Channel state information feedback for coherent joint transmission calibration
By measuring and reporting time, frequency, and phase offsets, the UE facilitates improved synchronization and communication performance in multi-TRP systems, addressing synchronization issues and enhancing throughput and reliability.
Patent Information
- Application Number
- PCT/CN2024/084901
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-03-29
- Publication Date
- 2025-10-02
AI Technical Summary
In wireless communication systems using multiple transmission and reception points (TRPs), the lack of synchronization and different propagation delays between TRPs cause channel mismatches, leading to performance degradation and user dissatisfaction due to time, frequency, and phase offsets.
The UE measures and reports time, frequency, and phase offsets associated with different TRPs, allowing the network entity to perform pre-compensation for improved synchronization, using configured CSI-RS resources and QCL properties.
This approach enhances signal synchronization and communication performance by accurately determining and compensating for offsets, improving throughput and reliability in coherent joint transmission.
Smart Images

Figure CN2024084901_02102025_PF_FP_ABST
Abstract
Description
CHANNEL STATE INFORMATION FEEDBACK FOR COHERENT JOINT TRANSMISSION CALIBRATIONTECHNICAL FIELD
[0001] Aspects of the present disclosure relate generally to wireless communication and techniques for calibrating channel state information feedback.BACKGROUND
[0002] The quality of service between a user equipment (UE) and a network entity (e.g., a base station) can be degraded by several factors, such as loss in signal strength, bandwidth limitations, interfering signals, and so forth. This is particularly true for UEs operating at a cell edge, which is frequently impacted by weak signal quality. One solution to address service degradation is to utilize multiple transmission and reception points (TRPs) for communicating with a UE. In a multi-TRP environment, a network entity such as a base station may have multiple TRPs, for example, macro-cells, small cells, pico-cells, femto-cells, remote radio heads, relay nodes, etc. located at different geographic locations within a cell. A network entity such as a base station coordinates joint scheduling, transmission, and reception for the multiple TRPs when communicating with a UE. The use of multiple TRPs may improve reliability, coverage, and capacity. For example, a UE at a cell edge may be served by multiple TRPs for improved signal transmission and reception resulting in increased throughput for the UE. The joint scheduling and transmission of signals from a network entity via multiple TRPs may be referred to as “coherent joint transmission” (CJT) .
[0003] BRIEF SUMMARY
[0004] The systems, methods, and devices of this disclosure each have several innovative aspects, no single one of which is solely responsible for the desirable attributes disclosed herein.
[0005] One innovative aspect of the subject matter described in this disclosure can be implemented as a method for wireless communications by a user equipment (UE) . The method may include receiving, from a network entity, at least one channel state information (CSI) report configuration that configures the UE to report at least one of a time offset (TO) , a frequency offset (FO) , or a phase offset (PO) associated with one or more CSI reference signal (CSI-RS) resources. The method may further include receiving, from the network entity, the one or more CSI-RS resources. The method may further include transmitting, to the network entity, at least one CSI report indicating the at least one of the TO, FO, or PO for the one or more CSI-RS resources based on a reference CSI-RS resource.
[0006] Another innovative aspect of the subject matter described in this disclosure can be implemented as a method for wireless communications by a network entity. The method may include transmitting, to a UE, at least one CSI report configuration that configures the UE to report at least one of a TO, an FO, or a PO associated with one or more CSI reference signal (CSI-RS) resources. The method may further include transmitting, to the UE, the one or more CSI-RS resources. The method may further include receiving, from the UE, at least one CSI report indicating the at least one of the TO, FO, or PO for the one or more CSI-RS resources based on a reference CSI-RS resource.
[0007] Another innovative aspect of the subject matter described in this disclosure can be implemented as an apparatus or system. In some implementations, an apparatus includes a communication unit and a processing system. The processing system is configured to control the communication unit to implement any one of the methods described in this document.
[0008] Details of one or more implementations of the subject matter described in this disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, the drawings, and the claims.BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Note that the relative dimensions of the following figures may not be drawn to scale. Like reference numbers and designations in the various drawings indicate like elements. To easily identify the discussion of any particular element or act, the most significant digit or digits in a reference number refer to the figure number in which that element is first introduced.
[0010] FIG. 1 is a diagram illustrating an example wireless system including a user equipment communicating with a network entity via multiple transmit / receive points using coherent joint transmission.
[0011] FIG. 2 is a sequence diagram illustrating example operations of a communications process for providing channel state information feedback with time offset (TO) , frequency offset (FO) , and / or phase offset (PO) information.
[0012] FIG. 3 is a block diagram illustrating a first example channel state information (CSI) measurement configuration.
[0013] FIG. 4A is a block diagram illustrating a first example CSI report based on a report subset restriction.
[0014] FIG. 4B is a block diagram illustrating a second example CSI report based on a report subset restriction.
[0015] FIG. 5 is a timing diagram illustrating an example of reporting time offset, frequency offset, and / or phase offset based on CSI reference signals (CSI-RSs) and a timing restriction.
[0016] FIG. 6 is a block diagram illustrating a second example CSI measurement configuration.
[0017] FIG. 7 is a timing diagram illustrating an example of reporting time offset, frequency offset, and / or phase offset based on CSI reference signals and discontinuous reception (DRX) or discontinuous transmission (DTX) status.
[0018] FIG. 8A is a block diagram illustrating an example CSI report including a CSI part 1 and a CSI part 2.
[0019] FIG. 8B is a block diagram illustrating a first example of further details of the CSI part 2.
[0020] FIG. 8C is a block diagram illustrating a second example of further details of the CSI part 2.
[0021] FIG. 9 is a timing diagram illustrating an example quasi-co-location (QCL) consistency period or window configuration based on the TO and / or FO pre-compensation.
[0022] FIG. 10 is a graph illustrating a comparison of an example of CSI-RS measurement based on a pre-compensated time offset and CSI-RS measurement without a pre-compensated time offset.
[0023] FIG. 11 is a timing diagram illustrating an example transmission configuration indicator (TCI) update for a UE-specific tracking reference signal (TRS) and physical downlink shared channel (PDSCH) .
[0024] FIG. 12 is a flow chart diagram illustrating example operations of a method for a user equipment to provide channel state information feedback including time offsets, frequency offsets, and / or phase offsets.
[0025] FIG. 13 is a flow chart diagram illustrating example operations of a method for a network entity to receive channel state information feedback including time offsets, frequency offsets, and / or phase offsets.
[0026] FIG. 14 is a block diagram illustrating example configurations of a network entity and a user equipment.DETAILED DESCRIPTION
[0027] The following description is directed to certain implementations for the purpose of describing the innovative aspects of this disclosure. However, a person having ordinary skill in the art will readily recognize that the teachings herein can be applied in a multitude of different ways. Some of the examples in this disclosure are based on wireless communication according to the 3rd Generation Partnership Project (3GPP) wireless standards, such as the 4th generation (4G) Long Term Evolution (LTE) , 5th generation (5G) New Radio (NR) , and 6th generation (6G) standards. However, the described implementations can be implemented in any device, system, or network that is capable of transmitting and receiving radio frequency signals according to any of the wireless communication standards, including any of the Institute of Electrical and Electronics Engineers (IEEE) 802.11, 802.15, or 802.16 wireless standards, or other known signals that are used to communicate within a wireless, cellular, or internet of things (IOT) network, such as a system utilizing 3G, 4G, 5G, WiFi or future radio technology.
[0028] As described above, some wireless communication systems use coherent joint transmission (CJT) in multiple transmission and reception point (TRP) operation to improve signal quality for signals communicated between a network entity and a user equipment (UE) , thereby improving communication efficiency and throughput. A problem that may occur in multiple TRP operation is that the TRPs may be located at different distances and directions from the UE. For example, the UE may receive signals from multiple TRPs, each at a different distance and different direction from the UE. This may result in different Doppler shifts associated with each signal received by the UE from the different TRPs. Additionally, the TRPs may not be fully synchronized with one another, may be at different distances from the UE, and / or may have different propagation delays associated with each signal received by the UE from the different TRPs. The lack of full synchronization between TRPs and / or the different propagation delays may result in different time offsets, frequency offsets, or phase offsets for signals transmitted and received by the different TRPs with respect to the UE. This lack of synchronization may cause channel mismatches for channel state information (CSI) measurement, which may lead to performance degradation and user dissatisfaction.
[0029] Various aspects of this disclosure relate to techniques for a UE to determine time offsets, frequency offsets, and phase offsets associated with different TRPs. In some aspects, the network entity may configure one or more channel state information reference signal (CSI-RS) resources for the UE to report time, frequency, and / or phase offset measurement. In some aspects, different CSI-RS resources are configured for reporting a time offset (TO) , frequency offset (FO) , and phase offset (PO) . In other aspects, the same CSI-RS resource is configured for reporting the TO, FO, and / or PO. Additionally, the configuration information can indicate which offsets are to be reported, and / or how many offsets to be reported. Based on the configuration, the UE measures a TO, FO, and / or PO for the TRPs using the configured reference signal (s) . In some aspects, a first TRP is selected as the reference TRP. That is, a CSI-RS resource associated with the first TRP may be selected or configured as a reference CSI-RS resource. Accordingly, the UE determines one or more TOs, FOs, and / or POs for the other TRPs with respect to the reference TRP. The UE reports, based on the configuration and the CSI-RS measurements, the TO, FO, and / or PO to the network entity.
[0030] The network entity can perform pre-compensation of offsets for subsequent transmissions based on the UE-reported TO, FO, and / or PO. For example, the network entity calculates pre-compensated signal transmission offsets (such as timing, frequency, or phase offsets) that are applied to the subsequent transmissions based on the UE-reported TO, FO, and / or PO. The network entity uses the pre-compensated signal transmission offsets to transmit CSI-RS (s) for CJT CSI measurement.
[0031] The pre-compensated signal transmission offsets may be specific to a cell (cell-specific) or specific to a UE (UE-specific) . For cell-specific pre-compensation, the network entity may pre-compensate the signal transmission TO, signal transmission FO, and / or signal transmission PO for the TRPs without pre-compensation of a propagation delay offset. For UE-specific pre-compensation, the network entity may pre-compensate the signal transmission TO, signal transmission FO, and / or signal transmission PO for the TRPs with pre-compensation of propagation delay offset. In some aspects, it is also possible to perform the pre-compensation in a UE group-specific manner.
[0032] To facilitate the CSI measurement based on the CSI-RS, the network entity may configure the antenna port quasi-co-location (QCL) property for the CSI-RS. The network entity may configure the source reference signal for the QCL indication for the CSI-RS as follows:
[0033] · A CSI-RS for tracking configured for QCL-TypeA and QCL-TypeD indication.
[0034] · A CSI-RS for tracking configured for QCL-TypeA indication and a CSI-RS for beam management configured for QCL-TypeD indication; or
[0035] · A synchronization signal block (SSB) configured for QCL-TypeC and QCL-TypeD indication.
[0036] The QCL types and the measurements associated with the different QCL types are defined as follows:
[0037] · 'typeA' : Doppler shift, Doppler spread, average delay, and delay spread.
[0038] · 'typeB' : Doppler shift and Doppler spread.
[0039] · 'typeC' : Doppler shift, average delay.
[0040] · 'typeD' : Spatial Receiving (Rx) parameter.
[0041] Particular implementations of the subject matter described in this disclosure may be implemented to realize one or more potential advantages. For example, a UE can accurately determine the TO, FO, and / or PO for different TRPs used to communicate with a network entity. The use of the TO, FO, and / or PO by the network entity and the UE can improve the synchronization of signals communicated between the network entity and the UE when compared to existing systems. Therefore, this improved synchronization can facilitate improved performance when the UE receives the downlink signals from multiple TRPs for CJT operation.
[0042] FIG. 1 is a conceptual diagram illustrating an example wireless system including a user equipment communicating with a network entity via multiple transmit / receive points using coherent joint transmission. In the example shown in FIG. 1, wireless communication system 100 includes a UE 130 that wirelessly communicates with a network entity 120 via TRPs 122A-122D in a multi-TRP mode of operation. Although illustrated as a smartphone in FIG. 1, the UE 130 may be implemented as any suitable computing or electronic device, such as a mobile communication device, a modem, cellular phone, gaming device, navigation device, media device, laptop computer, desktop computer, tablet computer, smart appliance, vehicle-based communication system, an Internet-of-things (IoT) device (e.g., sensor node, controller / actuator node, combination thereof) , and the like. Network entity 120 (e.g., base station, an Evolved Universal Terrestrial Radio Access Network Node B (E-UTRAN Node B) , evolved Node B, eNodeB, eNB, Next Generation Node B, gNode B, gNB, ng-eNB, access point, radio head or the like) may be implemented in a macrocell, microcell, small cell, picocell, or the like, or any combination thereof. The network entity 120 may be configured to use MIMO communication in which multiple TRPs (such as TRPs 122A-122D) associated with the network entity 120 are used to exchange wireless communication signals with UE 130.
[0043] In some aspects, the functionality, and thus the hardware components, of the network entity 120 may be distributed across multiple network nodes or devices and may be distributed in a manner to perform the functions described herein. As one example, the functionality of network entity 120 may be distributed across a radio unit (RU) , distributed unit (DU) , or central unit (CU) .
[0044] The UE 130 may communicate with network entity 120 and TRPs 122A-122D using wireless links (not shown in FIG. 1) , which may be implemented as any suitable type of wireless link. The wireless links may include one or more wireless links (e.g., radio links) or bearers implemented using any suitable communication protocol or standard, or combination of communication protocols or standards, such as 3GPP LTE, 5G NR, and so forth. Multiple wireless links may be aggregated in a carrier aggregation to provide a higher data rate for the UE 130.
[0045] The network entity 120 and TRPs 122A-122D support wireless communication with one or more UEs, such as UE 130, via radio frequency (RF) signaling using one or more applicable radio access technologies (RATs) as specified by one or more communications protocols or standards. The network entity 120 and the TRPs 122A-122D may employ any of a variety of RATs, such as operating as a NodeB (or base transceiver station (BTS) ) for a Universal Mobile Telecommunications System (UMTS) RAT (also known as “3G” ) , operating as an enhanced NodeB ( “eNB” ) for a 3GPP LTE RAT, operating as a 5G node B ( “gNB” ) for a 3GPP 5G NR RAT, and the like.
[0046] The network entity 120 and TRPs 122A-122D may be part of a radio access network (RAN) , for example, an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) , 5G NR RAN, or NR RAN. The network entity 120 may be connected to a core network 150. For example, the network entity 120 may connect to the core network 150 through an NG2 interface for control-plane signaling and using an NG3 interface for user-plane data communications when connecting to a 5G core network or using an Si interface for control-plane signaling and user-plane data communications when connecting to an Evolved Packet Core (EPC) network. The network entity 120 may communicate using an Xn Application Protocol (XnAP) through an Xn interface or using an X2 Application Protocol (X2AP) through an X2 interface to exchange user-plane and control-plane data. The UE 130 may connect, via the core network 150, to one or more wide area networks (WANs) 160 or other packet data networks (PDNs) , such as the Internet.
