for up to 128 ports and UE-assisted CJT with non-ideal TRP synchronization, Qualcomm Incorporated, 3GPP TSG RAN WG1 #116, Athens, Greece, Feb 26th – Mar 1st, 2024, another method is proposed to obtain the phase differences between TRPs, in which a CSI-RS with a single CSI-RS port is transmitted from each TRP. The CSI-RS is precoded, i.e., multiplied by the conjugate of a received uplink (UL) Sounding Reference Signal (SRS) signal at each subcarrier of the corresponding TRP. A UE measures DL channel based on the pre-compensated CSI-RS from each TRP, and estimates and feeds back both a timing offset and a phase difference associated to each TRP. In R1-2401437, an SRS transmitted from a single antenna port is assumed and the same antenna port is assumed to be used for receiving the precoded CSI-RS. When a UE is equipped with multiple receive antennas, to estimate the DL channel at each TRP, SRS needs to be transmitted over all the receive antennas, either simultaneously or one antenna at a time via antenna switching. In this case, how to measure and feedback phase and/or timing offsets is a problem. [0058] Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges. A method is proposed for feedback of phase offsets or both phase and timing offsets for a first TRP and a second TRP in a wireless network, wherein the first TRP is associated to a first CSI-RS resource and the second TRP is associated to a second CSI-RS resource, and wherein each of the first and the second TRPs comprise respectively a first and a second plurality of antenna ports, and wherein the UE comprises a third plurality of antenna ports. A flowchart of the method is illustrated in Figure 4. As illustrated in Figure 4, the method comprises one or more of the following: • Step 400: Receiving a configuration by the UE to transmit a first SRS on one or more of the third plurality of antenna ports at a first time instance. • Step 402: Receiving a configuration by the UE to receive the first and the second CSI- RS resources at a second time instance later than the first time instance and report a phase and/or timing offset based one the first and second CSI-RS resources, where the configuration comprising an indication of which one or more of the third plurality of antenna ports are to be used to receive the first and second CSI-RS resources. • Step 404: Transmitting by the UE the first SRS at the first time instance. • Step 406: Receiving by the gNB the first SRS at the first plurality of antenna ports and the second plurality of antenna ports. • Step 408: Transmitting, by the network, the first and second CSI-RS resources over the first and the second sets of antenna ports, respectively at the second time instance. • Step 410: Receiving, by the UE, the first and the second CSI-RS resources at the indicated one or more antenna ports. • Step 412: Computing, by the UE, a first and a second phase offsets and/or a first and a second timing offsets for the first TRP and the second TRP, respectively, based on the received first and the second CSI-RS resources at the indicated one of more antenna ports. • Step 414: Reporting, by the UE, to the gNB the phase offset and/or the timing offset. [0059] Some embodiments disclosed herein include signalling to a UE which one or more of the antenna ports at the UE should be used for receiving CSI-RS resources from multiple TRPs for computing and reporting a phase offset and/or a timing/delay offset between each of multiple TRPs and a reference TRP. [0060] In some embodiments, when the precoding matrix at each TRP for coherent joint downlink transmission is to be derived jointly based on an aggregated DL channel matrix across all configured TRPs, the UE may be indicated to use a single antenna port for receiving the CSI- RS resources from the multiple TRPs. The single antenna port should be the same as an antenna port used previously for transmitting an SRS. If the SRS is transmitted on multiple antenna ports, the single antenna port is one of the multiple antenna ports. [0061] In some embodiments, when the precoding matrix at each TRP for coherent joint downlink transmission is to be derived individually based on an estimated UL channel matrix of the corresponding TRP, the UE may be indicated to use all the antenna ports previously used for transmitting a SRS for receiving the CSI-RS resources from the multiple TRPs for phase and/or time offset estimation and feedback [0062] In some embodiments, the phase offset reported is per subband or a group of subcarriers for each TRP. [0063] Certain embodiments may provide one or more of the following technical advantages. The method enables feedback of proper phase and/or timing offsets for reciprocity based CJT in presence of timing offsets between TRPs. [0064] Note that, in 6^th Generation (6G), other terms than Non-Zero Power (NZP) CSI-RS might be used. For example, a new downlink reference signal or downlink synchronization signal might be introduced in 6G which can be used instead of NZP CSI-RS. The 6G downlink reference signals and/or downlink synchronization signals might be aperiodically, semi- persistently or periodically transmitted. In the following description, the terms “DL-RS”, “NZP CSI-RS” and “NZP CSI-RS resource set” may be used interchangeably. Also, although the term TRP is used in this disclosure, the term TRP may not be captured in 3GPP specifications. Instead, a TRP can be represented by any one of ‘NZP CSI-RS resource set’, ‘NZP CSI-RS resource’, ‘TRS resource set’, and/or ‘TRS resource’, or in general downlink reference signal (DL-RS). [0065] In reciprocity based CJT transmission to a UE, a rank and a precoding matrix associated to each of multiple TRPs are determined by the network based on uplink reference signals (RS) such as SRS or Demodulation Reference Signal (DMRS) transmitted from the UE. [0066] To be able to obtain DL channel estimation from UL channel estimation, the receive and transmit circuitries at each TRP is typically calibrated such that the same gain and phase are maintained across different receive and transmit circuitries associated to different antennas. There exists, however, an unknown residual absolute phase at each TRP after calibration. This means that there is an unknown phase difference between the estimated downlink channel and the actual DL channel. As a result, there is an unknown phase difference between any two estimated DL channels associated two TRPs in a system with multiple TRPs. _{[0067] An example is shown in Figure 5, where there are N TRPs. ^^^^^^^^^^^^,^^^^ (^^^^ = 1, ... ,^^^^), is the unknown absolute phase associated to the ith TRP. is the} wireless propagation channel associated to the i-th TRP, where ^^^^_{^^^^^^^^,^^^^^^^^} is the number of received antennas at the UE and ^^^^_{^^^^^^^^,^^^^^^^^^^^^} is the number of transmit antennas at each TRP. is the same for UL and DL due to channel reciprocity. The actual DL channel associated to the ith TRP is _{^^^^^^^^^^^^^^^^^^^^,^^^^^^^^^^^^. ^^^^^^^^ ∈ ^^^^^^^^^^^^^^^^,^^^^^^^^^^^^×^^^^ (^^^^ = 1, ... ,^^^^) is a precoding matrix to be applied to data ^^^^} in the ith TRP for joint DL data (e.g., PDSCH) transmission from the N TRPs, where ^^^^ is the rank or number of layers. _{[0068] To achieve coherent combining of signals from the N TRPs at the UE, {^^^^^^^^^^^^^^^^^^^^,1^^^^1, ^^^^ = 1, ... ,^^^^} needs to be estimated.} [0069] When each of the N TRPs also has a timing offset with respect to an ideal timing, ^^^^_{^^^^^^^^,^^^^} also contains a phase term which increases or decreases linearly over frequency or subcarriers. When there are also frequency offsets among the TRPs, ^^^^_{^^^^^^^^,^^^^} can also change over time. [0070] Figure 6 shows a timing diagram of UL transmission and reception at TRP#i. It is assumed that the UE is time locked to one of the TRPs in the DL, e.g., a reference TRP with time delay ^^^^₀. In the UL, the UE uses a time advance 2^^^^₀ for UL transmission such that it reaches _{the reference TRP at ^^^^0 + ^^^^^^^^^^^^, which is the start of the Fast Fourier Transform (FFT) window at} the reference TRP. ^^^^_^^^^^^^^ is the cyclic prefix. For TRP#i, in addition to a propagation delay ^^^^_^^^^, there is also an associated timing offset ∆^^^^_^^^^ with respect to the reference TRP and a frequency ^^^_^^_^^^ which may be different from the UE transmit frequency ^^^_^^_^^^^^^^ . The Inverse Fast Fourier Transform (IFFT)/FFT windows are the timings assumed by the UE and TRP for transmission and reception. For simplicity, the same timing is assumed for DL and UL at the TRPs. [0071] For reciprocity based CJT, there can be two approaches for obtaining the precoding _{matrices {^^^^^^^^, ^^^^ = In the first approach, {^^^^^^^^, ^^^^ = ^^^^, ... ,^^^^} are obtained jointly based} on an estimation of an aggregated DL channel matrix ^^^^ over all TRPs, i.e., _{For example, each column of ^^^^} is an eigen vector of ^^^^^{^^^^}^^^^, where co-phasing _{factors between TRPs are contained naturally in {^^^^^^^^ , ^^^^ = 1, … ,^^^^^^^^^^^^^^^^}.} [0072] For the first approach, the following steps, also illustrated in Figure 7A, can be used _{for obtaining the precoding matrices {^^^^^^^^ , ^^^^ = 1, … ,^^^^ }:} • Step 700: UE transmits SRS from all of its ^^^^_{^^^^^^^^,^^^^^^^^} antenna ports, either simultaneously or a subset of antenna ports at a time via antenna switching, to the N TRPs. • Step 702: gNB estimates UL channel at each TRP based on the SRS. • Step 704: gNB transmits a single port precoded CSI-RS from each of the N TRPs to the UE, wherein the precoding is associated to one of the SRS ports. The associated SRS port is indicated to the UE. • Steps 706a, 706b, and 706c: The UE receives (Step 706a) the CSI-RS on a same antenna port as the indicated SRS ports, and estimates (Step 706b) and feeds _{back/reports (Step 706c) a phase offset {∆^^^^^^^^, ^^^^ = 1, ... ,^^^^} and/or timing offset} associated to each TRP based on the received respective CSI-RS. • Step 708: gNB estimates the DL channel at each TRP based on the UL channel e_{stimation and the reported phase offset {∆^^^^^^^^, ^^^^ = 1, ... ,^^^^} and/or the timing offset.