Techniques for facilitating 8TX uplink MIMO transmission

Abstract

A user equipment (UE) receives control signaling for an uplink (UL) multiple-input multiple-output (MIMO) transmission, and transmits the UL MIMO transmission precoded with an 8-port uplink MIMO predecoder based on the control signaling and a set of two or more antenna port groups.

Description

Technical Field

[0001] The present disclosure relates generally to communication systems, and more particularly, to codebook-based uplink transmissions. Background Art

[0002] Wireless communication systems are widely deployed to provide a variety of 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. 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, and time division synchronous code division multiple access (TD-SCDMA) systems.

[0003] These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate at a city, country, region, and even global level. An example of a telecommunication standard is 5G New Radio (NR). 5G NR is part of the continued mobile broadband evolution promulgated by the 3rd Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with the Internet of Things (IoT)) and other requirements. 5G NR includes services associated with enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable low-latency communications (URLLC). Certain aspects of 5G NR may be based on the 4G Long Term Evolution (LTE) standard. 5G NR technology needs to be further improved. In addition, these improvements may also apply to other multiple access technologies and telecommunication standards that employ these technologies. Summary of the Invention

[0004] The following presents a simplified summary of one or more aspects in order to provide a basic understanding of these aspects. This summary is not an extensive overview of all contemplated aspects. This summary is not intended to identify key or critical elements of all aspects, nor is it intended to delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that will be presented later.

[0005] In one aspect of the present disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus is configured to: receive control signaling for an uplink MIMO transmission, the control signaling including a first TPMI field, a second TPMI field, and an SRS resource set indicator; and transmit the uplink MIMO transmission pre-decoded using an 8-port uplink MIMO pre-decoder based on a 4-port uplink MIMO codebook and a mapping indicated by one or more of the first TPMI field, the second TPMI field, or the SRS resource set indicator.

[0006] In one aspect of the present disclosure, a method, a computer-readable medium, and an apparatus are provided. For example, the apparatus is configured to: output control signaling for an uplink MIMO transmission for transmission, the control signaling including a first TPMI field, a second TPMI field, and an SRS resource set indicator; and receive the uplink MIMO transmission pre-decoded using an 8-port uplink MIMO pre-decoder based on a 4-port uplink MIMO codebook and a mapping indicated by one or more of the first TPMI field, the second TPMI field, or the SRS resource set indicator.

[0007] In one aspect of the present disclosure, a method, computer-readable medium, and apparatus are provided. The apparatus is configured to: receive control signaling for an UL MIMO transmission; and transmit an UL MIMO transmission precoded with an 8-port uplink MIMO precoder based on the control signaling and a set of two or more antenna port groups.

[0008] In one aspect of the present disclosure, a method, computer-readable medium, and apparatus are provided. The apparatus is configured to: output control signaling for an UL MIMO transmission for transmission; and obtain, based on the control signaling and a set of two or more antenna port groups, an UL MIMO transmission precoded using an 8-port uplink MIMO precoder.

[0009] To accomplish the foregoing and related ends, one or more aspects include the features fully described below and particularly pointed out in the claims. The following description and accompanying drawings set forth in detail certain illustrative features of one or more aspects. However, these features are indicative of only some of the various ways in which the principles of the various aspects may be employed. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a diagram illustrating an example of a wireless communication system and an access network.

[0011] Figure 2Ais a diagram illustrating an example of a first frame according to various aspects of the present disclosure.

[0012] Figure 2B is a diagram illustrating an example of DL channels within a subframe according to various aspects of the present disclosure.

[0013] Figure 2C is a diagram illustrating an example of a second frame according to various aspects of the present disclosure.

[0014] Figure 2D is a diagram illustrating an example of a UL channel within a subframe according to various aspects of the present disclosure.

[0015] Figure 3 is a diagram illustrating an example of a base station and a user equipment (UE) in an access network.

[0016] Figure 4 An example UE communicating with a network node according to various aspects of the present disclosure is illustrated.

[0017] Figure 5 An example communication flow between a network node and a UE according to various aspects of the present disclosure is illustrated.

[0018] Figure 6 Depicted are tables illustrating example mappings of SRS resource set indicators to SRI and TPMI fields in accordance with various aspects of the present disclosure.

[0019] Figure 7 Depicted are tables that map values ​​of a first TPMI field to a rank and precoding matrix for a first repetition set to facilitate uplink 4Tx MIMO in accordance with various aspects of the present disclosure.

[0020] Figure 8 Depicted is a table that maps values ​​of a second TPMI field to a precoding matrix for a second repetition set to facilitate uplink 4Tx MIMO in accordance with various aspects of the present disclosure.

[0021] Figure 9 Depicted is a table storing a codebook subset for a precoding matrix W for single-layer transmission for a UE with four antenna ports, in accordance with various aspects of the present disclosure.

[0022] Figure 10 Depicted is a table of a codebook subset storing a precoding matrix W for two-layer transmission for a UE with four antenna ports as presented herein.

[0023] Figure 11 Depicted is a table of a codebook subset storing a precoding matrix W for three-layer transmission for a UE with four antenna ports as presented herein.

[0024] Figure 12 Depicted is a table of a codebook subset storing a precoding matrix W for four-layer transmission for a UE with four antenna ports as presented herein.

[0025] Figure 13 An example UE communicating with a network node according to various aspects of the present disclosure is illustrated.

[0026] Figure 14 Depicted is a table including example 8Tx precoding matrix types for ranks 1 through 8 as presented herein.

[0027] Figure 15 The communication flow between a network node and a UE as presented herein is illustrated.

[0028] Figure 16 Depicted are example tables that facilitate mapping type indicator and TPMI fields to an 8Tx precoding matrix as presented herein.

[0029] Figure 17 The communication flow between a network node and a UE as presented herein is illustrated.

[0030] Figure 18 Depicted is a table that facilitates mapping the type indicator, modified SR field, and TPMI field to the 8Tx precoding matrix as presented herein.

[0031] Figure 19 Depicted is a table that facilitates mapping the type indicator, modified SR field, and TPMI field to the 8Tx precoding matrix as presented herein.

[0032] Figure 20 The communication flow between a network node and a UE as presented herein is illustrated.

[0033] Figure 21 Depicted is a table that facilitates mapping the type indicator and TPMI fields to the 8Tx precoding matrix as presented herein.

[0034] Figure 22 Depicted is a table that facilitates mapping the type indicator and TPMI fields to the 8Tx precoding matrix as presented herein.

[0035] Figure 23 The communication flow between a network node and a UE as presented herein is illustrated.

[0036] Figure 24 Depicted are tables including precoding matrix types for rank 1 through rank 4 as presented herein.

[0037] Figure 25 Depicted is 2500 including precoding matrix types for rank 5 through rank 8 as presented herein.

[0038] Figure 26 An example of an 8Tx fully coherent (FC) codebook structure as presented herein is illustrated.

[0039] Figure 27 Depicted is a table that facilitates mapping the type indicator and TPMI fields to the 8Tx precoding matrix as presented herein.

[0040] Figure 28 Depicted is a table that facilitates mapping the type indicator and TPMI fields to the 8Tx precoding matrix as presented herein.

[0041] Figure 29 The communication flow between a network node and a UE as presented herein is illustrated.

[0042] Figures 30 to 47 Depicted are example tables illustrating uplink precoding matrix indications for ranks 1 through 8 as presented herein.

[0043] Figure 48 An example table showing the mapping of TPMI bit fields to codebook subsets is illustrated.

[0044] Figure 49 An example table showing the mapping of TPMI bit fields to layers for transmission is illustrated.

[0045] Figure 50 Example precoding matrices for rank-5, rank-6, rank-7, and rank-8 UL MIMO transmissions are illustrated.

[0046] Figure 51 Example precoding matrices for rank-5, rank-6, rank-7, and rank-8 UL MIMO transmissions are illustrated.

[0047] Figure 52 Example precoding matrices for rank-5, rank-6, rank-7, and rank-8 UL MIMO transmissions are illustrated.

[0048] Figure 53 Example precoders for rank-5, rank-6, rank-7, and rank-8 UL MIMO transmissions are illustrated.

[0049] Figure 54 Example precoders for rank-5, rank-6, rank-7, and rank-8 UL MIMO transmissions are illustrated.

[0050] Figure 55A 、 Figure 55B and Figure 55C Example antenna port groups are illustrated.

[0051] Figure 55D An example mapping of bit fields to codebook subsets for UL MIMO transmission is illustrated.

[0052] Figure 55E An example communication flow between a UE and a base station in conjunction with antenna port groups is illustrated.

[0053] Figure 56A and Figure 56B Example aspects of SRS resources configured for antenna ports in an antenna port group are illustrated.

[0054] Figure 57A is a flow chart of a method of wireless communication.

[0055] Figure 57B is a flow chart of a method of wireless communication.

[0056] Figure 58A is a flow chart of a method of wireless communication.