[0047] Network entity 120 may be coupled to TRPs via fronthaul networks. Fronthaul networks 132A and 132B are shown in FIG. 1 coupling network entity 120 to TRPs 122C and 122D respectively. Similarly, fronthaul networks may couple network entity 120 to other TRPs, for example, TRP 122A and 122B. As an example, fronthaul networks 132A and 132B may be high performance networks such as fiber optic networks.
[0048] Communications between network entity 120 and UE 130 utilize an uplink (UL) transmission path 112 for RF transmissions from the UE 130 to the network entity 120 and a downlink (DL) transmission path 114 for RF transmissions from the network entity 120 to the UE 130. As such, in the context of the UL transmission path 112, the UE 130 serves as the data sending device and the network entity 120 serves as the data receiving device, whereas in the context of the DL transmission path 114, the network entity 120 serves as the data sending device and the UE 130 serves as the data receiving device. UL transmission path 112 and DL transmission path 114 may utilize multiple communications channels for signal transmission. The multiple channels may each have different purposes.
[0049] UL transmission path 112 may include a Physical Uplink Shared Channel (PUSCH) , a Physical Uplink Control Channel (PUCCH) , and a Physical Random Access Channel (PRACH) . The PUSCH is used for the transmission of user data, such as voice data, video data, or text message data from UE 130 to network entity 120. Additionally, the PUSCH may be used to transmit control information (e.g., uplink control information (UCI) ) . The PUSCH may be shared by multiple UEs. The PUCCH is used for transmitting control information (e.g., UCI) from the UE 130 to the network, such as channel quality feedback, scheduling requests, and acknowledgments. The PRACH is used for random access in the uplink direction, enabling the UE 130 to access the system.
[0050] DL transmission path 114 may include one or more of a Physical Downlink Shared Channel (PDSCH) , a Physical Downlink Control Channel (PDCCH) , a Physical Broadcast Channel (PBCH) , or a paging channel. The PDSCH is used for transmission of user data from the network entity to the UE 130. The PDSCH may be shared by multiple UEs. As with the PUSCH, the data may be any type of information, such as voice data, video data, or text message data. The paging channel is used to notify the UE 130 that there is incoming traffic for it from the network entity 120.
[0051] UE 130 and network entity 120 may use channel state information (CSI) to optimize the quality of communications between the UE 130 and network entity 120 or a TRP. The network entity 120 may provide a CSI report configuration to the UE 130 for use in reporting the CSI to the network entity 120. For a CSI report, the UE 130 may report at least one of rank indicator (RI) , precoder matrix indicator (PMI) , channel quality indicator (CQI) , and layer indicator (LI) . RI and PMI may be used to indicate the digital precoder, CQI may be used to indicate the signal-to-interference plus noise (SINR) status in order to assist the network entity 120 to determine the modulation and coding scheme (MCS) , and LI may be used to identify the strongest layer for the reported precoder indicated by RI and PMI.
[0052] The network entity 120 may configure the UE 130 to measure and report the CSI for coherent joint transmission (CJT) from multiple TRPs (e.g., TRPs 122A-122D) . The network entity 120 may configure the UE 130 to measure and report the CSI based on a list of CSI reference signal (CSI-RS) resources. The network entity 120 transmits CSI-RS on the CSI-RS resources from the different TRPs 122A-122D as shown in FIG. 1. The UE 130 may analyze the CSI-RS for each TRP and calculate the various CSI parameters based on the analysis. The UE 130 may report the CSIs for each TRP to the network entity 120, which may use the reported CSIs to adjust various signal transmission parameters to attempt to optimize the communication between each TRP 122A-122D and UE 130.
[0053] In coherent joint transmission, the UE 130 receives downlink signals from multiple TRPs (e.g., TRPs 122A and 122B) with antenna combining. As an example, assume that R TRPs are used for CJT of downlink signals. At a downlink subcarrier k symbol l of a physical downlink shared channel (PDSCH) , the received signal Yk in the frequency domain can be obtained as follows: Yk, l=Hk, lWkXk, l+Nk, l (1)
[0054] where indicates the channel between the TRP j and the UE 130; is the digital precoder from TRP j; Xk, l is the modulated symbol before precoding; Nk, l is the noise plus interference. and T indicates the transpose of the matrix.
[0055] The locations of TRPs 124 used for transmissions to the UE 130 can affect various characteristics of the signals received by the UE 130 from the TRPs. For instance, in the example shown in FIG. 1, the distance 124A between UE 130 and TRP 122A is less than the distance 124B between UE 130 and TRP 122B. As a result, wireless communications signals communicated between UE 130 and TRP 122A will take less time to travel than signals communicated between UE 130 and TRP 122B. In other words, the propagation delay between the UE 130 and the TRP 122A may be different (e.g., shorter) than the propagation delay between the UE 130 and the TRP 122B. Similarly, propagation delays associated with signals transmitted from TRPs 122C and 122D may be different from each other and from TRPs 122A and 122B. Additionally, as shown in the example of FIG. 1, UE 130 may receive a signal from the TRPs 122A -122D at different angles from one another. In other words, the angle-of-arrival (AoA) of signals received from each of the TRPs 122A -122D may be different from one another.
[0056] Even though fronthaul networks connecting the TRPs 122A -122D to network entity 120 (for example, fronthaul networks 132A and 132B) may be high performance networks, there may be differences in the time it takes for control signals and / or data signals to reach different TRPs from network entity 120. This may result in TRPs 122A -122D not being fully synchronized with respect to communications between the network entity 120 and the UE 130 via TRPs 122A -122D. The possibility that the TRPs may not be fully synchronized and the existence of different propagation delays between different TRPs and the UE 130 may result in different time offsets, frequency offsets, and phase offsets for signals from different TRPs.
[0057] With regard to time offset (TO) , frequency offset (FO) and uplink / downlink phase offset (PO) , the network entity 120 can calculate an estimated channel for precoding as follows: PO (x, y) =exp {j (θy-θx) } (7)
[0058] Where fx indicates the carrier frequency for TRP x; S indicates the subcarrier spacing; θx indicates the uplink and downlink phase offset for TRP x; τx is the time offset between UE 130 and TRP x including the propagation delay and the time offset compared to a reference timing; and tl is the time for symbol l. As an example, if all the TRPs are well synchronized, the time offsets for each TRP compared to a reference timing is the same.
[0059] A problem with current systems is that the time offset, frequency offset, and phase offset with respect to signals arriving from different TRPs during CJT may cause channel mismatch for CSI measurement and PDSCH reception. This channel mismatch may lead to a degradation in communication performance between a UE 130 and a network entity. A technique to address this lack of synchronization is for the network entity 120 to compensate for the time offsets, frequency offsets and phase offsets of different TRPs (e.g., TRPs 122A -122D) prior to transmission of a signal. Such compensation may be referred to as pre-compensation. The network entity 120 may be configured to transmit CSI-RSs from each TRP with pre-compensated time, frequency, and phase offsets. However, a technical problem with such pre-compensation relates to calibrating the TOs, FOs, and POs so that the TRPs are well synchronized, e.g., the time offset for each TRP compared to a reference timing is substantially the same. An additional technical problem relates to configuring the UE 130 to report TOs, FOs, and POs to a network entity 120 in a CSI report instance for use in pre-compensating signals transmitted to the UE 130 from different TRPs (e.g., TRPs 122A -122D) .
[0060] One potential technical advantage of the techniques of the disclosure is that the UE can accurately determine the TO, FO, and / or PO for different TRPs used to communicate with a network entity. The use of the TO, FO, and / or PO by the network entity and the UE can improve the synchronization of signals communicated between the network entity and the UE when compared to existing systems. Therefore, this improved synchronization can facilitate improved performance when the UE receives the downlink signals from multiple TRPs for CJT operation.
[0061] In some aspects, the UE 130 may transmit UE capability information 170 to the network entity 120. The UE capability information may indicate whether or not the UE supports measuring and reporting TOs, FO, and / or POs for CJT operation. Depending on whether or not the UE supports measuring and reporting TOs, FOs, and / or POs, the network entity 120 may transmit a CSI measurement configuration 172 configuring the UE 130 for measuring and reporting TOs, FOs, and POs based on CSI-RSs received from TRPs 122. The UE 130 may receive the CSI-RSs from the TRPs 122 and measure TOs, FOs, and POs in accordance with the CSI measurement configuration 172. The UE 130 may report the measured TOs, FOs, and / or POs to the network entity 120. The network entity 120 may utilize the reported TOs, FOs, and / or POs to generate pre-compensated signals 176.
[0062] In the example shown in FIG. 1, four TRPs 122A-122D are illustrated. However, a wireless communications system may have more than four TRPs or less than four TRPs. Further details of various techniques and aspects of disclosure are provided below with respect to FIGs. 2-13.
[0063] FIGs. 2-13 describe various techniques for time offset and frequency offset measurement and reporting. In some examples that follow, the operations may be described as utilizing RRC signaling. Unless specified otherwise, RRC signaling may indicate a RRC reconfiguration message from the network entity to the UE 130, or a system information block (SIB) , where the SIB may be an existing SIB (e.g., SIB1) or a new SIB (e.g., SIB J, where J is an integer above 21) transmitted by the network entity.
[0064] FIG. 2 is a sequence diagram illustrating example operations of a communications process 200 for providing channel state information feedback with one or more of time offset, frequency offset, or phase offset data determined by a UE 130. Although not illustrated for the sake of illustration clarity, various acknowledgements for messages illustrated in FIG. 2 may be implemented to ensure reliable operations for measuring time and / or frequency offsets and providing CSI feedback.
[0065] At operation 202, the UE 130 may optionally transmit or report to network entity 120 UE capability information regarding the UE’s capability or support for measuring and / or reporting one or more of time offset (TO) , frequency offset (FO) , or phase offset (PO) in CSI feedback. In some aspects, UE 130 may communicate UE capability information to the network entity 120 during an initial communication session setup process between the UE 130 and the network entity 120. The UE capability information may include supported frequency bands, radio access technologies, maximum transmission power, maximum data rates, and network protocols. In some implementations, the UE 130 may report UE capability information indicating whether the UE 130 supports TO, FO, and / or PO measurement and reporting; whether the UE 130 supports a joint TO, FO, and / or PO report; a supported maximum number of CSI-RS resources or CSI-RS resource sets in a CSI report for reporting TO, FO, and / or PO; a supported maximum number of configured CSI-RS resources or CSI-RS resource sets across CSI reports for reporting TO, FO, and / or PO on a per bandwidth part, per component carrier (CC) or per band basis; a supported maximum number of CSI-RS resources or CSI-RS resource sets in a slot across CSI reports for reporting TO, FO, and / or PO on a per bandwidth part, per CC or per band basis; a supported time-domain behavior for the TO, FO, and / or PO report; a supported time-domain behavior for the CSI-RS for TO, FO, and / or PO report; a supported maximum number of CSI reports for reporting TO, FO, and / or PO on a per bandwidth part, per CC, or per band.
[0066] In the example of FIG. 2, the UE 130 transmits UE capability information to the network entity 120. In some implementations, the network entity 120 may receive the UE capability information from a core network (e.g., from an access and mobility management function (AMF) of the core network 150 of FIG. 1) . In some other implementations, the network entity 120 may receive the UE capability information from another network entity (e.g., a gNB or eNB) .
[0067] At operation 204, the network entity 120 may, depending on the UE capability information received at operation 202, configure at least one CSI report configuration for CSI feedback. Based on the UE capability information, the network entity 120 may configure one or more CSI report configurations for reporting one or more of TO, FO, or PO. Additionally, the network entity 120 may configure one or more lists of CSI-RS resources or CSI-RS resource sets (which may be referred to as “channel measurement resources” (CMR) ) for use by the UE 130 to measure characteristics of one or more channels. In some aspects, the network entity 120 may transmit the one or more CSI report configurations via Radio Resource Control (RRC) signaling, e.g., RRCReconfiguration.
[0068] In some aspects, the network entity 120 may configure the UE 130 with separate CSI report configurations, e.g., CSI-ReportConfig, for reporting TO, FO, and PO separately. Thus, the network entity 120 may configure a first CSI report configuration for TO report, a second CSI report configuration for FO report and a third CSI report configuration for PO report. In one example, the network entity 120 may configure the report quantity, e.g., reportQuantity, as timeOffset, frequencyOffset or phaseOffset for TO, FO or PO report respectively.
[0069] FIG. 3 is a block diagram illustrating a first example channel state information (CSI) measurement configuration. In the example shown in FIG. 3, a CSI measurement configuration 300 includes CSI report configuration 352, CSI report configuration 354, and CSI report configuration 356. Although three CSI report configurations are shown in the example provided in FIG. 3, a CSI measurement configuration 300 may have more or fewer CSI report configurations.
[0070] A CSI report configuration (e.g., CSI report configuration 352, CSI report configuration 354, and CSI report configuration 356) may specify various parameters with respect to TO, FO, and / or PO reporting. In some aspects, a CSI report configuration may specify channel measurement resources (CMRs) to be used by the UE 130 to calculate TO, FO, and / or PO. The CMRs may be a list of CSI-RS resources or CSI-RS resource sets. In some aspects, the CSI report configuration may specify a report quantity. The report quantity may indicate whether the CSI report configuration is for a TO, FO, or PO. In some aspects, the CSI report configuration may specify a quantity of reported TOs, FOs, or POs. The number of reported TOs, FOs, or POs, may be a maximum number of reported TOs, FOs, or POs. In one example, the number of reported TOs, FOs, or POs is based on the number of CSI-RS resources or CSI-RS resource sets for channel measurement in the CSI report configuration minus 1.
[0071] Various aspects of the CMR parameter, the report quantity parameter, the number of reported TOs, FOs, or POs and other CSI report configuration parameters will now be described.
[0072] With respect to the CMR parameter, in some aspects, the network entity 120 may configure the UE 130 with a resource setting for a CSI report configuration (e.g., CSI report configuration 352, CSI report configuration 354, or CSI report configuration 356) . The resource setting may be used for specifying a CMR. In one example, the CMR is configured by resourcesForChannelMeasurement. In some aspects, the network entity 120 refrains from configuring interference measurement resource (IMR) in a CSI report configuration (e.g., CSI report configuration 352, CSI report configuration 354, and CSI report configuration 356) . Thus, in some aspects, the UE 130 should not expect the network entity 120 to configure an interference measurement resource (IMR) in a CSI report configuration.
[0073] The network entity 120 may configure the UE 130 with N CSI-RS resources or CSI-RS resource sets as the CMR in CSI report configuration 352, CSI report configuration 354, or CSI report configuration 356, where N is an integer above 1. In one example, if N is above 1, the CSI report configuration 352, CSI report configuration 354, and CSI report configuration 356 may have separate corresponding resource sets or settings.
[0074] The network entity 120 may configure the UE 130 with a bandwidth of each of the CSI-RS resources to be greater than or equal to a first threshold. In some examples, the first threshold may be predefined. For example, the first threshold may be defined to be an active bandwidth part (BWP) for the CSI-RS. In some other examples, the UE 130 may report the first threshold to the network entity 120, for example, via UE capability information. The first threshold may be common or separate for a report of one or more of the TO, FO, or PO.