} • Step 710: gNB computes a joint precoder for joint transmission over the N TRPs based on an aggregated DL channel estimate across the N TRPs. [0073] While note explicitly shown in Figure 7A, as will be understood by those of ordinary skill in the art upon reading this disclosure, the UE may receive configuration information from the gNB as described above in relation to steps 400 and 402 of Figure 4. [0074] More details of the above steps are described below. [0075] Step 700: A high-level block diagram of UL transmission and reception is shown in _{Figure 7B. An SRS is transmitted from antenna port m�^^^^ the UE at time instance ^^^^′0 and is received at antenna port n�^^^^ ∈�1, … ,^^^^^^^^^^^^,^^^^^^^^^^^^�� of TRP#i at time instance ^^^^^^^^.} ^^^^_{^^^^^^^^,^^^^^^^^} is an unknown phase associated to the UE side transmit circuitry and is common to all UE transmit antennas. ^^^^_{^^^^^^^^,^^^^^^^^^^^^^^^^} is an unknown phase associated to the receive circuitry at TRP #i and is common to all receive antennas at TRP #i. ^^^^_^^^^(^^^^,^^^^,^^^^) is wireless propagation channel at subcarrier k from antenna port m at the UE to antenna port n at TRP #i, which is the same for both DL and UL. ^^^^_^^^^ is a propagation delay associated to TRP i, ^^^_^^_^^^^^^^ is the UE transmit frequency and ^^^_^^_^^^ is the receive frequency at TRP #i. [0076] Step 702: At the ith TRP, the estimated UL channel at subcarrier k between the mth antenna port at the UE and the nth antenna port at the TRP is given by where ^_{^^^^^^^ = ∑} ⁽ _{^^^^^^^^^^^^^^^^−1} ⁾ ^_{^^^=0 ^^^^^^^^^^^^(^^^^2^^^^(^^^^^^^^^^^^ − ^^^^^^^^)^^^^∆^^^^^^^^)} (eq.3a) ^^^^_^^^^^^^^^^^^ is the FFT (Fast Fourier Transform) size. ∆^^^_^^_^^^ is the sampling time interval. ^^^^_^^^^ and ^^^^₀ are the propagation delays associated to TRP #i and the reference TRP, respectively. ∆^^^_^^_^^^^^^^^^^^ is the subcarrier spacing. Observation: ^^^^_0,^^^^ is due to RF circuitry. −_{2^^^^^^^^^^^^^^^^^^^^^^^^ + 2^^^^^^^^∆^^^^^^^^^^^^^^^^(∆^^^^^^^^ + ^^^^0 − ^^^^^^^^) is due to the timing offset and propagation delay} difference between TRP #i and the reference TRP. _{+ ^^^^^^^^^^^^ is due to a frequency offset between TRP#i and the UE.} [0077] Step 704: Figure 7C is a block diagram of CSI-RS transmission from TRP#i for phase and/or timing offset feedback. ^^^^_{^^^^^^^^,^^^^^^^^} is an unknown phase associated to the UE side receive circuitry and is common to all UE receive antennas. ^^^^_{^^^^^^^^,^^^^^^^^^^^^^^^^} is an unknown phase associated to the transmit circuitry at TRP #i and is common to all transmit antennas at TRP #i. A single port CSI-RS is precoded and transmitted over the ^^^^_{^^^^^^^^,^^^^^^^^^^^^} antennas of each TRP at time _{instance ^^^^^^^^ + ^^^1^ . Note that different CSI-RS are transmitted from different TRPs. For TRP #i,} the CSI-RS in subcarrier k at antenna port n is precoded by ^^^^_{^^^^,^^^^^^^^^^^^−^^^^^^^^}(^^^^,^^^^,^^^^), which is given by ^_{^^^^^^^,^^^^^^^^^^^^−^^^^^^^^(^^^^,^^^^,^^^^) = ^^^^∗ ^^^^,^^^^^^^^(^^^^,^^^^, ^^^^) (eq.4) where (^^^^)∗ indicates the conjugate of ^^^^. Alternatively, ^^^^^^^^,^^^^^^^^^^^^−^^^^^^^^(^^^^,^^^^, ^^^^) =} ^^^^^^^^^^^^(−^^^^∠^^^^_{^^^^,^^^^^^^^}(^^^^,^^^^,^^^^). In the following, ^^^^_{^^^^,^^^^^^^^^^^^−^^^^^^^^}(^^^^,^^^^,^^^^) in eq.4 is assumed. Port ^^^^ is indicated to the UE. [0078] Steps 706a, 706b, and 706c: DL channel estimation associated to TRP #i based on the CSI-RS received on antenna port ^^^^ at the UE is given by where (eq.7c) ∆_{^^^^^^^^ = ^^^^^^^^ − ^^^^^^^^^^^^^^^^ , ^^^^^^^^^^^^^^^^ is the frequency of the reference TRP (eq.7d)} ∆_{′^^^^^^^^ = −2∆^^^^^^^^ (eq.7f) [0079] Note that ∆^^^^^^^^ + 2^^^^^^^^∆^^^^^^^^^^^^^^^^∆′^^^^^^^^ is the phase difference between the estimated DL} channel in Step 702 at ^^^^_^^^^ and the actual DL channel associated to TRP #i at ^^^^_^^^^ + ^^^₁^ . ∆^^^^_^^^^ contains phase differences due to the circuitry at the UE and TRP#i and due to the frequency difference between TRP #i and the UE. Item 2^^^^^^^^∆^^^_^^_^^^^^^^^^^^∆′^^^^_^^^^ ^^^^^^^^ ^^^^ue to the presence of timing error/offset ∆^^^^_^^^^ and varies linearly over subcarriers. _{[0080] {∆^^^^^^^^,∆′^^^^^^^^, ^^^^ = 1, ... ,^^^^} can be reported by the UE to the gNB. Alternatively, the UE can report are} associated to a reference TRP and are not reported. [0081] Note for a given precoder ^^^^_{^^^^,^^^^^^^^^^^^−^^^^^^^^}(^^^^,^^^^,^^^^), only CSI-RS received on antenna port ^^^^ can be used so that the effect of the channel’ phase is canceled out from the estimation ∆^^^^_^^^^.. _{[0082] Therefore, in one embodiment, information on antenna port ^^^^ ∈ [1, … ,^^^^^^^^^^^^,^^^^^^^^] is signalled to the UE for receiving the CSI-RS and for computing {∆^^^^^^^^,∆′^^^^^^^^, ^^^^ = 1, ... ,^^^^} or {∆^^^^^^^^ − ∆^^^^^^^^^^^^^^^^,∆′^^^^^^^^ − ∆′^^^^^^^^^^^^^^^^ , ^^^^ = 1, ... ,^^^^}. [0083] Step 708: When {∆^^^^^^^^,∆′^^^^^^^^, ^^^^ = 1, ... ,^^^^} are received at the gNB. An estimation of} the actual DL channel for TRP#i can be derived at the gNB as follows: ^_{�^^^^^^^,^^^^^^^^(^^^^,^^^^,^^^^) = ^^^^^^^^^^^^(^^^^∆^^^^^^^^ + ^^^^2^^^^^^^^∆^^^^^^^^^^^^^^^^∆′^^^^^^^^)^^^^^^^^,^^^^^^^^(^^^^,^^^^,^^^^) (eq.8) ^^^^^^^^^^^^)(^^^^^^^^ + ^^^^1) + ^^^^^^^^1,^^^^) (eq.10) [0084] Note that due to the frequency difference (^^^^^^^^ − ^^^^^^^^^^^^), ^^^^^^^^^^^^,^^^^(^^^^,^^^1^ ) depends on the time} at which the CSI-RS is transmitted. If a joint PDSCH transmission will occur at a future time _{instance ^^^^^^^^ + ^^^^2. The downlink channel at ^^^^^^^^ + ^^^^2 should be estimated and used for deriving a} precoder at each TRP for the PDSCH. This can be achieved by applying a phase correction to _{where ^^^^0(^^^^1,^^^^2) = −2^^^^^^^^^^^^^^^^(^^^^^^^^ + ^^^^1) − 2^^^^^^^^^^^^^^^^^^^^(^^^^2 − ^^^1^ ), which is common to all N TRPs and does not have any impact on precoder estimation. It is assumed above that ^^^^^^^^ − ^^^^^^^^^^^^^^^^ is known at} the gNB based on a separate procedure. _{[0085] Therefore, the actual DL channel at time ^^^^^^^^ + ^^^^2 at each TRP can be estimated based on the corresponding UL channel estimation {^^^^^^^^,^^^^^^^^(^^^^,^^^^,^^^^), ^^^^ = 1, ... ,^^^^} at time ^^^^^^^^, the phase and time offset feedback {∆^^^^^^^^,∆′^^^^^^^^, ^^^^ = 1, ... ,^^^^} measured at time ^^^^^^^^ + ^^^^1, and frequency offsets {^^^^^^^^ − ^^^^^^^^^^^^^^^^ ,} [0086] In some scenario, ∆^^^^_^^^^ may be calculated per subband. If both wideband and subband ∆^^^^_^^^^ are reported, the subband ∆^^^^_^^^^ may be differentially encoded with respect to the wideband ∆^^^^_^^^^ of the same TRP. [0087] Step 710: The aggregated DL channel at subcarrier k across all N TRPs at time _{^^^^^^^^ + ^^^^2 can be obtained as} (eq.16) _{Precoders {^^^^^^^^(^^^^), ^^^^ = 1, … ,^^^^^^^^^^^^^^^^ } at subcarrier k can be derived jointly based on For example, each column of ^^^^(^^^^)} is an eigen vector of . _{[0088] Alternatively, the subcarrier dependent term ^^^^^^^^^^^^(^^^^2^^^^^^^^∆^^^^^^^^^^^^^^^^(^^^^0 − ^^^^^^^^ − ∆^^^^^^^^)) in ^�^^^^^^^,^^^^^^^^,^^^^2(^^^^,^^^^,^^^^) can be precompensated if ^^^^^^^^ + ∆^^^^^^^^ − ^^^^0 is known. ^^^^^^^^ + ∆^^^^^^^^ − ^^^^0 is effectively} the downlink time delay difference between TRP #i and the reference TRP and can be estimated. _{Therefore, the precoders do not have to be computed per subcarrier. Typically, ^^^^^^^^(^^^^,^^^^, ^^^^) is} almost the same over a group of subcarriers or subband. The precoders can be computed per _{subband. The subcarrier dependent term ^^^^^^^^^^^^(^^^^2^^^^^^^^∆^^^^^^^^^^^^^^^^(^^^^0 − ^^^^^^^^ can be pre- compensated by applying ^^^^^^^^^^^^(−^^^^2^^^^^^^^∆^^^^^^^^^^^^^^^^(^^^^0 − ^^^^^^^^ − to a PDSCH to be transmitted at} TRP #i before precoding. _{[0089] In the second approach, {^^^^^^^^(^^^^), ^^^^ = 1, … ,^^^^^^^^^^^^^^^^ } are first derived individually at each TRP, i.e., ^^^^^^^^(^^^^) is derived based on the UL channel estimation ^^^^^^^^,^^^^^^^^(^^^^) = in Step 702 (specifically in corresponding step 802 of Figure 8). ^^^^^^^^(^^^^) is typically independent of ^^^^^^^^^^^^,^^^^(^^^^). In this case, direct estimating {∆^^^^^^^^, ^^^^ = 1, ... ,^^^^} is} not needed because the precoder ^^^^_^^^^(^^^^) does not depend on ∆^^^^_^^^^. Instead, a co-phasing factor ^^^^^^^^^^^^�^^^^^^^^_^^^^,^^^^�, may be estimated and feedback for layer l and TRP#i by the UE based a precoded CSI-RS, where ^^^^_^^^^ (k) is used to precode a CSI-RS at TRP #i. [0090] In the second approach, also illustrated in Figure 8, the following steps can be used for precoding a PDSCH for CJT: • Step 800: this step is the same as Step 700 of Figure 7A. UE transmits SRS from all of its ^^^^_{^^^^^^^^,^^^^^^^^} antenna ports. • Step 802: this step is the same as Step 702 of Figure 7A. gNB estimate UL channel at each TRP based on the SRS • Step 804: gNB derives a precoder at each TRP based on the UL channel estimation in Step 802. A precoded CSI-RS per layer is transmitted from each of the N TRPs to the UE. • Steps 806a, 806b, and 806c: The UE receives (Step 806a) the CSI-RS on all its receive antenna ports, and estimates (Step 806b) and feeds back/ reports (Step 806c) a co- phasing factor for each layer and each TRP. • Step 808: gNB applies the co-phasing factor to each precoder at each TRP. [0091] More details of the above steps are described below. _{[0092] Step 804: ^^^^^^^^(^^^^) ∈ ^^^^^^^^^^^^^^^^,^^^^^^^^^^^^×^^^^ is derived based on the UL channel estimation ^^^^^^^^,^^^^^^^^(^^^^) = |^^^^^^^^|^^^^^^^^(^^^^)^^^^^^^^^^^^�^^^^^^^^^^^^^^^^,^^^^(^^^^)� obtained in Step 802, where ^^^^ is rank which is the same for all the N TRPs. A precoded CSI-RS is transmitted from each TRP at time instance ^^^^^^^^ + ^^^1^ .