[0057] Figure 58B is a flow chart of a method of wireless communication.

[0058] Figure 59 are diagrams illustrating examples of hardware implementations for example apparatuses and / or UEs.

[0059] Figure 60A is a flow chart of a method of wireless communication.

[0060] Figure 60B is a flow chart of a method of wireless communication.

[0061] Figure 61A is a flow chart of a method of wireless communication.

[0062] Figure 61B is a flow chart of a method of wireless communication.

[0063] Figure 62 is a diagram illustrating an example of a hardware implementation for an example network entity. DETAILED DESCRIPTION

[0064] As wireless communication technology evolves, additional types of UEs may be supported, generally referred to herein as "advanced UEs." Advanced UEs may include smartphones, indoor customer premises equipment (CPE), outdoor CPE, laptops, etc. Advanced UEs may be associated with higher reliability and / or improved efficiency compared to non-advanced UEs. Advanced UEs may include more than four antennas, such as Figure 4 UE 400 may have eight antenna elements. Advanced UEs may additionally or alternatively have more relevant power constraints. Additionally, advanced UEs may support more than four downlink layers and / or four uplink transmit ports. Advanced UEs may also support new DMRS, SRS, and / or codebook designs.

[0065] As an increased number of transmit antennas (Tx) (e.g., greater than four transmit antennas) is considered for advanced UEs (e.g., mobile devices, larger size devices, etc.) utilizing 5G technology, support for 8-port uplink transmission may be beneficial for improving 5G performance.

[0066] For 8-port uplink transmissions, a new codebook for precoding and related precoding scheduling information in DCI can be utilized. A first type of codebook can be used for uplink transmissions with precoding disabled. This codebook can use a new design for 8 ports. Additionally, the new design can be used for ranks 5 to 8 (e.g., five-layer, six-layer, seven-layer, or eight-layer uplink transmissions). A second type of codebook can be used for uplink transmissions with precoding enabled. This codebook can use a new design for 8 ports.

[0067] Therefore, it can be understood that 8Tx uplink MIMO can adopt 8Tx uplink operation supporting four or more layers per UE in uplink transmission. To achieve 8Tx uplink operation, the uplink DMRS, SRS, SRS resource indicator (SRI) and / or TPMI (including codebook) can be updated.

[0068] Aspects disclosed herein facilitate 8Tx uplink MIMO. Example techniques include reusing a 4Tx codebook and / or TPMI table, generating a new 8Tx codebook, and control signaling to indicate to the UE the precoder to use when employing 8Tx uplink MIMO.

[0069] The detailed description set forth below in conjunction with the accompanying drawings is a description of various configurations and does not represent the only configurations in which the concepts described herein can be practiced. The detailed description includes specific details to provide a thorough understanding of the various concepts. However, these concepts may be practiced without these specific details. In some cases, well-known structures and components are shown in block diagram form to avoid obscuring these concepts.

[0070] Several aspects of telecommunication systems are presented with reference to various apparatus and methods. These apparatus and methods are described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as "elements"). These elements can be implemented using electronic hardware, computer software, or any combination thereof. Whether these elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0071] For example, an element, or any part of an element, or any combination of elements can be implemented as a "processing system", which includes one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs), central processing units (CPUs), application processors, digital signal processors (DSPs), reduced instruction set computing (RISC) processors, systems on chip (SoCs), baseband processors, field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gate logic components, discrete hardware circuits, and other suitable hardware configured to perform various functionalities described throughout this disclosure. One or more processors in a processing system can execute software. Whether referred to as software, firmware, middleware, microcode, hardware description language, or other terms, software should be broadly interpreted as meaning instructions, instruction sets, codes, code segments, program codes, programs, subroutines, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, or any combination thereof.

[0072] Thus, in one or more example aspects, specific implementations and / or use cases, the functions described may be implemented in hardware, software, or any combination thereof. In the case of implementation in software, the functions may be stored or encoded as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media. A storage medium may be any available medium that can be accessed by a computer. For example, such computer-readable media may include random access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of these types of computer-readable media, or any other medium that can be used to store computer-executable code in the form of instructions or data structures that can be accessed by a computer.

[0073] Although various aspects, specific implementations and / or use cases are described in this application by illustrating some examples, additional or different aspects, specific implementations and use cases may be generated in many different arrangements and scenarios. The various aspects, specific implementations and / or use cases described herein may be implemented across many different platform types, devices, systems, shapes, sizes and packaging arrangements. For example, various aspects, specific implementations and / or use cases may be generated via integrated chip implementations and other devices based on non-module components (e.g., end-user devices, vehicles, communication equipment, computing equipment, industrial equipment, retail / purchase equipment, medical equipment, devices that enable artificial intelligence (AI), etc.). Although some examples may or may not be specifically for use cases or applications, the examples described may have a wide range of applicability. Various aspects, specific implementations and / or use cases may be implemented from chip-level or modular components to non-modular, non-chip-level implementations and further to the range of aggregated, distributed or original equipment manufacturer (OEM) devices or systems in combination with one or more technologies herein. In some actual environments, the equipment in combination with the various aspects and features described may also include additional components and features for implementing and practicing the claimed and described aspects. For example, the transmission and reception of wireless signals necessarily include multiple components for both analog and digital purposes (e.g., hardware components including antennas, RF chains, power amplifiers, modulators, buffers, processors, interleavers, adders / summers, etc.). The techniques described herein can be practiced in a wide variety of devices of various sizes, shapes, and configurations, including chip-level components, systems, distributed arrangements, aggregated or disaggregated components, end-user devices, and the like.

[0074] The deployment of a communication system (such as a 5G NR system) can be arranged in a variety of ways using 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 radio access network (RAN) node, a core network node, a network element, or a network equipment (such as a base station (BS), or one or more units (or one or more components) that perform base station functionality) can be implemented in an aggregated or decomposed architecture. For example, a BS (such as a Node B (NB), an evolved NB (eNB), an NR BS, a 5G NB, an access point (AP), a transmit receive point (TRP), or a cell, etc.) can be implemented as an aggregated base station (also known as a standalone BS or a monolithic BS) or a decomposed base station.

[0075] A converged base station may be configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node. A decomposed base station may be configured to utilize a protocol stack that is physically or logically distributed between two or more units, such as one or more central or centralized units (CUs), one or more distributed units (DUs), or one or more radio units (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 across one or more other RAN nodes. A DU may be implemented to communicate with one or more RUs. Each of the CU, DU, and RU may be implemented as a virtual unit, namely a virtual central unit (VCU), a virtual distributed unit (VDU), or a virtual radio unit (VRU).

[0076] Base station operation or network design may take into account the aggregated nature of base station functionality. For example, a disaggregated base station may be used in an integrated access backhaul (IAB) network, an open radio access network (O-RAN (a network configuration such as that initiated 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 virtually distributing functionality of at least one unit, which may enable flexibility in network design. Each unit of a disaggregated base station or disaggregated RAN architecture may be configured for wired or wireless communication with at least one other unit.

[0077] Figure 1 FIG100 is a diagram illustrating an example of a wireless communication system and access network. The illustrated wireless communication system includes a disaggregated base station architecture. The disaggregated base station architecture may include one or more CUs (e.g., CU 110), which may communicate directly with a core network 120 via a backhaul link or indirectly with the core network 120 through one or more disaggregated base station units (e.g., a near real-time (near-RT) RAN intelligent controller (RIC) 125 via an E2 link, a non-real-time (non-RT) RIC 115 associated with a service management and orchestration (SMO) framework (e.g., SMO framework 105), or both). CU 110 may communicate with one or more DUs (e.g., DU 130) via corresponding midhaul links (e.g., F1 interfaces). DU 130 may communicate with one or more RUs (e.g., RU 140) via corresponding fronthaul links. RU 140 may communicate with corresponding UEs (e.g., UE 104) via one or more radio frequency (RF) access links. In some implementations, UE 104 can be served by multiple RUs simultaneously.

[0078] Each of the units (i.e., CU (e.g., CU 110), DU (e.g., DU 130), RU (e.g., RU 140), and near-RT RIC (e.g., near-RT RIC 125), non-RT RIC (e.g., non-RT RIC 115), and SMO framework 105) may include 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 these units, or an associated processor or controller that provides instructions to the communication interfaces of these units, may be configured to communicate with one or more of the other units via the transmission medium. For example, these units may include a wired interface configured to receive signals or transmit signals to one or more of the other units via the wired transmission medium. Additionally, these units may include a wireless interface that may include a receiver, transmitter, or transceiver (such as an RF transceiver) configured to receive or transmit signals to one or more of the other units via the wireless transmission medium.

