Codebook design for mtrp coherent joint transmission with predictive csi

Abstract

An apparatus configured to process, based on signaling received from a base station, configuration information for reporting channel state information (CSI) using a Type-II codebook that jointly supports CSI feedback for multiple transmission reception point (mTRP) coherent joint transmission (CJT) and CSI feedback with time domain compression, process, based on signaling received from the base station, CSI measurement resources and generate, for transmission to the base station, Type-II codebook based CSI feedback to the base station.

Description

Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1 Codebook Design for mTRP Coherent Joint Transmission with Predictive CSI Inventors: Weidong Yang, Ankit Bhamri, Dawei Zhang, Haitong Sun, Hong He, Huaning Niu, Seyed Ali Akbar Fakoorian and Wei Zeng Priority / Incorporation By Reference

[0001] This application claims priority to U.S. Provisional Application Serial No. 63 / 604,263 filed on November 30, 2023, entitled “Codebook Design for mTRP Coherent Joint Transmission with Predictive CSI,” the entirety of which is incorporated by reference herein. Background

[0002] A user equipment (UE) may connect to a Fifth Generation (5G) New Radio (NR) network. The 5G NR network may support codebook-based beamforming and feedback that enables a variety of different channel state information (CSI) acquisition mechanisms. It has been identified that there is a need for a codebook that jointly supports CSI feedback for multi- transmission reception point (mTRP) coherent joint transmission (CJT) and CSI feedback with time domain compression CSI. Summary

[0003] Some example embodiments are related to an apparatus having processing circuitry coupled to memory, the processing circuitry configured to process, based on signaling received from a base station, configuration information for reporting channel state information (CSI) using a Type-II codebook that jointly supports CSI feedback for multiple transmission reception point (mTRP) coherent joint transmission (CJT) and CSI feedback with time domain compression, process, based on signaling received from the base station, CSI measurementAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 resources and generate, for transmission to the base station, Type-II codebook based CSI feedback to the base station.

[0004] Other example embodiments are related to a method including processing, based on signaling received from a base station, configuration information for reporting channel state information (CSI) using a Type-II codebook that jointly supports CSI feedback for multiple transmission reception point (mTRP) coherent joint transmission (CJT) and CSI feedback with time domain compression, processing, based on signaling received from the base station, CSI measurement resources and generating, for transmission to the base station, Type-II codebook based CSI feedback to the base station. Brief Description of the Drawings

[0005] Fig. 1 shows an example network arrangement according to various example embodiments.

[0006] Fig. 2 shows an example user equipment (UE) according to various example embodiments.

[0007] Fig. 3 shows an example base station according to various example embodiments.

[0008] Fig. 4 shows a signaling diagram for reporting channel state information (CSI) feedback according to various example embodiments.

[0009] Fig. 5 which shows a timeline for CSI reporting with CSI prediction according to various example embodiments.

[0010] Fig. 6 shows tables illustrating examples of different combinations for common and independent selection of parametersAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 for common joint transmission (CJT)-time domain (TD)-CSI codebook according to various example embodiments.

[0011] Fig. 7 shows a table illustrating examples of different coefficient grouping methods according to various example embodiments. Detailed Description

[0012] The example embodiments may be further understood with reference to the following description and the related appended drawings, wherein like elements are provided with the same reference numerals. The example embodiments relate to a codebook that jointly supports channel state information (CSI) feedback for multi-transmission reception point (mTRP) coherent joint transmission (CJT) and CSI feedback with time domain compression.

[0013] The example embodiments are described with regard to a user equipment (UE). However, reference to a UE is merely provided for illustrative purposes. The example embodiments may be utilized with any electronic component that may establish a connection to a network and is configured with the hardware, software, and / or firmware to exchange information and data with the network. Therefore, the UE as described herein is used to represent any electronic component.

[0014] The example embodiments are also described with regard to a Fifth Generation (5G) New Radio (NR) network and a next generation node B (gNB). However, reference to a 5G NR network and a gNB is merely provided for illustrative purposes. The example embodiments may be utilized with any appropriate type of network (e.g., 5G-Advanced, 6G, etc.) and base station.Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1

[0015] The gNB may be configured with multiple transmission and reception points (TRPs). Throughout this description, a TRP generally refers to a set of components configured to transmit and / or receive a beam. In some embodiments, multiple TRPs may be deployed locally at the gNB. For example, the gNB may include multiple antenna arrays / panels that are each configured to generate a different beam. In other embodiments, multiple TRPs may be deployed at different geographical locations and connected to the gNB via a backhaul connection. For example, multiple small cells / remote radio heads may be deployed at different locations and connected to the gNB. However, these examples are merely provided for illustrative purposes. TRPs may be configured to be adaptable to a wide variety of different conditions and deployment scenarios. Thus, any reference to a TRP being a particular network component or multiple TRPs being deployed in a particular arrangement is merely provided for illustrative purposes. The TRPs described herein may represent any type of network component configured to transmit and / or receive a beam.

[0016] The example embodiments are described with regard to multi-TRP (mTRP) operation. From the perspective of the UE, multi-transmission reception point (mTRP) operation may include establishing and maintaining a connection with multiple TRPs at the same time. For example, different channel state information (CSI)-reference signals (RS) resource sets may be configured for different TRPs to support CSI measurement.

[0017] The 5G NR network may support a codebook-based for CSI feedback. The example embodiments are described with regard to CSI feedback for mTRP CJT and CSI feedback with time domainAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 compression. However, reference to the terms mTRP CJT and time domain compressions are merely provided for illustrative purposes. Different entities may refer to similar concepts by a different name.