} For TRP #i, the CSI-RS is precoded with ^^^^_^^^^(^^^^). There are ^^^^ CSI-RS ports, one per layer. [0093] Steps 806a, 806b, and 806c: The precoded CSI-RS from all the N TRPs are received on all receive antennas at the UE. The estimated DL channel associated to TRP #i based on the precoded CSI-RS is then ^_{^^^^^^^,^^^^^^^^(^^^^) = |^^^^^^^^|^^^^^^^^(^^^^)^^^^^^^^(^^^^)^^^^^^^^^^^^(^^^^^^^^^^^^^^^^,^^^^(^^^^,^^^1^ )) (eq. 17)} where _{[0094] Note that 2^^^^^^^^∆^^^^^^^^^^^^^^^^(^^^^0 − ^^^^^^^^ − is due to timing offset and propagation delay, and (^^^^0 − ^^^^^^^^ − ∆^^^^^^^^) can be estimated by the UE based on ^^^^^^^^,^^^^^^^^(^^^^) and feedback. Therefore, for co- phasing factor estimation, 2^^^^^^^^∆^^^^^^^^^^^^^^^^(^^^^0 − ^^^^^^^^ − ∆^^^^^^^^) can be removed from ^^^^^^^^^^^^,^^^^(^^^^,^^^1^ ) and ^^^^^^^^(^^^^) = |^^^^^^^^|^^^^^^^^(^^^^)^^^^^^^^(^^^^)^^^^^^^^^^^^(^^^^^^^^^^^^^^^^,^^^^(^^^1^ )) can be used. [0095] The co-phasing factors for layer ^^^^ ∈ (1, ... , ^^^^) can be represented by a complex vector} is the co-phasing factor for layer ^^^^ at TRP Here for simplicity, the first TRP is denoted as the reference TRP. [0096] ^^^^_^^^^(^^^^) can be determined at the UE by maximizing the following utility function. [0097] Since ^^^^_{^^^^^^^^,^^^^}(^^^^₁) is a constant across subcarriers, computing co-phasing factors per subcarrier is generally not needed and a wideband co-phasing factor per layer per TRP or a co- phasing factor per subband per layer per TRP should be adequate. Therefore, a wideband co- phasing factor per layer per TRP and/or a co-phasing factor per subband per layer per TRP can _{be feedback together with a timing offset (^^^^^^^^ + ∆^^^^^^^^ − ^^^^0) , feedback per TRP. If both wideband} and subband co-phasing are reported, the phase of subband co-phasing factor may be differentially encoded with respect to phase of the wideband co-phase factor of the same layer and TRP.. [0098] Step 808: The precoder for PDSCH can be determined by applying the co-phasing _{factors to {^^^^^^^^(^^^^), ^^^^ = 1, … ,^^^^^^^^^^^^^^^^ }. Let} precoding vector for the ^^^^th layer, then the precoding matrix for PDSCH at TRP [0099] Note that for both the first and the second approaches, the UE is configured with N CSI-RS resources, one per TRP, for phase and/or timing offsets feedback. In the first approach, only a single antenna port is used at the UE for receiving the single port CSI-RS, and estimate and feeds back a phase offset and/or timing offset per CSI-RS resource. The single antenna port needs to be indicated to the UE. [0100] In the second approach, the same UE receive antenna ports for receiving a PDSCH are used for receiving the CSI-RS, wherein the CSI-RS may have multiple CSI-RS ports, each associated to a layer. The UE estimates and feeds back a co-phase factor per CSI-RS port per TRP and/or a timing offset per TRP. [0101] The same CSI report configuration may be used for both the first and the second approaches, where multiple CSI-RS resources are configured for channel measurement and phase and/timing offsets are to be reported. The CSI report configuration may further contain information about which one or more antenna ports at the UE for the measurement. The first approach is indicated when a single antenna port is indicated and the CSI-RS resources each has a single CSI-RS port. The second approach may be indicated when the CSI-RS resources each has multiple CSI-RS ports and either multiple antenna ports are indicated or nor antenna port is indicated. [0102] Figure 9 shows an example of a communication system 900 in accordance with some embodiments. [0103] In the example, the communication system 900 includes a telecommunication network 902 that includes an access network 904, such as a Radio Access Network (RAN), and a core network 906, which includes one or more core network nodes 908. The access network 904 includes one or more access network nodes, such as network nodes 910A and 910B (one or more of which may be generally referred to as network nodes 910), or any other similar Third Generation Partnership Project (3GPP) access nodes or non-3GPP Access Points (APs). Moreover, as will be appreciated by those of skill in the art, a network node is not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that network nodes include disaggregated implementations or portions thereof. For example, in some embodiments, the telecommunication network 902 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network 902 that supports an ORAN specification (e.g., a specification published by the O-RAN Alliance, or any similar organization) and may operate alone or together with other nodes to implement one or more functionalities of any node in the telecommunication network 902, including one or more network nodes 910 and/or core network nodes 908. [0104] Examples of an ORAN network node include an Open Radio Unit (O-RU), an Open Distributed Unit (O-DU), an Open Central Unit (O-CU), including an O-CU Control Plane (O- CU-CP) or an O-CU User Plane (O-CU-UP), a RAN intelligent controller (near-real time or non- real time) hosting software or software plug-ins, such as a near-real time control application (e.g., xApp) or a non-real time control application (e.g., rApp), or any combination thereof (the adjective “open” designating support of an ORAN specification). The network node may support a specification by, for example, supporting an interface defined by the ORAN specification, such as an A1, F1, W1, E1, E2, X2, Xn interface, an open fronthaul user plane interface, or an open fronthaul management plane interface. Moreover, an ORAN access node may be a logical node in a physical node. Furthermore, an ORAN network node may be implemented in a virtualization environment (described further below) in which one or more network functions are virtualized. For example, the virtualization environment may include an O-Cloud computing platform orchestrated by a Service Management and Orchestration Framework via an O-2 interface defined by the O-RAN Alliance or comparable technologies. The network nodes 910 facilitate direct or indirect connection of User Equipment (UE), such as by connecting UEs 912A, 912B, 912C, and 912D (one or more of which may be generally referred to as UEs 912) to the core network 906 over one or more wireless connections. [0105] Example wireless communications over a wireless connection include transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 900 may include any number of wired or wireless networks, network nodes, UEs, and/or any other components or systems that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections. The communication system 900 may include and/or interface with any type of communication, telecommunication, data, cellular, radio network, and/or other similar type of system. [0106] The UEs 912 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and/or operable to communicate wirelessly with the network nodes 910 and other communication devices. Similarly, the network nodes 910 are arranged, capable, configured, and/or operable to communicate directly or indirectly with the UEs 912 and/or with other network nodes or equipment in the telecommunication network 902 to enable and/or provide network access, such as wireless network access, and/or to perform other functions, such as administration in the telecommunication network 902. [0107] In the depicted example, the core network 906 connects the network nodes 910 to one or more hosts, such as host 916. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 906 includes one more core network nodes (e.g., core network node 908) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and/or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 908. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-Concealing Function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and/or a User Plane Function (UPF). [0108] The host 916 may be under the ownership or control of a service provider other than an operator or provider of the access network 904 and/or the telecommunication network 902, and may be operated by the service provider or on behalf of the service provider. The host 916 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio/video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server. [0109] As a whole, the communication system 900 of Figure 9 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system 900 may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and/or other suitable Second, Third, Fourth, or Fifth Generation (2G, 3G, 4G, or 5G) standards, or any applicable future generation standard (e.g., Sixth Generation (6G)); Wireless Local Area Network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and/or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and/or any Low Power Wide Area Network (LPWAN) standards such as LoRa and Sigfox. [0110] In some examples, the telecommunication network 902 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunication network 902 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 902. For example, the telecommunication network 902 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing enhanced Mobile Broadband (eMBB) services to other UEs, and/or massive Machine Type Communication (mMTC)/massive Internet of Things (IoT) services to yet further UEs. [0111] In some examples, the UEs 912 are configured to transmit and/or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 904 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 904. Additionally, a UE may be configured for operating in single- or multi-Radio Access Technology (RAT) or multi-standard mode. For example, a UE may operate with any one or combination of WiFi, New Radio (NR), and LTE, i.e. being configured for Multi-Radio Dual Connectivity (MR-DC), such as Evolved UMTS Terrestrial RAN (E-UTRAN) NR - Dual Connectivity (EN-DC). [0112] In the example, a hub 914 communicates with the access network 904 to facilitate indirect communication between one or more UEs (e.g., UE 912C and/or 912D) and network nodes (e.g., network node 910B). In some examples, the hub 914 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 914 may be a broadband router enabling access to the core network 906 for the UEs. As another example, the hub 914 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 910, or by executable code, script, process, or other instructions in the hub 914. As another example, the hub 