[0079] In some aspects, the CU 110 may host one or more higher layer control functions. Such control functions may include radio resource control (RRC), packet data convergence protocol (PDCP), service data adaptation protocol (SDAP), etc. Each control function may be implemented using an interface that is configured to communicate signals with other control functions hosted by the CU 110. The CU 110 may be configured to handle user plane functionality (i.e., central unit-user plane (CU-UP)), control plane functionality (i.e., central unit-control plane (CU-CP)), or a combination thereof. In some specific implementations, the CU 110 may be logically split into one or more CU-UP units and one or more CU-CP units. When implemented in an O-RAN configuration, the CU-UP unit may communicate bidirectionally with the CU-CP unit via an interface (such as an E1 interface). As needed, the CU 110 may be implemented to communicate with the DU 130 for network control and signaling.

[0080] DU 130 may correspond to a logical unit that includes one or more base station functions for controlling the operation of one or more RUs. In some aspects, DU 130 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more higher physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation, demodulation, etc.) at least in part according to a functional split (such as that defined by 3GPP). In some aspects, DU 130 may also host one or more lower PHY layers. Each layer (or module) may be implemented using an interface that is configured to communicate signals with other layers (and modules) hosted by DU 130 or with control functions hosted by CU 110.

[0081] Lower layer functionality may be implemented by one or more RUs. In some deployments, the RU 140 controlled by the DU 130 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, etc.), or both, based at least in part on functional splitting (such as lower layer functional splitting). In this architecture, the RU 140 may be implemented to handle over-the-air (OTA) communications with one or more UEs (e.g., UE 104). In some specific implementations, real-time and non-real-time aspects of control plane and user plane communications with the RU 140 may be controlled by the corresponding DU. In some scenarios, this configuration may enable the implementation of the DU and CU 110 in a cloud-based RAN architecture (such as a vRAN architecture).

[0082] The SMO framework 105 can be configured to support RAN deployment and configuration of non-virtualized network elements and virtualized network elements. For non-virtualized network elements, the SMO framework 105 can be configured to support the deployment of dedicated physical resources for RAN coverage requirements, which can be managed via an operation and maintenance interface (such as an O1 interface). For virtualized network elements, the SMO framework 105 can be configured to interact with a cloud computing platform (such as Open Cloud (O-Cloud) 190) to perform network element lifecycle management (such as instantiating virtualized network elements) via a cloud computing platform interface (such as an O2 interface). Such virtualized network elements may include, but are not limited to, CUs, DUs, RUs, and near-RT RICs. In some specific implementations, the SMO framework 105 can communicate with hardware aspects of the 4G RAN, such as open eNBs (O-eNBs) 111, via the O1 interface. Additionally, in some specific implementations, the SMO framework 105 can communicate directly with one or more RUs via the O1 interface. The SMO framework 105 may also include a non-RT RIC 115 configured to support the functionality of the SMO framework 105 .

[0083] The non-RT RIC 115 may be configured to include logic functions that implement non-real-time control and optimization of RAN elements and resources, artificial intelligence (AI) / machine learning (ML) (AI / ML) workflows including model training and updating, or policy-based guidance of applications / features in the near-RT RIC 125. The non-RT RIC 115 may be coupled to or in communication with the near-RT RIC 125 (e.g., via an A1 interface). The near-RT RIC 125 may be configured to include logic functions that implement near-real-time control and optimization of RAN elements and resources through data collection and actions over an interface (e.g., via an E2 interface) that connects one or more CUs, one or more DUs, or both, and the O-eNB with the near-RT RIC 125.

[0084] In some implementations, to generate AI / ML models to be deployed in the near-RT RIC 125, the non-RT RIC 115 may receive parameters or external enrichment information from an external server. Such information may be utilized by the near-RT RIC 125 and may be received from non-network data sources or from network functions at the SMO framework 105 or the non-RT RIC 115. In some examples, the non-RT RIC 115 or the near-RT RIC 125 may be configured to tune RAN behavior or performance. For example, the non-RT RIC 115 may monitor long-term trends and patterns in performance and employ AI / ML models to perform corrective actions through the SMO framework 105 (such as via reconfiguration of O1) or by creating RAN management policies (such as A1 policies).

[0085] At least one of the CU 110, DU 130, and RU 140 may be referred to as a base station 102. Thus, the base station 102 may include one or more of the CU 110, DU 130, and RU 140 (each component is indicated by a dashed line to indicate that each component may or may not be included in the base station 102). The base station 102 provides an access point to the core network 120 for the UE 104. The base station 102 may include a macro cell (a high-power cellular base station) and / or a small cell (a low-power cellular base station). Small cells include femto cells, pico cells, and micro cells. A network that includes both small cells and macro cells may be referred to as a heterogeneous network. A heterogeneous network may also include a home evolved Node B (eNB) (HeNB), which may provide services to a restricted group called a closed subscriber group (CSG). The communication link between a RU (e.g., RU 140) and a UE (e.g., UE 104) may include uplink (UL) (also known as reverse link) transmissions from UE 104 to RU 140 and / or downlink (DL) (also known as forward link) transmissions from RU 140 to UE 104. The communication link may utilize multiple-input multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and / or transmit diversity. The communication link may be over one or more carriers. For each carrier allocated in a carrier aggregation for a total of up to Yx MHz (x component carriers) for transmission in each direction, base station 102 / UE 104 may utilize spectrum with a bandwidth of up to Y MHz (e.g., 5 MHz, 10 MHz, 15 MHz, 20 MHz, 100 MHz, 400 MHz, etc.). The carriers may or may not be adjacent to each other. The allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL ​​compared to UL). The component carriers may include a primary component carrier and one or more secondary component carriers. The primary component carrier may be referred to as a primary cell (PCell) and the secondary component carrier may be referred to as a secondary cell (SCell).

[0086] Certain UEs may communicate with each other using device-to-device (D2D) communication (e.g., D2D communication link 158). D2D communication link 158 may use DL / UL wireless wide area network (WWAN) spectrum. D2D communication link 158 may use one or more sidelink channels, such as a physical sidelink broadcast channel (PSBCH), a physical sidelink discovery channel (PSDCH), a physical sidelink shared channel (PSSCH), and a physical sidelink control channel (PSCCH). D2D communication may be performed via a variety of wireless D2D communication systems, such as, for example, Bluetooth, Wi-Fi based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, LTE, or NR.

[0087] The wireless communication system may also include a Wi-Fi AP 150 that communicates with a UE 104 (also referred to as a Wi-Fi station (STA)) via a communication link 154, for example, in the 5 GHz unlicensed spectrum. When communicating in the unlicensed spectrum, the UE 104 / Wi-Fi AP 150 may perform a clear channel assessment (CCA) prior to communication to determine whether the channel is available.

[0088] The electromagnetic spectrum is typically subdivided into various categories, bands, channels, etc. based on frequency / wavelength. 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). Although a portion of FR1 is greater than 6 GHz, FR1 is often (interchangeably) referred to as the "sub-6 GHz" band in various documents and articles. A similar naming issue sometimes occurs with respect to FR2, which is often (interchangeably) referred to as the "millimeter wave" band in documents and articles, although it is different from the extremely high frequency (EHF) band (30 GHz - 300 GHz) identified as the "millimeter wave" band by the International Telecommunication Union (ITU).

[0089] Frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Recent 5G NR research has identified the operating bands for these mid-band frequencies as frequency range designation FR3 (7.125GHz-24.25GHz). The frequency bands falling within FR3 can inherit FR1 characteristics and / or FR2 characteristics, and therefore the features of FR1 and / or FR2 can be effectively extended to mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operation to more than 52.6GHz. For example, three higher operating bands have been identified as frequency range designations FR2-2 (52.6GHz-71GHz), FR4 (71GHz-114.25GHz), and FR5 (114.25GHz-300GHz). Each of these higher frequency bands falls within the EHF band.

[0090] In view of the above, unless otherwise specifically stated, when the term "sub-6 GHz" is used herein, it may broadly refer to frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. In addition, unless otherwise specifically stated, when the term "millimeter wave" is used herein, it may broadly refer to frequencies that may include mid-band frequencies, may be within FR2, FR4, FR2-2 and / or FR5, or may be within the EHF band.

[0091] Base station 102 and UE 104 may each include multiple antennas (such as antenna elements, antenna panels, and / or antenna arrays) to facilitate beamforming. Base station 102 may transmit beamformed signals 182 to UE 104 in one or more transmit directions. UE 104 may receive the beamformed signals from base station 102 in one or more receive directions. UE 104 may also transmit beamformed signals 184 to base station 102 in one or more transmit directions. Base station 102 may receive the beamformed signals from UE 104 in one or more receive directions. Base station 102 / UE 104 may perform beam training to determine the optimal receive direction and the optimal transmit direction for each of base station 102 / UE 104. The transmit direction and receive direction of base station 102 may be the same or different. The transmit direction and receive direction of UE 104 may be the same or different.