[0075] The network entity 120 may configure the UE 130 with a total number of subcarriers or resource elements in a symbol of each of the CSI-RS resources to be greater than or equal to a second threshold. In some aspects, the second threshold may be predefined. For example, the second threshold may be defined to be 156 or a minimum (3B, 156) . In some other aspects, the UE 130 may report the second threshold, for example, via UE capability information. The second threshold may be common or separate for a report of one or more of the TO, FO, or PO.
[0076] The network entity 120 may configure the UE 130 with a number of subcarriers per RB of each of the CSI-RS resources to be greater than or equal to a third threshold. In some aspects, the third threshold may be predefined, e.g., 3 or 1. In some other aspects, the UE 130 may report the third threshold via UE capability. In some aspects, the third threshold may be common or separate for reporting one or more of the TO, FO, or PO. In some other aspect, the UE 130 may report common or separate UE capability information indicating the supported frequency domain density for the CSI-RS resources for reporting of one or more of the TO, FO, or PO.
[0077] In some aspects, the network entity 120 may configure the UE 130 for 1-port CSI-RS resources for a report of one or more of the TO, FO, or PO. In some other aspects, the network entity 120 may configure the UE 130 for CSI-RS resources with up to P ports, where P may be predefined, or reported via the UE capability information.
[0078] The network entity 120 may configure the UE 130 for periodic, semi-persistent or aperiodic CSI-RS resources for reporting one or more of the TO, FO, or PO. The network entity 120 may configure the UE 130 for a common time domain behavior for the CSI-RS resources for a CSI report configuration. The UE 130 may report UE capability information indicating a common or separate supported time-domain behavior for the CSI-RS resources for reporting one or more of the TO, FO, or PO.
[0079] The network entity 120 may configure the UE 130 with a CSI-RS resource set for tracking, i.e., a tracking reference signal (TRS) , as the CMR, where the network entity 120 may configure the parameter trs-Info for the CSI-RS resource set. In some aspects, the network entity 120 may refrain from configuring the UE 130 with a CSI report configuration with report quantity set to other than ‘none’ or ‘timeOffset’ or ‘frequencyOffset’ or ‘phaseOffset’ for aperiodic TRS. In such aspects, the UE 130 may not expect to be configured with a CSI-ReportConfig with the higher layer parameter reportQuantity set to a value other than ‘none’ or ‘timeOffset’ or ‘frequencyOffset’ or ‘phaseOffset’ for aperiodic non-zero power (NZP) CSI-RS resource set configured with trs-Info. In some aspects, the network entity 120 may refrain from configuring the UE 130 with a CSI report configuration for periodic TRS except for report quantity value set to ‘tdcp’ or ‘timeOffset’ or ‘frequencyOffset’ or ‘phaseOffset’ . In such aspects, the UE 130 may not expect to be configured with a CSI-ReportConfig for periodic NZP CSI-RS resource set configured with trs-Info, except for reportQuantity set to ‘tdcp’ or ‘timeOffset’ or ‘frequencyOffset’ or ‘phaseOffset’ .
[0080] With respect to a TO report, the network entity 120 may configure the UE 130 with information indicating whether the network entity 120 has performed FO pre-compensation for the CSI-RS resources configured as CMR. If the network entity 120 indicates that it has performed FO pre-compensation, the network entity 120 may configure the UE 130 such that the CSI-RS resources share a common QCL source reference signal for Doppler shift and / or Doppler spread indication. If the network entity 120 indicates that it has not performed FO pre-compensation, the network entity 120 may configure the UE 130 with separate QCL source reference signals for Doppler shift and / or Doppler spread indication for the CSI-RS resources.
[0081] With respect to an FO report, the network entity 120 may configure the UE 130 with information indicating whether the network entity has performed TO pre-compensation for the CSI-RS resources configured as CMR. If the network entity 120 has performed TO pre-compensation, the network entity 120 may configure the UE 130 such that the CSI-RS resources share a common QCL source reference signal for average delay and / or delay spread indication. If the network entity has not performed TO pre-compensation, the network entity 120 may configure the UE 130 with separate QCL source reference signals for average delay and / or delay spread indication for the CSI-RS resources.
[0082] With respect to a PO report, in some implementations, the network entity 120 may configure the UE 130 with information indicating whether the network entity has performed FO and / or TO pre-compensation for the CSI-RS resources configured as CMR. If the network entity 120 has performed FO pre-compensation, the network entity 120 may configure the UE 130 such that the CSI-RS resources share a common QCL source reference signal for Doppler shift and / or Doppler spread indication. If the network entity 120 has not performed FO pre-compensation, the network entity 120 may configure the UE 130 with separate QCL source reference signals for Doppler shift and / or Doppler spread indication for the CSI-RS resources. If the network entity 120 has performed TO pre-compensation, the network entity 120 may configure the UE 130 such that the CSI-RS resources share a common QCL source reference signal for average delay and / or delay spread indication. If the network entity 120 has not performed TO pre-compensation, the network entity 120 may configure the UE 130 with separate QCL source reference signals for average delay and / or delay spread indication for the CSI-RS resources.
[0083] In some other implementations, the network entity 120 may transmit the CSI-RS resources configured as CMR with FO and / or TO pre-compensation. In some aspects, the UE 130 may assume that there is no FO and / or TO for the CSI-RS resources configured as CMR for PO measurement and report. In some other aspects, the UE 130 may report the UE capability information indicating whether the UE supports the PO measurement and reporting without FO and / or TO pre-compensation for the CSI-RS resources configured as CMR.
[0084] In some aspects, the network entity 120 may configure the UE 130 such that the CSI-RS resources for channel measurement for TO, FO, and / or PO measurement based on the same QCL-TypeD property. Alternatively, the network entity 120 may refrain from configuring the QCL-TypeD for the CSI-RS resources for channel measurement for TO, FO, and / or PO measurement. In such aspects, the TO, FO, and / or PO report may be applicable for frequency range 1 (FR1) only. In some aspects, the UE 130 may expect the network entity 120 to configure the UE 130 with CSI-RS resources for channel measurement for TO, FO, and / or PO measurement based on the same QCL-TypeD property. In some other aspects, the UE 130 may not expect the network entity 120 to configure the QCL-TypeD property for the CSI-RS resources for channel measurement for TO, FO, and / or PO measurement.
[0085] With respect to the report quantity parameter, in some aspects, the network entity 120 may configure the UE 130 with a maximum number of reported TOs, FOs, or POs for a CSI report configuration. In the example shown in FIG. 3, the network entity 120 has configured the CSI report configuration 352, CSI report configuration 354, and CSI report configuration 356 for TO, FO, and PO reporting, respectively. In some aspects, the UE 130 may report the number of TOs, FOs, or POs in each report instance. In some other aspects, the network entity 120 may configure the UE 130 with a number of reported TOs, FOs, or POs, and the UE 130 may report the TOs, FOs, or POs based on the configured number of reported TOs, FOs, or POs. The UE 130 may report UE capability information indicating common or separate values for the supported maximum number of reported TOs, FOs, or POs.
[0086] The network entity 120 may configure the UE 130 with a TO, FO, and / or PO report subset restriction. The report subset restriction may indicate the CSI-RS resources or CSI-RS resource sets from N configured CSI-RS resources or CSI-RS resource sets associated with TO, FO, and / or PO report. As an example, the network entity 120 may configure the UE 130 with K CSI-RS resources or CSI-RS resource sets using the TO, FO, and / or PO report subset restriction. The UE 130 may report the TO, FO, and / or PO based on a subset of, or all of, the K CSI-RS resources or CSI-RS resource sets. In some aspects, the UE 130 may always report the TO, FO, and / or PO for the K CSI-RS resources or CSI-RS resource set as described with respect to FIG. 4A below. In some other aspects, the UE 130 may report the TO, FO, and / or PO for the CSI-RS resources or CSI-RS resource sets selected from the K CSI-RS resources or CSI-RS resource set, as described with respect to FIG. 4B below. The network entity 120 may configure the TO, FO, and / or PO report subset restriction by RRC signaling, MAC CE, or DCI. As an example, the network entity 120 may configure the UE 130 with a TO, FO, and / or PO report subset restriction via a MAC CE activating or deactivating the semi-persistent TO, FO, and / or PO report. As another example, the network entity 120 may configure the UE 130 with a TO, FO, and / or PO report subset restriction via an aperiodic CSI report triggering state in a DCI triggering the aperiodic TO, FO, and / or PO report.
[0087] FIGs. 4A and 4B illustrate example CSI reporting based on report subset restrictions. In the examples illustrated in FIGs. 4A and 4B, reference is made to a “CSI-RS resource. ” It is noted that the CSI-RS resource may be part of a CSI-RS resource set. In some aspects, the UE may measure one or move of TO, FO, and / or PO based on a CSI-RS resource set including multiple CSI-RS resources. Thus, in the description of FIGs. 4A and 4B, reference to a CSI-RS resource may also be considered a reference to a CSI-RS resource set.
[0088] FIG. 4A is a block diagram illustrating a first example CSI report based on a report subset restriction. In the example shown in FIG. 4A, a network entity (e.g., network entity 120) has configured a UE (e.g., UE 130) with four CSI resources, CSI-RS resource 404A through CSI-RS resource 404D. Additionally, the network entity 120 has configured a CSI-RS subset restriction comprising, in this example, a bitmap having values {0100} indicating that a TO, FO and / or PO for CSI-RS resource 404B is to be included in a TO, FO, and / or PO report. Further, network entity 120 has configured the number of reported TOs, FOs, and / or POs with a value of two (2) indicating that the UE 130 is to provide a maximum of two TOs, FOs, and / or POs in an offset report. In this example, UE 130 has selected CSI-RS resource 404A to be a reference CSI-RS resource for TO, FO, and / or PO reporting.
[0089] In this example, the UE 130 measures a TO, FO, and / or PO for CSI-RS resource 404B based on the CSI-RS subset restriction value of {0100} to generate a measured TO, FO, and / or PO 406A. The UE 130 is free to select another CSI-RS resource for reporting a measured TO, FO, and / or PO. In this example, the UE 130 has selected CSI-RS resource 404D to generate measured TO, FO, and / or PO 406B.
[0090] FIG. 4B is a block diagram illustrating a second example CSI report based on a report subset restriction. The example of FIG. 4B is similar to the example of FIG 4A, with the difference being that the network entity 120 has configured the UE 130 with a CSI-RS subset restriction value of {0110} indicating that TOs, FOs and / or POs for CSI-RS resource 404B and CSI-RS resource 404C are to be included in a TO, FO, and / or PO report. In the example of FIG. 4B, the UE is not free to select a CSI-RS resource for inclusion in a TO, FO, and / or PO report because the network entity 120 has specified two CSI-RS resources (e.g., CSI-RS resource 404B and CSI-RS resource 404C) and further, the network entity has configured a maximum of two CSI-RS resources for reporting TO, FO, and / or PO. Thus, in this example, the UE 130 generates measured TO, FO, and / or PO 406A associated with CSI-RS resource 404B and measured TO, FO, and / or PO 406C associated with CSI-RS resource 404C.
[0091] Returning to FIG. 3, further configuration aspects will be described. The network entity 120 may refrain from configuring the UE 130 with a CSI-Report sub-configuration list, e.g., csi-ReportSubConfigList for a CSI report configuration (e.g., any of CSI report configurations 352-354) . Refraining from configuring a CSI-Report sub-configuration list may reduce the overhead for the CSI report configuration. In some aspects, if the UE 130 is configured with a CSI-ReportConfig that contains a list of sub-configurations, for example, provided by csi-ReportSubConfigList, the UE 130 may not expect the higher layer parameter reportQuantity to be set to 'cri-RSRP' , 'cri-SINR' , 'cri-SINR-Index' , 'cri-RSRP-Index' , 'none' , 'ssb-Index-RSRP' , 'ssb-Index-SINR' , 'ssb-Index-RSRP-Index' , 'ssb-Index-SINR-Index' , 'tdcp' , ‘timeOffset’ , ‘frequencyOffset’ or ‘phaseOffset. ’ As one example, for a serving cell or cell group, the network entity 120 may refrain from configuring the UE 130 with configuration (s) for network energy saving and configuration (s) for reporting one of TO, FO and PO simultaneously. Similarly, for a serving cell or cell group, the UE 130 may not expect to receive, from the network entity 120, configuration (s) for network energy saving and configuration (s) for reporting one of TO, FO and PO simultaneously.
[0092] The network entity 120 may configure the UE 130 for a time-domain behavior, e.g., periodic, semi-persistent, or aperiodic reporting of the TO, FO, or PO in a CSI report configuration (e.g., any of CSI report configurations 352-354) . In some aspects, the network entity 120 may configure the UE 130 to provide a semi-persistent or aperiodic report of the TO, FO, or PO via PUSCH.
[0093] The network entity 120 may configure the UE 130 with a time restriction for channel measurement, e.g., timeRestrictionForChannelMeasurements, in the CSI report configuration (e.g., any of CSI report configurations 352-354) . In some aspects, if a time restriction for channel measurement is not configured, the UE 130 may derive the channel measurements for computing TO, FO, and / or PO values to be reported in an uplink slot n based on the NZP CSI-RS no later than receiving the CSI reference resource associated with the CSI resource setting. If a time restriction for channel measurement is configured, the UE 130 may derive the channel measurements for computing TO, FO, or PO values to be reported in uplink slot n based on a most recent occasion of NZP CSI-RS associated with the CSI resource setting that is received no later than the CSI reference resource.
[0094] In particular implementations, if the higher layer parameter timeRestrictionForChannelMeasurements in CSI-ReportConfig is set to "notConfigured" , the UE 130 shall derive the channel measurements for computing TO, FO, or PO value reported in uplink slot n based on only the NZP CSI-RS, no later than the CSI reference resource, associated with the CSI resource setting. If the higher layer parameter timeRestrictionForChannelMeasurements in CSI-ReportConfig is set to "Configured" , the UE 130 shall derive the channel measurements for computing TO, FO, or PO reported in uplink slot n based on only the most recent, no later than the CSI reference resource, occasion of NZP CSI-RS associated with the CSI resource setting.
[0095] FIG. 5 is a timing diagram illustrating an example of reporting time offset, frequency offset, and / or phase offset based on CSI reference signals (CSI-RSs) and a timing restriction. In the example of FIG. 5, the network entity 120 has configured the UE 130 with three CSI-RS resources, CSI-RS resource 518A, CSI-RS Resource 518B, and CSI-RS resource 518C for use in calculating TO, FO, and / or PO. Additionally, in this example, CSI-RS resource 518C is the reference resource.
[0096] In the example shown in FIG. 5, at time t1, the UE 130 receives CSI-RS Resource 518A. At time t2, the UE 130 receives CSI-RS Resource 518B. At time t3, the UE 130 again receives CSI-RS Resource 518A. At time t4, the UE 130 again receives CSI-RS Resource 518B. At time t5, the UE 130 may optionally receive the CSI-RS reference resource.