[0018] CSI feedback with time domain compression generally refers to codebook-based CSI feedback where multiple doppler components for a single spatial layer may be used to represent precoders suitable for the propagation channel between the base station and the UE. This CSI feedback may be referred to as TD- CSI and include CSI corresponding to the time location of the channel measurement resources transmitted by the network and predicted CSI corresponding to one or more time locations in the future. The UE may use precoders from a codebook to provide the predictive CSI to the network. Throughout this description, the terms predictive CSI, time domain compression, time domain prediction and TD-CSI may generally refer to the same concept and be used interchangeably.

[0019] mTRP CJT generally refers to a scheme where multiple TRPs may concurrently transmit a signal over the same frequency to the UE. The UE may use a precoder from a codebook to provide the CSI feedback for mTRP CJT to the network.

[0020] As will be described in more detail below, the example embodiments include features that enable the implementation of a codebook that jointly support CSI feedback for mTRP CSI and CSI feedback with time domain compression. The example embodiments may be used in independently from one another, in conjunction with currently implemented CSI feedback mechanisms, in conjunction with future implementations of CSI feedback mechanisms or independently from other CSI feedback mechanisms.Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1

[0021] Fig. 1 shows an example network arrangement 100 according to various example embodiments. The example network arrangement 100 includes a UE 110. The UE 110 may be any type of electronic component that is configured to communicate via a network, e.g., mobile phones, tablet computers, desktop computers, smartphones, phablets, embedded devices, wearables, Internet of Things (IoT) devices, etc. An actual network arrangement may include any number of UEs being used by any number of users. Thus, the example of a single UE 110 is merely provided for illustrative purposes.

[0022] The UE 110 may be configured to communicate with one or more networks. In the example of the network configuration 100, the network with which the UE 110 may wirelessly communicate is a 5G NR radio access network (RAN) 120. However, the UE 110 may also communicate with other types of networks (e.g., sixth generation (6G) RAN, 5G cloud RAN, a next generate RAN (NG-RAN), a legacy cellular network, a wireless local area network (WLAN), etc.) and the UE 110 may also communicate with networks over a wired connection. Therefore, the UE 110 may have a 5G NR chipset to communicate with the NR RAN 120 and, optionally, any other appropriate type of chipset to communicate with other types of networks.

[0023] The 5G NR RAN 120 may be a portion of a cellular network that may be deployed by a network carrier (e.g., Verizon, AT&T, Sprint, T-Mobile, etc.). The 5G NR RAN 120 may include base stations that are configured to send and receive traffic from UEs that are equipped with the appropriate cellular chip set. In this example, the 5G NR RAN 120 includes the gNB 120A. However, reference to a gNB is merely provided for illustrative purposes, the example embodiments may be utilizedAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 with any appropriate type of access node (e.g., Node Bs, eNodeBs, HeNBs, eNBs, gNBs, gNodeBs, macrocells, microcells, small cells, femtocells, etc.).

[0024] In the network arrangement 100, the 5G NR RAN 120 deploys a gNB 120A. The gNB 120A may be configured with multiple TRPs. Each TRP may represent one or more components configured to transmit and / or receive a signal. In some embodiments, multiple TRPs may be deployed locally at the gNB 120A. In other embodiments, multiple TRPs may be distributed at different locations / remote radio heads and connected to the gNB 120A via a backhaul connection or multiple fronthaul connections. For example, multiple small cells may be deployed at different locations and connected to the gNB 120A. In other embodiments, the gNB 120A represents multiple base stations deployed at different locations where one or more TRPs are controlled by a first gNB and one or more TRPs are controlled by a second different gNB. However, these examples are merely provided for illustrative purposes. TRPs may be configured to be adaptable to a wide variety of different conditions and deployment scenarios. Thus, any reference to a TRP being a particular network component or multiple TRPs being deployed in a particular arrangement is merely provided for illustrative purposes. The TRPs described herein may represent any type of network component configured to transmit and / or receive a beam.

[0025] Any association procedure may be performed for the UE 110 to connect to the 5G NR RAN 120. For example, as discussed above, the 5G NR RAN 120 may be associated with a particular network carrier where the UE 110 and / or the user thereof has a contract and credential information (e.g., stored on a SIM card). Upon detecting the presence of the 5G NR RAN 120, the UEAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 110 may transmit the corresponding credential information to associate with the 5G NR RAN 120. More specifically, the UE 110 may associate with a specific cell (e.g., the gNB 120A).

[0026] The network arrangement 100 also includes a cellular core network 130, the Internet 140, an IP Multimedia Subsystem (IMS) 150, and a network services backbone 160. The cellular core network 130 may refer an interconnected set of components that manages the operation and traffic of the cellular network. The cellular core network 130 also manages the traffic that flows between the cellular network and the Internet 140. The IMS 150 may be generally described as an architecture for delivering multimedia services to the UE 110 using the IP protocol. The IMS 150 may communicate with the cellular core network 130 and the Internet 140 to provide the multimedia services to the UE 110. The network services backbone 160 is in communication either directly or indirectly with the Internet 140 and the cellular core network 130. The network services backbone 160 may be generally described as a set of components (e.g., servers, network storage arrangements, etc.) that implement a suite of services that may be used to extend the functionalities of the UE 110 in communication with the various networks.

[0027] Fig. 2 shows an example UE 110 according to various example embodiments. The UE 110 will be described with regard to the network arrangement 100 of Fig. 1.

[0028] The UE 110 may include a processor 205, a memory arrangement 210, a display device 215, an input / output (I / O) device 220, a transceiver 225 and other components 230. The other components 230 may, for example, an audio input device, an audio output device, a power supply, a data acquisition device,Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1 ports to electrically connect the UE 110 to other electronic devices, etc.