[0092] The base station 102 may include and / or be referred to as a gNB, a Node B, an eNB, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS), an extended service set (ESS), a transmit / receive point (TRP), a network node, a network entity, a network equipment, or some other suitable terminology. The base station 102 may be implemented as an integrated access and backhaul (IAB) node, a relay node, a sidelink node, a converged (monolithic) base station having a baseband unit (BBU) (including a CU and a DU) and a RU, or as a disaggregated base station including one or more of a CU, a DU, and / or a RU. A collection of base stations that may include disaggregated base stations and / or converged base stations may be referred to as a next generation (NG) RAN (NG-RAN).

[0093] The core network 120 may include an access and mobility management function (AMF) (e.g., AMF 161), a session management function (SMF) (e.g., SMF 162), a user plane function (UPF) (e.g., UPF 163), a unified data management (UDM) (e.g., UDM 164), one or more location servers 168, and other functional entities. The AMF 161 is a control node that handles signaling between the UE 104 and the core network 120. The AMF 161 supports registration management, connection management, mobility management, and other functions. The SMF 162 supports session management and other functions. The UPF 163 supports packet routing, packet forwarding, and other functions. The UDM 164 supports the generation of authentication and key agreement (AKA) credentials, user identity processing, access authorization, and subscription management. The one or more location servers 168 are exemplified as including a gateway mobile location center (GMLC) (e.g., GMLC 165) and a location management function (LMF) (e.g., LMF 166). However, in general, the one or more location servers 168 may include one or more location / positioning servers, which may include one or more of the GMLC 165, LMF 166, Position Determination Entity (PDE), Serving Mobile Location Center (SMLC), Mobile Positioning Center (MPC), etc. The GMLC 165 and LMF 166 support UE location services. The GMLC 165 provides an interface for clients / applications (e.g., emergency services) to access UE positioning information. The LMF 166 receives measurements and assistance information from the NG-RAN and UE 104 via the AMF 161 to calculate the location of the UE 104. The NG-RAN may utilize one or more positioning methods to determine the location of the UE 104. Positioning the UE 104 may involve signal measurements, position estimation, and optional velocity calculation based on these measurements. Signal measurements may be performed by the UE 104 and / or a serving base station (e.g., base station 102). The measured signals may be based on one or more of a satellite positioning system (SPS) 170 (e.g., a global navigation satellite system (GNSS), a global positioning system (GPS), a non-terrestrial network (NTN), or other satellite positioning / positioning systems), LTE signals, wireless local area network (WLAN) signals, Bluetooth signals, a terrestrial beacon system (TBS), sensor-based information (e.g., an atmospheric pressure sensor, a motion sensor), an NR enhanced cell ID (NR E-CID) method, NR signals (e.g., multi-round trip time (multi-RTT), DL angle of departure (DL-AoD), DL time difference of arrival (DL-TDOA), UL time difference of arrival (UL-TDOA), and UL angle of arrival (UL-AoA) positioning), and / or other systems / signals / sensors.

[0094] Examples of UEs include cellular phones, smartphones, Session Initiation Protocol (SIP) phones, laptops, personal digital assistants (PDAs), satellite radios, global positioning systems, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, tablets, smart devices, wearable devices, vehicles, electric meters, gas pumps, large or small kitchen appliances, healthcare equipment, implants, sensors / actuators, displays, or any other similarly functional device. Some of the UEs may be referred to as IoT devices (e.g., parking meters, gas pumps, toasters, vehicles, heart monitors, etc.). UE 104 may also be referred to as a station, mobile station, subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable term. In some scenarios, the term UE may also apply to one or more supporting devices, such as in a device cluster arrangement. One or more of these devices may access the network collectively and / or individually.

[0095] Reference again Figure 1 In certain aspects, a device (such as UE 104) communicating with a base station may be configured to manage one or more aspects of wireless communication by facilitating precoding for 8Tx. For example, UE 104 may include a codebook processing component 198 configured to: receive control signaling for an uplink MIMO transmission, the control signaling including a first TPMI field and a second TPMI field and an SRS resource set indicator; and transmit an uplink MIMO transmission precoded with an 8-port uplink MIMO precoder based on a 4-port uplink MIMO codebook and a mapping indicated by one or more of the first TPMI field, the second TPMI field, or the SRS resource set indicator. In some aspects, codebook processing component 198 may be configured to: receive control signaling for an UL MIMO transmission; and transmit an UL MIMO transmission precoded with the 8-port uplink MIMO precoder based on the control signaling and a set of two or more antenna port groups.

[0096] In another configuration, the base station 102 may include a codebook signaling component 199 configured to: output control signaling for an uplink MIMO transmission for transmission, the control signaling including a first TPMI field and a second TPMI field and an SRS resource set indicator; and receive an uplink MIMO transmission pre-coded with an 8-port uplink MIMO pre-coder based on a 4-port uplink MIMO codebook and a mapping indicated by one or more of the first TPMI field, the second TPMI field, or the SRS resource set indicator. In some aspects, the codebook signaling component 199 may be configured to: output control signaling for an UL MIMO transmission for transmission; and obtain the UL MIMO transmission pre-coded with the 8-port uplink MIMO pre-coder based on the control signaling and a set of two or more antenna port groups.

[0097] Although the following description provides examples involving 5G / NR (and specifically, involving 8Tx transmissions), the concepts described herein may be applicable to other similar areas where a UE may transmit 8Tx transmissions, such as LTE, LTE-A, CDMA, GSM, and / or other wireless technologies.

[0098] Figure 2A FIG200 is a diagram illustrating an example of a first subframe within a 5G NR frame structure. Figure 2B FIG230 is a diagram illustrating an example of DL channels within a 5G NR subframe. Figure 2C is a diagram 250 illustrating an example of a second subframe within a 5G NR frame structure. Figure 2D FIG280 is a diagram illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure may be frequency division duplex (FDD) (wherein, for a particular set of subcarriers (carrier system bandwidth), subframes within that subcarrier set are dedicated to either DL or UL), or may be time division duplex (TDD) (wherein, for a particular set of subcarriers (carrier system bandwidth), subframes within that subcarrier set are dedicated to both DL and UL). Figure 2A 、 Figure 2CIn the example provided, the 5G NR frame structure is assumed to be TDD, where subframe 4 is configured with slot format 28 (most of which are DL), where D is DL, U is UL, and F is flexible between DL / UL, and subframe 3 is configured with slot format 1 (all of which are UL). Although subframes 3 and 4 are shown as having slot formats 1 and 28, respectively, any particular subframe can be configured with any of the various available slot formats 0-61. Slot formats 0 and 1 are both DL and UL, respectively. Other slot formats 2-61 include a mix of DL, UL, and flexible symbols. The slot format is configured for the UE via the received slot format indicator (SFI) (dynamically configured via DL control information (DCI) or semi-statically / statically configured via radio resource control (RRC) signaling). Note that the following description also applies to the 5G NR frame structure for TDD.

[0099] Figures 2A to 2D The frame structure is illustrated, and various aspects of the present disclosure are applicable to other wireless communication technologies that may have different frame structures and / or different channels. A frame (10ms) can be divided into 10 equally sized subframes (1ms). Each subframe may include one or more time slots. A subframe may also include mini-time slots, which may include 7, 4, or 2 symbols. Each time slot may include 14 or 12 symbols, depending on whether the cyclic prefix (CP) is normal or extended. For a normal CP, each time slot may include 14 symbols, and for an extended CP, each time slot may include 12 symbols. The symbols on the DL may be CP orthogonal frequency division multiplexing (OFDM) (CP-OFDM) symbols. The symbols on the UL may be CP-OFDM symbols (for high throughput scenarios) or discrete Fourier transform (DFT) spread OFDM (DFT-s-OFDM) symbols (also known as single carrier frequency division multiple access (SC-FDMA) symbols) (for power-limited scenarios; limited to single-stream transmission). The number of time slots within a subframe is based on the CP and parameter set. The parameter set defines the subcarrier spacing (SCS) and effectively defines the symbol length / duration, which is equal to 1 / SCS.

[0100]

[0101] For normal CP (14 symbols / slot), different parameter sets μ0 to 4 allow 1, 2, 4, 8, and 16 slots per subframe, respectively. For extended CP, parameter set 2 allows 4 slots per subframe. Accordingly, for normal CP and parameter set μ, there are 14 symbols / slot and 2 μ time slots / subframe. The subcarrier spacing can be equal to 2 μ*15kHz, where μ is parameter set 0 to 4. Therefore, the subcarrier spacing for parameter set μ=0 is 15kHz, and the subcarrier spacing for parameter set μ=4 is 240kHz. Symbol length / duration is inversely related to subcarrier spacing. Figures 2A to 2D An example is provided for a normal CP with 14 symbols per slot and a parameter set μ=2 with 4 slots per subframe. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs. Within a frame set, there may be one or more different bandwidth parts (BWPs) that are frequency-division multiplexed (see Figure 2B ). Each BWP may have a specific parameter set and CP (normal or extended).