[0097] In this example, if the UE 130 is configured with a time restriction, the UE 130 may utilize the second instances of CSI-RS Resource 518A and CSI-RS Resource 518B for calculating a TO, FO, and / or PO for the TO / FO / PO report 532 transmitted by the UE 130 to the network entity 120 at time t6. In this case, the UE 130 is configured with a time restriction, and per the aspects described above, the UE 130 uses the most recent instances of the CSI-RS resources to calculate the TO, FO, and / or PO for reporting.
[0098] If the UE 130 is not configured with a time restriction, the UE 130 may utilize both the first and second instances of CSI-RS Resource 518A and CSI-RS Resource 518B for calculating a TO, FO, and / or PO for the TO / FO / PO report 532 transmitted by the UE 130 to the network entity 120 at time t6. In this case, the UE 130 is not configured with a time restriction, and per the aspects described above, the UE 130 may use any of the instances of the CSI-RS resources 518 received prior to the CSI-RS reference resource to calculate the TO, FO, and / or PO for reporting.
[0099] Returning to FIG. 3, in some aspects, the network entity 120 may refrain from configuring a time restriction for channel measurement in a CSI report configuration (e.g., any of CSI report configurations 352 -356) . For example, the network entity may refrain from configuring the parameter timeRestrictionForChannelMeasurements with value indicating “configured” or “notConfigured. ” In such aspects, the UE 130 may not expect the network entity 120 configure timeRestrictionForChannelMeasurements, as “configured” or “notConfigured” in the CSI report configuration. In some other aspects, the UE 130 may ignore the configuration of a time restriction for channel measurement in a CSI report configuration.
[0100] In some aspects, in the time domain, a CSI reference resource R for a CSI reporting for TO, FO, and / or PO in uplink slot n'may be defined by a single downlink slot by the formula:
[0101] where:
[0102] Koffset is a parameter configured by a higher layer as specified in clause 4.2 of 3GPP Technical Specification (TS) 38.213,
[0103] μKoffsetis the subcarrier spacing configuration for Koffset with a value of 0 for frequency range 1,
[0104] μDL and μUL are the subcarrier spacing configurations for DL and UL, respectively, and
[0105] μoffset is determined by a higher-layer configured ca-SlotOffset for the cells transmitting the uplink and downlink (e.g., as defined in clause 4.5 of 3GPP TS 38.211) .
[0106] With respect to periodic and semi-persistent CSI reporting, in some aspects, if a single CSI-RS / SSB resource is configured for channel measurement, nCSI_ref is the smallest value greater than or equal to such that the value corresponds to a valid downlink slot. In some aspects, if multiple CSI-RS / SSB resources are configured for channel measurement nCSI_ref is the smallest value greater than or equal to such that the value corresponds to a valid downlink slot.
[0107] With respect to aperiodic CSI reporting, if the network entity 120 provides DCI to the UE 130 indicating that the UE 130 is to report CSI in the same slot as the CSI request, then nCSI_ref is a value such that the reference resource is in the same valid downlink slot as the corresponding CSI request. If the network entity 120 does not provide DCI to the UE 130 indicating that the UE 130 is to report CSI in the same slot as the CSI request, then nCSI_ref is the smallest value greater than or equal to such that slot n-nCSI_ref corresponds to a valid downlink slot, where Z' corresponds to a minimum delay requirement for a TO, FO and / or PO report.
[0108] In some aspects, the network entity 120 and UE 130 may determine the value of Z’ based on at least one of the followings for a CSI report for TO, FO, or PO report:
[0109] ● The number of measured TOs, FOs, and / or POs (N)
[0110] ● The number of reported TOs, FOs, and / or POs (M)
[0111] ● The number of report quantity types (X)
[0112] ● Whether the CMR is transmitted based on TO / FO pre-compensation
[0113] As an example, in some aspects, the minimum delay for a TO, FO, and / or PO measurement may be predefined (e.g., Z1’ or Z2’ or Z3’ as defined in 3GPP TS 38.214 section 5.4) . In some other aspects, the delay for a TO, FO, and / or PO measurement may be reported by the UE 130 via UE capability information, which may be denoted as r. In such aspects, Z’ may be based on Nr or Mr or NXr or MXr. As another example, for a PO report, if the network entity 120 transmits CMR based on TO and / or FO pre-compensation, the network entity 120 and the UE 130 may determine the Z’ value based on a first value; otherwise, the network entity 120 and UE 130 may determine Z’ based on a second value. The first value and second value may be pre-defined or reported by via UE capability information. In one example, the first value is smaller than the second value. In another example, the first value may be a first Z’ corresponding to the case where TO and / or FO pre-compensation is performed for CMR, and the second value may be a second Z’ corresponding to the case where neither TO nor FO pre-compensation is performed.
[0114] In some aspects, the minimum delay (Z) between the last symbol of the PDCCH triggering an aperiodic TO, FO, and / or PO report and the first symbol of the PUSCH including the triggered aperiodic TO, FO, and / or PO report, may be determined as Z’ + q, where q may be pre-defined or reported by UE 130 via UE capability information.
[0115] In some aspects, the UE 130 may report outdated TO, FO, and / or PO or drop the CSI report for TO, FO, and / or PO report if the scheduling offset does not meet the Z or Z’ minimum delay requirement.
[0116] The network entity 120 and UE 130 may determine the number of CSI processing units (CPUs) required for a TO, FO, or PO report based on at least one of:
[0117] ● The number of measured TOs, FOs, and / or POs (N) .
[0118] ● The number of reported TOs, FOs, and / or POs (M) .
[0119] ● The number of report quantity types (X) .
[0120] ● Whether the CMR is transmitted based on TO and / or FO pre-compensation.
[0121] The UE 130 may report the outdated TOs, FOs, and / or POs or drop the CSI report for the TO, FO, and / or PO report if the generating the report would exceed a predetermined or configured maximum CPU count.
[0122] A first example of a CSI measurement configuration (i.e., CSI measurement configuration 300) that network entity 120 may provide to the UE 130 as part of operation 204 of FIG. 2 has been described above with respect to FIG. 3. A second example of a CSI measurement configuration will now be described.
[0123] FIG. 6 is a block diagram illustrating a second example CSI measurement configuration 602. In the example of FIG. 6, the network entity 120 may configure the UE 130 for a joint TO, FO, and / or PO report. As an example, the network entity 120 may configure the UE 130 to report of various combinations of TO, FO, and / or PO such as TO and / or FO, TO and / or PO, FO and / or PO, and TO, FO, and / or PO.
[0124] Like CSI measurement configuration 300 of FIG. 3, CSI measurement configuration 602 may include one or more CSI report configurations. In the example shown in FIG. 6, CSI measurement configuration 602 includes N CSI report configurations 604A -604N. CSI report configurations 604A -604N may specify various parameters with respect to TO, FO, and / or PO reporting. In some aspects, a CSI report configuration may specify channel measurement resources (CMRs) to be used by the UE 130 to calculate TO, FO, and / or PO. The CMRs may be a list of CSI-RS resources or CSI-RS resource sets. In some aspects, the CSI report configuration may specify a report quantity. The report quantity may indicate whether the CSI report configuration is for a TO, FO, and / or PO. As an example, the network entity 120 may configure the UE 130 with a report quantity (e.g., reportQuantity) having a value of timeOffset-frequencyOffset (indicating a TO and FO report) , timeOffset-phaseOffset (indicating TO and PO report) , frequencyOffset-phaseOffset (indicating a FO and PO report) or timeOffset-frequencyOffset-phaseOffset (indicating a TO, FO, and PO report) . In some aspects, the CSI report configuration may specify a number of reported TOs, FOs, and / or POs. The number of reported TOs, FOs, or POs, may be a maximum number of reported TOs, FOs, or POs. In one example, the number of reported TOs, FOs, and / or POs may be based on the number of CSI-RS resources or CSI-RS resource sets for channel measurement for TO, FO or PO respectively in the CSI report configuration minus 1.
[0125] Various aspects of the CMR parameter, the report quantity parameter, the number of reported TOs, FOs, or POs and other CSI report configuration parameters will now be described.
[0126] With respect to the CMR parameter, the network entity 120 may configure one or more resources in a resource setting in a CSI report configuration (e.g., CSI report configuration 604A-604N) . The one or more resources indicated in the resource setting may be used as a channel measurement resource (CMR) . In one example, the network entity 120 configures the CMR via a resourcesForChannelMeasurement parameter. In some aspects, the network entity 120 may refrain from configuring an interference measurement resource (IMR) in a CSI measurement configuration 602. In such aspects, the UE 130 may not expect the network entity 120 to configure interference measurement resources (IMRs) in the CSI measurement configuration 602.
[0127] In some aspects, the network entity 120 may configure CSI-RSs as CMR in a CSI report configuration (e.g., CSI report configuration 604A-604N) in a manner similar to that described above with respect to FIG. 3, with differences described below.
[0128] In some implementations, the network entity 120 may configure the UE 130 with a common CMR for measuring TO, FO, and / or PO. For example, in some aspects, the network entity 120 may configure a list of CMR including N CSI-RS resources or CSI-RS resource sets in a CSI report configuration, where N is an integer above 1. The UE 130 may measure the TO, FO, and / or PO based on the common CSI-RS resources or CSI-RS resource sets.
[0129] In some implementations, the network entity 120 may configure the UE 130 with separate CMR for measuring each of TO, FO, and / or PO. For example, in some aspects, the network entity 120 may configure X lists of CMRs, where a CMR list x includes Jx CSI-RS resources or CSI-RS resource sets in a CSI report configuration (e.g., CSI report configurations CSI report configuration 604A-604N) , where Jx is an integer above 1, and X equals the number of report quantities. In such aspects, the UE 130 may measure the TO based on the first list of CMR, FO based on the second list of CMR and PO based on the third list of CMR.
[0130] In some implementations, the network entity 120 may configure the UE 130 with common CMR for TO and / or FO, TO and / or PO, or FO and / or PO measurement and another CMR for measurement of TO, FO, or PO. For example, in some aspects, the network entity 120 may configure Y list of CMRs, where the CMR list y including Ny CSI-RS resources or CSI-RS resource sets in a CSI report configuration (e.g., CSI report configurations 604A-604N) , where Ny is an integer above 1, and Y may be smaller than the number of report quantities. The UE 130 may measure the TO and / or FO, TO and / or PO, or FO and / or PO based on the first list of CMR, and may measure PO, FO or TO respectively, based on the second list of CMR.
[0131] With respect to the report quantity parameter, in some implementations, the network entity 120 may configure the UE 130 with a restriction on the number of reported TOs, FOs, and / or POs. For example, in some aspects, the network entity 120 may configure the UE 130 with a maximum number of reported TOs, FOs, and / or POs, where the maximum number may be specified to be applied separately or commonly to the reported TOs, FOs, and / or POs. The UE 130 may report the number of TOs, FOs, and / or POs in each report instance, up to the specified maximum number. In some other aspects, the network entity 120 may configure the UE 130 with a number of reported TOs, FOs, and / or POs separately or commonly, and the UE 130 may report the TO, FO, and / or PO based on the configured number of reported TOs, FOs, and / or POs. In some aspects, the UE 130 may report whether or not the UE supports a common or separate number of TOs, FOs, and / or POs via UE capability information. The UE 130 may also report the supported maximum number of reported TOs, FOs, and / or POs.
[0132] In some implementations, the network entity 120 may configure a TO, FO, and / or PO report subset restriction. The support subset restriction may indicate the CSI-RS resources or CSI-RS resource sets from N configured CSI-RS resources or CSI-RS resource sets that are to be included in a TO, FO, and / or PO report. As an example, the network entity 120 may configure the UE 130 with K CSI-RS resources or CSI-RS resource sets using the TO, FO, and / or PO report subset restriction. The UE 130 may report the TO, FO, and / or PO based on a subset of, or all of, the K CSI-RS resources or CSI-RS resource sets. In some aspects, the network entity 120 may configure the report subset restriction by RRC signaling or MAC CE or DCI. In one example, the network entity 120 may configure the UE 130 with a report subset restriction via a MAC CE activating or deactivating a semi-persistent TO, FO, and / or PO report. In another example, the network entity 120 may configure the UE 130 with a report subset restriction via an aperiodic CSI report triggering state in a DCI triggering the aperiodic TTO, FO, and / or PO report.
[0133] Similar to CSI measurement configuration 300 described above, the network entity 120 may refrain from configuring the UE 130 with a CSI-Report sub-configuration list, e.g., csi-ReportSubConfigList for a CSI report configuration (e.g., any of CSI report configurations 604A-604N) . Refraining from configuring a CSI-Report sub-configuration list may reduce the overhead for the CSI report configuration. In some aspects, if the UE 130 is configured with a CSI-ReportConfig that contains a list of sub-configurations, for example, provided by csi-ReportSubConfigList, the UE 130 may not expect the higher layer parameter reportQuantity to be set to 'cri-RSRP' , 'cri-SINR' , 'cri-SINR-Index' , 'cri-RSRP-Index' , 'none' , 'ssb-Index-RSRP' , 'ssb-Index-SINR' , 'ssb-Index-RSRP-Index' , 'ssb-Index-SINR-Index' , 'tdcp' , ‘timeOffset’ , ‘frequencyOffset, ’ ‘phaseOffset, ’ ‘timeOffset-frequencyOffset’ , ‘frequencyOffset-phaseOffset’ , ‘timeOffset-phaseOffset’ , or ‘timeOffset-frequencyOffset-phaseOffset. ’ As one example, for a serving cell or cell group, the network entity 120 may refrain from configuring the UE 130 with configuration (s) for network energy saving and configuration (s) for reporting one of TO, FO and PO simultaneously. Similarly, for a serving cell or cell group, the UE 130 may not expect to receive, from the network entity 120, configuration (s) for network energy saving and configuration (s) for reporting one of TO, FO and PO simultaneously.
[0134] The network entity 120 may configure the UE 130 for a time-domain behavior, for example, periodic, semi-persistent, or aperiodic reporting of the TO, FO, or PO in a CSI report configuration (e.g., any of CSI report configurations 604A-604N) . In some aspects, the network entity 120 may configure the UE 130 to provide a semi-persistent or aperiodic report of the TO, FO, or PO via a PUSCH.
[0135] The network entity 120 may configure the UE 130 with a time restriction for channel measurement, e.g., timeRestrictionForChannelMeasurements, in the CSI report configuration (e.g., any of CSI report configurations 604A-604N) . In some aspects, if a time restriction for channel measurement is not configured, the UE 130 may derive the channel measurements for computing TO, FO, and / or PO values to be reported in an uplink slot n based on the NZP CSI-RS no later than receiving the CSI reference resource associated with the CSI resource setting. If a time restriction for channel measurement is configured, the UE 130 may derive the channel measurements for computing TO, FO, or PO values to be reported in uplink slot n based on a most recent occasion of NZP CSI-RS associated with the CSI resource setting that is received no later than the CSI reference resource. In some aspects, the CSI reference resource can be calculated as described in formula (8) above.