[0029] The processor 205 may be configured to execute a plurality of engines of the UE 110. For example, the engines may include a CJT-TD-CSI engine 235. The CJT-TD-CSI engine 235 may perform various operations related to codebook-based beam management such as, but not limited to, receiving CSI feedback configuration information, receiving channel measurement resources, compiling CSI and transmitting CSI feedback to the network.

[0030] The above referenced engine 235 being an application (e.g., a program) executed by the processor 205 is merely provided for illustrative purposes. The functionality associated with the engine 235 may also be represented as a separate incorporated component of the UE 110 or may be a modular component coupled to the UE 110, e.g., an integrated circuit with or without firmware. For example, the integrated circuit may include input circuitry to receive signals and processing circuitry to process the signals and other information. The engines may also be embodied as one application or separate applications. In addition, in some UEs, the functionality described for the processor 205 is split among two or more processors such as a baseband processor and an applications processor. The example embodiments may be implemented in any of these or other configurations of a UE.

[0031] The memory arrangement 210 may be a hardware component configured to store data related to operations performed by the UE 110. The display device 215 may be a hardware component configured to show data to a user while the I / O device 220 mayAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 be a hardware component that enables the user to enter inputs. The display device 215 and the I / O device 220 may be separate components or integrated together such as a touchscreen.

[0032] The transceiver 225 may be a hardware component configured to establish a connection with the 5G NR-RAN 120, an LTE-RAN (not pictured), a legacy RAN (not pictured), a WLAN (not pictured), etc. Accordingly, the transceiver 225 may operate on a variety of different frequencies or channels (e.g., set of consecutive frequencies). The transceiver 225 includes circuitry configured to transmit and / or receive signals (e.g., control signals, data signals). Such signals may be encoded with information implementing any one of the methods described herein. The processor 205 may be operably coupled to the transceiver 225 and configured to receive from and / or transmit signals to the transceiver 225. The processor 205 may be configured to encode, decode and / or process signals (e.g., signaling from a base station of a network) for implementing any one of the methods described herein.

[0033] Fig. 3 shows an example base station 300 according to various example embodiments. The base station 300 may represent the gNB 120A or any other access node through which the UE 110 may establish a connection and manage network operations.

[0034] The base station 300 may include a processor 305, a memory arrangement 310, an input / output (I / O) device 315, a transceiver 320, TRPs 325 and other components 330. The other components 330 may include, for example, an audio input device, an audio output device, a battery, a data acquisition device, ports to electrically connect the base station 300 to otherAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 electronic devices and / or power sources, TxRUs, transceiver chains, antenna elements, antenna panels, etc.

[0035] As indicated above, in some scenarios, the TRPs 325 may be deployed locally at the base station 300. In other scenarios, the TRPs 325 may be deployed at physical locations remote from the base station 300 and connected to the base statin via a backhaul connection. The base station 300 may be configured to control the TRPs 325 and perform operations such as, but not limited to, assigning resources, configuring reference signals, implementing beam management techniques, etc.

[0036] The processor 305 may be configured to execute a plurality of engines of the base station 300. For example, the engines may include a CJT-TD-CSI engine 335. The CJT-TD-CSI engine 335 may perform various operations related enabling codebook-based CSI feedback such as, but not limited to, transmitting CSI feedback configuration information, transmitting channel measurement resources and receiving CSI feedback from the UE 110.

[0037] The above noted engine 335 being an application (e.g., a program) executed by the processor 305 is only example. The functionality associated with the engine 335 may also be represented as a separate incorporated component of the base station 300 or may be a modular component coupled to the base station 300, e.g., an integrated circuit with or without firmware. For example, the integrated circuit may include input circuitry to receive signals and processing circuitry to process the signals and other information. In addition, in some base stations, the functionality described for the processor 305 is split among a plurality of processors (e.g., a basebandAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 processor, an applications processor, etc.). The example embodiments may be implemented in any of these or other configurations of a base station.

[0038] The memory 310 may be a hardware component configured to store data related to operations performed by the base station 300. The I / O device 315 may be a hardware component or ports that enable a user to interact with the base station 300.

[0039] The transceiver 320 may be a hardware component configured to exchange data with the UE 110 and any other UE in the network arrangement 100. The transceiver 320 may operate on a variety of different frequencies or channels (e.g., set of consecutive frequencies). The transceiver 320 includes circuitry configured to transmit and / or receive signals (e.g., control signals, data signals). Such signals may be encoded with information implementing any one of the methods described herein. The processor 305 may be operably coupled to the transceiver 320 and configured to receive from and / or transmit signals to the transceiver 320. The processor 305 may be configured to encode, decode and / or process signals (e.g., signaling from a UE) for implementing any one of the methods described herein.

[0040] Fig. 4 shows a signaling diagram 400 for reporting CSI feedback according to various example embodiments. The signaling diagram 400 is described with regard to the network arrangement 100 of Fig. 1, the UE 110 of Fig. 2 and the base station 300 of Fig. 3.

[0041] The signaling diagram 400 is described with regard to a scenario in which the UE 110 reports CSI to the gNB 120A.Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1 Initially, a general overview of this example scenario is described below to provide context for the example embodiments introduced herein. The example embodiments include features to support the implementation of a codebook that jointly supports CSI feedback for mTRP CJT and CSI feedback with time domain compression. Each of the example embodiments will be described in detail below after the description of the signaling diagram 400.

[0042] In 405, the UE 110 receives CSI configuration information from the gNB 120A. The configuration information may be for reporting CSI feedback for mTRP CJT with time domain compression (CJT-TD-CSI) using a codebook that jointly supports CSI feedback for mTRP CJT and predictive CSI. The configuration information may include, but is not limited to, configuration information for CSI measurement resources, the type of CSI to be reported and CSI reporting parameters (e.g., periodicity, slot offset, etc.).