[0102] The resource grid can be used to represent the frame structure. Each time slot includes a resource block (RB) (also known as a physical RB (PRB)) extending over 12 consecutive subcarriers. The resource grid is divided into multiple resource elements (REs). The number of bits carried by each RE depends on the modulation scheme.

[0103] like Figure 2A As illustrated, some of the REs carry reference (pilot) signals (RS) for the UE. The RSs may include demodulation RSs (DM-RSs) (indicated as R for a specific configuration, but other DM-RS configurations are possible) and channel state information reference signals (CSI-RSs) for channel estimation at the UE. The RSs may also include beamforming RSs (BRSs), beam refinement RSs (BRRSs), and phase tracking RSs (PT-RSs).

[0104] Figure 2BExamples of various DL channels within a subframe of a frame are illustrated. The physical downlink control channel (PDCCH) carries DCI within one or more control channel elements (CCEs) (e.g., 1, 2, 4, 8, or 16 CCEs), each CCE comprising six RE groups (REGs), each REG comprising 12 consecutive REs within an OFDM symbol of a RB. The PDCCH within a BWP may be referred to as a control resource set (CORESET). During a PDCCH monitoring opportunity on the CORESET, the UE is configured to monitor PDCCH candidates in a PDCCH search space (e.g., a common search space, a UE-specific search space), where the PDCCH candidates have different DCI formats and different aggregation levels. Additional BWPs may be located at higher and / or lower frequencies across the channel bandwidth. The primary synchronization signal (PSS) may be within symbol 2 of a specific subframe of a frame. The PSS is used by UE 104 to determine subframe / symbol timing and physical layer identification. The secondary synchronization signal (SSS) may be within symbol 4 of a specific subframe of a frame. The SSS is used by the UE to determine the physical layer cell identity group number and radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE can determine the physical cell identifier (PCI). Based on the PCI, the UE can determine the location of the DM-RS. The physical broadcast channel (PBCH) carrying the master information block (MIB) can be logically grouped with the PSS and SSS to form a synchronization signal (SS) / PBCH block (also known as an SS block (SSB)). The MIB provides the number of RBs in the system bandwidth and the system frame number (SFN). The physical downlink shared channel (PDSCH) carries user data, broadcast system information not sent over the PBCH (such as the system information block (SIB)), and paging messages.

[0105] like Figure 2C As illustrated, some of the REs carry DM-RS (indicated as R for a specific configuration, but other DM-RS configurations are possible) for channel estimation at the base station. The UE may transmit the DM-RS of the physical uplink control channel (PUCCH) and the DM-RS of the physical uplink shared channel (PUSCH). The PUSCH DM-RS may be transmitted in the first or first two symbols of the PUSCH. Depending on whether a short PUCCH or a long PUCCH is transmitted and depending on the specific PUCCH format used, the PUCCH DM-RS may be transmitted in different configurations. The UE may transmit a sounding reference signal (SRS). The SRS may be transmitted in the last symbol of the subframe. The SRS may have a comb structure, and the UE may transmit the SRS on one of the teeth of the comb. The SRS may be used by the base station for channel quality estimation to achieve frequency-dependent scheduling of the UL.

[0106] Figure 2DExamples of various UL channels within a subframe of a frame are illustrated. The PUCCH may be located at a position as indicated in one configuration. The PUCCH carries uplink control information (UCI), such as a scheduling request, a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), and hybrid automatic repeat request (HARQ) acknowledgement (ACK) (HARQ-ACK) feedback (i.e., one or more HARQ ACK bits indicating one or more ACKs and / or negative ACKs (NACKs)). The PUSCH carries data and may additionally be used to carry a buffer status report (BSR), a power headroom report (PHR), and / or UCI.

[0107] Figure 3 is a block diagram illustrating an example of a first wireless device configured to exchange wireless communications with a second wireless device. Figure 3 In the illustrated example of FIG, the first wireless device may include a base station 310, the second wireless device may include a UE 350, and the base station 310 may communicate with the UE 350 in an access network. Figure 3 As shown, base station 310 includes a transmit processor (TX processor 316), a transmitter 318Tx, a receiver 318Rx, antennas 320, a receive processor (RX processor 370), a channel estimator 374, a controller / processor 375, and a memory 376. Example UE 350 includes antennas 352, a transmitter 354Tx, a receiver 354Rx, an RX processor 356, a channel estimator 358, a controller / processor 359, a memory 360, and a TX processor 368. In other examples, base station 310 and / or UE 350 may include additional or alternative components.

[0108] In the DL, Internet Protocol (IP) packets may be provided to the controller / processor 375. The controller / processor 375 implements layer 3 and layer 2 functionality. Layer 3 includes the radio resource control (RRC) layer, and layer 2 includes the service data adaptation protocol (SDAP) layer, the packet data convergence protocol (PDCP) layer, the radio link control (RLC) layer, and the medium access control (MAC) layer. The controller / processor 375 provides RRC layer functionality associated with broadcasting of system information (e.g., MIB, SIB), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-radio access technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression / decompression, security (ciphering, deciphering, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with delivery of upper layer packet data units (PDUs), error correction through ARQ, concatenation, segmentation and reassembly of RLC service data units (SDUs), resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

[0109] The TX processor 316 and the RX processor 370 implement Layer 1 functionality associated with various signal processing functions. Layer 1, which includes the physical (PHY) layer, may include error detection on the transport channel, forward error correction (FEC) coding / decoding of the transport channel, interleaving, rate matching, mapping onto the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. The TX processor 316 handles the mapping onto signal constellations based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-order phase shift keying (M-PSK), and M-order quadrature amplitude modulation (M-QAM)). The coded and modulated symbols are then separated into parallel streams. Each stream is then mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., a pilot) in the time and / or frequency domain, and then combined using an inverse fast Fourier transform (IFFT) to produce a physical channel carrying a time-domain OFDM symbol stream. The OFDM stream is spatially precoded to generate multiple spatial streams. Channel estimates from a channel estimator 374 may be used to determine the coding and modulation schemes and for spatial processing. The channel estimates may be derived from a reference signal and / or channel condition feedback transmitted by the UE 350. Each spatial stream may then be provided to a different one of the antennas 320 via a separate transmitter (e.g., transmitter 318Tx). Each transmitter 318Tx may modulate a radio frequency (RF) carrier with a corresponding spatial stream for transmission.

[0110] At the UE 350, each receiver 354Rx receives a signal via its corresponding antenna in the antennas 352. Each receiver 354Rx recovers the information modulated onto the RF carrier and provides the information to the RX processor 356. The TX processor 368 and the RX processor 356 implement Layer 1 functionality associated with various signal processing functions. The RX processor 356 may perform spatial processing on the information to recover any spatial streams destined for the UE 350. In the event that multiple spatial streams are destined for the UE 350, two or more of the multiple spatial streams may be combined by the RX processor 356 into a single OFDM symbol stream. The RX processor 356 then converts the OFDM symbol stream from the time domain to the frequency domain using a Fast Fourier Transform (FFT). The frequency-domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, as well as the reference signal, are recovered and demodulated by determining the signal constellation point most likely transmitted by the base station 310. These soft decisions may be based on channel estimates calculated by the channel estimator 358. The soft decisions are then decoded and deinterleaved to recover the data and control signals originally sent on the physical channel by base station 310. The data and control signals are then provided to a controller / processor 359, which implements layer 3 and layer 2 functionality.

[0111] The controller / processor 359 may be associated with a memory 360 that stores program codes and data. The memory 360 may be referred to as a computer-readable medium. In the UL, the controller / processor 359 provides demultiplexing between transport and logical channels, packet reassembly, decryption, header decompression, and control signal processing to recover IP packets. The controller / processor 359 is also responsible for error detection using an ACK and / or NACK protocol to support HARQ operations.

[0112] Similar to the functionality described in conjunction with DL transmissions performed by the base station 310, the controller / processor 359 provides RRC layer functionality associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functionality associated with header compression / decompression and security (encryption, decryption, integrity protection, integrity verification); RLC layer functionality associated with delivery of upper layer PDUs, error correction through ARQ, concatenation, segmentation and reassembly of RLC SDUs, resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

[0113] Channel estimates derived by the channel estimator 358 from a reference signal or feedback sent by the base station 310 may be used by the TX processor 368 to select appropriate coding and modulation schemes and to facilitate spatial processing. The spatial streams generated by the TX processor 368 may be provided to different ones of the antennas 352 via separate transmitters (e.g., transmitter 354Tx). Each transmitter 354Tx may modulate an RF carrier with a corresponding spatial stream for transmission.

[0114] UL transmissions are processed at the base station 310 in a manner similar to that described in conjunction with the receiver functionality at the UE 350. Each receiver 318Rx receives a signal through its corresponding one of the antennas 320. Each receiver 318Rx recovers information modulated onto an RF carrier and provides the information to the RX processor 370.

