REPORTING COHERENT JOINT TRANSMISSION TYPE II CHANNEL STATE INFORMATION FEEDBACK

Abstract

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive one or more reference signals from a plurality of transmit receive points (TRPs) associated with a network entity. The UE may transmit, to the network entity and based at least in part on the one or more reference signals, a coherent joint transmission (CJT) Type II channel state information (CSI) feedback report. The CJT Type II CSI feedback report may be based at least in part on a two-stage frequency domain (FD) basis reporting irrespective of a quantity of precoding matrix indicator (PMI) subbands. The CJT Type II CSI feedback report may be based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients. Numerous other aspects are described.

Description

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for reporting coherent joint transmission (CJT) Type II channel state information (CSI) feedback.

BACKGROUND

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, or the like). Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE). LTE/LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP).

A wireless network may include one or more base stations that support communication for a user equipment (UE) or multiple UEs. A UE may communicate with a base station via downlink communications and uplink communications. “Downlink” (or “DL”) refers to a communication link from the base station to the UE, and “uplink” (or “UL”) refers to a communication link from the UE to the base station.

The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different UEs to communicate on a municipal, national, regional, and/or global level. New Radio (NR), which may be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the 3GPP. NR is designed to better support mobile broadband internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink, using CP-OFDM and/or single-carrier frequency division multiplexing (SC-FDM) (also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) on the uplink, as well as supporting beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. As the demand for mobile broadband access continues to increase, further improvements in LTE, NR, and other radio access technologies remain useful.

SUMMARY

In some implementations, an apparatus for wireless communication at a user equipment (UE) includes a memory and one or more processors, coupled to the memory, configured to: receive one or more reference signals from a plurality of transmit receive points (TRPs) associated with a network entity; and transmit, to the network entity and based at least in part on the one or more reference signals, a coherent joint transmission (CJT) Type II channel state information (CSI) feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage frequency domain (FD) basis reporting irrespective of a quantity of precoding matrix indicator (PMI) subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

In some implementations, an apparatus for wireless communication at a network entity includes a memory and one or more processors, coupled to the memory, configured to: transmit, to a UE and via a plurality of TRPs associated with the network entity, one or more reference signals; and receive, from the UE and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

In some implementations, a method of wireless communication performed by a UE includes receiving one or more reference signals from a plurality of TRPs associated with a network entity; and transmitting, to the network entity and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

In some implementations, a method of wireless communication performed by a network entity includes transmitting, to a UE and via a plurality of TRPs associated with the network entity, one or more reference signals; and receiving, from the UE and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

In some implementations, a non-transitory computer-readable medium storing a set of instructions for wireless communication includes one or more instructions that, when executed by one or more processors of a UE, cause the UE to: receive one or more reference signals from a plurality of TRPs associated with a network entity; and transmit, to the network entity and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

In some implementations, a non-transitory computer-readable medium storing a set of instructions for wireless communication includes one or more instructions that, when executed by one or more processors of a network entity, cause the network entity to: transmit, to a UE and via a plurality of TRPs associated with the network entity, one or more reference signals; and receive, from the UE and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

In some implementations, an apparatus for wireless communication includes means for receiving one or more reference signals from a plurality of TRPs associated with a network entity; and means for transmitting, to the network entity and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

In some implementations, an apparatus for wireless communication includes means for transmitting, to a UE and via a plurality of TRPs associated with the apparatus, one or more reference signals; and means for receiving, from the UE and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

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

The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages, will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purposes of illustration and description, and not as a definition of the limits of the claims.

While aspects are described in the present disclosure by illustration to some examples, those skilled in the art will understand that such aspects may be implemented in many different arrangements and scenarios. Techniques described herein may be implemented using different platform types, devices, systems, shapes, sizes, and/or packaging arrangements. For example, some aspects may be implemented via integrated chip embodiments or other non-module-component based devices (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail/purchasing devices, medical devices, and/or artificial intelligence devices). Aspects may be implemented in chip-level components, modular components, non-modular components, non-chip-level components, device-level components, and/or system-level components. Devices incorporating described aspects and features may include additional components and features for implementation and practice of claimed and described aspects. For example, transmission and reception of wireless signals may include one or more components for analog and digital purposes (e.g., hardware components including antennas, radio frequency (RF) chains, power amplifiers, modulators, buffers, processors, interleavers, adders, and/or summers). It is intended that aspects described herein may be practiced in a wide variety of devices, components, systems, distributed arrangements, and/or end-user devices of varying size, shape, and constitution.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects. The same reference numbers in different drawings may identify the same or similar elements.

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

FIG. 2 is a diagram illustrating an example of a base station in communication with a user equipment (UE) in a wireless network, in accordance with the present disclosure.

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

FIG. 4 is a diagram illustrating an example of enhanced Type 2 (eType II) channel state information (CSI) feedback, in accordance with the present disclosure.

FIG. 5 is a diagram illustrating an example of coherent joint transmission (CJT) Type II CSI feedback, in accordance with the present disclosure.

FIGS. 6-7 are diagrams illustrating examples associated with reporting CJT Type II CSI feedback, in accordance with the present disclosure.

FIGS. 8-9 are diagrams illustrating example processes associated with reporting CJT Type II CSI feedback, in accordance with the present disclosure.

FIGS. 10-11 are diagrams of example apparatuses for wireless communication, in accordance with the present disclosure.

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully hereinafter with reference to the accompanying drawings. This disclosure may, however, be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. One skilled in the art should appreciate that the scope of the disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of or combined with any other aspect of the disclosure. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method which is practiced using other structure, functionality, or structure and functionality in addition to or other than the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim.

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

While aspects may be described herein using terminology commonly associated with a 5G or New Radio (NR) radio access technology (RAT), aspects of the present disclosure can be applied to other RATs, such as a 3G RAT, a 4G RAT, and/or a RAT subsequent to 5G (e.g., 6G).

FIG. 1 is a diagram illustrating an example of a wireless network 100, in accordance with the present disclosure. The wireless network 100 may be or may include elements of a 5G (e.g., NR) network and/or a 4G (e.g., Long Term Evolution (LTE)) network, among other examples. The wireless network 100 may include one or more base stations 110 (shown as a BS 110a, a BS 110b, a BS 110c, and a BS 110d), a user equipment (UE) 120 or multiple UEs 120 (shown as a UE 120a, a UE 120b, a UE 120c, a UE 120d, and a UE 120e), and/or other network entities. A base station 110 is an entity that communicates with UEs 120. A base station 110 (sometimes referred to as a BS) may include, for example, an NR base station, an LTE base station, a Node B, an eNB (e.g., in 4G), a gNB (e.g., in 5G), an access point, and/or a transmit receive point (TRP). Each base station 110 may provide communication coverage for a particular geographic area. In the Third Generation Partnership Project (3GPP), the term “cell” can refer to a coverage area of a base station 110 and/or a base station subsystem serving this coverage area, depending on the context in which the term is used.

A base station 110 may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another type of cell. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs 120 with service subscriptions. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs 120 with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs 120 having association with the femto cell (e.g., UEs 120 in a closed subscriber group (CSG)). A base station 110 for a macro cell may be referred to as a macro base station. A base station 110 for a pico cell may be referred to as a pico base station. A base station 110 for a femto cell may be referred to as a femto base station or an in-home base station. In the example shown in FIG. 1, the BS 110a may be a macro base station for a macro cell 102a, the BS 110b may be a pico base station for a pico cell 102b, and the BS 110c may be a femto base station for a femto cell 102c. A base station may support one or multiple (e.g., three) cells.

In some aspects, the term “base station” (e.g., the base station 110) or “network entity” may refer to an aggregated base station, a disaggregated base station, an integrated access and backhaul (IAB) node, a relay node, and/or one or more components thereof. For example, in some aspects, “base station” or “network entity” may refer to a central unit (CU), a distributed unit (DU), a radio unit (RU), a Near-Real Time (Near-RT) RAN Intelligent Controller (RIC), or a Non-Real Time (Non-RT) RIC, or a combination thereof. In some aspects, the term “base station” or “network entity” may refer to one device configured to perform one or more functions, such as those described herein in connection with the base station 110. In some aspects, the term “base station” or “network entity” may refer to a plurality of devices configured to perform the one or more functions. For example, in some distributed systems, each of a number of different devices (which may be located in the same geographic location or in different geographic locations) may be configured to perform at least a portion of a function, or to duplicate performance of at least a portion of the function, and the term “base station” or “network entity” may refer to any one or more of those different devices. In some aspects, the term “base station” or “network entity” may refer to one or more virtual base stations and/or one or more virtual base station functions. For example, in some aspects, two or more base station functions may be instantiated on a single device. In some aspects, the term “base station” or “network entity” may refer to one of the base station functions and not another. In this way, a single device may include more than one base station.

In some examples, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a base station 110 that is mobile (e.g., a mobile base station). In some examples, the base stations 110 may be interconnected to one another and/or to one or more other base stations 110 or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces, such as a direct physical connection or a virtual network, using any suitable transport network.

The wireless network 100 may include one or more relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a base station 110 or a UE 120) and send a transmission of the data to a downstream station (e.g., a UE 120 or a base station 110). A relay station may be a UE 120 that can relay transmissions for other UEs 120. In the example shown in FIG. 1, the BS 110d (e.g., a relay base station) may communicate with the BS 110a (e.g., a macro base station) and the UE 120d in order to facilitate communication between the BS 110a and the UE 120d. A base station 110 that relays communications may be referred to as a relay station, a relay base station, a relay, or the like.