[0043] The CSI configuration information may be provided to the UE 110 in one or more Radio Resource Control (RRC) messages. However, the example embodiments are not limited to RRC messages. Alternatively, or in addition to RRC messages, CSI configuration information may be provided in a medium access control (MAC) control element (CE), downlink control information (DCI) or any other appropriate type of signal. For example, a MAC CE and / or DCI may be configured to activate and deactivate sets of CSI measurement resources, indicate a CSI report periodicity and slot offset, indicate a codebook type (e.g., mode 1, mode 2, etc.), change a configuration of a CSI parameter previously configured by an RRC message or provide any other type of configuration information relevant to reporting CSI.Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1

[0044] The CSI configuration information may include configuration information for the CSI measurement resources. The CSI measurement resources may be provided using synchronization signal block (SSB), CSI-reference signal (RS) or any other appropriate type of signal. The periodicity and offset of these resources may be characterized in slots or in any other appropriate manner. Throughout this description, any reference to a particular type of CSI measurement resource is merely provided for illustrative purposes, the example embodiments may apply to any appropriate type of CSI measurement resource.

[0045] In 410, the UE 110 receives CSI measurement resources. In the signaling diagram 400, the CSI measurement resources are transmitted by the gNB 120A. However, in an actual deployment scenario, the UE 110 may receive CSI measurement resources from multiple cells including cells deployed by a gNB or base station other than the gNB 120A.

[0046] In 415, the UE 110 transmits a CSI report to the gNB 120A. The contents of the CSI report and the transmission of the CSI report may be based on the CSI configuration information provided by the gNB 120A in 405. The CSI report may include one or more different types of CSI (e.g., precoding matrix indicator (PMI), channel quality indicator (CQI), rank indicator (RI), etc.) derived based on CSI measurement resources.

[0047] From a single CSI report, the gNB 120A may determine precoders to be applied to multiple occasions of downlink transmissions. However, channel conditions may vary over time and the contents of the CSI report (e.g., recommended PMI, CQI, RI, etc.) may become obsolete. The example embodiments use a codebook for CSI feedback that exploits the doppler domain byAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 using time domain compression. The example codebook enables CSI feedback with a validity time longer than legacy CSI feedback.

[0048] In 5G NR codebooks, precoders for a layer may be givenby a size ^^ × ^^3 matrix ^^ = ^^1 ∗ ^̃^2 ∗ ^^^^^^structure where ^^ represents spatial and ^^3represents frequencydomain (FD) dimensions. In addition, ^^1represents beam selection, ^̃^2represents a combination coefficient for bitmap and quantization design and ^^^^^^represents FD basis selection. The number of selected basis ^^ for ^^1and the number ofselected frequency basis ^^ for ^^2may be by thenetwork.

[0049] In release 18 (Rel-18), a Type-II codebook enhancement for mTRP CJT includes support of a two codebook structure comprising mode 1 and mode 2. Mode 1 refers to an independent frequency basis selection across ^^ TRPs. An example formulation of a Type-II codebook for CJT mTRP mode 1 may be represented as ^^,1^ ^^ 1 ̃^2,1^^^^,1]

[0050] Mode 2 refers to a common frequency basis selection across all TRPs. An example formulation of a Type-II codebook ^^ ^̃^ ^^ ^^ 1,1 2,1 ^^for CJT mTRP mode 2 may be represented as ] ^^

[0051] Rel-18 also includes a Type-II codebook enhancement for CSI prediction. An example of CSI prediction is illustrated in Fig. 5 which shows a timeline 500 for CSI reporting with CSI prediction according to various example embodiments. In thisAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 example, ^^ represents an offset between adjacent aperiodic-CSI- reference signal (AP-CSI-RS) resources for channel measurementin slots ^^ ∈ {1,2}, ^^ represents the number of AP-CSI-RS resourcesfor channel measurement, ^^ represents the number of slots from the slot of the CSI report to the first predicted CSI, ^^4represents a number of predicted CSI and ^^ represents distancebetween two predicted CSI slots. For periodic / semi-persistent CSI-RS, ^^ equals to the periodicity of the CSI-RS resource andfor aperiodic CSI-RS ^^ ∈ {1, ^^} slots. A number of selectedtime / doppler basis ^^ ∈ {2} for ^^4 > 1.

[0052] As mentioned above, the example embodiments relate to a codebook that supports both CSI feedback for mTRP CJT and predictive CSI feedback. This is in contrast to the Rel-18 enhancements which do not support TD-CSI for mTRP.

[0053] According to some aspects, the example embodiments introduce measurement resource configurations that may be used for a CJT-TD-CSI report. Throughout this description, a CJT-TD- CSI report may refer to any CSI report for codebook-based CSI feedback that uses a codebook that jointly supports mTRP CJT and CSI feedback for time domain compression.

[0054] In the examples below, ^^^^^^^^represents a number of TRPs with measurement resources. The actual number of selected TRPs may be smaller than ^^^^^^^^. Further, ^^ represents a number of CSI- RS resources for channel measurement at a TRP. In some examples,^^ ∈ {4, 8, 12}.

[0055] For CJT-TD-CSI reports, the measurement resources may be configured in any of a variety of different ways. In oneapproach, ^^^^^^^^ × ^^ CSI-RS resources may be configured for the UEAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1110. For example, CSI-RS resources 0, 1, … , ^^^^^^^^ − 1 may be configuredfor TRP #0 to ^^^^^^^^ − 1 for time occasion #0, CSI-RS resources 0 +^^, 1 + ^^, … , ^^^^^^^^ − 1 + ^^ may be configured for TRP #0 to ^^^^^^^^ − 1 fortime occasion #1, etc.