[0115] The controller / processor 375 may be associated with a memory 376 that stores program codes and data. The memory 376 may be referred to as a computer-readable medium. In the UL, the controller / processor 375 provides demultiplexing between transport and logical channels, packet reassembly, decryption, header decompression, and control signal processing to recover IP packets. The controller / processor 375 is also responsible for error detection using an ACK and / or NACK protocol to support HARQ operations.

[0116] At least one of the TX processor 368, the RX processor 356, and the controller / processor 359 may be configured to combine Figure 1 Codebook processing The codebook processing component 198 performs various aspects.

[0117] At least one of the TX processor 316, the RX processor 370, and the controller / processor 375 may be configured to combine Figure 1 The codebook signaling component 199 performs various aspects.

[0118] Figure 4 An example UE 400 is illustrated in communication with a network node 450 as presented herein. The UE 400 may be similar to Figure 4 UE 104, and / or Figure 3 The network node 450 may be similar to the base station 102 or a component of the base station 102, such as Figure 1 CU 110, DU 130 and / or RU 140 of.

[0119] Example UE 400 includes eight antenna elements (e.g., first antenna element 402a, second antenna element 402b, third antenna element 402c, fourth antenna element 402d, fifth antenna element 402e, sixth antenna element 402f, seventh antenna element 402g, and eighth antenna element 402h). Antenna elements may be collectively referred to herein as "antenna elements 402." Antenna elements may be referred to as antennas, antenna ports, or ports. Although example UE 400 is illustrated as having eight antenna elements, in other examples, the UE may include fewer or more antenna elements.

[0120] exist Figure 4 In the illustrated example of , antenna elements 402 are located on different parts of UE 400, thereby creating diversity and providing directional communication. UE 400 may use at least one of antenna elements 402 to transmit a communication signal (e.g., an SRS signal) to enable network node 450 to estimate an uplink channel. UE 400 includes a baseband 404 and a transmit path 406 for uplink transmission using one or more of antenna elements 402. Aspects of baseband 404 may be provided by Figure 3350 is implemented by the TX processor 368 and / or processor 359 of the UE 350. The transmit path 406 includes eight example transmit chains (e.g., a first transmit chain 408a, a second transmit chain 408b, a third transmit chain 408c, a fourth transmit chain 408d, a fifth transmit chain 408e, a sixth transmit chain 408f, a seventh transmit chain 408g, and an eighth transmit chain 408h). The transmit chains may also be referred to as RF chains. The transmit chains of the UE 400 may be collectively referred to herein as "transmit chains 408." Although the example UE 400 is illustrated as having eight transmit chains, in other examples, the UE may include fewer or more transmit chains. Each transmit chain may be configured to convert a baseband signal into an RF signal for transmission.

[0121] UE 400 can detect the port by transmitting SRS using a combination of transmission chains. Figure 4 In the example of FIG, UE 400 includes eight example ports (eg, first port 410a, second port 410b, third port 410c, fourth port 410d, fifth port 410e, sixth port 410f, seventh port 410g, and eighth port 410h). The ports may be collectively referred to herein as "ports 410."

[0122] Ports 410 may or may not have a one-to-one mapping to antenna elements 402. When there is a one-to-one mapping, each of antenna elements 402 may be mapped to one of ports 410. UE 400 may report the complex of signals from transmit chain 408 as a virtual port to network node 450 by applying TPMI precoder 412. Although TPMI precoder 412 is illustrated with respect to transmit chain 408, TPMI precoder 412 may be applied to baseband 404.

[0123] The UE 400 can support three levels of coherence: full coherence, partial coherence, and incoherence. A UE with full coherence can be referred to as a fully coherent UE and can transmit coherently across all antenna elements 402. A fully coherent UE has the ability to control the relative phase between the transmit chains 408 of the UE 400. The two antenna elements maintain relative phase when the phase across the two antennas is locked and / or remains the same across the uplink transmission.

[0124] A UE with partial coherence may be referred to as a partially coherent UE and may transmit coherently on antenna element pairs. A partially coherent UE has the ability to maintain relative phase across multiple subsets of antenna elements 402. For example, a first coherent antenna pair 414 may include a first antenna element 402a and a fourth antenna element 402d, and a second coherent antenna pair 416 may include a second antenna element 402b and a third antenna element 402c. The antenna elements of the respective coherent antenna pairs may be coherent antennas relative to each other and may maintain relative phase across the two respective antenna elements. However, a partially coherent UE may not be able to maintain phase coherence across the two pairs.

[0125] A UE with non-coherence may be referred to as a non-coherent UE and may be unable to transmit coherently through any pair or set of antenna elements. For example, a non-coherent UE may lack the ability to maintain relative phase across any of the antenna elements 402.

[0126] exist Figure 4 In the example of , UE 400 may support multi-layer uplink transmission. For non-coherent UEs, each layer of multi-layer uplink transmission is transmitted to a single antenna element in antenna elements 402, and there is no combining across layers. For partially coherent UEs, certain antenna elements are combined and each layer is transmitted to multiple ports. The partially coherent UE may be configured as a partially coherent 2Tx (PC-2) UE or a partially coherent 4Tx (PC-4) UE. For a PC-2 UE, each layer of uplink transmission is transmitted to two antenna elements in antenna elements 402, and for a PC-4 UE, each layer of uplink transmission is transmitted to four antenna elements in antenna elements 402. For a fully coherent UE, each layer is transmitted to each antenna element in antenna elements 402.

[0127] The UE 400 may be configured to apply a precoder across all subbands transmitted on the uplink, or may be configured to apply multiple precoders for multiple subbands transmitted on the uplink. The network node 450 may configure one or more precoder configurations to the UE 400. Additionally or alternatively, the network node 450 may activate the precoder configuration at the UE 400. The UE 400 may receive the precoder configuration via RRC signaling, downlink control information (DCI), and / or a MAC control element (MAC-CE).

[0128] Figure 5 An example communication flow 500 between a network node 502 and a UE 504 as presented herein is illustrated. Aspects of the network node 502 may be implemented by Figure 1 Base station 102, Figure 3 Base station 310, and / or Figure 4One or more aspects described with respect to the network node 502 may be performed by a base station or a component of a network entity such as a CU, DU, and / or RU. Figure 1 UE 104, Figure 3 UE 350, and / or Figure 4 UE 400 to achieve. Figure 5 Not shown in the illustrated example, it will be appreciated that in additional or alternative examples, network node 502 may communicate with one or more other network nodes or UEs, and / or UE 504 may communicate with one or more other network nodes or UEs.

[0129] In the illustrated example, communication flow 500 facilitates codebook and control signaling for 8Tx uplink MIMO transmission at UE 504. Communication flow 500 may utilize an 8Tx codebook design for ranks 5 to 8. Control signaling may facilitate signaling a transmit precoding matrix index (TPMI) field and rank information. Control signaling may indicate an 8Tx precoding matrix for ranks 1 to 8. Example communication flow 500 may also facilitate dynamic switching between non-coherent precoding, partially coherent precoding, and fully coherent precoding. In some examples, control signaling may reuse a 4Tx codebook and TPMI field for the 8Tx codebook.

[0130] like Figure 5 As shown, network node 502 may output an RRC configuration 510, which is received by UE 504. Network node 502 may output RRC configuration 510 via RRC signaling. RRC configuration 510 may configure one or more parameters associated with transmitting uplink transmissions to UE 504. For example, RRC configuration 510 may identify one or more sounding reference signal (SRS) resources.

[0131] UE 504 may transmit an SRS 520, which may be received by network node 502. SRS 520 may be associated with one or more transmit ports of UE 504, such as Figure 4 Although the example UE 504 transmits SRS, in other examples, the UE 504 may transmit any other reference signal that may enable a network node to estimate channel conditions between the UE 504 and the network node 502.

[0132] exist Figure 5 In the example of FIG5 , the network node 502 uses the SRS 520 to generate an uplink channel estimate 530. The network node 502 may then select a precoding matrix 532 based on the uplink channel estimate 530. The network node 502 may also select a transmit precoding matrix index 534 (TPMI) from the Tx codebook based on the precoding matrix 532.

[0133] like Figure 5 As shown, network node 502 sends control signaling 540, which is received by UE 504. Network node 502 may send control signaling 540 via DCI. UE 504 determines a precoding matrix 550 based on control signaling 540. UE 504 may then use precoding matrix 550 to send an uplink transmission 560.

[0134] For multi-TRP (M-TRP) PUSCH repetition, two SRS resource sets may be configured for the UE 504. One or more SRS resource perf sets may also be configured for the UE 504. It may not be desirable to configure the UE 504 with different numbers of SRS resources in the two SRS resource sets. Additionally, when two SRS resources are indicated, the "nrofSRS-Ports" parameter for the two indicated SRS resources may be the same.