[0136] In particular implementations, if the higher layer parameter timeRestrictionForChannelMeasurements in CSI-ReportConfig is set to "notConfigured" , the UE 130 shall derive the channel measurements for computing a TO, FO, and / or PO value reported in uplink slot n based on only the NZP CSI-RS, no later than the CSI reference resource, associated with the CSI resource setting. If the higher layer parameter timeRestrictionForChannelMeasurements in CSI-ReportConfig is set to "Configured" , the UE 130 shall derive the channel measurements for computing TO, FO, and / or PO reported in uplink slot n based on only the most recent, no later than the CSI reference resource, occasion of NZP CSI-RS associated with the CSI resource setting.
[0137] In some implementations, the network entity 120 may refrain from configuring the UE 130 with a time restriction for channel measurement. For example, the network entity 120 may refrain from configuring the timeRestrictionForChannelMeasurements parameter, as “configured” or “notConfigured” in a CSI report configuration. In such implementations, the UE 130 may not expect the network entity 120 configure timeRestrictionForChannelMeasurements, as “configured” or “notConfigured” in the CSI report configuration. In some other implementations, the UE 130 may ignore the configuration of the time restriction for channel measurement in the fourth CSI report configuration for TO, FO, and / or PO measurement.
[0138] Returning to FIG. 2, at operation 206, the network entity 120 may optionally transmit the configured measurement resources to the UE 130. In some aspects, the network entity 120 may transmit the configured CMRs as a Medium Access Control (MAC) Control Element (CE) . In some other aspects, the network entity 120 may transmit the CMRs as part of Downlink Control Information (DCI) .
[0139] At operation 208, the network entity 120 optionally triggers the UE 130 to provide a CSI report including TO, FO, and / or PO in accordance with the CSI report configuration received at operation 202. In some aspects, the MAC CE or DCI transmitted at operation 206 may trigger the UE 130 to report the TO, FO, and / or PO based on the configured CSI report configuration (s) for a TO, FO, and / or PO report.
[0140] At operation 210, responsive to the trigger received at operation 208, the UE 130 measures one or more of the TO, FO, and / or PO in accordance with the CSI report configuration received at operation 202. In some aspects, receiving a MAC CE or DCI that includes CMRs for TO, FO, and / or PO measurement may trigger the UE 130 to measure the TO, FO, and / or PO.
[0141] In some aspects, the UE 130 may be configured with multiple antenna ports. The UE 130 may measure the TO, FO, and / or PO on a per antenna port basis. In some aspects, The UE 130 may report the number of receiver branches, i.e., antenna ports, for the TO, FO, and / or PO measurement and report via UE capability information. In some other aspects, the UE 130 may report the number of receiver branches in the TO, FO, and / or PO report. In some other aspects, the network entity 120 may configure the number of receiver branches for the TO, FO, and / or PO report.
[0142] In some aspects, the network entity 120 and the UE 130 may be configured for cell discontinuous transmission (DTX) . When the network entity 120 and the UE 130 are configured for cell DTX, the UE 130 may not receive a CSI-RS and semi-persistent CSI-RS configured as the CMR for TO, FO, and / or PO report during the non-active periods of the cell DTX. For example, when the network entity 120 and the UE 130 are configured for cell DTX, during the non-active periods of the cell DTX the UE 130 may not receive a periodic CSI-RS or semi-persistent CSI-RS that is configured as the CMR for a TO, FO, and / or PO report. During the non-active periods of cell DTX, the UE 130 may not be expected to receive the periodic CSI-RS and semi-persistent CSI-RS configured in CSI report configuration in CSI-ReportConfig for CSI reporting. associated with the higher layer parameter reportQuantity comprising at least ‘RI’ or ‘timeOffset’ or ‘frequencyOffset’ or ‘phaseOffset’ .
[0143] In some aspects, the network entity 120 may configured the UE 130 with a CSI report configuration in CSI-ReportConfig associated with a higher layer parameter reportQuantity having a value of at least one of ‘RI, ’ ‘timeOffset, ’ ‘frequencyOffset, ’ or ‘phaseOffset. ’ In such aspects, a UE 130 configured with cell DTX may provide a CSI report when the UE 130 receives, during active periods of cell DTX and no later than the CSI reference resource, at least one CSI-RS transmission occasion for each periodic CSI-RS resource or semi-persistent CSI-RS resource for channel measurement and / or interference measurement. In some other aspects, a UE 130 configured with cell DTX may drop (e.g., omit or refrain from transmitting) a CSI report when the UE 130 fails to receive, during active periods of cell DTX, or receives later than the CSI reference resource, at least one CSI-RS transmission occasion for each periodic CSI-RS resource or semi-persistent CSI-RS resource for channel measurement and / or interference measurement.
[0144] In some aspects, if the network entity 120 does not configure the UE 130 with a time restriction for channel measurements, the UE 130 may derive the channel measurements for computing a TO, FO, and / or PO value to be reported. For example, when cell DTX is activated, the UE 130 may derive the channel measurements based on an NZP CSI-RS associated with a CSI resource setting that is received no later than the CSI reference resource and during the cell DTX active time. In some other aspects, if the network entity 120 configures the UE 130 with a time restriction for channel measurements, when cell DTX is activated, the UE 130 may derive the channel measurements for computing TO, FO, and / or PO based on a most recent occasion of NZP CSI-RS associated with the CSI resource setting that is received no later than the CSI reference resource during cell DTX active time.
[0145] In some particular implementations, if the higher layer parameter timeRestrictionForChannelMeasurements in CSI-ReportConfig is set to "notConfigured" , the UE 130 shall derive the channel measurements for computing TO, FO, and / or PO value reported in uplink slot n based on only the NZP CSI-RS, no later than the CSI reference resource, in cell DTX active time if cell DTX is activated, associated with the CSI resource setting. If the higher layer parameter timeRestrictionForChannelMeasurements in CSI-ReportConfig is set to "Configured" , the UE 130 shall derive the channel measurements for computing TO, FO, and / or PO reported in uplink slot n based on only the most recent, no later than the CSI reference resource, in cell DTX active time if cell DTX is activated, occasion of NZP CSI-RS associated with the CSI resource setting.
[0146] In some aspects, when the network entity 120 configures the UE 130 for cell DTX, the UE 130 may still receive periodic CSI-RSs and semi-persistent CSI-RSs that may be configured as the CMR TO, FO, and / or PO report during the non-active periods of the cell DTX. UE may report one or more TOs, FOs, and / or POs depending on various criteria, for example, Z and / or Z’ , CPU counts, and the like.
[0147] In some aspects, after certain events such as CSI report (re) configuration, serving cell activation, BWP change, or activation of semi-persistent CSI (SP-CSI) and the like, the UE 130 may provide a CSI report including TO, FO, and / or PO. For example, the UE 130 may provide the CSI report after receiving at least one CSI-RS transmission occasion of each CSI-RS resource for channel measurement no later than the CSI reference resource and within the discontinuous reception (DRX) active time, when DRX is configured. If the UE 130 does not receive at least one CSI-RS transmission occasion of each CSI-RS resource for channel measurement, or receives the CSI-RS transmission after the CSI reference resource, or receives the CSI-RS transmission outside of the DRX active time, the UE 130 may drop (e.g., omit or refrain from transmitting) a TO, FO, and / or PO report.
[0148] In some particular implementations, after the CSI report (re) configuration, serving cell activation, BWP change, or activation of SP-CSI, the UE 130 reports a CSI report for TO, FO, and / or PO report, e.g., with reportQuantity including ‘timeOffset’ , ‘frequencyOffset’ , ‘phaseOffset’ , ‘timeOffset-frequencyOffset’ , ‘frequencyOffset-phaseOffset’ , ‘timeOffset-phaseOffset’ , or ‘timeOffset-frequencyOffset-phaseOffset, only after receiving at least one CSI-RS transmission occasion of each CSI-RS resource for channel measurement no later than CSI reference resource and within the discontinuous reception (DRX) active time, when DRX is configured, and drops the report otherwise.
[0149] FIG. 7 is a timing diagram illustrating an example of reporting time offset, frequency offset, and / or phase offset based on CSI reference signals and discontinuous reception (DRX) or discontinuous transmission (DTX) status. Like the example of FIG. 5, in the example of FIG. 7, the network entity 120 has configured the UE 130 with three CSI-RS resources, CSI-RS resource 518A, CSI-RS Resource 518B, and CSI-RS resource 518C for use in calculating TO, FO, and / or PO. Additionally, in this example, the CSI-RS resource 518C is the reference resource.
[0150] In the example shown in FIG. 7, at time t1, the UE 130 receives CSI-RS Resource 518A during a DRX active time or a cell DTX active period. A DRX inactive time begins at time t2 and runs at least to time t5. At time t2, the UE 130 may (or may not) receive CSI-RS Resource 518B. At time t3, the UE 130 may (or may not) receive CSI-RS Resource 518A. At time t4, the UE 130 may (or may not) receive CSI-RS Resource 518B. At time t5, the UE 130 may (or may not) receive the CSI-RS reference resource 518C. In the example shown, only one CSI-RS resource, CSI-RS resource 518A is received during a DRX active time or DTX active period. Because the other CSI-RS resources are either received during a DRX inactive time or DTX non-active period, or not received at all, the UE 130 may not use them for measuring TOs, FOs, or POs. As a result, the UE 130 does not transmit a CSI report 532 including TOs, FOs, and / or POs.
[0151] Returning to FIG. 2, at operation 212, the UE 130 may transmit the CSI report including one or more of the TO, FO, or PO to the network entity 120. In some aspects, the UE 130 may transmit the TO, FO, and / or PO report by physical uplink shared channel (PUSCH) or physical uplink control channel (PUCCH) .
[0152] In some aspects, the UE 130 may report the TO for a CSI-RS resource or CSI-RS resource set based on the UE 130 comparing the TO for the CSI-RS resource or CSI-RS resource set to a TO for a reference CSI-RS resource or CSI-RS resource set, for example, by calculating a difference between the two TOs. Similarly, the UE 130 may report the FO for a CSI-RS resource or CSI-RS resource set based on the FO compared to the FO for the reference CSI-RS resource or CSI-RS resource set. Likewise, the UE 130 may report the PO for a CSI-RS resource or CSI-RS resource set based on the PO compared to PO of the reference CSI-RS resource or CSI-RS resource set.
[0153] In some aspects, the reference CSI-RS resource or CSI-RS resource set may be pre-defined. In some other aspects, the reference CSI-RS resource or CSI-RS resource set may be configured by the network entity 120. In still other aspects, the reference CSI-RS resource or CSI-RS resource set may be reported by the UE 130.
[0154] As described above, in some aspects, the UE 130 may be configured with multiple antenna ports. In some aspects, the UE 130 may report the measured TO, FO, and / or PO for each antenna port. In some other aspects, the UE 130 may report the minimum, maximum or average value of TO, FO, and / or PO across the TOs, FOs, and / or POs per UE 130 antenna port. As an example, if the UE 130 is configured to use receiver diversity, the reported TO, FO, and / or PO value may not be lower than the corresponding TO, FO, and / or PO of any of the individual receiver branches. As another example, if the UE 130 is configured to use receiver diversity, the reported TO, FO, and / or PO value may not be higher than the corresponding TO, FO, and / or PO of any of the individual receiver branches. As a further example, if the UE 130 is configured to use receiver diversity, the reported TO, FO, and / or PO value may not be lower than the corresponding TO, FO, and / or PO of any of the individual receiver branches and may not be higher than the corresponding TO, FO, and / or PO of any of the individual receiver branches.
[0155] In particular implementations, if receiver diversity is in use by the UE, the reported TO / FO / PO value shall not be lower than the corresponding TO / FO / PO of any of the individual receiver branches. Alternatively, if receiver diversity is in use by the UE, the reported TO / FO / PO value shall not be higher than the corresponding TO / FO / PO of any of the individual receiver branches. Alternatively, if receiver diversity is in use by the UE, the reported TO / FO / PO value shall not be lower than the minimum and no higher than the maximum measured values across the receiver branches.
[0156] In some aspects, if a UE 130 reports TO, FO, and / or PO jointly in a CSI report, the UE 130 may report the TO, FO, and / or PO based on a common reference CSI-RS resource or CSI-RS resource set for some or all of TO, FO, and PO. In some other aspects, the UE 130 may report the TO, FO, and / or PO based on separate reference CSI-RS resources or CSI-RS resource sets for each of the TO, FO, and / or PO.
[0157] FIG. 8A is a block diagram illustrating an example CSI report included in a CSI part 1 and a CSI part 2. The UE 130 may report the TO 822, FO 824, and / or PO 826 via a PUSCH. As an example, in some aspects, the UE 130 may report the TO 822, FO 824, and / or PO 826 by CSI part 1 830 in the PUSCH. As another example, the UE 130 may report, in CSI part 1 830 in the PUSCH, the reference CSI-RS resource or CSI-RS resource set index within the configured CSI-RS resources or CSI-RS resource sets, and TO 822, FO 824 and / or PO 826 for CSI-RS resources or CSI-RS resource sets other than the reference CSI-RS resource or CSI-RS resource set. The UE may multiplex the TO 822, FO 824 and / or PO 824 based on the order of the CSI-RS resource or CSI-RS resource set index. In some other aspects, the UE 130 may report part of the TO, FO, and / or PO report in CSI part 1 830 and the remaining part of the TO, FO, and / or PO report in CSI part 2 820. As one example, the UE 130 may report, in CSI part 1 830, the number of reported TOs, FOs, and / or POs, the CSI-RS resource index (es) or CSI-RS resource set index (es) including or excluding the reference CSI-RS resource or CSI-RS resource set for the TO 822, FO 824, and / or PO 826. The UE 130 may report, in CSI part 2 820, the TO, FO, and / or PO for each CSI-RS resource or CSI-RS resource set indicated by the CSI-RS resource index (es) or CSI-RS resource set index (es) reported in CSI part 1 830. In some aspects, the UE 130 may exclude the TO, FO, and / or PO for the reference CSI-RS resource or CSI-RS resource set from CSI part 2 820.
[0158] When the total payload size of the CSI part 2 820 for the TO, FO, and / or PO report exceeds a maximum payload size for CSI part 2 on the PUSCH scheduled by the network entity 120, the UE 130 may omit part of the CSI part 2 820. The UE 130 may omit TO 822, FO 824, and / or PO 826 portions based on the priority for each portion. The UE 130 may determine one or multiple portions within a priority group. In some aspects, the UE 130 may determine the priority and the report portion for a priority group for a CSI report for TO, FO, and / or PO report based on the index of the CSI-RS resource or CSI-RS resource set corresponding to the TO, FO, and / or PO, e.g., the priority of a lower index is higher than or lower than that of a higher index.