[0056] In another approach, ^^ × ^^^^^^^^ CSI-RS resources may beconfigured for the UE 110. For example, CSI-RS resources 0, 1, … ^^ −1 may be configured for TRP #0 for time occasion #0 to ^^ − 1,CSI-RS resources ^^^^^^^^ + 0, ^^^^^^^^ + 1, … , ^^^^^^^^ + ^^ − 1 may be configured fortime occasion 0 to ^^ − 1.

[0057] In a further approach, ^^ CSI-RS resource sets may be configured for the UE 110. Each CSI-RS resource set may comprise of ^^^^^^^^CSI-RS resources. In this example, a CSI-RS resource set may be configured with a common slot offset with regard to another CSI-RS resource set.

[0058] In another approach, ^^^^^^^^CSI-RS resource sets may be configured for the UE 110. Each CSI-RS resource set may comprise of ^^ CSI-RS resources. In this example, a CSI-RS resource from a first CSI-RS resource set may be in a same location of CSI-RS resources from a second different CSI-RS resource set and associated with a same time occasion.

[0059] According to some aspects, the example embodiments introduce features for the structure of a codebook that jointly supports CSI feedback for mTRP CJT and CSI feedback with time domain compression.

[0060] In some examples, a two-codebook structure comprising mode 1 and mode 2 may be used. Mode 1 refers to an independent frequency basis selection across ^^ TRPs. An example formulationAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 of a Type-II codebook for CJT-TD-CSI mode 1 may be represented ^^1,1^̃^2,1(^^^^,1^^^^^,1) ^^ as follows: [ ⋮ ] ^

[0061] common frequency basis selection across all TRPs. An example formulation of a Type-II codebook for CJT-TD-CSI mode 2 may be represented as follows: ^^1,1^̃^2,1(^^^^^^^^^,1) ^^ [ ] represents spatial beam , ^̃^ represents a2combination coefficient for bitmap and quantization design, ^^^^^^or ^^^^^,^∗ represents FD basis selection (e.g., time domainand ^^^^represent doppler domain basis selection (e.g., doppler domain selection). Generally, selecting or utilizing fewer spatial beams, fewer FD bases, fewer doppler domain bases provide the benefit of smaller CSI feedback overhead.

[0063] According to some aspects, the example embodiments introduce techniques for spatial domain selection, time domain selection, doppler domain selection and nonzero coefficient subset selection. For CJT-TD-CSI, the spatial domain basis selection may consider polarization, spatial layers and TRPs. Similarly, for CJT-TD-CSI, the time domain selection may consider polarization, spatial layers and TRPs. In addition, the doppler domain selection may consider polarization, spatial layers and TRPs. Further, for CJT-TD-CSI, the nonzero coefficient subset selection may consider polarization, spatial layers and TRPs.Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1

[0064] Generally, common selection leads to lower signaling overhead and independent selection leads to higher throughput. Accordingly, for CJT-TD-CSI, there is a tradeoff between signaling overhead and throughput based on whether an independent selection is used for zero or more of polarization, layer and TRPs and / or whether a common selection is used for zero or more of polarization, spatial layer and TRPs.

[0065] Fig. 6 shows tables 600-650 illustrating examples of different combinations for common and independent selection of parameters for CJT-TD-CSI codebook according to various example embodiments. The examples shown in tables 600-610 have been identified as providing an adequate balance between signaling overhead and throughput. However, the example embodiments are not limited to these examples and may use any combination of common / independent selection for CJT-TD-CSI.

[0066] Table 600 includes column 610 comprising spatial domain basis, frequency domain basis, doppler domain basis and nonzero coefficient subset for CJT-TD-CSI. Column 612 shows that a common selection is conducted across polarizations for the spatial domain basis, the frequency domain basis and doppler domain basis while a different coefficient subset selection is used for polarization. Column 614 shows that common selection is conducted across layers for the spatial domain basis and an independent selection is conducted at layers for each of the frequency domain basis, doppler domain basis and coefficient subset selection. Column 616 shows that an independent selection is conducted across TRPs for each of the spatial domain basis, frequency domain basis, doppler domain basis and coefficient subset selection.Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1

[0067] Table 650 includes column 660 comprising spatial domain basis, frequency domain basis, doppler domain basis and coefficient subset for CJT-TD-CSI. Column 662 shows that a common selection is conducted across polarizations for the spatial domain basis, the frequency domain basis and doppler domain basis while a different coefficient subset selection is used for different polarizations. Column 664 shows that common selection is conducted across layers for the spatial domain basis and an independent selection is conducted across layers for each of the frequency domain basis, doppler domain basis and coefficient subset selection. Column 666 shows that independent selection is conducted across TRPs for each of the spatial domain basis, doppler domain basis and coefficient subset selection while the frequency domain basis is independently selected at TRPs.

[0068] According to some aspects, the example embodiments introduce techniques for providing a strongest coefficient indication. For CJT-TD-CSI, the strongest coefficient among all TRPs may be indicated for spatial layer ^^. Initially, assume that the strongest coefficient may be associated with (^^∗^^, ^^∗^^, ^^∗^^, ^^^∗^) where^^∗ represents a spatial beam index (with the range of [0, ^^ − 1] ifpolarization indication for the strongest coefficient isseparately carried, otherwise the range of [0,2 ∙ ^^ − 1]), ^^∗ mayrepresent an FD component index and ^^∗ = 0 may be assumed in somedesigns, ^^∗may represent the selected TRP index, ^^^∗^ may represent the doppler component index. In some embodiments, ^^∗^^ = 0may be assumed. That is, subtracting the carrieroffset of the strongest coefficient to all coefficients thereby the strongest coefficient may be moved to DC. In otherAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 embodiments, a more general formulation may use ^^∗ ^^as the selected TRP index at the spatial later.