The wireless network 100 may be a heterogeneous network that includes base stations 110 of different types, such as macro base stations, pico base stations, femto base stations, relay base stations, or the like. These different types of base stations 110 may have different transmit power levels, different coverage areas, and/or different impacts on interference in the wireless network 100. For example, macro base stations may have a high transmit power level (e.g., 5 to 40 watts) whereas pico base stations, femto base stations, and relay base stations may have lower transmit power levels (e.g., 0.1 to 2 watts).

A network controller 130 may couple to or communicate with a set of base stations 110 and may provide coordination and control for these base stations 110. The network controller 130 may communicate with the base stations 110 via a backhaul communication link. The base stations 110 may communicate with one another directly or indirectly via a wireless or wireline backhaul communication link.

The UEs 120 may be dispersed throughout the wireless network 100, and each UE 120 may be stationary or mobile. A UE 120 may include, for example, an access terminal, a terminal, a mobile station, and/or a subscriber unit. A UE 120 may be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device, a biometric device, a wearable device (e.g., a smart watch, smart clothing, smart glasses, a smart wristband, smart jewelry (e.g., a smart ring or a smart bracelet)), an entertainment device (e.g., a music device, a video device, and/or a satellite radio), a vehicular component or sensor, a smart meter/sensor, industrial manufacturing equipment, a global positioning system device, and/or any other suitable device that is configured to communicate via a wireless medium.

Some UEs 120 may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. An MTC UE and/or an eMTC UE may include, for example, a robot, a drone, a remote device, a sensor, a meter, a monitor, and/or a location tag, that may communicate with a base station, another device (e.g., a remote device), or some other entity. Some UEs 120 may be considered Internet-of-Things (IoT) devices, and/or may be implemented as NB-IoT (narrowband IoT) devices. Some UEs 120 may be considered a Customer Premises Equipment. A UE 120 may be included inside a housing that houses components of the UE 120, such as processor components and/or memory components. In some examples, the processor components and the memory components may be coupled together. For example, the processor components (e.g., one or more processors) and the memory components (e.g., a memory) may be operatively coupled, communicatively coupled, electronically coupled, and/or electrically coupled.

In general, any number of wireless networks 100 may be deployed in a given geographic area. Each wireless network 100 may support a particular RAT and may operate on one or more frequencies. A RAT may be referred to as a radio technology, an air interface, or the like. A frequency may be referred to as a carrier, a frequency channel, or the like. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

In some examples, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may communicate directly using one or more sidelink channels (e.g., without using a base station 110 as an intermediary to communicate with one another). For example, the UEs 120 may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, or a vehicle-to-pedestrian (V2P) protocol), and/or a mesh network. In such examples, a UE 120 may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by the base station 110.

Devices of the wireless network 100 may communicate using the electromagnetic spectrum, which may be subdivided by frequency or wavelength into various classes, bands, channels, or the like. For example, devices of the wireless network 100 may communicate using one or more operating bands. In 5G NR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz-7.125 GHz) and FR2 (24.25 GHz-52.6 GHz). It should be understood that although a portion of FR1 is greater than 6 GHZ, FR1 is often referred to (interchangeably) as a “Sub-6 GHz” band in various documents and articles. A similar nomenclature issue sometimes occurs with regard to FR2, which is often referred to (interchangeably) as a “millimeter wave” band in documents and articles, despite being different from the extremely high frequency (EHF) band (30 GHz-300 GHz) which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band.

The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Recent 5G NR studies have identified an operating band for these mid-band frequencies as frequency range designation FR3 (7.125 GHZ-24.25 GHZ). Frequency bands falling within FR3 may inherit FR1 characteristics and/or FR2 characteristics, and thus may effectively extend features of FR1 and/or FR2 into mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operation beyond 52.6 GHz. For example, three higher operating bands have been identified as frequency range designations FR4a or FR4-1 (52.6 GHz-71 GHz), FR4 (52.6 GHz-114.25 GHZ), and FR5 (114.25 GHZ-300 GHz). Each of these higher frequency bands falls within the EHF band.

With the above examples in mind, unless specifically stated otherwise, it should be understood that the term “sub-6 GHz” or the like, if used herein, may broadly represent frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. Further, unless specifically stated otherwise, it should be understood that the term “millimeter wave” or the like, if used herein, may broadly represent frequencies that may include mid-band frequencies, may be within FR2, FR4, FR4-a or FR4-1, and/or FR5, or may be within the EHF band. It is contemplated that the frequencies included in these operating bands (e.g., FR1, FR2, FR3, FR4, FR4-a, FR4-1, and/or FR5) may be modified, and techniques described herein are applicable to those modified frequency ranges.

In some aspects, a UE (e.g., UE 120) may include a communication manager 140. As described in more detail elsewhere herein, the communication manager 140 may receive one or more reference signals from a plurality of TRPs associated with a network entity; and transmit, to the network entity and based at least in part on the one or more reference signals, a coherent joint transmission (CJT) Type II channel state information (CSI) feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage frequency domain (FD) basis reporting irrespective of a quantity of precoding matrix indicator (PMI) subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients. Additionally, or alternatively, the communication manager 140 may perform one or more other operations described herein.

In some aspects, a network entity (e.g., base station 110) may include a communication manager 150. As described in more detail elsewhere herein, the communication manager 150 may transmit, to a UE and via a plurality of TRPs associated with the network entity, one or more reference signals; and receive, from the UE and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients. Additionally, or alternatively, the communication manager 150 may perform one or more other operations described herein.

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

FIG. 2 is a diagram illustrating an example 200 of a base station 110 in communication with a UE 120 in a wireless network 100, in accordance with the present disclosure. The base station 110 may be equipped with a set of antennas 234a through 234t, such as T antennas (T≥1). The UE 120 may be equipped with a set of antennas 252a through 252r, such as R antennas (R≥1).

At the base station 110, a transmit processor 220 may receive data, from a data source 212, intended for the UE 120 (or a set of UEs 120). The transmit processor 220 may select one or more modulation and coding schemes (MCSs) for the UE 120 based at least in part on one or more channel quality indicators (CQIs) received from that UE 120. The base station 110 may process (e.g., encode and modulate) the data for the UE 120 based at least in part on the MCS(s) selected for the UE 120 and may provide data symbols for the UE 120. The transmit processor 220 may process system information (e.g., for semi-static resource partitioning information (SRPI)) and control information (e.g., CQI requests, grants, and/or upper layer signaling) and provide overhead symbols and control symbols. The transmit processor 220 may generate reference symbols for reference signals (e.g., a cell-specific reference signal (CRS) or a demodulation reference signal (DMRS)) and synchronization signals (e.g., a primary synchronization signal (PSS) or a secondary synchronization signal (SSS)). A transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide a set of output symbol streams (e.g., T output symbol streams) to a corresponding set of modems 232 (e.g., T modems), shown as modems 232a through 232t. For example, each output symbol stream may be provided to a modulator component (shown as MOD) of a modem 232. Each modem 232 may use a respective modulator component to process a respective output symbol stream (e.g., for OFDM) to obtain an output sample stream. Each modem 232 may further use a respective modulator component to process (e.g., convert to analog, amplify, filter, and/or upconvert) the output sample stream to obtain a downlink signal. The modems 232a through 232t may transmit a set of downlink signals (e.g., T downlink signals) via a corresponding set of antennas 234 (e.g., T antennas), shown as antennas 234a through 234t.

At the UE 120, a set of antennas 252 (shown as antennas 252a through 252r) may receive the downlink signals from the base station 110 and/or other base stations 110 and may provide a set of received signals (e.g., R received signals) to a set of modems 254 (e.g., R modems), shown as modems 254a through 254r. For example, each received signal may be provided to a demodulator component (shown as DEMOD) of a modem 254. Each modem 254 may use a respective demodulator component to condition (e.g., filter, amplify, downconvert, and/or digitize) a received signal to obtain input samples. Each modem 254 may use a demodulator component to further process the input samples (e.g., for OFDM) to obtain received symbols. A MIMO detector 256 may obtain received symbols from the modems 254, may perform MIMO detection on the received symbols if applicable, and may provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, may provide decoded data for the UE 120 to a data sink 260, and may provide decoded control information and system information to a controller/processor 280. The term “controller/processor” may refer to one or more controllers, one or more processors, or a combination thereof. A channel processor may determine a reference signal received power (RSRP) parameter, a received signal strength indicator (RSSI) parameter, a reference signal received quality (RSRQ) parameter, and/or a CQI parameter, among other examples. In some examples, one or more components of the UE 120 may be included in a housing 284.

The network controller 130 may include a communication unit 294, a controller/processor 290, and a memory 292. The network controller 130 may include, for example, one or more devices in a core network. The network controller 130 may communicate with the base station 110 via the communication unit 294.

One or more antennas (e.g., antennas 234a through 234t and/or antennas 252a through 252r) may include, or may be included within, one or more antenna panels, one or more antenna groups, one or more sets of antenna elements, and/or one or more antenna arrays, among other examples. An antenna panel, an antenna group, a set of antenna elements, and/or an antenna array may include one or more antenna elements (within a single housing or multiple housings), a set of coplanar antenna elements, a set of non-coplanar antenna elements, and/or one or more antenna elements coupled to one or more transmission and/or reception components, such as one or more components of FIG. 2.