914 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 914 may be a content source. For example, for a UE that is a Virtual Reality (VR) headset, display, loudspeaker or other media delivery device, the hub 914 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 914 then provides to the UE either directly, after performing local processing, and/or after adding additional local content. In still another example, the hub 914 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy IoT devices. [0113] The hub 914 may have a constant/persistent or intermittent connection to the network node 910B. The hub 914 may also allow for a different communication scheme and/or schedule between the hub 914 and UEs (e.g., UE 912C and/or 912D), and between the hub 914 and the core network 906. In other examples, the hub 914 is connected to the core network 906 and/or one or more UEs via a wired connection. Moreover, the hub 914 may be configured to connect to a Machine-to-Machine (M2M) service provider over the access network 904 and/or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 910 while still connected via the hub 914 via a wired or wireless connection. In some embodiments, the hub 914 may be a dedicated hub – that is, a hub whose primary function is to route communications to/from the UEs from/to the network node 910B. In other embodiments, the hub 914 may be a non-dedicated hub – that is, a device which is capable of operating to route communications between the UEs and the network node 910B, but which is additionally capable of operating as a communication start and/or end point for certain data channels. [0114] Figure 10 shows a UE 1000 in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged, and/or operable to communicate wirelessly with network nodes and/or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, Voice over Internet Protocol (VoIP) phone, wireless local loop phone, desktop computer, Personal Digital Assistant (PDA), wireless camera, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, Laptop Embedded Equipment (LEE), Laptop Mounted Equipment (LME), smart device, wireless Customer Premise Equipment (CPE), vehicle, vehicle-mounted or vehicle embedded/integrated wireless device, etc. Other examples include any UE identified by the 3GPP, including a Narrowband Internet of Things (NB-IoT) UE, a Machine Type Communication (MTC) UE, and/or an enhanced MTC (eMTC) UE. [0115] A UE may support Device-to-Device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), Vehicle-to-Vehicle (V2V), Vehicle-to-Infrastructure (V2I), or Vehicle- to-Everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and/or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter). [0116] The UE 1000 includes processing circuitry 1002 that is operatively coupled via a bus 1004 to an input/output interface 1006, a power source 1008, memory 1010, a communication interface 1012, and/or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 10. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc. [0117] The processing circuitry 1002 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 1010. The processing circuitry 1002 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, Field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general purpose processors, such as a microprocessor or Digital Signal Processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 1002 may include multiple Central Processing Units (CPUs). [0118] In the example, the input/output interface 1006 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and/or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE 1000. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device. [0119] In some embodiments, the power source 1008 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source 1008 may further include power circuitry for delivering power from the power source 1008 itself, and/or an external power source, to the various parts of the UE 1000 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 1008. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 1008 to make the power suitable for the respective components of the UE 1000 to which power is supplied. [0120] The memory 1010 may be or be configured to include memory such as Random Access Memory (RAM), Read Only Memory (ROM), Programmable ROM (PROM), Erasable PROM (EPROM), Electrically EPROM (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 1010 includes one or more application programs 1014, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 1016. The memory 1010 may store, for use by the UE 1000, any of a variety of various operating systems or combinations of operating systems. [0121] The memory 1010 may be configured to include a number of physical drive units, such as Redundant Array of Independent Disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, High Density Digital Versatile Disc (HD- DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, Holographic Digital Data Storage (HDDS) optical disc drive, external mini Dual In-line Memory Module (DIMM), Synchronous Dynamic RAM (SDRAM), external micro-DIMM SDRAM, smartcard memory such as a tamper resistant module in the form of a Universal Integrated Circuit Card (UICC) including one or more Subscriber Identity Modules (SIMs), such as a Universal SIM (USIM) and/or Internet Protocol Multimedia Services Identity Module (ISIM), other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as a ‘SIM card.’ The memory 1010 may allow the UE 1000 to access instructions, application programs, and the like stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system, may be tangibly embodied as or in the memory 1010, which may be or comprise a device-readable storage medium. [0122] The processing circuitry 1002 may be configured to communicate with an access network or other network using the communication interface 1012. The communication interface 1012 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 1022. The communication interface 1012 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network). Each transceiver may include a transmitter 1018 and/or a receiver 1020 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 1018 and receiver 1020 may be coupled to one or more antennas (e.g., the antenna 1022) and may share circuit components, software, or firmware, or alternatively be implemented separately. [0123] In the illustrated embodiment, communication functions of the communication interface 1012 may include cellular communication, WiFi communication, LPWAN communication, data communication, voice communication, multimedia communication, short- range communications such as Bluetooth, NFC, location-based communication such as the use of the Global Positioning System (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented according to one or more communication protocols and/or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband CDMA (WCDMA), GSM, LTE, NR, UMTS, WiMax, Ethernet, Transmission Control Protocol/Internet Protocol (TCP/IP), Synchronous Optical Networking (SONET), Asynchronous Transfer Mode (ATM), Quick User Datagram Protocol Internet Connection (QUIC), Hypertext Transfer Protocol (HTTP), and so forth. [0124] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 1012, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient). [0125] As another example, a UE comprises an actuator, a motor, or a switch related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or to a robotic arm performing a medical procedure according to the received input. [0126] A UE, when in the form of an IoT device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application, and healthcare. Non-limiting examples of such an IoT device are a device which is or which is embedded in: a connected refrigerator or freezer, a television, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door/window sensor, a flood/moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or VR, a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an IoT device comprises circuitry and/or software in dependence of the intended application of the IoT device in addition to other components as described in relation to the UE 1000 shown in Figure 10. [0127] As yet another specific example, in an IoT scenario, a UE may represent a machine or other device that performs monitoring and/or measurements and transmits the results of such monitoring and/or measurements to another UE and/or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship, an airplane, or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation. [0128] In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g., by controlling an actuator) to increase or decrease the drone’s speed. The first and/or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator and handle communication of data for both the speed sensor and the actuators. [0129] Figure 11 shows a network node 1100 in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged, and/or operable to communicate directly or indirectly with a UE and/or with other network nodes or equipment in a telecommunication network. Examples of network nodes include, but are not limited to, APs (e.g., radio APs), Base Stations (BSs) (e.g., radio BSs, Node Bs, evolved Node Bs (eNBs), NR Node Bs (gNBs)), and O-RAN nodes or components of an O-RAN node (e.g., O-RU, O-DU, O- CU). [0130] Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units, distributed units (e.g., in an O-RAN access node), and/or Remote Radio Units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such RRUs may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a Distributed Antenna System (DAS). [0131] Other examples of network nodes include multiple Transmission Point (multi-TRP) 5G access nodes, Multi-Standard Radio (MSR) equipment such as MSR BSs, network controllers such as Radio Network Controllers (RNCs) or BS Controllers (BSCs), Base Transceiver Stations (BTSs), transmission points, transmission nodes, Multi-Cell/Multicast Coordination Entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and/or Minimization of Drive Tests (MDTs). [0132] The