[0069] To facilitate efficient coefficient quantization, the nonzero coefficients may be divided into one or more coefficient groups. The strongest coefficient belongs to one of the coefficient groups and the grouping may be performed according to one or more factors such as, but not limited to, polarization doppler domain basis and TRP. An example of this technique is shown in table 700 of Fig. 7.

[0070] In some embodiments, the strongest coefficient within a group may be used as reference for the rest of coefficients in that group. The strongest coefficient within that group may be quantized with high resolution for amplitude and / or phase, and the rest of the coefficients may be normalized according to quantized strongest coefficient. The normalization may be for amplitude only or for both amplitude and phase. The normalized coefficients may be quantized with lower resolution for amplitude or with lower resolutions for both amplitude and phase. If quantized rest coefficients are zero or near zero, or weaker than some other coefficients (e.g., subject to feedback overhead limit), they can be omitted in the feedback, and their absence is indicated by “0” in a bitmap (or any other appropriate type of indication). Depending on the choices as shown in Tables 600 and 650, one or more bitmaps may be used.

[0071] Fig. 7 shows a table 700 illustrating examples of different coefficient grouping methods according to various example embodiments.

[0072] Column 710 of the table 700 shows four different coefficient grouping methods 702-708. The example embodimentsAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 are not limited to the examples shown in the table 700 and may configure the coefficient groups in any appropriate manner.

[0073] Column 718 shows a number of groups used for each grouping method. In this example, grouping method 702 uses 2^^ groups, grouping method 704 uses 2 groups, grouping method 706 uses ^^ groups and grouping method 708 uses 1 group.

[0074] Column 712 shows whether polarization is considered as a factor for the corresponding grouping method. Column 714 shows whether doppler domain basis is considered as a factor for the corresponding grouping method. Column 716 shows whether TRP is considered as a factor for the corresponding grouping method.

[0075] Except for the group that contains the strongest coefficient, in each group, the locally strongest coefficient may be identified and normalized with the globally strongest coefficient and quantized. In some embodiments, the quantization may be with a high-resolution amplitude quantization.

[0076] According to some aspects, the example embodiments introduce parameters for an example Type-II codebook that jointly supports CJT and TS-CSI. The examples provided below are not intended to limit the example embodiments in any way and is provided as one example of parameters that may be used to implement the example embodiments. Parameter UCI Details / description Comments # NZ Part RI (^{1 RI }) and K (the total Across Q Doppler at ^^^orAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 CSI-RS Part Only reported when N >1: resource 1 N -bit bitmap to indicate the UE selection recommendation of N groups of CSI-RS ^^ ^^ex , o a ex of ex , ex esAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 basis selection for TRPs, including ^^^^, e orSCI and FD basis subset selection indicator SCI for RI>1Per-layer SCI defined across N TRPs, where is ad s sAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 Combinatorial indicator for bits

[0077] In a first example, a method, comprising, processing, based on signaling received from a base station, configuration information for reporting channel state information (CSI) using a Type-II codebook that jointly supports CSI feedback for multiple transmission reception point (mTRP) coherent joint transmission (CJT) and CSI feedback with time domain compression, processing, based on signaling received from the base station, CSI measurement resources and generating, for transmission to the base station, Type-II codebook based CSI feedback.

[0078] In a second example, the method of the first example, wherein ^^^^^^^^represents a number of TRPs with measurement resources and ^^ represents a number of CSI-reference signal (RS)resources for channel measurement at a TRP, and wherein ^^^^^^^^ × ^^CSI-RS resources are configured for the UE, CSI-RS resources0, 1, … , ^^^^^^^^ − 1 are for a first TRP to ^^^^^^^^ − 1 for a first timeoccasion and CSI-Rs resources 0 + ^^, 1 + ^^, … , ^^^^^^^^ − 1 + ^^ are for thefirst TRP to ^^^^^^^^ − 1 for a second time occasion.

[0079] In a third example, the method of the first example, wherein ^^^^^^^^represents a number of TRPs with measurement resources and ^^ represents a number of CSI-reference signal (RS)resources for channel measurement at a TRP, and wherein ^^ × ^^^^^^^^Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1 CSI-RS resources are configured for the UE, CSI-RS resources0, 1, … , ^^ − 1 are for a first TRP for a first time occasion to timeoccasion ^^ − 1 and CSI-RS resources ^^^^^^^^ + 0, ^^^^^^^^ + 1, … , ^^^^^^^^ + ^^ − 1 arefor a second TRP for the first time occasions to time occasion^^ − 1.

[0080] In a fourth example, the method of the first example, wherein ^^^^^^^^represents a number of TRPs with measurement resources and ^^ represents a number of CSI-reference signal (RS) resources for channel measurement at a TRP, and ^^ CSI-RS resource sets are configured for the UE, each CSI-RS resource set comprising ^^^^^^^^CSI-RS resources.

[0081] In a fifth example, the method of the fourth example, wherein a first CSI-RS resource set from the ^^ CSI-RS resource sets has a common slot offset with a second CSI-RS resource set from the ^^ CSI-RS resource sets.

[0082] In a sixth example, the method of the first example, wherein ^^^^^^^^represents a number of TRPs with measurement resources and ^^ represents a number of CSI-reference signal (RS) resources for channel measurement at a TRP, and ^^^^^^^^CSI-RS resource sets are configured for the UE, each CSI-RS resource set comprising ^^ CSI-RS resources.

[0083] In a seventh example, the method of the sixth example, wherein a first CSI-RS resource of a first CSI-RS resource set and a second CSI-RS resource of a second CSI-Rs resource set are associated with a same time occasion.Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1

[0084] In an eighth example, the method of the first example, wherein the Type-II codebook that jointly supports CSI feedback for mTRP CJT and CSI feedback with time domain compression includes ^^1, ^̃^2, ^^^^^^and ^^^^, and wherein ^^1represents spatial beam ^̃^2represents a combination coefficient forbitmap and quantization design, ^^^^^^represents FD basis selection and ^^^^represent doppler selection.