On the uplink, at the UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information (e.g., for reports that include RSRP, RSSI, RSRQ, and/or CQI) from the controller/processor 280. The transmit processor 264 may generate reference symbols for one or more reference signals. The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by the modems 254 (e.g., for DFT-s-OFDM or CP-OFDM), and transmitted to the base station 110. In some examples, the modem 254 of the UE 120 may include a modulator and a demodulator. In some examples, the UE 120 includes a transceiver. The transceiver may include any combination of the antenna(s) 252, the modem(s) 254, the MIMO detector 256, the receive processor 258, the transmit processor 264, and/or the TX MIMO processor 266. The transceiver may be used by a processor (e.g., the controller/processor 280) and the memory 282 to perform aspects of any of the methods described herein (e.g., with reference to FIGS. 6-11).

At the base station 110, the uplink signals from UE 120 and/or other UEs may be received by the antennas 234, processed by the modem 232 (e.g., a demodulator component, shown as DEMOD, of the modem 232), detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by the UE 120. The receive processor 238 may provide the decoded data to a data sink 239 and provide the decoded control information to the controller/processor 240. The base station 110 may include a communication unit 244 and may communicate with the network controller 130 via the communication unit 244. The base station 110 may include a scheduler 246 to schedule one or more UEs 120 for downlink and/or uplink communications. In some examples, the modem 232 of the base station 110 may include a modulator and a demodulator. In some examples, the base station 110 includes a transceiver. The transceiver may include any combination of the antenna(s) 234, the modem(s) 232, the MIMO detector 236, the receive processor 238, the transmit processor 220, and/or the TX MIMO processor 230. The transceiver may be used by a processor (e.g., the controller/processor 240) and the memory 242 to perform aspects of any of the methods described herein (e.g., with reference to FIGS. 6-11).

The controller/processor 240 of the base station 110, the controller/processor 280 of the UE 120, and/or any other component(s) of FIG. 2 may perform one or more techniques associated with reporting CJT Type II CSI feedback, as described in more detail elsewhere herein. For example, the controller/processor 240 of the base station 110, the controller/processor 280 of the UE 120, and/or any other component(s) of FIG. 2 may perform or direct operations of, for example, process 800 of FIG. 8, process 900 of FIG. 9, and/or other processes as described herein. The memory 242 and the memory 282 may store data and program codes for the base station 110 and the UE 120, respectively. In some examples, the memory 242 and/or the memory 282 may include a non-transitory computer-readable medium storing one or more instructions (e.g., code and/or program code) for wireless communication. For example, the one or more instructions, when executed (e.g., directly, or after compiling, converting, and/or interpreting) by one or more processors of the base station 110 and/or the UE 120, may cause the one or more processors, the UE 120, and/or the base station 110 to perform or direct operations of, for example, process 800 of FIG. 8, process 900 of FIG. 9, and/or other processes as described herein. In some examples, executing instructions may include running the instructions, converting the instructions, compiling the instructions, and/or interpreting the instructions, among other examples.

In some aspects, a UE (e.g., UE 120) includes means for receiving one or more reference signals from a plurality of TRPs associated with a network entity; and/or means for transmitting, to the network entity and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients. The means for the UE to perform operations described herein may include, for example, one or more of communication manager 140, antenna 252, modem 254, MIMO detector 256, receive processor 258, transmit processor 264, TX MIMO processor 266, controller/processor 280, or memory 282.

In some aspects, a network entity (e.g., base station 110) includes means for transmitting, to a UE and via a plurality of TRPs associated with the network entity, one or more reference signals; and/or means for receiving, from the UE and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients. In some aspects, the means for the network entity to perform operations described herein may include, for example, one or more of communication manager 150, transmit processor 220, TX MIMO processor 230, modem 232, antenna 234, MIMO detector 236, receive processor 238, controller/processor 240, memory 242, or scheduler 246.

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

As indicated above, FIG. 2 is provided as an example. Other examples may differ from what is described with regard to FIG. 2.

FIG. 3 is a diagram illustrating an example 300 of a disaggregated base station architecture, in accordance with the present disclosure.

Deployment of communication systems, such as 5G NR systems, may be arranged in multiple manners with various components or constituent parts. In a 5G NR system, or network, a network node, a network entity, a mobility element of a network, a RAN node, a core network node, a network element, or a network equipment, such as a base station (BS, e.g., base station 110), or one or more units (or one or more components) performing base station functionality, may be implemented in an aggregated or disaggregated architecture. For example, a BS (such as a Node B (NB), eNB, NR BS, 5G NB, access point (AP), a TRP, a cell, or the like) may be implemented as an aggregated base station (also known as a standalone BS or a monolithic BS) or a disaggregated base station.

An aggregated base station may be configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node. A disaggregated base station may be configured to utilize a protocol stack that is physically or logically distributed among two or more units (such as one or more CUs, one or more DUs, or one or more RUs). In some aspects, a CU may be implemented within a RAN node, and one or more DUs may be co-located with the CU, or alternatively, may be geographically or virtually distributed throughout one or multiple other RAN nodes. The DUs may be implemented to communicate with one or more RUs. Each of the CU, DU, and RU also can be implemented as virtual units (e.g., a virtual centralized unit (VCU), a virtual distributed unit (VDU), or a virtual radio unit (VRU)).

Base station-type operation or network design may consider aggregation characteristics of base station functionality. For example, disaggregated base stations may be utilized in an IAB network, an O-RAN (such as the network configuration sponsored by the O-RAN Alliance), or a virtualized radio access network (vRAN, also known as a cloud radio access network (C-RAN)). Disaggregation may include distributing functionality across two or more units at various physical locations, as well as distributing functionality for at least one unit virtually, which can enable flexibility in network design. The various units of the disaggregated base station, or disaggregated RAN architecture, can be configured for wired or wireless communication with at least one other unit.

The disaggregated base station architecture shown in FIG. 3 may include one or more CUs 310 that can communicate directly with a core network 320 via a backhaul link, or indirectly with the core network 320 through one or more disaggregated base station units (such as a Near-RT RIC 325 via an E2 link, or a Non-RT RIC 315 associated with a Service Management and Orchestration (SMO) Framework 305, or both). A CU 310 may communicate with one or more DUs 330 via respective midhaul links, such as an F1 interface. The DUs 330 may communicate with one or more RUs 340 via respective fronthaul links. The RUs 340 may communicate with respective UEs 120 via one or more radio frequency (RF) access links. In some implementations, the UE 120 may be simultaneously served by multiple RUs 340.

Each of the units (e.g., the CUS 310, the DUs 330, the RUs 340), as well as the Near-RT RICs 325, the Non-RT RICs 315, and the SMO Framework 305, may include one or more interfaces or be coupled to one or more interfaces configured to receive or transmit signals, data, or information (collectively, signals) via a wired or wireless transmission medium. Each of the units, or an associated processor or controller providing instructions to the communication interfaces of the units, can be configured to communicate with one or more of the other units via the transmission medium. For example, the units can include a wired interface configured to receive or transmit signals over a wired transmission medium to one or more of the other units. Additionally, the units can include a wireless interface, which may include a receiver, a transmitter or transceiver (such as an RF transceiver), configured to receive or transmit signals, or both, over a wireless transmission medium to one or more of the other units.

In some aspects, the CU 310 may host one or more higher layer control functions. Such control functions can include radio resource control (RRC), packet data convergence protocol (PDCP), service data adaptation protocol (SDAP), or the like. Each control function can be implemented with an interface configured to communicate signals with other control functions hosted by the CU 310. The CU 310 may be configured to handle user plane functionality (e.g., Central Unit-User Plane (CU-UP)), control plane functionality (e.g., Central Unit-Control Plane (CU-CP)), or a combination thereof. In some implementations, the CU 310 can be logically split into one or more CU-UP units and one or more CU-CP units. The CU-UP unit can communicate bidirectionally with the CU-CP unit via an interface, such as the E1 interface when implemented in an O-RAN configuration. The CU 310 can be implemented to communicate with the DU 330, as necessary, for network control and signaling.

The DU 330 may correspond to a logical unit that includes one or more base station functions to control the operation of one or more RUs 340. In some aspects, the DU 330 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation and demodulation, or the like) depending, at least in part, on a functional split, such as those defined by the 3GPP. In some aspects, the DU 330 may further host one or more low-PHY layers. Each layer (or module) can be implemented with an interface configured to communicate signals with other layers (and modules) hosted by the DU 330, or with the control functions hosted by the CU 310.

Lower-layer functionality can be implemented by one or more RUs 340. In some deployments, an RU 340, controlled by a DU 330, may correspond to a logical node that hosts RF processing functions, or low-PHY layer functions (such as performing fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, physical random access channel (PRACH) extraction and filtering, or the like), or both, based at least in part on the functional split, such as a lower layer functional split. In such an architecture, the RU(s) 340 can be implemented to handle over the air (OTA) communication with one or more UEs 120. In some implementations, real-time and non-real-time aspects of control and user plane communication with the RU(s) 340 can be controlled by the corresponding DU 330. In some scenarios, this configuration can enable the DU(s) 330 and the CU 310 to be implemented in a cloud-based RAN architecture, such as a vRAN architecture.