[0135] exist Figure 5 In the example of FIG, the control signaling 540 includes an SRS resource set indicator 590, a first SRS resource indicator (e.g., a first SRI field 592), a first TPMI field 594, a second SRI field 596, and a second TPMI field 598. The SRS resource set indicator 590 may be a 2-bit field and indicates how the SRI field and the TPMI field are associated with the corresponding SRS resource set. Figure 6 Depicted is a table 600 illustrating an example mapping of the SRS resource set indicator 590 to the SRI field and the TPMI field. Based on the bit fields mapped to the index, the SRI field and the TPMI field may be used for M-TRP PUSCH repetition.

[0136] The first TPMI field 594 may have a size of 6 bits and indicate a rank and a precoding matrix indication. The first TPMI field 594 may indicate the rank and precoding matrix for the first repetition set. The second TPMI field 598 may have a size of 5 bits and indicate a precoding matrix indication for the second repetition set. The second TPMI field 598 may not indicate a rank. Instead, the rank indicated from the first TPMI field 594 may be used for the second repetition set. As used herein, the term "rank" may also be used to refer to a "layer."

[0137] Figure 7 A table 700 is depicted that maps the value of the first TPMI field 594 to the rank and precoding matrix for the first repetition set to facilitate uplink 4Tx MIMO. Figure 7 In the examples, the maximum rank is 2, 3, or 4.

[0138] Figure 8A table 800 is depicted that maps the value of the second TPMI field 598 to a precoding matrix for a second repetition set to facilitate uplink 4Tx MIMO. Figure 8 In the examples, the maximum rank is 2, 3, or 4.

[0139] exist Figure 7 and Figure 8 In the example of , the first column provides a bitfield index that maps to the rank information and the matrix. The bitfield index can be mapped to the second column, the third column, or the fourth column based on whether the codebook subset indicator (which can be called "codebookSubset" or called by any other name) indicates support for fully coherent, partially coherent, and incoherent codebooks (e.g., the bitfield index maps to the second column), indicates support for partially coherent and incoherent codebooks (e.g., the bitfield index maps to the third column), or indicates support for incoherent codebooks (e.g., the bitfield index maps to the third column). Figure 7 As shown, the bit field index column is divided into three parts: a first part 702 corresponds to a non-coherent matrix in the corresponding codebook, a second part 704 corresponds to a partially coherent matrix in the corresponding codebook, and a third part 706 corresponds to a fully coherent matrix in the corresponding codebook.

[0140] For example, the bit field index of "4" in the table of slide 6 maps to "layer 1" and the fourth matrix in the corresponding rank 1 codebook. Additionally, the indicated matrix is ​​a non-coherent matrix.

[0141] Figures 9 to 12 This table lists codebook subsets that can be used in different scenarios and indicates the scaling factors used for power transmission. The precoder and scaling factor depend on, for example, the number of layers in the uplink transmission, the number of antenna ports of the UE, and whether transform precoding is enabled or disabled. The table includes a "TPMI index" column and a precoder matrix "W" column. The TPMI index may refer to or indicate matrix W, which may represent the precoder, and matrix W is sorted from left to right in ascending order of TPMI index. As used herein, the term "matrix" may be used interchangeably with the term "precoder."

[0142] Additionally, it may be relevant Figure 13 Example UE 1300 to discuss Figures 9 to 12 To better understand some aspects disclosed herein. Aspects of UE 1300 may be similar to Figure 4UE 400. However, while UE 400 is configured with eight antenna elements (e.g., antenna element 402), UE 1300 is configured with four antenna elements (e.g., first antenna element 1302a, second antenna element 1302b, third antenna element 1302c, and fourth antenna element 1302d). The four antenna elements of UE 1300 may be collectively referred to herein as "antenna element 1302." Similar to Figure 4 In the example of UE 1300 , the UE 1300 includes a baseband 1304 and a transmit path 1306 . Figure 13 Transmit path 1306 includes a transmit chain 1308 in conjunction with a port 1310. Port 1310 may be mapped one-to-one with antenna port 1302. Transmit path 1306 also includes a TPMI pre-decoder 1312. Aspects of baseband 1304 may be similar to baseband 404. Aspects of transmit path 1306 may be similar to transmit path 406. Aspects of chain 1308 may be similar to transmit chain 408. Aspects of port 1310 may be similar to port 410. Aspects of TPMI pre-decoder 1312 may be similar to TPMI pre-decoder 412.

[0143] In matrix W, the first row corresponds to the first antenna port of UE 1300 (e.g., first antenna element 1302a), the second row corresponds to the second antenna port of UE 1300 (e.g., second antenna element 1302b), the third row corresponds to the third antenna port of UE 1300 (e.g., third antenna element 1302c), and the fourth row corresponds to the fourth antenna port of UE 1300 (e.g., fourth antenna element 1302d). Additionally, the number of columns in matrix W corresponds to the number of layers. For example, a precoding matrix with a single column corresponds to single-layer transmission, a precoding matrix with two columns corresponds to two-layer transmission, a precoding matrix with three columns corresponds to three-layer transmission, and a precoding matrix with four columns corresponds to four-layer transmission, where the first column corresponds to the first layer, the second column corresponds to the second layer, the third column corresponds to the third layer, and the fourth column corresponds to the fourth layer. Furthermore, a first value in the matrix (e.g., "0") may indicate that the antenna element corresponding to the first value is not used for UL transmission. A second value (eg, "1") in the matrix may indicate that the antenna element corresponding to the second value is used for UL transmission.

[0144] The network node may select a precoding configuration based on the channel conditions of the link between the UE and the network node. The network node may additionally or alternatively select a precoding configuration based on the capabilities of the UE. For example, the precoding configuration may be based on whether the UE is a fully coherent UE, a partially coherent UE, or a non-coherent UE.

[0145] Figure 9Depicted is a table 900 storing a codebook subset of a precoding matrix W for a single layer transmission (e.g., "rank 1") for a UE with four antenna ports (e.g., "4Tx") as presented herein. Table 1900 may be used by a network node and / or a UE to employ Figure 5 Communication flow 500. Figure 9 In the example of , a scaling factor of "1 / 2" for power transmission is applied to the precoders of Table 900. Table 900 includes a non-phased precoder set 902, which includes the first four matrices of the codebook, and these four matrices are indicated by TPMI indices 0 to 3, respectively. Table 900 also includes a first partially phased precoder set 904, which includes the next four matrices of the codebook, and these four matrices are indicated by TPMI indices 4 to 7, respectively. Table 900 also includes a second partially phased precoder set 906, which includes the next four matrices of the codebook, and these four matrices are indicated by TPMI indices 8 to 11, respectively. Additionally, Table 900 includes a full phased precoder set 908, which includes the remaining sixteen matrices, and these sixteen matrices are indicated by TPMI indices 12 to 27.

[0146] Reference again Figure 7 For example, the bit field index "4" maps to "layer 1" and the fourth matrix in the corresponding rank 1 codebook. Therefore, the bit field index of "4" in Slide 6 maps to Figure 9 Matrix 910.

[0147] Figure 10 Depicted is a table 1000 storing a codebook subset of a precoding matrix W for two-layer transmission for a UE with four antenna ports as presented herein. Table 1000 may be used by a network node and / or a UE to employ Figure 5 Communication flow 500. In table 1000, the number of transmit ports is four (eg, "4Tx"), and the number of layers used for PUSCH is two (eg, "Rank 2").

[0148] Table 1000 includes a non-phased intercoder set 1002, which includes the first six matrices of the codebook, and these six matrices are respectively indicated by TPMI indices 0 to 5. Table 1000 also includes a partially phased intercoder set 1004, which includes the next eight matrices of the codebook, and these eight matrices are respectively indicated by TPMI indices 6 to 13. Additionally, table 1000 includes a fully phased intercoder set 1006, which includes the remaining eight matrices, and these eight matrices are respectively indicated by TPMI indices 14 to 21.

[0149] exist Figure 10In the example of FIG. 1 , for the pre-decoders of the non-interfered pre-decoder set 1002 and the pre-decoders of the partially interfered pre-decoder set 1204, the scaling factor for power transmission is "1 / 2". For the pre-decoders of the fully interfered pre-decoder set 1006, the scaling factor power transmission is

[0150] Figure 11 Depicted is a table 1100 storing a codebook subset of a precoding matrix W for three-layer transmission for a UE with four antenna ports as presented herein. Table 1100 may be used by a network node and / or a UE to employ Figure 5 Communication flow 500. In table 1100, the number of transmit ports is four (eg, "4Tx"), and the number of layers used for PUSCH is three (eg, "Rank 3").

[0151] Table 1100 includes a non-phased intercoder set 1102, which includes one matrix of the codebook and is indicated by TPMI index 0. Table 100 also includes a partially phased intercoder set 1104, which includes the next two matrices of the codebook and is indicated by TPMI indices 1 and 2, respectively. Additionally, table 100 includes a fully phased intercoder set 106, which includes the remaining four matrices and is indicated by TPMI indices 3 to 6.