[0085] In a ninth example, the method of the eighth example, wherein the Type-II codebook that jointly supports CSI feedback for mTRP CJT and CSI feedback with time domain compression includes a first mode for independent frequency domain selection at a TRP and is based on a codebook structure of ^^1,1^̃^2,1(^^^^,1^^^^^,1) ^^ .

[0086] In a tenth example, the method of the eighth example, wherein the Type-II codebook that jointly supports CSI feedback for mTRP CJT and CSI feedback with time domain compression includes a second mode for common frequency domain component selection at all TRPs and is based on a codebook structure of ^^1,1^̃^2,1(^^^^^^^^^,1) ^^ .

[0087] In an eleventh example, the method of the first example, wherein the Type-II codebook that jointly supports CSI feedback for mTRP CJT and CSI feedback includes spatial domain basis selection, frequency domain component basis selection, doppler domain basis selection and coefficient subset selection, and wherein each of the spatial domain basis selection, theAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 frequency domain basis selection, the doppler domain basis selection and the coefficient subset selection includes a determination according to polarization, spatial layer and TRP.

[0088] In a twelfth example, the method of the eleventh example, wherein the polarization selection for the spatial domain basis selection is common for polarizations, the spatial domain basis selection is common for spatial layers and the spatial domain basis selection is independent across TRPs.

[0089] In a thirteenth example, the method of the eleventh example, wherein the frequency domain basis selection is common for polarizations, the frequency domain basis selection is independent across spatial layers and the frequency domain basis selection is independent across TRPs.

[0090] In a fourteenth example, the method of the eleventh example, wherein the frequency domain basis selection is common across polarizations, the frequency domain basis selection is independent across spatial layers and the frequency domain basis selection is common across TRPs.

[0091] In a fifteenth example, the method of the eleventh example, wherein the doppler domain basis selection is common across polarizations, the doppler domain basis selection is independent across spatial layers and the doppler domain basis selection is independent across TRPs.

[0092] In a sixteenth example, the method of the first example, wherein for a spatial layer ^^, a strongest coefficient among the mTRPs is indicated by the UE.Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1

[0093] In a seventeenth example, the method of the sixteenth example, wherein the strongest coefficient among the mTRPs is associated with (^^∗^^, ^^∗^^, ^^∗^^, ^^^∗^) where ^^∗represents a FD component index, ^^∗spatial beam index, ^^∗represents aselected TRP index and ^^^∗^ represents a doppler component index.

[0094] In an eighteenth example, the method of the seventeenth example, wherein the spatial beam index is within arange of [0, ^^ − 1].

[0095] In a nineteenth example, the method of the seventeenth example, wherein the spatial beam index is within a range ofrange of [0,2 ∙ ^^ − 1].

[0096] In a twentieth example, the method of the seventeenth example, wherein linear combination coefficients are configured into multiple groups and wherein the strongest coefficient is associated with one of the multiple groups.

[0097] In a twenty first example, the method of the twentieth example, wherein the combination coefficients are configured into multiple groups based on polarization and TRPs.

[0098] In a twenty second example, the method of the twentieth example, wherein the combination coefficients are configured into multiple groups based on polarization.

[0099] In a twenty third example, the method of the twentieth example, wherein nonzero coefficients are configured into multiple groups based on TRPs.Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1

[0100] In a twenty fourth example, the method of the sixteenth example, wherein the strongest coefficient among the mTRPs is associated with (^^∗^^, ^^∗^^, ^^∗^^, ^^^∗^) where ^^^∗^ is used as an indication of a selected TRP index at the spatial layer.

[0101] In a twenty fifth example, a processor configured to perform any of the methods of the first through twenty fourth examples.

[0102] In a twenty sixth example, a user equipment (UE) configured to perform any of the methods of the first through twenty fourth examples.

[0103] Those skilled in the art will understand that the above-described example embodiments may be implemented in any suitable software or hardware configuration or combination thereof. An example hardware platform for implementing the example embodiments may include, for example, an Intel x86 based platform with compatible operating system, a Windows OS, a Mac platform and MAC OS, a mobile device having an operating system such as iOS, Android, etc. The example embodiments described above may be embodied as a program containing lines of code stored on a non-transitory computer readable storage medium that, when compiled, may be executed on a processor or microprocessor.

[0104] Although this application described various embodiments each having different features in various combinations, those skilled in the art will understand that any of the features of one embodiment may be combined with the features of the other embodiments in any manner not specificallyAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 disclaimed or which is not functionally or logically inconsistent with the operation of the device or the stated functions of the disclosed embodiments.

[0105] It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled so as to minimize risks of unintentional or unauthorized access or use, and the nature of authorized use should be clearly indicated to users.

[0106] It will be apparent to those skilled in the art that various modifications may be made in the present disclosure, without departing from the spirit or the scope of the disclosure. Thus, it is intended that the present disclosure cover modifications and variations of this disclosure provided they come within the scope of the appended claims and their equivalent.

Claims

Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1 What is Claimed:

1. An apparatus comprising processing circuitry coupled to memory, the processing circuitry configured to: process, based on signaling received from a base station, configuration information for reporting channel state information (CSI) using a Type-II codebook that jointly supports CSI feedback for multiple transmission reception point (mTRP) coherent joint transmission (CJT) and CSI feedback with time domain compression; process, based on signaling received from the base station, CSI measurement resources; and generate, for transmission to the base station, Type-II codebook based CSI feedback to the base station.