[0159] FIG. 8B is a block diagram illustrating a first example of further details of the CSI part 2 where priority is based on a CSI-RS index. In the example of FIG. 8B, the priority of a portion is based on the index of the CSI-RS for which TO, FO, and / or PO is being reported. In this example, the TO, FO, and / or PO report for the CSI-RSs having indexes numbered from 1 to N exceeds the maximum payload size of CSI part 2. In this case, the UE 130 may omit lower priority groupings from the CSI part 2. In this example, the UE 130 has included CSI-RS 1 reported TO 822A-822N-1, CSI-RS 1 reported FO 824A-824N-1, and CSI-RS 1 reported PO 826A-826N-1 in the CSI part 2. Further, in this example, the CSI-RS resources may be grouped by the CSI-RS index (e.g., 1 - (N-1) ) for the respective TOs, FOs, and POs associated with the CSI-RS resources. Inclusion of CSI-RS N reported TO 822N, CSI-RS N reported FO 824N, and CSI-RS N reported PO 826N would cause the report TOs, FOs, and POs, to exceed the maximum CIS part 2 payload, and are therefore omitted from CSI part 2 in this example.
[0160] In some aspects, the UE 130 may determine the priority and the report portion for a priority group for a CSI report for TO, FO, and / or PO report based on the report content, e.g., the priority order for different report content may be different. For example, the priority of TO may be higher than the priority of FO, which in turn may be higher than the priority of PO. This example priority order may be different in different implementations.
[0161] FIG. 8C is a block diagram illustrating a second example of further details of the CSI part 2 where priority is based on report content. In the example of FIG. 8C, the priority of a portion is based on the content of the report. In the example shown in FIG. 8C, the priority of TO is higher than the priority of FO, which in turn is higher than the priority of PO.Like the example of FIG. 8B, in this example, the TO, FO, and / or PO report for the CSI-RSs having indexes numbered from 1 to N exceeds the maximum payload size of CSI part 2. In this case, the UE 130 may omit lower priority groupings from the CSI part 2. In this example, the UE 130 has included CSI-RSs reported TOs 822A-822N in a first group and CSI-RS reported FOs 824A-824N in a second group. Inclusion of CSI-RS reported POs 822A-822N would cause the reported TOs, FOs, and POs, to exceed the maximum CSI part 2 payload, and are therefore omitted from CSI part 2 in this example.
[0162] Returning to FIG. 2, at operation 214, the network entity 120 calculates one or more of a pre-compensation signal transmission TO, FO, or PO based on one or more of the TO, FO or PO reported by the UE 130 at operation 212. The network entity 120 may perform pre-compensation of TO, FO, and / or PO to transmit the CSI-RS for CJT CSI measurement and / or PDSCH based on CJT.
[0163] In some aspects, the network entity 120 may perform the pre-compensation of TO, FO, and / or PO in a cell-specific manner for CJT. For the cell-specific manner, the network entity 120 may pre-compensate the TO, FO, and / or PO for the TRPs without pre-compensation of a propagation delay offset. The network entity 120 may configure a TRS as the QCL source reference signal for PDCCH and PDSCH the UE 130 is configured for QCL-TypeA and / or QCL-TypeD indication. After applying a new TO pre-compensation, the network entity 120 may notify the UE 130 that the average delay and / or delay spread for a TRS may be updated. In one example, the notification from the network entity 120 may be an aperiodic triggering for the TRS measurement. The UE 130 may measure the average delay and / or delay spread for the TRS configured in the TCI state for PDCCH and PDSCH after the update time or the notification is effective and / or applied. Similarly, after applying a new FO pre-compensation, the network entity 120 may notify the UE 130 that the Doppler spread and / or Doppler shift for a TRS may be updated.
[0164] The network entity 120 may configure a QCL consistency period (also referred to as a QCL consistency window) for the TRS. The UE 130 may assume the QCL parameter or measured channel property for the TRS within a QCL consistency period may be the same. The network entity 120 may configure the starting time and / or duration for the QCL consistency period.
[0165] In some aspects, the network entity 120 may update the TO and / or FO pre-compensation periodically. In such aspects, the network entity 120 may configure the periodicity for the QCL consistency period to match the periodicity of the TO and / or FO update period.
[0166] In some other aspects, the network entity 120 updates the TO and / or FO pre-compensation aperiodically. In such aspects, the network entity 120 may configure the start of the QCL consistency period aperiodically and maintain the QCL consistency period until receiving another configuration of the start of a new QCL consistency period.
[0167] The UE 130 may assume the QCL parameters or measured channel properties may remain the same for the TRS during the QCL consistency period. The network entity 120 may configure the QCL parameters to be consistent in a QCL consistency period. The network entity 120 may transmit the configuration of the QCL consistency period by RRC signaling, MAC CE or DCI.
[0168] In some aspects, the network entity 120 may transmit the configuration in a UE-dedicated manner, e.g., based on cell radio network temporary identifier (C-RNTI) . In some other aspects, the network entity 120 may transmit the QCL consistency configuration or in group-cast manner, for example, based on an RNTI configured by the network entity 120 or a pre-defined RNTI.
[0169] FIG. 9 is a timing diagram 900 illustrating an example QCL consistency period or window configuration based on the TO and / or FO pre-compensation. In the example of FIG. 9, the network entity 120 has configured the UE 130 with a TRS 922. At time t1, the UE 130 receives a first instance of the TRS, TRS 922A. The TRS 922A is received during a first QCL consistency period that ends at t2, and thus, the UE 130 may assume that the QCL parameters for the TRS are the same as when the first QCL consistency period began. At time t2, the UE 130 receives a TO and / or FO pre-compensation factor update 924A. Receipt of the pre-compensation factor update 924A marks the end of the first QCL consistency period and the start of a second QCL consistency period. At times t3 and t4, the UE 130 receives second and third instances of the configured TRS, TRSs 922B and 922C, respectively. The UE 130 may assume that the QCL parameters for the 922B and 922C are as determined using the updated TO and / or FO pre-compensation factor 924A received at time t2. In other words, the QCL parameters are the same as when the second QCL consistency period began. At time t5, the UE 130 receives a second TO and / or FO pre-compensation factor update 924B. Receipt of the TO and / or FO pre-compensation factor update 924B marks the end of the second QCL consistency period and the beginning of a new QCL consistency period in which the UE 130 assumes that the QCL parameters updated based on the pre-compensation factor update 924B will remain the same for the duration of the new QCL consistency period.
[0170] In some other aspects, the UE 130 may perform the pre-compensation of TO, FO, and / or PO in a UE-specific manner for CJT. For the UE-specific manner, the network entity 120 may pre-compensate the TO, FO, and / or PO for the TRPs with pre-compensation of propagation delay offset.
[0171] In some aspects, the network entity 120 may perform a UE-specific TO, FO, and / or PO pre-compensation for CJT transmission for PDSCH only. The network entity 120 may configure a TRS as the QCL source reference signal for PDCCH and PDSCH for QCL-TypeA and / or QCL-TypeD indication. The network entity 120 may transmit the TRS without UE 130-specific TO / FO pre-compensation and transmit the PDSCH with UE 130-specific TO / FO pre-compensation.
[0172] In some aspects, the network entity 120 may configure or indicate the pre-compensated TO and / or FO for the PDSCH to the UE 130. The network entity 120 may transmit the configuration or indication by RRC, MAC CE or DCI. The UE 130 may measure the average delay, delay spread, Doppler spread and / or Doppler shift based on the TRS configured in the TCI state and the configured or indicated pre-compensated TO and / or FO for the PDSCH.
[0173] In some other aspects, the network entity 120 may perform the TO and / or FO pre-compensation based on the most recent TO and / or FO reported by the UE 130. The UE 130 may determine the average delay, delay spread, Doppler spread and / or Doppler shift based on the TRS configured in the TCI state and the reported TO and / or FO for the PDSCH.
[0174] FIG. 10 is a graph 1000 illustrating a comparison of an example of CSI-RS measurement based on a pre-compensated time offset 1044 and CSI-RS measurement without a pre-compensated time offset. In the graph 1000, the amplitude varies over time. Dashed line 1042 shows the amplitude over time of a channel as measured based on the TRS. Solid line 1040 shows the amplitude over time of the same channel with TO pre-compensation applied to the TRS. As can be seen in the graph 1000, the pre-compensated TO shifts the amplitude to the right of the graph 1000.
[0175] In some aspects, the network entity 120 may perform a UE-specific TO, FO, and / or PO pre-compensation for CJT transmission for PDSCH and TRS. The network entity 120 may configure the TRS as the QCL source reference signal for PDCCH and PDSCH for QCL-TypeA and / or QCL-TypeD indication. The network entity 120 may transmit the TRS and PDSCH with UE-specific TO / FO pre-compensation. In such aspects, the network entity 120 may not share the TRS with other UEs so that the TRS is specific to the UE 130.
[0176] In some aspects the network entity 120 may configure a limited number of periodic TRSs for a UE 130. As an example, the network entity may configure one TRS for the UE 130 and update the TCI state for the TRS dynamically. This may provide a technical advantage of reducing the latency and overhead associated with the TRS. The network entity 120 may update the TCI state for the periodic TRS by MAC CE or DCI. The MAC CE or DCI to update the TCI state for the periodic TRS may be separate from the TCI update signaling for PDSCH. The network entity 120 may indicate at least one of the following in the MAC CE or DCI:
[0177] ● Serving cell index indicating the serving cell where the periodic TRS is configured or transmitted.
[0178] ● BWP index indicating the BWP where the periodic TRS is configured or transmitted.
[0179] ● TCI state ID indicating the target TCI state to be applied to the periodic TRS.
[0180] ● Periodic TRS resource or resource set ID indicating the target periodic TRS to be applied with the indicated TCI state.
[0181] In some other aspects, the network entity 120 may configure the UE 130 such that the periodic TRS shares or follows the indicated TCI state for PDSCH, for example, a UE dedicated PDSCH. In some examples, the network entity 120 may configure in the TCI state a first and / or second QCL source reference signal for PDSCH and a third and / or fourth QCL source reference signal for the periodic TRS. In some other examples, the network entity 120 may only configure in the TCI state a first and / or second QCL source reference signal for the periodic TRS. Additionally, the network entity 120 and UE 130 may determine that the PDSCH or PDCCH to be applied with the TCI state is always QCLed with the TRS that shares or follows the indicated TCI state for PDSCH.
[0182] In some aspects, for example, as an extension of the UE dedicated PDSCH described above, the network entity 120 may configure the UE 130 such that some other types of CSI-RS share or follow the indicated TCI state for PDSCH, e.g., UE dedicated PDSCH. In some examples, the network entity 120 may configure in the TCI state a first and / or second QCL source reference signal for PDSCH and a third and / or fourth QCL source reference signal for the CSI-RS. In some other examples, the network entity 120 may configure in the TCI state a first and / or second QCL source reference signal for the PDSCH based on the corresponding QCL type. The UE 130 may determine the QCL parameters for the CSI-RS based on a subset of, or all of, the QCL parameters for a source reference signal for a QCL type. In one example, the network entity 120 may configure the UE 130 such that the aperiodic CSI-RS for CSI acquisition (e.g., without trs-Info and repetition configured) shares or follows the indicated TCI state for PDSCH, and the network entity 120 may configure the UE 130 with one QCL source reference signal in the TCI state as a TRS for QCL-TypeA indication. The UE 130 may assume that the aperiodic CSI-RS for CSI acquisition is QCLed with the TRS based on a subset of QCL parameters from the QCL-TypeA, e.g., QCL-TypeB.
[0183] FIG. 11 is a timing diagram illustrating an example transmission configuration indicator (TCI) update for a UE-specific tracking reference signal (TRS) and a UE dedicated physical downlink shared channel (PDSCH) . In the example of FIG. 11, the network entity 120 has configured the UE 130 with a TRS 922 and has configured a PDSCH 1126. At time t1, the UE 130 receives a transmission via PDSCH 1126A. At time t2, the UE 130 receives a first instance of the TRS, TRS 922A. The PDSCH 1126A and the TRS 922A are based on a first TCI state. At time t3, the UE 130 receives a TCI update for the TRS 922 and PDSCH 1126 that indicates a second TCI state (perhaps different from the first TCI state) . At time t4-t7, the UE 130 receives second and third instances of the configured TRS, TRSs 922B and 922C and second and third instances of the PDSCH 1126B and 1126C. The UE 130 may assume that the QCL parameters for the 922B and 922C are as determined using the updated TO and / or FO pre-compensation factor 924A received at time t2. At times t4-t7, the TRSs 922B and 922C, and PDSCHs 1126B and 1126C are based on the second TCI state 1128 received at time t3.
[0184] In some aspects, the UE 130 may perform the pre-compensation of TO, FO, and / or PO in a group-specific manner. The network entity 120 may apply a common TO, FO, and / or PO pre-compensation factor for UEs in a group. In some aspects, the UEs in a group may be based on similar propagation delay or other.
[0185] Returning to FIG. 2, at operation 216, the network entity 120 transmits, to the UE 130, a configuration of QCL consistency for the tracking reference signal (TRS) , pre-compensated TO, FO, and / or PO for PDSCH and / or TCI update for the periodic TRS and PDSCH.
[0186] At operation 218, the network entity 120 and the UE 130 may communicate based on the configured QCL consistency period for TRS, pre-compensated transmission signal TO, FO and / or PO, and / or TCI state for periodic TRS and PDSCH.
[0187] FIG. 12 is a flow chart diagram illustrating example operations of a method for a user equipment to provide channel state information feedback including time offsets, frequency offsets, and / or phase offsets. The example operations of method 1200 may be performed, for example, by UE 130 of FIG. 1, FIG. 2, and FIG. 14.
[0188] At block 1202, and as described above with respect to FIG. 2, operation 202, the UE may optionally transmit or report to the network entity UE capability information regarding the UE’s capability or support for measuring and / or reporting one or more of time offset, frequency offset, or phase offset in CSI feedback. In some aspects, the UE may communicate UE capability information to the network entity during an initial communication session setup process between the UE and the network entity. The UE capability information may include supported frequency bands, radio access technologies, maximum transmission power, maximum data rates, and network protocols. In some implementations, the UE may report UE capability information indicating whether the UE supports TO, FO, and / or PO measurement and reporting; whether the UE supports a joint TO, FO, and / or PO report; a supported maximum number of CSI-RS resources or CSI-RS resource sets in a CSI report for reporting TO, FO, and / or PO; a supported maximum number of configured CSI-RS resources or CSI-RS resource sets across CSI reports for reporting TO, FO, and / or PO on a per bandwidth part, per component carrier (CC) or per band basis; a supported maximum number of CSI-RS resources or CSI-RS resource sets in a slot across CSI reports for reporting TO, FO, and / or PO on a per bandwidth part, per CC or per band basis; a supported time-domain behavior for the TO, FO, and / or PO report; a supported time-domain behavior for the CSI-RS for TO, FO, and / or PO report; a supported maximum number of CSI reports for reporting TO, FO, and / or PO on a per bandwidth part, per CC, or per band.
[0189] At block 1204, and as described above with respect to FIG. 2, operation 204, the UE may receive, from the network entity, control signaling to configure at least one CSI report configuration for CSI feedback. Based on the UE capability information, the network entity may configure one or more CSI report configurations for reporting one or more of TO, FO, or PO. Additionally, the network entity may configure one or more lists of CSI-RS resources or CSI-RS resource sets (which may be referred to as “channel measurement resources” (CMR) ) for use by the UE to measure characteristics of one or more channels.