The SMO Framework 305 may be configured to support RAN deployment and provisioning of non-virtualized and virtualized network elements. For non-virtualized network elements, the SMO Framework 305 may be configured to support the deployment of dedicated physical resources for RAN coverage requirements which may be managed via an operations and maintenance interface (such as an O1 interface). For virtualized network elements, the SMO Framework 305 may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud) 390) to perform network element life cycle management (such as to instantiate virtualized network elements) via a cloud computing platform interface (such as an O2 interface). Such virtualized network elements can include, but are not limited to, CUs 310, DUs 330, RUs 340 and Near-RT RICs 325. In some implementations, the SMO Framework 305 can communicate with a hardware aspect of a 4G RAN, such as an open eNB (O-eNB) 311, via an O1 interface. Additionally, in some implementations, the SMO Framework 305 can communicate directly with one or more RUs 340 via an O1 interface. The SMO Framework 305 also may include a Non-RT RIC 315 configured to support functionality of the SMO Framework 305.

The Non-RT RIC 315 may be configured to include a logical function that enables non-real-time control and optimization of RAN elements and resources, Artificial Intelligence/Machine Learning (AI/ML) workflows including model training and updates, or policy-based guidance of applications/features in the Near-RT RIC 325. The Non-RT RIC 315 may be coupled to or communicate with (such as via an A1 interface) the Near-RT RIC 325. The Near-RT RIC 325 may be configured to include a logical function that enables near-real-time control and optimization of RAN elements and resources via data collection and actions over an interface (such as via an E2 interface) connecting one or more CUs 310, one or more DUs 330, or both, as well as an O-eNB, with the Near-RT RIC 325.

In some implementations, to generate AI/ML models to be deployed in the Near-RT RIC 325, the Non-RT RIC 315 may receive parameters or external enrichment information from external servers. Such information may be utilized by the Near-RT RIC 325 and may be received at the SMO Framework 305 or the Non-RT RIC 315 from non-network data sources or from network functions. In some examples, the Non-RT RIC 315 or the Near-RT RIC 325 may be configured to tune RAN behavior or performance. For example, the Non-RT RIC 315 may monitor long-term trends and patterns for performance and employ AI/ML models to perform corrective actions through the SMO Framework 305 (such as reconfiguration via 01) or via creation of RAN management policies (such as A1 policies).

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

A UE may transmit enhanced Type 2 (eType II) CSI feedback based at least in part on a spatial domain (SD) compression and a frequency domain (FD) compression via a linear combination of discrete Fourier transform (DFT) bases. The eType II CSI feedback may be a Release 16 eType II CSI feedback. The UE may transmit the eType II CSI feedback for a single TRP. The eType II CSI feedback may be based at least in part on a codebook structure, in which precoders for a layer l across N₃ precoding matrix indicator (PMI) subbands may be given by size-N_t×N₃ matrix W^(l)=W_l{tilde over (W)}_2,lW_f,l^H, where N_t and N₃ are integer values. An SD basis W₁ (DFT bases) may be layer-common, and the UE may select L beams, where L may be radio resource control (RRC) configured. An FD basis W_f,l^H (DFT bases) may be layer-specific, and the UE may select M bases out of candidate N₃ bases and report the selection for each layer. For coefficients {tilde over (W)}_2,l, for each layer, the UE may report up to (non-zero) K₀ coefficients, where K₀ may be RRC configured. Across a plurality of layers (e.g., all layers), the UE may report up to (non-zero) 2K₀ coefficients. The UE may set to zero unreported coefficients. The UE may report a coefficient selection (e.g., a location of non-zero coefficients (NZCs) within {tilde over (W)}_2,l) and a quantization of the NZCs for each layer.

FIG. 4 is a diagram illustrating an example 400 of eType II CSI feedback, in accordance with the present disclosure.

As shown in FIG. 4, for a channel H, which may be associated with an N_t×N₃ matrix, a UE may perform an SD compression, which may result in W₁, which may be an N_t×2L matrix. The UE may determine SD coefficients based at least in part on W₂=W₁^HH. The UE may perform an FD compression, which may result in W_f, which may be an N₃×M matrix. The UE may determine (SD, FD) coefficients based at least in part on {tilde over (W)}₂=W₂W_f. In other words, the UE may determine SD coefficients and FD coefficients based at least in part on {tilde over (W)}₂=W₂W_f. The UE may perform a coefficient compression, in which the UE may select strongest coefficients and set weakest coefficients to zero, which may result in a precoder in accordance with W=W₁{tilde over (W)}₂W_f^H. The precoder may be used to form a codebook structure, which may be used by the UE when transmitting eType II CSI feedback.

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

A network entity may transmit data to UE using CJT across multiple TRPs (mTRP), which may improve coverage and an average throughput with high performance backhaul and synchronization. The UE may transmit CJT Type II CSI feedback which may be based at least in part on a codebook structure. In a first option, the codebook structure may be based at least in part on a joint FD compression across TRPs. A precoder (P) for CJT across two TRPs may be given by:

$P=\left[\begin{array}{c}{P}_1\\ P_2\end{array}\right]=\left[\begin{array}{cc}{W}_{1,1}& 0\\ 0& W_{1,2}\end{array}\right]{\tilde{W}}_2{W}_f^H,$

where P₁ and P₂ are TRP-specific Type II precoders, and W_1,1 and W_1,2 are SD compression matrices for a first TRP and a second TRP, respectively.

In a second option, the codebook structure may be based at least in part on a per-TRP FD compression and co-amplitude/phase across TRPs. A precoder (P) for CJT across two TRPs may be given by:

$P=\left[\begin{array}{c}{P}_1\\ {\mathrm{qP}}_2\end{array}\right]=\left[\begin{array}{c}{W}_{1,1}{\tilde{W}}_{2,1}{W}_{f,1}^H\\ {\mathrm{qW}}_{1,2}{\tilde{W}}_{2,2}{W}_{f,2}^H\end{array}\right],$

where P₁ and P₂ are TRP-specific Type II precoders, and q is an inter-TRP co-amplitude/phase.

FIG. 5 is a diagram illustrating an example 500 of CJT Type II CSI feedback, in accordance with the present disclosure.

As shown in FIG. 5, for a first TRP, a channel H₁ may be associated with an N_t×N₃ matrix. A UE may perform an SD compression, which may result in W_1,1, which may be an N_t×2L matrix. The UE may determine SD coefficients based at least in part on W_2,1=W_1,1^HH₁. The UE may perform an FD compression, which may result in W_f,1, which may be an N₃×M matrix. The UE may determine (SD, FD) coefficients based at least in part on {tilde over (W)}_2,1=W_2,1W_f,1. For a second TRP, a channel H₂ may be associated with an N_t×N₃ matrix. The UE may perform an SD compression, which may result in W_1,2, which may be an N_t×2L matrix. The UE may determine SD coefficients based at least in part on W_2,2=W_1,2^HH₂. The UE may perform an FD compression, which may result in W_f,2, which may be an N₃×M matrix. The UE may determine (SD, FD) coefficients based at least in part on {tilde over (W)}_2,2=W_2,2W_f,2. An inter-TRP co-amplitude/phase (q) may be based at least in part on the (SD, FD) coefficients for the first TRP, which may be associated with W_2,1=W_1,1^HH₁, and the (SD, FD) coefficients for the second TRP, which may be associated with {tilde over (W)}_2,2=W_2,2W_f,2. The UE may perform a joint coefficient compression based at least in part on the (SD, FD) coefficients for the first TRP and the (SD, FD) coefficients for the second TRP. The UE may perform the joint coefficient compression, in which the UE may select strongest coefficients and set weakest coefficients to zero, which may result in a precoder in accordance with:

$P=\left[\begin{array}{c}{P}_1\\ {\mathrm{qP}}_2\end{array}\right]=\left[\begin{array}{c}{W}_{1,1}{\tilde{W}}_{2,1}{W}_{f,1}^H\\ {\mathrm{qW}}_{1,2}{\tilde{W}}_{2,2}{W}_{f,2}^H\end{array}\right],$

where the precoder may be used to form a codebook structure, which may be used by the UE when transmitting CJT Type II CSI feedback.

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

For CJT Type II CSI feedback with a TRP-specific Type II precoder (e.g., the second option, as described above), independent FD basis selection may be used for each TRP, and a UE may report an FD basis selection separately for each TRP. For eType II CSI feedback, FD basis selection may be dependent on a quantity of PMI subbands N₃. For example, the UE may use a single stage FD basis report for N₃≤19, or the UE may use a two-stage FD basis report for N₃>19. For N₃≤19, the UE may signal M−1 FD bases from N₃−1 candidate FD bases via

$\lceil {\log }_2\left(\begin{array}{c}{N}_3-1\\ M-1\end{array}\right)\rceil$

(for each layer). For N₃>19, the UE may first report a starting index for a window-based intermediate set (e.g., down select from N₃ to 2M) via ┌log₂ 2M┐ bits, and then the UE may report M−1 FD bases from 2M−1 candidate FD bases

$\lceil {\log }_2\left(\begin{array}{c}2M-1\\ M-1\end{array}\right)\rceil$

bits (for each layer). A simple extension of the eType II FD basis selection to CJT mTRP may imply that FD basis selection bits may be scaled based at least in part on the quantity of TRPs. For example, 48 bits for eType II FD basis selection may be increased to 48×4=192 bits for CJT across four TRPs (e.g., assuming N₃=19, M=5, and RI=4), where RI is a rank indicator.