network node 1100 includes processing circuitry 1102, memory 1104, a communication interface 1106, and a power source 1108. The network node 1100 may be composed of multiple physically separate components (e.g., a NodeB component and an RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node 1100 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair may in some instances be considered a single separate network node. In some embodiments, the network node 1100 may be configured to support multiple RATs. In such embodiments, some components may be duplicated (e.g., separate memory 1104 for different RATs) and some components may be reused (e.g., a same antenna 1110 may be shared by different RATs). The network node 1100 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 1100, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, Long Range Wide Area Network (LoRaWAN), Radio Frequency Identification (RFID), or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within the network node 1100. [0133] The processing circuitry 1102 may comprise a combination of one or more of a microprocessor, controller, microcontroller, CPU, DSP, ASIC, FPGA, or any other suitable computing device, resource, or combination of hardware, software, and/or encoded logic operable to provide, either alone or in conjunction with other network node 1100 components, such as the memory 1104, to provide network node 1100 functionality. [0134] In some embodiments, the processing circuitry 1102 includes a System on a Chip (SOC). In some embodiments, the processing circuitry 1102 includes one or more of Radio Frequency (RF) transceiver circuitry 1112 and baseband processing circuitry 1114. In some embodiments, the RF transceiver circuitry 1112 and the baseband processing circuitry 1114 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of the RF transceiver circuitry 1112 and the baseband processing circuitry 1114 may be on the same chip or set of chips, boards, or units. [0135] The memory 1104 may comprise any form of volatile or non-volatile computer- readable memory including, without limitation, persistent storage, solid state memory, remotely mounted memory, magnetic media, optical media, RAM, ROM, mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD), or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device-readable, and/or computer-executable memory devices that store information, data, and/or instructions that may be used by the processing circuitry 1102. The memory 1104 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and/or other instructions capable of being executed by the processing circuitry 1102 and utilized by the network node 1100. The memory 1104 may be used to store any calculations made by the processing circuitry 1102 and/or any data received via the communication interface 1106. In some embodiments, the processing circuitry 1102 and the memory 1104 are integrated. [0136] The communication interface 1106 is used in wired or wireless communication of signaling and/or data between a network node, access network, and/or UE. As illustrated, the communication interface 1106 comprises port(s)/terminal(s) 1116 to send and receive data, for example to and from a network over a wired connection. The communication interface 1106 also includes radio front-end circuitry 1118 that may be coupled to, or in certain embodiments a part of, the antenna 1110. The radio front-end circuitry 1118 comprises filters 1120 and amplifiers 1122. The radio front-end circuitry 1118 may be connected to the antenna 1110 and the processing circuitry 1102. The radio front-end circuitry 1118 may be configured to condition signals communicated between the antenna 1110 and the processing circuitry 1102. The radio front-end circuitry 1118 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 1118 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of the filters 1120 and/or the amplifiers 1122. The radio signal may then be transmitted via the antenna 1110. Similarly, when receiving data, the antenna 1110 may collect radio signals which are then converted into digital data by the radio front-end circuitry 1118. The digital data may be passed to the processing circuitry 1102. In other embodiments, the communication interface 1106 may comprise different components and/or different combinations of components. [0137] In certain alternative embodiments, the network node 1100 does not include separate radio front-end circuitry 1118; instead, the processing circuitry 1102 includes radio front-end circuitry and is connected to the antenna 1110. Similarly, in some embodiments, all or some of the RF transceiver circuitry 1112 is part of the communication interface 1106. In still other embodiments, the communication interface 1106 includes the one or more ports or terminals 1116, the radio front-end circuitry 1118, and the RF transceiver circuitry 1112 as part of a radio unit (not shown), and the communication interface 1106 communicates with the baseband processing circuitry 1114, which is part of a digital unit (not shown). [0138] The antenna 1110 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. The antenna 1110 may be coupled to the radio front-end circuitry 1118 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In certain embodiments, the antenna 1110 is separate from the network node 1100 and connectable to the network node 1100 through an interface or port. [0139] The antenna 1110, the communication interface 1106, and/or the processing circuitry 1102 may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by the network node 1100. Any information, data, and/or signals may be received from a UE, another network node, and/or any other network equipment. Similarly, the antenna 1110, the communication interface 1106, and/or the processing circuitry 1102 may be configured to perform any transmitting operations described herein as being performed by the network node 1100. Any information, data, and/or signals may be transmitted to a UE, another network node, and/or any other network equipment. [0140] The power source 1108 provides power to the various components of the network node 1100 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 1108 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 1100 with power for performing the functionality described herein. For example, the network node 1100 may be connectable to an external power source (e.g., the power grid or an electricity outlet) via input circuitry or an interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 1108. As a further example, the power source 1108 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail. [0141] Embodiments of the network node 1100 may include additional components beyond those shown in Figure 11 for providing certain aspects of the network node’s functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein. For example, the network node 1100 may include user interface equipment to allow input of information into the network node 1100 and to allow output of information from the network node 1100. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 1100. [0142] Figure 12 is a block diagram of a host 1200, which may be an embodiment of the host 916 of Figure 9, in accordance with various aspects described herein. As used herein, the host 1200 may be or comprise various combinations of hardware and/or software including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm. The host 1200 may provide one or more services to one or more UEs. [0143] The host 1200 includes processing circuitry 1202 that is operatively coupled via a bus 1204 to an input/output interface 1206, a network interface 1208, a power source 1210, and memory 1212. Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such as Figures 10 and 11, such that the descriptions thereof are generally applicable to the corresponding components of the host 1200. [0144] The memory 1212 may include one or more computer programs including one or more host application programs 1214 and data 1216, which may include user data, e.g. data generated by a UE for the host 1200 or data generated by the host 1200 for a UE. Embodiments of the host 1200 may utilize only a subset or all of the components shown. The host application programs 1214 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), Moving Picture Experts Group (MPEG), VP9) and audio codecs (e.g., Free Lossless Audio Codec (FLAC), Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers, wearable display systems, and heads-up display systems). The host application programs 1214 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network. Accordingly, the host 1200 may select and/or indicate a different host for Over-The-Top (OTT) services for a UE. The host application programs 1214 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (DASH or MPEG-DASH), etc. [0145] Figure 13 is a block diagram illustrating a virtualization environment 1300 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices, and networking resources. As used herein, virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more Virtual Machines (VMs) implemented in one or more virtual environments 1300 hosted by one or more of hardware nodes, such as a hardware computing device that operates as a network node, UE, core network node, or host. Further, in embodiments in which the virtual node does not require radio connectivity (e.g., a core network node or host), then the node may be entirely virtualized. In some embodiments, the virtualization environment 1300 includes components defined by the O-RAN Alliance, such as an O-Cloud environment orchestrated by a Service Management and Orchestration Framework via an O-2 interface. [0146] Applications 1302 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment 1300 to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein. [0147] Hardware 1304 includes processing circuitry, memory that stores software and/or instructions executable by hardware processing circuitry, and/or other hardware devices as described herein, such as a network