[0190] At block 1206, and as described above with respect to FIG. 2, operation 206, the UE may optionally receive the configured measurement resources to the UE. In some aspects, the network entity may transmit the configured CMRs as a Medium Access Control (MAC) Control Element (CE) . In some other aspects, the network entity may transmit the CMRs as part of Downlink Control Information (DCI) .
[0191] At block 1208, and as described above with respect to FIG. 2, operation 208, the UE may optionally receive control signaling that triggers the UE to provide a CSI report including TO, FO, and / or PO in accordance with the CSI report configuration received at block 1202. In some aspects, the MAC CE or DCI received at block 1206 may trigger the UE to report the TO, FO, and / or PO based on the configured CSI report configuration (s) for a TO, FO, and / or PO report.
[0192] At block 1210, and as described above with respect to FIG. 2, operation 210, the UE may measure one or more of the TO, FO, and / or PO in accordance with the CSI report configuration received at block 1202. In some aspects, receiving a MAC CE or DCI that includes CMRs for TO, FO, and / or PO measurement may trigger the UE to measure the TO, FO, and / or PO.
[0193] At block 1212, and as described above with respect to FIG. 2, operation 212, the UE may transmit the CSI report including one or more of the TO, FO, or PO to the network entity. In some aspects, the UE may transmit the TO, FO, and / or PO report by physical uplink shared channel (PUSCH) or physical uplink control channel (PUCCH) .
[0194] At block 1216, and as described above with respect to FIG. 2, operation 216, the UE may receive a configuration of QCL consistency for a TRS, a pre-compensated signal transmission TO, FO, and / or PO for PDSCH and / or a TCI update for a periodic TRS and PDSCH.
[0195] At block 1218, and as described above with respect to FIG. 2, operation 218, the UE may communicate with the network entity based on the configured QCL consistency period for TRS, pre-compensated transmission signal TO, FO and / or PO, and / or TCI state for periodic TRS and PDSCH.
[0196] FIG. 13 is a flow chart diagram illustrating example operations of a method for a network entity to receive channel state information feedback including time offsets, frequency offsets, and / or phase offsets.
[0197] At block 1302, and as described above with respect to FIG. 2, operation 202, the network entity may optionally receive UE capability information regarding the UE’s capability or support for measuring and reporting one or more of time offset, frequency offset, or phase offset in CSI feedback. In some aspects, the UE may communicate with the network entity and may receive the UE capability information from the UE during an initial communication session setup process between the network entity and the UE. The UE capability information may include supported frequency bands, radio access technologies, maximum transmission power, maximum data rates, and network protocols. In some implementations, the UE may report UE capability information indicating whether the UE supports TO, FO, and / or PO measurement and reporting; whether the UE supports a joint TO, FO, and / or PO report; a supported maximum number of CSI-RS resources or CSI-RS resource sets in a CSI report for reporting TO, FO, and / or PO; a supported maximum number of configured CSI-RS resources or CSI-RS resource sets across CSI reports for reporting TO, FO, and / or PO on a per bandwidth part, per component carrier (CC) or per band basis; a supported maximum number of CSI-RS resources or CSI-RS resource sets in a slot across CSI reports for reporting TO, FO, and / or PO on a per bandwidth part, per CC or per band basis; a supported time-domain behavior for the TO, FO, and / or PO report; a supported time-domain behavior for the CSI-RS for TO, FO, and / or PO report; a supported maximum number of CSI reports for reporting TO, FO, and / or PO on a per bandwidth part, per CC, or per band.
[0198] At block 1304, and as described above with respect to FIG. 2, operation 204, the network entity may transmit, to the UE, control signaling to configure at least one CSI report configuration for CSI feedback. Based on the UE capability information, the network entity may configure one or more CSI report configurations for reporting one or more of TO, FO, or PO. Additionally, the network entity may configure one or more lists of CSI-RS resources or CSI-RS resource sets comprising CMR for use by the UE to measure characteristics of one or more channels.
[0199] At block 1306, and as described above with respect to FIG. 2, operation 206, the network entity may optionally transmit the configured measurement resources (e.g., CMRs) to the UE. In some aspects, the network entity may transmit the configured CMRs as a Medium Access Control (MAC) Control Element (CE) . In some other aspects, the network entity may transmit the CMRs as part of Downlink Control Information (DCI) .
[0200] At block 1308, and as described above with respect to FIG. 2, operation 208, the network entity may optionally transmit control signaling that triggers the UE to provide a CSI report including TO, FO, and / or PO in accordance with the CSI report configuration transmitted at block 1302. In some aspects, the MAC CE or DCI transmitted at block 1306 may trigger the UE to report the TO, FO, and / or PO based on the configured CSI report configuration (s) for a TO, FO, and / or PO report.
[0201] At block 1312, and as described above with respect to FIG. 2, operation 212, the network entity may receive a CSI report including one or more of the TO, FO, or PO from the UE. In some aspects, the network entity may receive the TO, FO, and / or PO report by physical uplink shared channel (PUSCH) or physical uplink control channel (PUCCH) .
[0202] At block 1314, and as described above with respect to FIG. 2, operation 214, the network entity may calculate pre-compensated signal transmission TOs, FOs, and / or POs based on the TOs, FOs, and / or POs received in the CSI report at block 1312. The network entity may use the pre-compensated signal transmission TOs, FOs, and / or POs when communicating with the UE.
[0203] At block 1316, and as described above with respect to FIG. 2, operation 216, the network entity may transmit, to the UE, a configuration of QCL consistency for a TRS, a pre-compensated signal transmission TO, FO, and / or PO for PDSCH and / or a TCI update for a periodic TRS and PDSCH.
[0204] At block 1318, and as described above with respect to FIG. 2, operation 218, the network entity may communicate with the UE based on the configured QCL consistency period for TRS, pre-compensated transmission signal TO, FO and / or PO, and / or TCI state for periodic TRS and PDSCH.
[0205] FIG. 14 is a block diagram illustrating example configurations of a network entity 120 and a UE 130. The UE 130 may be an implementation of any of UE 130 of FIGs. 1 and 2. Network entity 120 may be an implementation of any of network entity 120 of FIGs. 1 and 2. Note that the depicted hardware configurations represent the processing components and communication components related to UE 130 requested candidate cell configuration updates. The depicted hardware configurations may omit certain components well-understood to be frequently implemented in such electronic devices, such as displays, peripherals, power supplies, and the like.
[0206] The UE 130 includes antennas 1402, a radio frequency front end (RF front end) 1404, and radio-frequency transceivers (e.g., an LTE transceiver 1406 and a 5G NR transceiver 1408) for communicating with network entity 120, one or more TRPs, and / or one or more radio units.
[0207] The RF front end 1404 includes one or more modems configured for the corresponding RAT (s) employed (for example, 3GPP 5G NR) , one or more analog-to-digital converters (ADCs) , one or more digital-to-analog converters (DACs) , signal processors, and the like. In the example illustrated in FIG. 14, the RF front end 1404 of the UE 130 may couple or connect the LTE transceiver 1406, and the 5G NR transceiver 1408 to the antennas 1402 to facilitate various types of wireless communication. The RF front end 1404 operates, in effect, as a physical (PHY) transceiver interface to conduct and process signaling between the one or more processors 1414 and the antennas 1402 so as to facilitate various types of wireless communication.
[0208] The antennas 1402 of the UE 130 may include an array of multiple antennas that may be tuned to one or more frequency bands associated with a corresponding RAT. The antennas 1402 and the RF front end 1404 may be tuned to, and / or be tunable to, one or more frequency bands defined by the 3GPP LTE and 5G NR communication standards and implemented by the LTE transceiver 1406, and / or the 5G NR transceiver 1408. Additionally, the antennas 1402, the RF front end 1404, the LTE transceiver 1406, and / or the 5G NR transceiver 1408 may be configured to support beamforming for the transmission and reception of communications with the network entity 120, one or more TRPs, or one or more radio units. By way of example and not limitation, the antennas 1402 and the RF front end 1404 may be implemented for operation in sub-gigahertz bands, sub-6 GHz bands, and / or above 6 GHz bands that are defined by the 3GPP LTE and 5G NR communication standards.
[0209] The UE 130 also includes processor (s) 1414 and computer-readable storage media (CRM) 1416. The processor (s) 1414 may include, for example, one or more central processing units, graphics processing units (GPUs) , or other application-specific integrated circuits (ASIC) , and the like. To illustrate, the processor (s) 1414 may include an application processor (AP) utilized by the UE 130 to execute an operating system and various user-level software applications, as well as one or more processors utilized by modems or a baseband processor of the RF front end 1404. The processor (s) 1414 along with other processors of the UE 130 that are used to implement the techniques described herein may be collectively referred to as “aprocessing system. ”
[0210] CRM 1418 may include any suitable memory or storage device such as random-access memory (RAM) , static RAM (SRAM) , dynamic RAM (DRAM) , non-volatile RAM (NVRAM) , read-only memory (ROM) , Flash memory, solid-state drive (SSD) or other mass-storage devices, and the like useable to store one or more sets of executable software instructions and associated data that manipulate the one or more processors 1414 and other components of the UE 130 to perform the various functions described herein and attributed to the UE 130. The sets of executable software instructions include, for example, an operating system (OS) and various drivers (not shown) , and various software applications (not shown) , which are executable by processor (s) operation 216 to enable user-plane communication, control-plane signaling, and user interaction with the UE 130. The data 1418 stored in the CRM 1416 represents, for example, user data, multimedia data, beamforming codebooks, software application configuration information, and the like. Data 1418 may include TCI state (s) 219 and QCL parameters 1420. TCI state (s) 1419 may be data representing one or more TCI states configured on the UE 130 by network entity 120. QCL parameters 1420 may be data representing QCL parameters such as Doppler shift, Doppler spread, average delay, and / or delay spread.
[0211] CRM 1416 also includes a communications controller 1422. Alternately or additionally, the communications controller 1422 may be implemented in whole or part as hardware logic or circuitry integrated with or separate from other components of the UE 130. In some aspects, communications controller 1422 configures the RF front end 1404, the LTE transceiver 1406, and / or the 5G NR transceiver 1408 to implement the techniques described herein for a UE 130 to measure TO, FO, and / or PO and report the measured TO, FO, and PO to the network entity 120.
[0212] Turning to the hardware configuration of the network entity 120, it is noted that although FIG. 14 illustrates an implementation of the network entity 120 as a single network node (for example, a 5G NR Node B, or “gNB” ) , the functionality, and thus the hardware components, of the network entity 120 instead may be distributed across multiple network nodes or devices and may be distributed in a manner to perform the functions described herein. As one example, the functionality of network entity 120 may be distributed across a radio unit (RU) , distributed unit (DU) , or central unit (CU) .
[0213] The network entity 120 includes antennas 1452, an RF front end 1454, one or more LTE transceiver (s) 1456, and / or one or more 5G NR transceiver (s) 1458 for communicating with the UE 130. The RF front end 1454 of the network entity 120 may couple or connect the LTE transceiver (s) 1456 and the 5G NR transceiver (s) 1458 to the antennas 1452 to facilitate various types of wireless communication. Similar to RF front end operation 204, the RF front end 1454 includes one or more modems, one or more ADCs, one or more DACs, and the like. RF front end 1454 receives the one or more RF signals, for example, RF signals from UE 130, and pre-processes the one or more RF signals to generate data from the RF signals that is provided as input to processes and / or applications executing on network entity 120. This pre-processing may include, for example, power amplification, conversion of band-pass signaling to baseband signaling, initial analog-to-digital conversion, and the like.
[0214] The antennas 1452 of the network entity 120 may be configured individually and / or as one or more arrays of multiple antennas. The antennas 1452 and the RF front end 1454 may be tuned to, and / or be tunable to, one or more frequency band defined by the 3GPP LTE and 5G NR communication standards and implemented by the LTE transceiver (s) 1456, and / or the 5G NR transceivers 5G NR transceiver (s) 1458. Additionally, the antennas 1452, the RF front end 1454, the LTE transceiver (s) 1456, and / or the 5G NR transceiver (s) 1458 may be configured to support beamforming, such as Massive-MIMO, for the transmission and reception of communications with any UE 130 in a UECS.
[0215] The network entity 120 also includes processor (s) 1460 and computer-readable storage media (CRM) 1462. The processor (s) 1460 may include, for example, one or more central processing units, graphics processing units (GPUs) , or other application-specific integrated circuits (ASIC) , and the like. To illustrate, the processors processor (s) 1460 may include an application processor (AP) utilized by the network entity 120 to execute an operating system and various user-level software applications, as well as one or more processors utilized by modems or a baseband processor of the RF front end 1454 to enable communication with the UE 130.
[0216] CRM 1462 may include any suitable memory or storage device such as random-access memory (RAM) , static RAM (SRAM) , dynamic RAM (DRAM) , non-volatile RAM (NVRAM) , read-only memory (ROM) , or Flash memory useable to store device data of the network entity 120. The device data may include data 1464, which includes network scheduling data, radio resource management data, beamforming codebooks, software application configuration information, UE 130 transmitter power levels, and / or TRP configuration data and the like. Data 1464 may further include TO, FO, and / or PO report 1463, which may be time offsets and / or frequency offsets for TRPs that may be calculated by received from UE 130 according to the techniques described herein.
[0217] CRM 1462 also includes an RF resource manager 1465. In some aspects, the RF resource manager 1465 of the network entity 120 is implemented to perform various functions associated with allocating physical access (for example, resource blocks) or communication resources for the air interface of the network entity 120. The air interface of the network entity 120, may be partitioned or divided into various units (for example, frames, subframes, or slots) of one or more of bandwidth, time, symbols, or spatial layers. For example, within a framework of a 5G NR protocol, the RF resource manager 1465 may allocate bandwidth and time intervals of access in resource blocks, each of which may be allocated in whole, or in part, to one or more channels for communicating with the UE 130. The channels may include one or more of a PRACH, a PUCCH, a PUSCH, a PDCCH, a PDSCH, a PBCH, or a paging channel. The resource blocks may include multiple subcarriers that each span a portion of a frequency domain of the resource blocks. The subcarriers may be further divided into resource elements, or orthogonal frequency-division multiplexing (OFDM) symbols, that each span a portion of a time domain of the subcarriers. Consequently, a resource block includes multiple OFDM symbols that may be grouped into subcarriers with other OFDM symbols having a common frequency bandwidth.
[0218] CRM 1462 further includes network entity 1466. Alternately or additionally, the network entity 1466 may be implemented in whole or part as hardware logic or circuitry integrated with or separate from other components of the network entity 120. In at least some aspects, the network entity 1466 configures the LTE transceivers 1456 and the 5G NR transceivers 1458 for communication with the UE 130, communication with TRPs (e.g., TRPs 122A-122D of FIG. 1) via fronthaul interface 1467, as well as communication with a core network 150 (FIG. 1) .