For CJT Type II CSI feedback, the UE may report an NZC coefficient selection for each TRP (e.g., the location of NZCs within the (SD,FD) coefficient matrix {tilde over (W)}_2,TRP). For eType II CSI feedback, coefficient selection may be an RI size 2LM bitmaps totaling 2L·M·RI bits, where L is the quantity of SD basis and M is the quantity of FD basis with

$M=\lceil p\times \frac{N_3}{R}\rceil .$

When the same approach is reused for CJT Type II CSI feedback, the total quantity of bits for coefficient selection may be scaled with the quantity of TRPs, which may be two TRPs, three TRPs, four TRPs, or more. For example, for CJT Type II CSI feedback with four TRPs and RI=4, the quantity of bits for NZC selection may be increased from 160 bits to 640 bits, which would significantly increase a CSI feedback overhead for CJT Type II CSI feedback.

As an example, for RI=1, eType II CSI feedback for a single TRP may use 40 bits, CJT Type II CSI feedback for two TRPs may use 80 bits, and CJT Type II CSI feedback for four TRPs may use 160 bits. For RI=2, eType II CSI feedback for a single TRP may use 80 bits, CJT Type II CSI feedback for two TRPs may use 160 bits, and CJT Type II CSI feedback for four TRPs may use 320 bits. For RI=3, eType II CSI feedback for a single TRP may use 120 bits, CJT Type II CSI feedback for two TRPs may use 240 bits, and CJT Type II CSI feedback for four TRPs may use 480 bits. For RI=4, eType II CSI feedback for a single TRP may use 160 bits, CJT Type II CSI feedback for two TRPs may use 320 bits, and CJT Type II CSI feedback for four TRPs may use 640 bits. In these examples, L=4, M=5 for all RIs (N₃=19, R=1, p=¼). In these examples, reusing the approach used for eType II CSI feedback for CJT Type II CSI feedback may result in an increase in CSI feedback overhead.

In various aspects of techniques and apparatuses described herein, a UE may receive one or more reference signals from a plurality of TRPs associated with a network entity. The UE may transmit, to the network entity and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report. The CJT Type II CSI feedback report may be based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands. The CJT Type II CSI feedback report may be based at least in part on selecting coefficients from high-priority coefficients (e.g., a configured quantity of high-priority coefficients), and the CJT Type II CSI feedback report may be based at least in part on excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients. As a result, the CJT Type II CSI feedback report may use fewer bits, as compared to applying a single TRP approach for CSI feedback reporting to the plurality of TRPs.

FIG. 6 is a diagram illustrating an example 600 associated with reporting CJT Type II CSI feedback, in accordance with the present disclosure. As shown in FIG. 6, example 600 includes communication between a UE (e.g., UE 120) and a network entity (e.g., base station 110). In some aspects, the UE and the network entity may be included in a wireless network, such as wireless network 100.

As shown by reference number 602, the UE may receive one or more reference signals from a plurality of TRPs (e.g., two or more TRPs) associated with a network entity. The one or more reference signals may include channel state information reference signals (CSI-RSs). The network entity may be associated with the plurality of TRPs, such as a first TRP and a second TRP. In other words, the UE may be configured for a multiple TRP operation.

As shown by reference number 604, the UE may transmit, to the network entity and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report. In some aspects, the CJT Type II CSI feedback report may be based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands. In some aspects, the CJT Type II CSI feedback report may be based at least in part on selecting coefficients from high-priority coefficients (e.g., a configured quantity of high-priority coefficients), and the CJT Type II CSI feedback report may be based at least in part on excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients. The UE may exclude the low-priority coefficients irrespective of the coefficient strengths associated with the low-priority coefficients. In some cases, the network entity may configure a defined ratio between the high-priority coefficients and the low-priority coefficients, instead of an exact quantity of high-priority coefficients. In some aspects, the UE may communicate with the plurality of TRPs based at least in part on the CJT Type II CSI feedback report.

In some aspects, the two-stage FD basis reporting may be applied for the quantity of PMI subbands being less than or equal to 19. A first stage of the two-stage FD basis reporting may include reporting a starting index for a window-based intermediate set. A second stage of the two-stage FD basis reporting may include reporting an FD basis selection for each of a plurality of layers and for each of the plurality of TRPs.

In some aspects, the UE may use the two-stage FD basis reporting, even for N₃≤19 for CJT (e.g., no selection between single and two-stage FD basis report based at least in part on N₃). In the first stage, the UE may report, to the network entity, the starting index for the window-based intermediate set (e.g., down select from N₃ to 2M). A window size may be 2M, where M=max (M_TRPj) and M_TRPj is the quantity of FD basis for TRP-index j. The same window may be used for a plurality of TRPs (e.g., all TRPs) and a plurality of layers (e.g., all layers). The UE may report the starting index M_initial via ┌log₂ 2M┐ bits. Candidate FD bases in the window may be represented by mod(n+M_initial, N₃), n=0 . . . 2M−1. In the second stage, the UE may report, to the network entity, the FD basis for each layer and each TRP. The UE may signal M_TRPj−1 FD bases from 2M−1 candidate FD bases

$\lceil {\log }_2\left(\begin{array}{c}2M-1\\ M_{{\mathrm{TRP}}_j}-1\end{array}\right)\rceil$

bits (for each layer and each TRP). As a result, a total overhead may be reduced from:

${\sum }_j\lceil {\log }_2\left(\begin{array}{c}{N}_3-1\\ M_{{\mathrm{TRP}}_j}-1\end{array}\right)\rceil \times \mathrm{RI}\mathrm{to}\left(\lceil {\log }_{2}2M\rceil +{\sum }_j\lceil {\log }_2\left(\begin{array}{c}2M-1\\ M_{{\mathrm{TRP}}_j}-1\end{array}\right)\rceil \times RI\right).$

As an example, for RI=1, a simple extension (e.g., a simple extension of eType II FD basis selection to CJT mTRP) may use 48 bits, but a two-stage FD basis reporting even for N₃≤19 for CJT may use 32 bits, which is a reduction of 33.3%. For RI=2, the simple extension may use 96 bits, but the two-stage FD basis reporting even for N₃≤19 for CJT may use 60 bits, which is a reduction of 37.5%. For RI=4, the simple extension may use 192 bits, but the two-stage FD basis reporting even for N₃≤19 for CJT may use 116 bits, which is a reduction of 39.6%. In these examples, N_TRP=4, M_TRP=5 for all RIs and TRPs, and N₃=19.

In some aspects, the UE may perform, prior to a coefficient selection and reporting to the network entity, an ordering of a plurality of candidate coefficients for a plurality of layers and for the plurality of TRPs based at least in part on a priority function. The plurality of candidate coefficients may include zero coefficients. The priority function may be based at least in part on a layer index, a TRP index, a spatial domain index, an FD basis index, a permutation function for the TRP index, and a permutation function for the FD basis index. The UE may determine, based at least in part on the ordering of the plurality of candidate coefficients, the high-priority coefficients. A configured quantity of the high-priority coefficients may define a maximum payload size for coefficient selection for the CJT Type II CSI feedback report. Remaining coefficients from the plurality of candidate coefficients may correspond to the low-priority coefficients. The UE may select coefficients from the high-priority coefficients, where the selected coefficients may be used for the coefficient selection and reporting to the network entity. The selected coefficients may be non-zero coefficients.

In some aspects, the UE may not report, to the network entity, low-priority NZCs, irrespective of a strength of the low-priority NZCs. The UE may select NZCs to report, to the network entity, from the high-priority coefficients.

In some aspects, in a first step, the UE may order the plurality of candidate coefficients (e.g., all candidate coefficients) including zero coefficients for a plurality of layers (e.g., all layers) and the plurality of TRPs (e.g., all TRPs) based at least in part on the priority function before NZC selection and reporting. A coefficient c_p1,i1,m1^(l1) have a lower priority than c_p2,i2,m2^(l2) when Prio(l₁, p₁, i₁, m₁)>Prio(l₂, p₂, i₂, m₂), where l is the layer index, p is the TRP index, i is the SD basis index, and m is the FD basis index. A priority level may be defined based at least in part on an order of layer, TRP, SD basis, and FD basis.

As an example, Prio(l, p, i, m)=2L·N_TRP·RI·Perm(m)+N_TRP·RI·i+RI·g(p)+l, where N_TRP is the quantity of TRPs for CJT and g(p) is the permutation function for TRP index p. In a first case, g(p)=p, in which case there is no permutation, and a TRP priority level may be based at least in part on a configured TRP index. In a second case, g(p) may map the TRP index p based at least in part on a power of the associated TRP, where the TRP power may be defined by the power of the strongest coefficient of the associated TRP or by the power of the inter-TRP co-amplitude (e.g., a stronger TRP may be likely to be more significant than a weaker TRP). Further, Perm(m) is the permutation function for the FD basis that is the same as the single TRP case.

In some aspects, in a second step, the UE may select reported NZCs from the high-priority coefficients, and the UE may not report the low-priority coefficients. The UE may assume that not reported low-priority coefficients are zero, even though these not reported low-priority coefficients may not actually be zero. The quantity of high-priority coefficients may define the maximum payload size for coefficient selection for CJT, where a value for the quantity of high-priority coefficients and/or the maximum payload size may be based at least in part on a tradeoff between overhead and performance.