interface, input/output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers 1306 (also referred to as hypervisors or VM Monitors (VMMs)), provide VMs 1308A and 1308B (one or more of which may be generally referred to as VMs 1308), and/or perform any of the functions, features, and/or benefits described in relation with some embodiments described herein. The virtualization layer 1306 may present a virtual operating platform that appears like networking hardware to the VMs 1308. [0148] The VMs 1308 comprise virtual processing, virtual memory, virtual networking, or interface and virtual storage, and may be run by a corresponding virtualization layer 1306. Different embodiments of the instance of a virtual appliance 1302 may be implemented on one or more of the VMs 1308, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as Network Function Virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers and customer premise equipment. [0149] In the context of NFV, a VM 1308 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs 1308, and that part of the hardware 1304 that executes that VM, be it hardware dedicated to that VM and/or hardware shared by that VM with others of the VMs 1308, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more VMs 1308 on top of the hardware 1304 and corresponds to the application 1302. [0150] The hardware 1304 may be implemented in a standalone network node with generic or specific components. The hardware 1304 may implement some functions via virtualization. Alternatively, the hardware 1304 may be part of a larger cluster of hardware (e.g., such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 1310, which, among others, oversees lifecycle management of the applications 1302. In some embodiments, the hardware 1304 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a RAN or a base station. In some embodiments, some signaling can be provided with the use of a control system 1312 which may alternatively be used for communication between hardware nodes and radio units. [0151] Figure 14 shows a communication diagram of a host 1402 communicating via a network node 1404 with a UE 1406 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as the UE 912A of Figure 9 and/or the UE 1000 of Figure 10), the network node (such as the network node 910A of Figure 9 and/or the network node 1100 of Figure 11), and the host (such as the host 916 of Figure 9 and/or the host 1200 of Figure 12) discussed in the preceding paragraphs will now be described with reference to Figure 14. [0152] Like the host 1200, embodiments of the host 1402 include hardware, such as a communication interface, processing circuitry, and memory. The host 1402 also includes software, which is stored in or is accessible by the host 1402 and executable by the processing circuitry. The software includes a host application that may be operable to provide a service to a remote user, such as the UE 1406 connecting via an OTT connection 1450 extending between the UE 1406 and the host 1402. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 1450. [0153] The network node 1404 includes hardware enabling it to communicate with the host 1402 and the UE 1406. The connection 1460 may be direct or pass through a core network (like the core network 906 of Figure 9) and/or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network may be a backbone network or the Internet. [0154] The UE 1406 includes hardware and software, which is stored in or accessible by the UE 1406 and executable by the UE’s processing circuitry. The software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via the UE 1406 with the support of the host 1402. In the host 1402, an executing host application may communicate with the executing client application via the OTT connection 1450 terminating at the UE 1406 and the host 1402. In providing the service to the user, the UE's client application may receive request data from the host's host application and provide user data in response to the request data. The OTT connection 1450 may transfer both the request data and the user data. The UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection 1450. [0155] The OTT connection 1450 may extend via the connection 1460 between the host 1402 and the network node 1404 and via a wireless connection 1470 between the network node 1404 and the UE 1406 to provide the connection between the host 1402 and the UE 1406. The connection 1460 and the wireless connection 1470, over which the OTT connection 1450 may be provided, have been drawn abstractly to illustrate the communication between the host 1402 and the UE 1406 via the network node 1404, without explicit reference to any intermediary devices and the precise routing of messages via these devices. [0156] As an example of transmitting data via the OTT connection 1450, in step 1408, the host 1402 provides user data, which may be performed by executing a host application. In some embodiments, the user data is associated with a particular human user interacting with the UE 1406. In other embodiments, the user data is associated with a UE 1406 that shares data with the host 1402 without explicit human interaction. In step 1410, the host 1402 initiates a transmission carrying the user data towards the UE 1406. The host 1402 may initiate the transmission responsive to a request transmitted by the UE 1406. The request may be caused by human interaction with the UE 1406 or by operation of the client application executing on the UE 1406. The transmission may pass via the network node 1404 in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 1412, the network node 1404 transmits to the UE 1406 the user data that was carried in the transmission that the host 1402 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 1414, the UE 1406 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 1406 associated with the host application executed by the host 1402. [0157] In some examples, the UE 1406 executes a client application which provides user data to the host 1402. The user data may be provided in reaction or response to the data received from the host 1402. Accordingly, in step 1416, the UE 1406 may provide user data, which may be performed by executing the client application. In providing the user data, the client application may further consider user input received from the user via an input/output interface of the UE 1406. Regardless of the specific manner in which the user data was provided, the UE 1406 initiates, in step 1418, transmission of the user data towards the host 1402 via the network node 1404. In step 1420, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 1404 receives user data from the UE 1406 and initiates transmission of the received user data towards the host 1402. In step 1422, the host 1402 receives the user data carried in the transmission initiated by the UE 1406. [0158] One or more of the various embodiments improve the performance of OTT services provided to the UE 1406 using the OTT connection 1450, in which the wireless connection 1470 forms the last segment. More precisely, the teachings of these embodiments may improve the e.g., data rate, latency, power consumption, etc. and thereby provide benefits such as e.g., reduced user waiting time, relaxed restriction on file size, improved content resolution, better responsiveness, extended battery lifetime, etc. [0159] In an example scenario, factory status information may be collected and analyzed by the host 1402. As another example, the host 1402 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 1402 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, the host 1402 may store surveillance video uploaded by a UE. As another example, the host 1402 may store or control access to media content such as video, audio, VR, or AR which it can broadcast, multicast, or unicast to UEs. As other examples, the host 1402 may be used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing, and/or transmitting data. [0160] In some examples, a measurement procedure may be provided for the purpose of monitoring data rate, latency, and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 1450 between the host 1402 and the UE 1406 in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 1450 may be implemented in software and hardware of the host 1402 and/or the UE 1406. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 1450 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or by supplying values of other physical quantities from which software may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 1450 may include message format, retransmission settings, preferred routing, etc.; the reconfiguring need not directly alter the operation of the network node 1404. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency, and the like by the host 1402. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 1450 while monitoring propagation times, errors, etc. [0161] Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and/or software needed to perform the tasks, features, functions, and methods disclosed herein. Determining, calculating, obtaining, or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box or nested within multiple boxes, in practice computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and/or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware. [0162] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer- readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hardwired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer- readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole and/or by end users and a wireless network generally. [0163] Those skilled in the art will recognize improvements and modifications to the embodiments of the present disclosure. All such improvements and modifications are considered within the scope of the concepts disclosed herein. [0164] Some exemplary embodiments of the present disclosure are as follows: Group A Embodiments [0165] Embodiment 1: A method performed by a user equipment, the method comprising one or more of: • transmitting SRS from all of the antenna ports, optionally the transmitting being either simultaneously or from a subset of antenna ports at a time via antenna switching, to the N TRPs • receiving a configuration of multiple NZP CSI-RS resources, each associated to a TRP, for channel measurement; • receiving a single port precoded CSI-RS from each of the N TRPs, wherein the precoding is associated to one of the SRS ports; • receiving the CSI-RS on a same antenna port as the one of the SRS ports; • estimating a phase difference between the transmit and receive chains based on the received CSI-RS; and • transmitting the phase difference. [0166] Embodiment 2: A method performed by a user equipment, the method comprising one or more of: • transmitting SRS from all of the antenna ports, optionally the transmitting being either simultaneously or from a subset of antenna ports at a time via antenna switching, to the N TRPs • receiving a precoded CSI-RS per layer is transmitted from each of the N TRPs; • receiving the CSI-RS on all its antenna ports; • estimating a co-phasing factor for each layer and each TRP; and • transmitting the co-phasing factor. [0167] Embodiment 3: The method of any of the previous embodiments, further comprising: • providing user data; and • forwarding the user data to a host via the transmission to the network node. Group B Embodiments [0168] Embodiment 4: A method performed by a network node, the method comprising one or more of: • receiving SRS from all antenna ports of a wireless device, either simultaneously or from a subset of antenna ports at a time via antenna switching, at N TRPs • estimating UL channel at each TRP based on the SRS; • transmitting a single port precoded CSI-RS from each of the N TRPs to the wireless device, wherein the precoding is associated to one of the SRS ports; • receiving a phase difference between the transmit and receive chains based on the received CSI-RS; • estimating the DL channel at each TRP based on the UL channel estimation; and • determining a joint precoder for the N TRPs based on an aggregated DL channel estimate across the N TRPs. [0169] Embodiment 5: A method performed by a network node, the method comprising one or more of: • receiving SRS from all antenna ports of a wireless device, either simultaneously or from a subset of antenna ports at a time via antenna switching, at N TRPs • estimating UL channel at each TRP based on the SRS; • determining a precoder at each TRP based on the UL channel estimation; • transmitting a precoded CSI-RS per layer is transmitted from each of the N TRPs to the wireless device; • receiving a co-phasing factor for each layer and each TRP; and • applying applies the co-phasing factor to each precoder at each TRP. [0170] Embodiment 6: The method of the previous embodiment further including any of the features of the Group A Embodiments or any other embodiments included herein. [0171] Embodiment 7: The method of any of the previous embodiments, further comprising: • obtaining user data; and • forwarding the user data to a host or a user equipment. Group C Embodiments [0172] Embodiment 8: A user equipment, comprising: • processing circuitry configured to perform any of the steps of any of the Group A embodiments; and • power supply circuitry configured to supply power to the processing circuitry. [0173] Embodiment 9: A network node, the network node comprising: • processing circuitry configured to perform any of the steps of any of the Group B embodiments; and • power supply circuitry configured to supply power to the processing circuitry. [0174] Embodiment 10: A user equipment (UE), the UE comprising: • an antenna configured to send and receive wireless signals; • radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry; • the processing circuitry being configured to perform any of the steps of any of the Group A embodiments; • an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry; • an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and • a battery connected to the processing circuitry and configured to supply power to the UE. [0175] Embodiment 11: A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: • processing circuitry configured to provide user data; and • a network interface configured to initiate transmission of the user data to a network node in a cellular network for transmission to a user equipment (UE), the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. [0176] Embodiment 12: The host of the previous embodiment, wherein: • the processing circuitry of the host is configured to execute a host application that provides the user data; and • the UE comprises processing circuitry configured to execute a client application associated with the host application to receive the transmission of user data from the host. [0177] Embodiment 13: A method implemented in a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: • providing user data for the UE; and • initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the network node performs any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. [0178] Embodiment 14: The method of the previous embodiment, further comprising, at the network node, transmitting the user data provided by the host for the UE. [0179] Embodiment 15: The method of any of the previous 2 embodiments, wherein the user data is provided at the host by executing a host application that interacts with a client application executing on the UE, the client application being associated with the host application. [0180] Embodiment 16: A communication system configured to provide an over-the-top (OTT) service, the communication system comprising: • a host comprising: • processing circuitry configured to provide user data for a user equipment (UE), the user data being associated with the over-the-top service; and • a network interface configured to initiate transmission of the user data toward a cellular network node for transmission to the UE, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. [0181] Embodiment 17: The communication system of the previous embodiment, further comprising: • the network node; and/or • the UE. [0182] Embodiment 18: A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: • processing circuitry configured to initiate receipt of user data; and • a network interface configured to receive the user data from a network node in a cellular network, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to receive the user data from a user equipment (UE) for the host. [0183] Embodiment 19: The host of the previous 2 embodiments, wherein: • the processing circuitry of the host is configured to execute a host application that receives the user data; and • the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application. [0184] Embodiment 20: The host of the any of the previous 2 embodiments, wherein the initiating receipt of the user data comprises requesting the user data. [0185] Embodiment 21: A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: • at the host, initiating receipt of user data from the UE, the user data originating from a transmission which the network node has received from the UE, wherein the network node performs any of the steps of any of the Group B embodiments to receive the user data from the UE for the host. [0186] Embodiment 22: The method of the previous embodiment, further comprising at the network node, transmitting the received user data to the host. [0187] Embodiment 23: A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: • processing circuitry configured to provide user data; and • a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the operations of any of the Group A embodiments to receive the user data from the host. [0188] Embodiment 24: The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data to the UE from the host. [0189] Embodiment 25: The host of the previous 2 embodiments, wherein: • the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and • the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application. [0190] Embodiment 26: A method implemented by a host operating in a communication system that further includes a network node and a user equipment (UE), the method comprising: • providing user data for the UE; and • initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the UE performs any of the operations of any of the Group A embodiments to receive the user data from the host. [0191] Embodiment 27: The method of the previous embodiment, further comprising: • at the host, executing a host application associated with a client application executing on the UE to receive the user data from the host application. [0192] Embodiment 28: The method of the previous embodiment, further comprising: • at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, • wherein the user data is provided by the client application in response to the input data from the host application. [0193] Embodiment 29: A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: • processing circuitry configured to provide user data; and • a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A embodiments to transmit the user data to the host. [0194] Embodiment 30: The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data from the UE to the host. [0195] Embodiment 31: The host of the previous 2 embodiments, wherein: • the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and • the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application. [0196] Embodiment 32: A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: • at the host, receiving user data transmitted to the host via the network node by the UE, wherein the UE performs any of the steps of any of the Group A embodiments to transmit the user data to the host. [0197] Embodiment 33: The method of the previous embodiment, further comprising: • at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE. [0198] Embodiment 34: The method of the previous 2 embodiments, further comprising: • at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, • wherein the user data is provided by the client application in response to the input data from the host application.