2. The apparatus of claim 1, wherein ^^^^^^^^represents a number of TRPs with measurement resources and ^^ represents a number of CSI-reference signal (RS) resources for channel measurement at a TRP, and wherein ^^^^^^^^ × ^^ CSI-RS resources are configured for the UE,CSI-RS resources 0, 1, … , ^^^^^^^^ − 1 are for a first TRP to ^^^^^^^^ − 1 fora first time occasion and CSI-Rs resources 0 + ^^, 1 + ^^, … , ^^^^^^^^ − 1 + ^^are for the first TRP to ^^^^^^^^ − 1 for a second time occasion.

3. The apparatus of claim 1, wherein ^^^^^^^^represents a number of TRPs with measurement resources and ^^ represents a number of CSI-reference signal (RS) resources for channel measurement at a TRP, and wherein ^^ × ^^^^^^^^ CSI-RS resources are configured for the UE,CSI-RS resources 0, 1, … , ^^ − 1 are for a first TRP for a first timeoccasion to time^^ − 1 and CSI-RS resources ^^^^^^^^ + 0, ^^^^^^^^ +Attorney Docket No. 30134 / 89702 Ref. No. P64064WO11, … , ^^^^^^^^ + ^^ − 1 are for a second TRP for the first time occasionsto time occasion ^^ − 1.

4. The apparatus of claim 1, wherein ^^^^^^^^represents a number of TRPs with measurement resources and ^^ represents a number of CSI-reference signal (RS) resources for channel measurement at a TRP, and ^^ CSI-RS resource sets are configured for the UE, each CSI- RS resource set comprising ^^^^^^^^CSI-RS resources.

5. The apparatus of claim 4, wherein a first CSI-RS resource set from the ^^ CSI-RS resource sets has a common slot offset with a second CSI-RS resource set from the ^^ CSI-RS resource sets.

6. The apparatus of claim 1, wherein ^^^^^^^^represents a number of TRPs with measurement resources and ^^ represents a number of CSI-reference signal (RS) resources for channel measurement at a TRP, and ^^^^^^^^CSI-RS resource sets are configured for the UE, each CSI-RS resource set comprising ^^ CSI-RS resources.

7. The apparatus of claim 6, wherein a first CSI-RS resource of a first CSI-RS resource set and a second CSI-RS resource of a second CSI-Rs resource set are associated with a same time occasion.Attorney Docket No. 30134 / 89702 Ref. No. P64064WO1 8. The apparatus of claim 1, wherein the Type-II codebook that jointly supports CSI feedback for mTRP CJT and CSI feedback with time domain compression includes ^^1, ^̃^2, ^^^^^^and ^^^^, and wherein ^^1represents spatial beam ^̃^2representsa combination coefficient for bitmap and quantization design, ^^^^^^represents FD basis selection and ^^^^represent dopplerbasis selection.

9. The apparatus of claim 8, wherein the Type-II codebook that jointly supports CSI feedback for mTRP CJT and CSI feedback with time domain compression includes a first mode for independent frequency domain selection at a TRP and is based on a codebook ^^1,1^̃^2,1(^^^^,1< / sub>^^^^^,1) ^^ structure .<img src='' class="img-anchor img-center" img-id="IMGF000036_0003" / >10. The apparatus of claim 8, wherein the Type-II codebook that jointly supports CSI feedback for mTRP CJT and CSI feedback with time domain compression includes a second mode for common frequency domain component selection at all TRPs and is based on ^^1,1^̃^2,1(^^^^^^^^^,1) ^^ a codebook structure ].<img src='' class="img-anchor img-center" img-id="IMGF000036_0004" / >11. The apparatus of claim 1, wherein the Type-II codebook that jointly supports CSI feedback for mTRP CJT and CSI feedback includes spatial domain basis selection, frequency domain component basis selection, doppler domain basis selection and coefficient subset selection, and wherein each of the spatial domain basis selection, the frequency domain basis selection, the doppler domain basisAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 selection and the coefficient subset selection includes a determination according to polarization, spatial layer and TRP.

12. The apparatus of claim 11, wherein the polarization selection for the spatial domain basis selection is common for polarizations, the spatial domain basis selection is common for spatial layers and the spatial domain basis selection is independent across TRPs.

13. The apparatus of claim 11, wherein the frequency domain basis selection is common for polarizations, the frequency domain basis selection is independent across spatial layers and the frequency domain basis selection is independent across TRPs.

14. The apparatus of claim 11, wherein the frequency domain basis selection is common across polarizations, the frequency domain basis selection is independent across spatial layers and the frequency domain basis selection is common across TRPs.

15. The apparatus of claim 11, wherein the doppler domain basis selection is common across polarizations, the doppler domain basis selection is independent across spatial layers and the doppler domain basis selection is independent across TRPs.

16. The apparatus of claim 1, wherein for a spatial layer ^^, a strongest coefficient among the mTRPs is indicated by the UE.

17. The apparatus of claim 16, wherein the strongest coefficient among the mTRPs is associated with (^^∗^^, ^^∗^^, ^^∗^^, ^^^∗^) where ^^∗represents a FD component index, ^^∗represents a spatial beamAttorney Docket No. 30134 / 89702 Ref. No. P64064WO1 index, ^^∗represents a selected TRP index and ^^∗ ^^represents a doppler component index.

18. The apparatus of claim 16, wherein linear combination coefficients are configured into multiple groups and wherein the strongest coefficient is associated with one of the multiple groups.

19. The apparatus of claim 19, wherein the combination coefficients are configured into multiple groups based on one of (i) polarization and TRPs, or (ii) polarization.

20. The apparatus of claim 16, wherein the strongest coefficient among the mTRPs is associated with (^^∗^^, ^^∗^^, ^^∗^^, ^^^∗^) where ^^^∗^ is used as an indication of a selected TRP index at the spatial layer.

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