For example,

$K_{\max }=\lceil \gamma ·\frac{N_{\mathrm{TRP}}·2L·M·\mathrm{RI}}{K_{\mathrm{NZ},\max }^{\mathrm{tot}}}\rceil ·K_{\mathrm{NZ},\max }^{\mathrm{tot}},$

where K_NZ,max^tot is the maximum total quantity of NZCs across a plurality of layers (e.g., all layers) and a plurality of TRPs (e.g., TRPs) configured by a higher layer, where γ is an RRC configured ratio for NZC selection overhead reduction. In such a case, an NZC selection bitmap may be reduced from: N_TRP·2LMRI to

$\lceil \gamma ·\frac{N_{\mathrm{TRP}}·2\mathrm{LMRI}}{K_{\mathrm{NZ},\max }^{tot}}\rceil ·K_{\mathrm{NZ},\max }^{tot}.$

As an example, for RI=1, a simple extension (e.g., per-TRP selection and reporting from all the coefficients irrespective of priority) may use 160 bits, but a reporting of coefficient selection from high-priority coefficients may use 80 bits, which is a reduction of 50%. For RI=2, the simple extension may use 320 bits, but the reporting of coefficient selection from high-priority coefficients may use 160 bits, which is a reduction of 50%. For RI=4, the simple extension may use 640 bits, but the reporting of coefficient selection from high-priority coefficients may use 320 bits, which is a reduction of 50%. In these examples, N_TRP=4, L=4, M=5 for all RIs and TRPs and

$\gamma =\frac{1}{2}.$

In some aspects, the UE may transmit, to the network entity, a one-bit indication that indicates whether a joint NZC selection across the plurality of TRPs is used for the CJT Type II CSI feedback report. The joint NZC selection across TRPs may be based at least in part on the priority function. The joint NZC selection may consider only the high priority coefficients.

In some aspects, the one-bit indication may be included in a CSI Part 1, and the one-bit indication may be used to identify the NZC selection bitmap size in CSI Part 2. The one-bit indication may be “0” to indicate that NZC is based at least in part on the simple extension of eType II (e.g., per-TRP selection and reporting from all the coefficients irrespective of priority). The one-bit indication may be “1” to indicate a joint NZC selection across TRPs based at least in part on a priority level with a reduced payload for NZC selection reporting.

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

FIG. 7 is a diagram illustrating an example 700 of reporting CJT Type II CSI feedback, in accordance with the present disclosure.

As shown in FIG. 7, a UE may perform an NZC selection and reporting for CJT Type II CSI feedback. For TRP 0 (e.g., a first TRP), the UE may determine (SD, FD) coefficients for TRP 0 and Layer 0, which may have a size of 2L×M. For TRP 0, the UE may determine (SD, FD) coefficients for TRP 0 and Layer RI−1, which may have a size of 2L×M. For TRP 1 (e.g., a second TRP), the UE may determine (SD, FD) coefficients for TRP 1 and Layer 0, which may have a size of 2L×M. For TRP 1, the UE may determine (SD, FD) coefficients for TRP 1 and Layer RI−1, which may have a size of 2L×M. The UE may perform a packing and an ordering of a plurality of coefficients based at least in part on a priority level, where the plurality of coefficients may be the (SD, FD) coefficients for all of TRP 0 and Layer 0, TRP 0 and Layer RI−1, TRP 1 and Layer 0, and TRP 1 and Layer RI−1. The plurality of coefficients may have a size of 2LM×RI×N_TRP. The UE may form, from the plurality of coefficients, a set of low-priority coefficients. The UE may not report the low-priority coefficients. For example, the UE may set the low-priority coefficients to zero, even for both strong and weak coefficients. The UE may form, from the plurality of coefficients, a set of high-priority coefficients. The high-priority coefficients may have a size of γ×2LM×RI×N_TRP. The UE may perform an NZC selection and reporting of locations of NZCs within the set of high-priority coefficients. As a result, the UE may perform the NZC selection and reporting based at least in part on a priority level for CJT Type II CSI feedback.

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

FIG. 8 is a diagram illustrating an example process 800 performed, for example, by a UE, in accordance with the present disclosure. Example process 800 is an example where the UE (e.g., UE 120) performs operations associated with reporting CJT Type II CSI feedback.

As shown in FIG. 8, in some aspects, process 800 may include receiving one or more reference signals from a plurality of TRPs associated with a network entity (block 810). For example, the UE (e.g., using communication manager 140 and/or reception component 1002, depicted in FIG. 10, and/or using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, and/or controller/processor 280) may receive one or more reference signals from a plurality of TRPs associated with a network entity, as described above.

As further shown in FIG. 8, in some aspects, process 800 may include transmitting, to the network entity and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients (block 820). For example, the UE (e.g., using communication manager 140 and/or transmission component 1004, depicted in FIG. 10, and/or using controller/processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, and/or antenna 252) may transmit, to the network entity and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients, as described above.

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

In a first aspect, the two-stage FD basis reporting is applied for the quantity of PMI subbands being less than or equal to 19.

In a second aspect, alone or in combination with the first aspect, a first stage of the two-stage FD basis reporting includes reporting a starting index for a window-based intermediate set, and a second stage of the two-stage FD basis reporting includes reporting an FD basis selection for each of a plurality of layers and for each of the plurality of TRPs.

In a third aspect, alone or in combination with one or more of the first and second aspects, process 800 includes performing, prior to a coefficient selection and reporting to the network entity, an ordering of a plurality of candidate coefficients for a plurality of layers and for the plurality of TRPs based at least in part on a priority function, wherein the plurality of candidate coefficients include zero coefficients; determining, based at least in part on the ordering of the plurality of candidate coefficients, the high-priority coefficients, wherein remaining coefficients from the plurality of candidate coefficients correspond to the low-priority coefficients; and selecting the coefficients from the high-priority coefficients, wherein the coefficients are associated with the coefficient selection and reporting to the network entity.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the priority function is based at least in part on a layer index, a TRP index, a spatial domain index, an FD basis index, a permutation function for the TRP index, and a permutation function for the FD basis index.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the coefficients are non-zero coefficients, and a configured quantity of the high-priority coefficients defines a maximum payload size for coefficient selection for the CJT Type II CSI feedback report.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, process 800 includes transmitting, to the network entity, a one-bit indication that indicates whether a joint NZC selection across the plurality of TRPs is used for the CJT Type II CSI feedback report, wherein the joint NZC selection is based at least in part on a priority function.

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

FIG. 9 is a diagram illustrating an example process 900 performed, for example, by a network entity, in accordance with the present disclosure. Example process 900 is an example where the network entity (e.g., base station 110) performs operations associated with reporting CJT Type II CSI feedback.

As shown in FIG. 9, in some aspects, process 900 may include transmitting, to a UE and via a plurality of TRPs associated with the network entity, one or more reference signals (block 910). For example, the network entity (e.g., using transmission component 1104, depicted in FIG. 11, and/or using controller/processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, and/or antenna 234) may transmit, to a UE and via a plurality of TRPs associated with the network entity, one or more reference signals, as described above.

As further shown in FIG. 9, in some aspects, process 900 may include receiving, from the UE and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients (block 920). For example, the network entity (e.g., using reception component 1102, depicted in FIG. 11, and/or using antenna 234, DEMOD 232, MIMO detector 236, receive processor 238, and/or controller/processor 240) may receive, from the UE and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients, as described above.

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

In a first aspect, the two-stage FD basis reporting is applied for the quantity of PMI subbands being less than or equal to 19.

In a second aspect, alone or in combination with the first aspect, a first stage of the two-stage FD basis reporting includes reporting a starting index for a window-based intermediate set, and a second stage of the two-stage FD basis reporting includes reporting an FD basis selection for each of a plurality of layers and for each of the plurality of TRPs.

In a third aspect, alone or in combination with one or more of the first and second aspects, an ordering of a plurality of candidate coefficients for a plurality of layers and for the plurality of TRPs is based at least in part on a priority function, wherein the high-priority coefficients are based at least in part on the ordering of the plurality of candidate coefficients, and the coefficients are from the high-priority coefficients.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the priority function is based at least in part on a layer index, a TRP index, a spatial domain index, an FD basis index, a permutation function for the TRP index, and a permutation function for the FD basis index.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the coefficients are non-zero coefficients, and a configured quantity of the high-priority coefficients defines a maximum payload size for coefficient selection for the CJT Type II CSI feedback report.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, process 900 includes receiving, from the UE, a one-bit indication that indicates whether a joint NZC selection across the plurality of TRPs is used for the CJT Type II CSI feedback report, wherein the joint NZC selection is based at least in part on a priority function.

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

FIG. 10 is a diagram of an example apparatus 1000 for wireless communication. The apparatus 1000 may be a UE, or a UE may include the apparatus 1000. In some aspects, the apparatus 1000 includes a reception component 1002 and a transmission component 1004, which may be in communication with one another (for example, via one or more buses and/or one or more other components). As shown, the apparatus 1000 may communicate with another apparatus 1006 (such as a UE, a base station, or another wireless communication device) using the reception component 1002 and the transmission component 1004. As further shown, the apparatus 1000 may include the communication manager 140. The communication manager 140 may include a processing component 1008, among other examples.

In some aspects, the apparatus 1000 may be configured to perform one or more operations described herein in connection with FIGS. 6-7. Additionally, or alternatively, the apparatus 1000 may be configured to perform one or more processes described herein, such as process 800 of FIG. 8. In some aspects, the apparatus 1000 and/or one or more components shown in FIG. 10 may include one or more components of the UE described in connection with FIG. 2. Additionally, or alternatively, one or more components shown in FIG. 10 may be implemented within one or more components described in connection with FIG. 2. Additionally, or alternatively, one or more components of the set of components may be implemented at least in part as software stored in a memory. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or a processor to perform the functions or operations of the component.