[0219] In some aspects, the network entity 120 includes an inter-network entity interface 1468, such as an Xn and / or X2 interface, which the network entity 1466 configures to exchange user-plane and control-plane data between another network entity, to manage the communication of the network entity 120 with the UE 130. The network entity 120 includes a core network interface 1470 that the network entity 120 configures to exchange user-plane and control-plane data with core network functions and entities.
[0220] The foregoing disclosure provides illustration and description but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects. While the aspects of the disclosure have been described in terms of various examples, any combination of aspects from any of the examples is also within the scope of the disclosure. The examples in this disclosure are provided for pedagogical purposes. Alternatively, or in addition to the other examples described herein, examples include any combination of the following implementation options (enumerated as clauses for clarity) .
[0221] As used herein, the term “component” is intended to be broadly construed as hardware, firmware, or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, or a combination of hardware and software. As used herein, the phrase “based on” is intended to be broadly construed to mean “based at least in part on. ”
[0222] Some aspects are described herein in connection with thresholds. As used herein, satisfying a threshold may refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, or the like.
[0223] As used herein, a phrase referring to “at least one of” or “one or more of” a list of items refers to any combination of those items, including single members. For example, “at least one of: a, b, or c” is intended to cover the possibilities of: a only, b only, c only, a combination of a and b, a combination of a and c, a combination of b and c, and a combination of a and b and c.
[0224] In this disclosure, the term "can" indicates a capability, or alternatively indicates a possible implementation option. The term "may" indicates a permission or a possible implementation option.
[0225] The various illustrative components, logic, logical blocks, modules, circuits, operations, and algorithm processes described in connection with the implementations disclosed herein may be implemented as electronic hardware, firmware, software, or combinations of hardware, firmware, or software, including the structures disclosed in this specification and the structural equivalents thereof. The interchangeability of hardware, firmware and software has been described generally, in terms of functionality, and illustrated in the various illustrative components, blocks, modules, circuits and processes described above. Whether such functionality is implemented in hardware, firmware or software depends upon the particular application and design constraints imposed on the overall system.
[0226] The hardware and data processing apparatus used to implement the various illustrative components, logics, logical blocks, modules and circuits described in connection with the aspects disclosed herein may be implemented or performed with a general purpose single-or multi-chip processor, a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) or other programmable logic device (PLD) , discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. A processor also may be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. In some implementations, particular processes, operations, and methods may be performed by circuitry that is specific to a given function.
[0227] As described above, in some aspects implementations of the subject matter described in this specification can be implemented as software. For example, various functions of components disclosed herein, or various blocks or steps of a method, operation, process, or algorithm disclosed herein can be implemented as one or more modules of one or more computer programs. Such computer programs can include non-transitory processor-or computer-executable instructions encoded on one or more tangible processor-or computer-readable storage media for execution by, or to control the operation of, data processing apparatus including the components of the devices described herein. By way of example, and not limitation, such storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that may be used to store program code in the form of instructions or data structures. Combinations of the above should also be included within the scope of storage media. When implemented in software, the techniques can be provided as part of the operating system, a library used by multiple applications, a particular software application, etc. The software can be executed by one or more general-purpose processors or one or more special-purpose processors.
[0228] As used herein, the terms “user device” , “user equipment” (for example, UE 130) , “wireless communication device” , “mobile communication device” , “communication device” , or “mobile device” refer to any one or all of cellular telephones, smartphones, portable computing devices, personal or mobile multi-media players, laptop computers, tablet computers, smartbooks, Internet-of-Things (IoT) devices, palm-top computers, wireless electronic mail receivers, multimedia Internet enabled cellular telephones, wireless gaming controllers, display sub-systems, driver assistance systems, vehicle controllers, vehicle system controllers, vehicle communication system, infotainment systems, vehicle telematics systems or subsystems, vehicle display systems or subsystems, vehicle data controllers, point-of-sale (POS) terminals, health monitoring devices, drones, cameras, media-streaming dongles or another personal media devices, wearable devices such as smartwatches, wireless hotspots, femtocells, broadband routers or other types of routers, and similar electronic devices which include a programmable processor and memory and circuitry configured to perform operations as described herein. Further, the user device in some cases may be embedded in an electronic system such as the head unit of a vehicle or an advanced driver assistance system (ADAS) . Still further, a mobile-internet device (MID) . Depending on the type, the user device can include one or more general-purpose processors, a computer-readable memory, a user interface, one or more network interfaces, one or more sensors, etc.
[0229] Various modifications to the implementations described in this disclosure may be readily apparent to persons having ordinary skill in the art, and the generic principles defined herein may be applied to other implementations without departing from the spirit or scope of this disclosure. Thus, the claims are not intended to be limited to the implementations shown herein but are to be accorded the widest scope consistent with this disclosure, the principles and the novel features disclosed herein.
[0230] Additionally, various features that are described in this specification in the context of separate implementations also can be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation also can be implemented in multiple implementations separately or in any suitable subcombination. As such, although features may be described above as acting in particular combinations, and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.
[0231] Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. Further, the drawings may schematically depict one or more example processes in the form of a flowchart or flow diagram. However, other operations that are not depicted can be incorporated in the example processes that are schematically illustrated. For example, one or more additional operations can be performed before, after, simultaneously, or between any of the illustrated operations. In some circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products. Additionally, other implementations are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results.
[0232] The foregoing disclosure provides illustration and description but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects. While the aspects of the disclosure have been described in terms of various examples, any combination of aspects from any of the examples is also within the scope of the disclosure. The examples in this disclosure are provided for pedagogical purposes.
[0233] As used herein, the terms “component” and “module” are intended to be broadly construed as hardware, firmware, or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, or a combination of hardware and software. As used herein, the phrase “based on” is intended to be broadly construed to mean “based at least in part on. ”
[0234] Some aspects are described herein in connection with thresholds. As used herein, satisfying a threshold may refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, or the like.
[0235] As used herein, a phrase referring to “at least one of” or “one or more of” a list of items refers to any combination of those items, including single members. For example, “at least one of: a, b, or c” is intended to cover the possibilities of: a only, b only, c only, a combination of a and b, a combination of a and c, a combination of b and c, and a combination of a and b and c.
[0236] The various illustrative components, logic, logical blocks, modules, circuits, operations, and algorithm processes described in connection with the implementations disclosed herein may be implemented as electronic hardware, firmware, software, or combinations of hardware, firmware, or software, including the structures disclosed in this specification and the structural equivalents thereof. The interchangeability of hardware, firmware and software has been described generally, in terms of functionality, and illustrated in the various illustrative components, blocks, modules, circuits and processes described above. Whether such functionality is implemented in hardware, firmware or software depends upon the particular application and design constraints imposed on the overall system.
[0237] The hardware and data processing apparatus used to implement the various illustrative components, logics, logical blocks, modules and circuits described in connection with the aspects disclosed herein may be implemented or performed with processing circuitry, examples of which include a general purpose single-or multi-chip processor, a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) or other programmable logic device (PLD) , discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. A processor also may be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. In some implementations, particular processes, operations, and methods may be performed by circuitry that is specific to a given function.
[0238] As described above, in some aspects implementations of the subject matter described in this specification can be implemented as software. For example, various functions of components disclosed herein, or various blocks or steps of a method, operation, process, or algorithm disclosed herein can be implemented as one or more modules of one or more computer programs. Such computer programs can include non-transitory processor-or computer-executable instructions encoded on one or more tangible processor-or computer-readable storage media for execution by, or to control the operation of, data processing apparatus including the components of the devices described herein. By way of example, and not limitation, such storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that may be used to store program code in the form of instructions or data structures. Combinations of the above should also be included within the scope of storage media.
[0239] As used herein, the terms “user equipment” , “wireless communication device” , “mobile communication device” , “communication device” , or “mobile device” refer to any one or all of cellular telephones, smartphones, portable computing devices, personal or mobile multi-media players, laptop computers, tablet computers, smartbooks, Internet-of-Things (IoT) devices, palm-top computers, wireless electronic mail receivers, multimedia Internet enabled cellular telephones, wireless gaming controllers, display sub-systems, driver assistance systems, vehicle controllers, vehicle system controllers, vehicle communication system, infotainment systems, vehicle telematics systems or subsystems, vehicle display systems or subsystems, vehicle data controllers or routers, and similar electronic devices which include a processing circuitry such as a programmable processor, memory, and other circuitry configured to perform operations as described herein.
[0240] Various modifications to the implementations described in this disclosure may be readily apparent to persons having ordinary skill in the art, and the generic principles defined herein may be applied to other implementations without departing from the scope of this disclosure. Thus, the claims are not intended to be limited to the implementations shown herein but are to be accorded the widest scope consistent with this disclosure, the principles and the novel features disclosed herein.
[0241] Additionally, various features that are described in this specification in the context of separate implementations also can be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation also can be implemented in multiple implementations separately or in any suitable subcombination. As such, although features may be described above as acting in particular combinations, and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.
[0242] Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. Further, the drawings may schematically depict one or more example processes in the form of a flowchart or flow diagram. However, other operations that are not depicted can be incorporated in the example processes that are schematically illustrated. For example, one or more additional operations can be performed before, after, simultaneously, or between any of the illustrated operations. In some circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations and should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products. Additionally, other implementations are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results.
Claims
1.A method for wireless communication by a user equipment (UE) (130) , comprising:receiving (204, 1204) , from a network entity (120) , at least one channel state information (CSI) report configuration that configures the UE to report at least one of a time offset (TO) , a frequency offset (FO) , or a phase offset (PO) associated with one or more CSI reference signal (CSI-RS) resources;receiving (206, 1206) , from the network entity, the one or more CSI-RS resources; andtransmitting (212, 1212) , to the network entity, at least one CSI report indicating the at least one of the TO, FO, or PO for the one or more CSI-RS resources based on a reference CSI-RS resource.2.The method of claim 1, wherein the one or more CSI-RS resources are configured in one or more CSI-RS resource sets.3.The method of any of claims 1 or 2, further comprising measuring (210, 1210) the at least one of the TO, FO, or PO based on a first CSI-RS resource of the one or more CSI-RS resources corresponding to the reference CSI-RS resource and a second CSI-RS resource of the one or more CSI-RS resources corresponding to a non-reference CSI-RS resource.4.The method of claim 3, wherein the measuring the at least one of the TO, FO, or PO includes calculating at least one of:a minimum value of the TO across a plurality of antenna ports of the UE;a minimum value of the FO across the plurality of antenna ports;a minimum value of the PO across the plurality of antenna ports;a maximum value of the TO across the plurality of antenna ports;a maximum value of the FO across the plurality of antenna ports;a maximum value of the PO across the plurality of antenna ports;an average value of the TO across the plurality of antenna ports;an average value of the FO across the plurality of antenna ports; oran average value of the PO across the plurality of antenna ports.5.The method of any of claims 1-4, wherein the CSI report configuration further includes a report subset restriction indicating a subset of the one or more CSI-RS resources to be used for channel measurement, wherein the transmitting the at least one CSI report includes transmitting the at least one CSI report based on the report subset restriction.6.The method of claim 3, wherein the measuring the at least one of the TO, FO, or PO includes measuring the at least one of the TO, FO, or PO in accordance with a time restriction.7.The method of any one of claims 1-6, wherein the transmitting the least one CSI report, includes transmitting the at least one CSI report in response to at least one of:receiving at least one transmission of each of the one or more CSI-RS resources;determining that a scheduling for the CSI report meets a minimum processing delay requirement; ordetermining that a total number of CSI processing units (CPUs) for the CSI report and one or more other CSI reports is less than a maximum number of CPUs.8.The method of any one of claims 1-7, further comprising receiving, from the network entity, a configuration of least one of:a quasi-co-location (QCL) consistency period;a first indication of a pre-compensated signal transmission TO;a second indication of a pre-compensated signal transmission FO;a third indication of a pre-compensated signal transmission PO; ora transmission configuration indicator (TCI) state for a periodic tracking reference signal (TRS) and a physical downlink shared channel (PDSCH) .9.The method of claim 8, further comprising:measuring at least one QCL parameter based on the one or more CSI-RS resources and at least one of the first indication of the pre-compensated signal transmission TO, the second indication of the pre-compensated signal transmission FO, or the third indication of the pre-compensated signal transmission PO.10.The method of claim 8, wherein the UE determines a same value for at least one QCL parameter during the QCL consistency period.11.The method of any one of claims 1-10, further comprising:when a payload size for a CSI part exceeds a maximum payload size for the CSI part, omitting one or more TOs, one or more FOs, or one or more POs from the at least one CSI report.12.The method of any one of claims 1-11, further comprising transmitting UE capability information including at least one of:a first indicator indicating whether the UE supports measuring and reporting the at least one of the TO, FO, or PO;a second indicating whether the UE supports joint reporting of the at least one of the TO, FO, or PO;a first maximum number of first CSI-RS resources in the at least one CSI report;a second maximum number of second CSI-RS resources across a first plurality of CSI reports per at least one of a bandwidth part, a component carrier, or a band;a third maximum number of third CSI-RS resources in a slot across a plurality of CSI reports per at least one of the bandwidth part, the component carrier, or the band;a first supported time-domain behavior for the at least one CSI report;a second supported time-domain behavior for the one or more CSI-RS resources; ora fourth maximum number of CSI reports per at least one of the bandwidth part, the component carrier, or the band.13.A method for wireless communications by a network entity (120) , comprising:transmitting (204, 1304) , to a user equipment (UE) (130) , at least one channel state information (CSI) report configuration that configures the UE to report at least one of a time offset (TO) , a frequency offset (FO) , or a phase offset (PO) associated with one or more CSI reference signal (CSI-RS) resources;transmitting (206, 1306) , to the UE, the one or more CSI-RS resources; andreceiving (212, 1312) , from the UE, at least one CSI report indicating the at least one of the TO, FO, or PO for the one or more CSI-RS resources based on a reference CSI-RS resource.14.The method of claim 13, wherein the transmitting the CSI report configuration includes transmitting the CSI report configuration in response to a determination of at least one of:a first number of resource blocks is above or equal to a first threshold;a second number of first subcarriers in a symbol is above or equal to a second threshold;a third number of second subcarriers per resource block is above or equal to a third threshold;a fourth number of antenna ports of the UE is below a fourth threshold; orthe one or more CSI-RS resources are included in at least one CSI-RS resource set for tracking.15.The method of claim 13 or 14, further comprising:calculating (214, 1214) at least one of a pre-compensated signal transmission TO or a pre-compensated signal transmission FO based on at least one of the TO, FO, or PO; andtransmitting (216, 1216) , to the UE, a configuration indicating the at least one of the pre-compensated signal transmission TO or the pre-compensated signal transmission FO.16.The method of claim 15, wherein the configuration includes an indicator of a quasi-co-location (QCL) consistency period associated with the at least one of the pre-compensated signal transmission TO or the pre-compensated signal transmission FO.17.An apparatus, comprising:a communication unit; anda processing system configured to control the communication unit to implement any one of the methods of any one of claims 1-16.