Claims

CLAIMS 1. A method performed by a User Equipment, UE, the method comprising: receiving (402), from a network node, configuration information for phase offsets feedback, where the configuration comprises a plurality of Channel State Information Reference Signal, CSI-RS, resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources; computing (412; 706b) phase offsets based on the plurality of CSI-RS resources received on the indicated antenna port of the UE; and reporting (414; 706c), to the network node, the computed phase offsets.

2. The method of claim 1, further comprising receiving (400) a configuration of one or more Sounding Reference Signals, SRS, resources, wherein each of the one or more SRS resources comprises one or more antenna ports.

3. The method of claim 2, wherein the CSI-RS resources are associated to one of the one or more SRS resources.

4. The method of claim 2 or 3, wherein the indication of an antenna port of the UE comprises information indicating an associated SRS resource out of the one or more SRS resources and information of an antenna port of the associated SRS resource.

5. The method of any of claims 2 to 4, wherein the indicated antenna port of the UE is a same antenna port for transmitting an associated SRS resource from the UE to the network.

6. The method of any of claims 2 to 5, wherein the one or more SRS resources are for antenna switching.

7. The method of any of claims 1 to 6, wherein each of the plurality of CSI-RS resources is associated to one of a plurality of Transmission and Reception Points, TRPs.

8. The method of any of claims 1 to 7, wherein computing phase offsets based on the plurality of CSI-RS resources comprises computing a phase difference between each of the plurality of CSI-RS resources and a reference CSI-RS resource, wherein the reference CSI-RS resource is one of the plurality of CSI-RS resources.

9. The method of any of claims 1 to 8, wherein reporting the computed phase offsets comprising reporting a computed phase offset for each of plurality of CSI-RS resources excluding the phase offset for a reference CSI-RS resource, wherein the phase offset for reference CSI-RS resource is zero.

10. The method of any of claims 1 to 9, further comprising receiving (402) a configuration for timing offsets feedback based on the plurality of reference signal resources, and computing (412) and reporting (414) a time difference between each of the plurality of CSI-RS resources and a reference CSI-RS resource, wherein the reference CSI-RS resource is one of the plurality of CSI-RS resources and the timing offset for reference CSI-RS resource is zero and is not reported.

11. The method of any of claims 1 to 10, wherein the CSI-RS resources are precoded based on channel information derived from the associated SRS resource at the network.

12. The method of any of claims 1 to 11, further comprising transmitting (404), at a first time instance, the associated SRS resource from the indicated antenna port of the UE.

13. The method of any of claims 1 to 12, wherein the configuration information for phase offsets feedback further comprises information indicating phase offsets feedback per subband.

14. The method of any of claims 1 to 12, wherein reporting (414) the phase offsets comprises reporting (414) the phase offsets computed per subband.

15. The method of any of claims 1 to 14, wherein the configuration information received from the network node further comprises information that configures the UE to receive each of the plurality of CSI-RS resources at a second time instance, wherein the second time instance occurs later than a first time instance at which the UE transmits Sounding Reference Signal, SRS.

16. A User Equipment, UE, adapted to: receive (402), from a network node, configuration information for phase offsets feedback, where the configuration comprises a plurality of Channel State Information Reference Signal, CSI-RS, resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources; compute (412; 706b) phase offsets based on the plurality of CSI-RS resources received on the indicated antenna port of the UE; and report (414; 706c), to the network node, the computed phase offsets.

17. The UE (1000) of claim 16, further adapted to perform the method of any of claims 2 to 15.

18. A User Equipment, UE, (1000), comprising: a communication interface (1012) comprising a transmitter (1018) and a receiver (1020); and processing circuitry (1002) associated with the communication interface (1012), the processing circuitry (1002) configured to cause the UE (1000) to: receive (402), from a network node, configuration information for phase offsets feedback, where the configuration comprises a plurality of Channel State Information Reference Signal, CSI-RS, resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources; compute (412; 706b) phase offsets based on the plurality of CSI-RS resources received on the indicated antenna port of the UE; and report (414; 706c), to the network node, the computed phase offsets.

19. The UE (1000) of claim 18, wherein the processing circuitry (1002) is further configured to cause the UE (1000) to perform the method of any of claims 2 to 15.

20. A method performed by a network node in a Radio Access Network, RAN, of a wireless communications system, the method comprising: transmitting (402) to a User Equipment, UE, configuration information for phase offsets feedback, where the configuration comprises a plurality of Channel State Information Reference Signal, CSI-RS, resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources; transmitting (410; 706a), on the indicated one of the plurality of antenna ports of the UE, a single port CSI-RS from each of a plurality of Transmission and Reception Points, TRPs, associated to the network node; and receiving (414; 706c), from the UE, a report of phase offsets for the plurality of TRPs.

21. The method of claim 20, further comprising transmitting (400), to the UE, a configuration of one or more Sounding Reference Signals, SRS, resources, wherein each of the one or more SRS resources comprises one or more antenna ports.

22. The method of claim 21, wherein the CSI-RS resources are associated to one of the one or more SRS resources.

23. The method of claim 21 or 22, wherein the indication of an antenna port of the UE comprises information indicating an associated SRS resource out of the one or more SRS resources and information of an antenna port of the associated SRS resource.

24. The method of any of claims 21 to 23, wherein the indicated antenna port of the UE is a same antenna port for transmitting an associated SRS resource from the UE to the network.

25. The method of any of claims 21 to 24, wherein the one or more SRS resources are for antenna switching.

26. The method of any of claims 20 to 25, wherein each of the plurality of CSI-RS resources is associated to one of a plurality of Transmission and Reception Points, TRPs.

27. The method of any of claims 20 to 26, wherein the phase offsets reflect a phase difference between each of the plurality of CSI-RS resources and a reference CSI-RS resource, wherein the reference CSI-RS resource is one of the plurality of CSI-RS resources.

28. The method of any of claims 20 to 27, wherein the phase offsets comprise a phase offset for each of the plurality of CSI-RS resources excluding a phase offset for a reference CSI-RS resource, wherein the phase offset for reference CSI-RS resource is zero.

29. The method of any of claims 20 to 28, further comprising transmitting (402), to the UE, a configuration for timing offsets feedback based on the plurality of reference signal resources, and receiving (414), from the UE, a report of a time difference between each of the plurality of CSI- RS resources and a reference CSI-RS resource, wherein the reference CSI-RS resource is one of the plurality of CSI-RS resources and the timing offset for reference CSI-RS resource is zero and is not reported.

30. The method of any of claims 20 to 29, wherein the CSI-RS resources are precoded using different precoders for the plurality of TRPs.

31. A network node for a Radio Access Network, RAN, of a wireless communications system, the network node adapted to: transmit (402) to a User Equipment, UE, configuration information for phase offsets feedback, where the configuration comprises a plurality of Channel State Information Reference Signal, CSI-RS, resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources; transmit (410; 706a), on the indicated one of the plurality of antenna ports of the UE, a single port CSI-RS from each of a plurality of Transmission and Reception Points, TRPs, associated to the network node; and receive (414; 706c), from the UE, a report of phase offsets for the plurality of TRPs.

32. The network node of claim 31, further adapted to perform the method of any of claims 21 to 30.

33. A network node for a Radio Access Network, RAN, of a wireless communications system, the network node comprising processing circuitry configured to cause the network node to: transmit (402) to a User Equipment, UE, configuration information for phase offsets feedback, where the configuration comprises a plurality of Channel State Information Reference Signal, CSI-RS, resources for channel measurement and an indication of an antenna port of the UE on which the UE is to receive the plurality of CSI-RS resources; transmit (410; 706a), on the indicated one of the plurality of antenna ports of the UE, a single port CSI-RS from each of a plurality of Transmission and Reception Points, TRPs, associated to the network node; and receive (414; 706c), from the UE, a report of phase offsets for the plurality of TRPs.

34. The network node of claim 33, wherein the processing circuitry is further configured to cause the network node to perform the method of any of claims 21 to 30.