The reception component 1002 may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus 1006. The reception component 1002 may provide received communications to one or more other components of the apparatus 1000. In some aspects, the reception component 1002 may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples), and may provide the processed signals to the one or more other components of the apparatus 1000. In some aspects, the reception component 1002 may include one or more antennas, a modem, a demodulator, a MIMO detector, a receive processor, a controller/processor, a memory, or a combination thereof, of the UE described in connection with FIG. 2.

The transmission component 1004 may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus 1006. In some aspects, one or more other components of the apparatus 1000 may generate communications and may provide the generated communications to the transmission component 1004 for transmission to the apparatus 1006. In some aspects, the transmission component 1004 may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples), and may transmit the processed signals to the apparatus 1006. In some aspects, the transmission component 1004 may include one or more antennas, a modem, a modulator, a transmit MIMO processor, a transmit processor, a controller/processor, a memory, or a combination thereof, of the UE described in connection with FIG. 2. In some aspects, the transmission component 1004 may be co-located with the reception component 1002 in a transceiver.

The reception component 1002 may receive one or more reference signals from a plurality of TRPs associated with a network entity. The transmission component 1004 may transmit, to the network entity and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

The processing component 1008 may perform, prior to a coefficient selection and reporting to the network entity, an ordering of a plurality of candidate coefficients for a plurality of layers and for the plurality of TRPs based at least in part on a priority function, wherein the plurality of candidate coefficients include zero coefficients. The processing component 1008 may determine, based at least in part on the ordering of the plurality of candidate coefficients, the high-priority coefficients, wherein remaining coefficients from the plurality of candidate coefficients correspond to the low-priority coefficients. The processing component 1008 may select the coefficients from the high-priority coefficients, wherein the coefficients are associated with the coefficient selection and reporting to the network entity. The transmission component 1004 may transmit, to the network entity, a one-bit indication that indicates whether a joint NZC selection across the plurality of TRPs is used for the CJT Type II CSI feedback report, wherein the joint NZC selection is based at least in part on a priority function.

The number and arrangement of components shown in FIG. 10 are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in FIG. 10. Furthermore, two or more components shown in FIG. 10 may be implemented within a single component, or a single component shown in FIG. 10 may be implemented as multiple, distributed components. Additionally, or alternatively, a set of (one or more) components shown in FIG. 10 may perform one or more functions described as being performed by another set of components shown in FIG. 10.

FIG. 11 is a diagram of an example apparatus 1100 for wireless communication. The apparatus 1100 may be a network entity, or a network entity may include the apparatus 1100. In some aspects, the apparatus 1100 includes a reception component 1102 and a transmission component 1104, which may be in communication with one another (for example, via one or more buses and/or one or more other components). As shown, the apparatus 1100 may communicate with another apparatus 1106 (such as a UE, a base station, or another wireless communication device) using the reception component 1102 and the transmission component 1104.

In some aspects, the apparatus 1100 may be configured to perform one or more operations described herein in connection with FIGS. 6-7. Additionally, or alternatively, the apparatus 1100 may be configured to perform one or more processes described herein, such as process 900 of FIG. 9. In some aspects, the apparatus 1100 and/or one or more components shown in FIG. 11 may include one or more components of the network entity described in connection with FIG. 2. Additionally, or alternatively, one or more components shown in FIG. 11 may be implemented within one or more components described in connection with FIG. 2. Additionally, or alternatively, one or more components of the set of components may be implemented at least in part as software stored in a memory. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or a processor to perform the functions or operations of the component.

The reception component 1102 may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus 1106. The reception component 1102 may provide received communications to one or more other components of the apparatus 1100. In some aspects, the reception component 1102 may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples), and may provide the processed signals to the one or more other components of the apparatus 1100. In some aspects, the reception component 1102 may include one or more antennas, a modem, a demodulator, a MIMO detector, a receive processor, a controller/processor, a memory, or a combination thereof, of the network entity described in connection with FIG. 2.

The transmission component 1104 may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus 1106. In some aspects, one or more other components of the apparatus 1100 may generate communications and may provide the generated communications to the transmission component 1104 for transmission to the apparatus 1106. In some aspects, the transmission component 1104 may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples), and may transmit the processed signals to the apparatus 1106. In some aspects, the transmission component 1104 may include one or more antennas, a modem, a modulator, a transmit MIMO processor, a transmit processor, a controller/processor, a memory, or a combination thereof, of the network entity described in connection with FIG. 2. In some aspects, the transmission component 1104 may be co-located with the reception component 1102 in a transceiver.

The transmission component 1104 may transmit, to a UE and via a plurality of TRPs associated with the network entity, one or more reference signals. The reception component 1102 may receive, from the UE and based at least in part on the one or more reference signals, a CJT Type II CSI feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage FD basis reporting irrespective of a quantity of PMI subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients. The reception component 1102 may receive, from the UE, a one-bit indication that indicates whether a joint NZC selection across the plurality of TRPs is used for the CJT Type II CSI feedback report, wherein the joint NZC selection is based at least in part on a priority function.

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

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

• • Aspect 1: A method of wireless communication performed by a user equipment (UE), comprising: receiving one or more reference signals from a plurality of transmit receive points (TRPs) associated with a network entity; and transmitting, to the network entity and based at least in part on the one or more reference signals, a coherent joint transmission (CJT) Type II channel state information (CSI) feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage frequency domain (FD) basis reporting irrespective of a quantity of precoding matrix indicator (PMI) subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.
  • Aspect 2: The method of Aspect 1, wherein the two-stage FD basis reporting is applied for the quantity of PMI subbands being less than or equal to 19.
  • Aspect 3: The method of any of Aspects 1 through 2, wherein a first stage of the two-stage FD basis reporting includes reporting a starting index for a window-based intermediate set, and wherein a second stage of the two-stage FD basis reporting includes reporting an FD basis selection for each of a plurality of layers and for each of the plurality of TRPs.
  • Aspect 4: The method of any of Aspects 1 through 3, further comprising: performing, prior to a coefficient selection and reporting to the network entity, an ordering of a plurality of candidate coefficients for a plurality of layers and for the plurality of TRPs based at least in part on a priority function, wherein the plurality of candidate coefficients include zero coefficients; determining, based at least in part on the ordering of the plurality of candidate coefficients, the high-priority coefficients, wherein remaining coefficients from the plurality of candidate coefficients correspond to the low-priority coefficients; and selecting the coefficients from the high-priority coefficients, wherein the coefficients are associated with the coefficient selection and reporting to the network entity.
  • Aspect 5: The method of Aspect 4, wherein the priority function is based at least in part on a layer index, a TRP index, a spatial domain index, an FD basis index, a permutation function for the TRP index, and a permutation function for the FD basis index.
  • Aspect 6: The method of Aspect 4, wherein the coefficients are non-zero coefficients, and wherein a configured quantity of the high-priority coefficients defines a maximum payload size for coefficient selection for the CJT Type II CSI feedback report.
  • Aspect 7: The method of any of Aspects 1 through 6, further comprising: transmitting, to the network entity, a one-bit indication that indicates whether a joint non-zero coefficient (NZC) selection across the plurality of TRPs is used for the CJT Type II CSI feedback report, wherein the joint NZC selection is based at least in part on a priority function.
  • Aspect 8: A method of wireless communication performed by a network entity, comprising: transmitting, to a user equipment (UE) and via a plurality of transmit receive points (TRPs) associated with the network entity, one or more reference signals; and receiving, from the UE and based at least in part on the one or more reference signals, a coherent joint transmission (CJT) Type II channel state information (CSI) feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage frequency domain (FD) basis reporting irrespective of a quantity of precoding matrix indicator (PMI) subbands, or wherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.
  • Aspect 9: The method of Aspect 8, wherein the two-stage FD basis reporting is applied for the quantity of PMI subbands being less than or equal to 19.
  • Aspect 10: The method of any of Aspects 8 through 9, wherein a first stage of the two-stage FD basis reporting includes reporting a starting index for a window-based intermediate set, and wherein a second stage of the two-stage FD basis reporting includes reporting an FD basis selection for each of a plurality of layers and for each of the plurality of TRPs.
  • Aspect 11: The method of any of Aspects 8 through 10, wherein an ordering of a plurality of candidate coefficients for a plurality of layers and for the plurality of TRPs is based at least in part on a priority function, wherein the high-priority coefficients are based at least in part on the ordering of the plurality of candidate coefficients, and wherein the coefficients are from the high-priority coefficients.
  • Aspect 12: The method of Aspect 11, wherein the priority function is based at least in part on a layer index, a TRP index, a spatial domain index, an FD basis index, a permutation function for the TRP index, and a permutation function for the FD basis index.
  • Aspect 13: The method of Aspect 11, wherein the coefficients are non-zero coefficients, and wherein a configured quantity of the high-priority coefficients defines a maximum payload size for coefficient selection for the CJT Type II CSI feedback report.
  • Aspect 14: The method of any of Aspects 8 through 13, further comprising: receiving, from the UE, a one-bit indication that indicates whether a joint non-zero coefficient (NZC) selection across the plurality of TRPs is used for the CJT Type II CSI feedback report, wherein the joint NZC selection is based at least in part on a priority function.
  • Aspect 15: An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of one or more of Aspects 1-7.
  • Aspect 16: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the one or more processors configured to perform the method of one or more of Aspects 1-7.
  • Aspect 17: An apparatus for wireless communication, comprising at least one means for performing the method of one or more of Aspects 1-7.
  • Aspect 18: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of one or more of Aspects 1-7.
  • Aspect 19: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more of Aspects 1-7.
  • Aspect 20: An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of one or more of Aspects 8-14.
  • Aspect 21: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the one or more processors configured to perform the method of one or more of Aspects 8-14.
  • Aspect 22: An apparatus for wireless communication, comprising at least one means for performing the method of one or more of Aspects 8-14.
  • Aspect 23: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of one or more of Aspects 8-14.
  • Aspect 24: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more of Aspects 8-14.

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

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

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

Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. Many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. The disclosure of various aspects includes each dependent claim in combination with every other claim in the claim set. As used herein, a phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a+b, a+c, b+c, and a+b+c, as well as any combination with multiples of the same element (e.g., a+a, a+a+a, a+a+b, a+a+c, a+b+b, a+c+c, b+b, b+b+b, b+b+c, c+c, and c+c+c, or any other ordering of a, b, and c).

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

Claims

1. An apparatus for wireless communication at a user equipment (UE), comprising: a memory; andone or more processors, coupled to the memory, configured to: receive one or more reference signals from a plurality of transmit receive points (TRPs) associated with a network entity; andtransmit, to the network entity and based at least in part on the one or more reference signals, a coherent joint transmission (CJT) Type II channel state information (CSI) feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage frequency domain (FD) basis reporting irrespective of a quantity of precoding matrix indicator (PMI) subbands, orwherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

2. The apparatus of claim 1, wherein the two-stage FD basis reporting is applied for the quantity of PMI subbands being less than or equal to 19.

3. The apparatus of claim 1, wherein a first stage of the two-stage FD basis reporting includes reporting a starting index for a window-based intermediate set, and wherein a second stage of the two-stage FD basis reporting includes reporting an FD basis selection for each of a plurality of layers and for each of the plurality of TRPs.

4. The apparatus of claim 1, wherein the one or more processors are further configured to: perform, prior to a coefficient selection and reporting to the network entity, an ordering of a plurality of candidate coefficients for a plurality of layers and for the plurality of TRPs based at least in part on a priority function, wherein the plurality of candidate coefficients include zero coefficients;determine, based at least in part on the ordering of the plurality of candidate coefficients, the high-priority coefficients, wherein remaining coefficients from the plurality of candidate coefficients correspond to the low-priority coefficients; andselecting the coefficients from the high-priority coefficients, wherein the coefficients are associated with the coefficient selection and reporting to the network entity.

5. The apparatus of claim 4, wherein the priority function is based at least in part on a layer index, a TRP index, a spatial domain index, an FD basis index, a permutation function for the TRP index, and a permutation function for the FD basis index.

6. The apparatus of claim 4, wherein the coefficients are non-zero coefficients.

7. The apparatus of claim 4, wherein a configured quantity of the high-priority coefficients defines a maximum payload size for coefficient selection for the CJT Type II CSI feedback report.

8. The apparatus of claim 1, wherein the one or more processors are further configured to: transmit, to the network entity, a one-bit indication that indicates whether a joint non-zero coefficient (NZC) selection across the plurality of TRPs is used for the CJT Type II CSI feedback report, wherein the joint NZC selection is based at least in part on a priority function.

9. An apparatus for wireless communication at a network entity, comprising: a memory; andone or more processors, coupled to the memory, configured to: transmit, to a user equipment (UE) and via a plurality of transmit receive points (TRPs) associated with the network entity, one or more reference signals; andreceive, from the UE and based at least in part on the one or more reference signals, a coherent joint transmission (CJT) Type II channel state information (CSI) feedback report, wherein the CJT Type II CSI feedback report is based at least in part on a two-stage frequency domain (FD) basis reporting irrespective of a quantity of precoding matrix indicator (PMI) subbands, orwherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

10. The apparatus of claim 9, wherein the two-stage FD basis reporting is applied for the quantity of PMI subbands being less than or equal to 19.

11. The apparatus of claim 9, wherein a first stage of the two-stage FD basis reporting includes reporting a starting index for a window-based intermediate set, and wherein a second stage of the two-stage FD basis reporting includes reporting an FD basis selection for each of a plurality of layers and for each of the plurality of TRPs.

12. The apparatus of claim 9, wherein an ordering of a plurality of candidate coefficients for a plurality of layers and for the plurality of TRPs is based at least in part on a priority function, wherein the high-priority coefficients are based at least in part on the ordering of the plurality of candidate coefficients, and wherein the coefficients are from the high-priority coefficients.

13. The apparatus of claim 12, wherein the priority function is based at least in part on a layer index, a TRP index, a spatial domain index, an FD basis index, a permutation function for the TRP index, and a permutation function for the FD basis index.

14. The apparatus of claim 12, wherein the coefficients are non-zero coefficients.

15. The apparatus of claim 12, wherein a configured quantity of the high-priority coefficients defines a maximum payload size for coefficient selection for the CJT Type II CSI feedback report.

16. The apparatus of claim 9, wherein the one or more processors are further configured to: receive, from the UE, a one-bit indication that indicates whether a joint non-zero coefficient (NZC) selection across the plurality of TRPs is used for the CJT Type II CSI feedback report, wherein the joint NZC selection is based at least in part on a priority function.

17. A method of wireless communication performed by a user equipment (UE), comprising: receiving one or more reference signals from a plurality of transmit receive points (TRPs) associated with a network entity; andtransmitting, to the network entity and based at least in part on the one or more reference signals, a coherent joint transmission (CJT) Type II channel state information (CSI) feedback report,wherein the CJT Type II CSI feedback report is based at least in part on a two-stage frequency domain (FD) basis reporting irrespective of a quantity of precoding matrix indicator (PMI) subbands, orwherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

18. The method of claim 17, wherein the two-stage FD basis reporting is applied for the quantity of PMI subbands being less than or equal to 19.

19. The method of claim 17, wherein a first stage of the two-stage FD basis reporting includes reporting a starting index for a window-based intermediate set, and wherein a second stage of the two-stage FD basis reporting includes reporting an FD basis selection for each of a plurality of layers and for each of the plurality of TRPs.

20. The method of claim 17, further comprising: performing, prior to a coefficient selection and reporting to the network entity, an ordering of a plurality of candidate coefficients for a plurality of layers and for the plurality of TRPs based at least in part on a priority function, wherein the plurality of candidate coefficients include zero coefficients;determining, based at least in part on the ordering of the plurality of candidate coefficients, the high-priority coefficients, wherein remaining coefficients from the plurality of candidate coefficients correspond to the low-priority coefficients; andselecting the coefficients from the high-priority coefficients, wherein the coefficients are associated with the coefficient selection and reporting to the network entity.

21. The method of claim 20, wherein the priority function is based at least in part on a layer index, a TRP index, a spatial domain index, an FD basis index, a permutation function for the TRP index, and a permutation function for the FD basis index.

22. The method of claim 20, wherein the coefficients are non-zero coefficients, and wherein a configured quantity of the high-priority coefficients defines a maximum payload size for coefficient selection for the CJT Type II CSI feedback report.

23. The method of claim 17, further comprising: transmitting, to the network entity, a one-bit indication that indicates whether a joint non-zero coefficient (NZC) selection across the plurality of TRPs is used for the CJT Type II CSI feedback report, wherein the joint NZC selection is based at least in part on a priority function.

24. A method of wireless communication performed by a network entity, comprising: transmitting, to a user equipment (UE) and via a plurality of transmit receive points (TRPs) associated with the network entity, one or more reference signals; andreceiving, from the UE and based at least in part on the one or more reference signals, a coherent joint transmission (CJT) Type II channel state information (CSI) feedback report,wherein the CJT Type II CSI feedback report is based at least in part on a two-stage frequency domain (FD) basis reporting irrespective of a quantity of precoding matrix indicator (PMI) subbands, orwherein the CJT Type II CSI feedback report is based at least in part on selecting coefficients from high-priority coefficients and excluding low-priority coefficients irrespective of coefficient strengths associated with the low-priority coefficients.

25. The method of claim 24, wherein the two-stage FD basis reporting is applied for the quantity of PMI subbands being less than or equal to 19.

26. The method of claim 24, wherein a first stage of the two-stage FD basis reporting includes reporting a starting index for a window-based intermediate set, and wherein a second stage of the two-stage FD basis reporting includes reporting an FD basis selection for each of a plurality of layers and for each of the plurality of TRPs.

27. The method of claim 24, wherein an ordering of a plurality of candidate coefficients for a plurality of layers and for the plurality of TRPs is based at least in part on a priority function, wherein the high-priority coefficients are based at least in part on the ordering of the plurality of candidate coefficients, and wherein the coefficients are from the high-priority coefficients.

28. The method of claim 27, wherein the priority function is based at least in part on a layer index, a TRP index, a spatial domain index, an FD basis index, a permutation function for the TRP index, and a permutation function for the FD basis index.

29. The method of claim 27, wherein the coefficients are non-zero coefficients, and wherein a configured quantity of the high-priority coefficients defines a maximum payload size for coefficient selection for the CJT Type II CSI feedback report.

30. The method of claim 24, further comprising: receiving, from the UE, a one-bit indication that indicates whether a joint non-zero coefficient (NZC) selection across the plurality of TRPs is used for the CJT Type II CSI feedback report, wherein the joint NZC selection is based at least in part on a priority function.