[0152] exist Figure 1 In the example of FIG. 1 , for the pre-decoders of the non-interfered pre-decoder set 1102 and the pre-decoders of the partially interfered pre-decoder set 1104, the scaling factor for power transmission is “1 / 2”. For the pre-decoders of the fully interfered pre-decoder set 106, the scaling factor power transmission is

[0153] Figure 12 Depicted is a table 1200 storing a codebook subset of a precoding matrix W for four-layer transmission for a UE with four antenna ports as presented herein. Table 1200 may be used by a network node and / or a UE to employ Figure 5 Communication flow 500. In table 1200, the number of transmit ports is four (eg, "4Tx"), and the number of layers used for PUSCH is four (eg, "Rank 4").

[0154] Table 1200 includes a non-phased intercoder set 1202, which includes one matrix of the codebook and is indicated by TPMI index 0. Table 1200 also includes a partially phased intercoder set 1204, which includes the next two matrices of the codebook and is indicated by TPMI indices 1 and 2, respectively. Additionally, table 1200 includes a fully phased intercoder set 1206, which includes the remaining two matrices and is indicated by TPMI indices 3 and 4.

[0155] exist Figure 12 In the example of FIG. 1 , for the pre-decoders of the non-interleaved pre-decoder set 1202, the scaling factor for power transmission is “1 / 2”. For the pre-decoders of the fully interleaved pre-decoder set 1204, the scaling factor for power transmission is For the pre-decoders of the full phase interleaving decoder set 1206, the scaling factor power transmission is "1 / 4".

[0156] As wireless communication technology evolves, additional types of UEs may be supported, generally referred to herein as "advanced UEs." Advanced UEs may include smartphones, indoor customer premises equipment (CPE), outdoor CPE, laptops, etc. Advanced UEs may be associated with higher reliability and / or improved efficiency compared to non-advanced UEs. Advanced UEs may include more than four antennas, such as Figure 4 UE 400 may have eight antenna elements. Advanced UEs may additionally or alternatively have more relevant power constraints. Additionally, advanced UEs may support more than four downlink layers and / or four uplink transmit ports. Advanced UEs may also support new DMRS, SRS, and / or codebook designs.

[0157] As an increased number of transmit antennas (Tx) (e.g., greater than four transmit antennas) is considered for advanced UEs (e.g., mobile devices, larger size devices, etc.) utilizing 5G technology, support for 8-port uplink transmission may be beneficial for improving 5G performance.

[0158] For 8-port uplink transmissions, a new codebook for precoding and related precoding scheduling information in DCI can be utilized. A first type of codebook can be used for uplink transmissions with precoding disabled. This codebook can use a new design for 8 ports. Additionally, the new design can be used for ranks 5 to 8 (e.g., five-layer, six-layer, seven-layer, or eight-layer uplink transmissions). A second type of codebook can be used for uplink transmissions with precoding enabled. This codebook can use a new design for 8 ports.

[0159] Therefore, it can be understood that 8Tx uplink MIMO can adopt 8Tx uplink operation supporting four or more layers per UE in uplink transmission. To achieve 8Tx uplink operation, the uplink DMRS, SRS, SRS resource indicator (SRI) and / or TPMI (including codebook) can be updated.

[0160] Aspects disclosed herein facilitate 8Tx uplink MIMO. Example techniques include reusing a 4Tx codebook and / or TPMI table, generating a new 8Tx codebook, and control signaling to indicate to the UE the precoder to use when employing 8Tx uplink MIMO.

[0161] It is understood that there are two PUSCH repetition sets. The first repetition set will use Figure 7 Table 700, and the second repetition set will use Figure 8 Table 800. These tables support 4Tx. However, aspects disclosed herein facilitate support for 8Tx MIMO.

[0162] In a first example, aspects disclosed herein reuse a 4Tx codebook for 8Tx (e.g., Figures 9 to 12 ) and TPMI tables (e.g., Figure 7 and Figure 8 TPMI table). Figure 4 As described for the UE 400 of FIG400 , the precoder for the 8Tx UE may include a non-coherent (NC) codebook, a partially coherent codebook (PC-2) for two ports, and a partially coherent codebook (PC-4) for four ports. When mapping the coherence from the 4Tx codebook to the 8Tx codebook, the 4Tx NC codebook is mapped to the 8Tx NC codebook, the 4T PC codebook is mapped to the 8Tx PC-2 codebook, and the 4Tx fully coherent codebook is mapped to the 8Tx PC-4 codebook.

[0163] Figure 14 Depicted is a table 1400 including example 8Tx precoding matrix types for ranks 1 through 8 as presented herein. Figure 14 In the example, the 8Tx pre-coding matrix type is based on reuse combined Figures 9 to 12 For example, the rank 1 pre-coding matrix 1402 can reuse the rank 1 4Tx pre-coding matrix. Figure 14 As shown, the 4Tx rank 1 pre-decoding matrix (“W 4Tx,r＝1 ”) can be associated with the first four antenna elements of an 8Tx UE (e.g., “Type 1”) or the last four antenna elements of an 8Tx UE (e.g., “Type 2”).

[0164] like Figure 14As shown, the rank 2 precoding matrix 1404 can be configured in three different types. Similar to the example of the rank 1 precoding matrix 1402, the rank 2 precoding matrix 1404 includes two types, wherein the corresponding 4Tx matrix (e.g., “W 4Tx，r＝2 ”) is associated with the first four antenna elements of an 8Tx UE (e.g., “Type 1”) or the last four antenna elements of an 8Tx UE (e.g., “Type 2”). The rank 2 precoding matrix 1404 also includes a third type (e.g., “Type 3”) in which the first layer uses the first 4Tx rank 1 precoding matrix (“W 4Tx，r＝1 ”), and the second layer uses the second 4Tx rank 1 precoding matrix (“W′ 4Tx，r＝1 ”).

[0165] Similar to the examples of rank 1 precoding matrix 1402 and rank 2 precoding matrix 1404, rank 3 precoding matrix 1406 and rank 4 precoding matrix 1408 each include a type of using the corresponding 4Tx precoding matrix in the first four antenna elements of an 8Tx UE (e.g., "Type 1") or the last four antenna elements of an 8Tx UE (e.g., "Type 2").

[0166] It is understood that the rank 3 precoding matrix includes three layers. The example rank 3 precoding matrix 1406 includes two additional types of 4Tx precoding matrices with lower ranks for different layers. For example, the rank 3 precoding matrix 1406 of "type 3" can be used to convert the 4Tx rank 2 precoding matrix ("W 4Tx，r＝2 ”) is used for the first four antenna elements of the 8Tx UE in the first and second layers, and the 4Tx rank 1 precoding matrix (“W 4Tx，r＝ 1”) is used for the last four antenna elements of the 8Tx UE on the third layer. The rank 3 precoding matrix 1406 of “Type 4” can be used to convert the 4Tx rank 1 precoding matrix (“W 4Tx，r＝ 1”) is used for the first four antenna elements of the 8Tx UE in the first layer, and the 4Tx rank 2 precoding matrix (“W 4Tx，r＝2 ”) The last four antenna elements of the 8Tx UE for the second and third layers.

[0167] like Figure 14As shown, the rank 4 precoding matrix 1408 includes five different types, where the different types utilize different combinations of 4Tx precoding matrix ranks at different layers. The rank 5 precoding matrix 1410 includes four different types, where the different types utilize different combinations of 4Tx precoding matrix ranks at different layers. The rank 6 precoding matrix 1412 includes three different types, where the different types utilize different combinations of 4Tx precoding matrix ranks at different layers. The rank 7 precoding matrix 1414 includes two different types, where the different types utilize different combinations of 4Tx precoding matrix ranks at different layers. The rank 8 precoding matrix 1416 includes one type, where the first 4Tx rank 4 precoding matrix (“W 4Tx，r＝4 ”) for the first four antenna elements of the 8Tx UE for the first four layers, and the second 4Tx rank 4 precoding matrix (“W′ 4Tx，r＝4 ”) is used in the last four antenna elements of the 8Tx UE in the last four layers.

[0168] As above combined Figure 5 As described, control signaling 540 to UE 504 may include an SRS resource set indicator 590, a first SRI field 592, a first TPMI field 594, a second SRI field 596, and a second TPMI field 598. Aspects disclosed herein use information provided via control signaling 540 to indicate the rank and type of the 8Tx precoding matrix.

[0169] Figure 15 1500 between a network node 1502 and a UE 1504 as presented herein. Aspects of the communication flow 1500 may be similar to Figure 5 Communication flow 500.

[0170] like Figure 15 As shown, network node 1502 outputs an RRC configuration 1510, which is received by UE 1504. Aspects of RRC configuration 1510 may be similar to Figure 5 RRC configuration 510. Figure 15 In the example of , RRC configuration 1510 includes a first SRS resource set 1512, a first SRS resource set port indicator 1514, a second SRS resource set 1516, a second SRS resource set port indicator 1518, and an 8-port uplink MIMO indicator 1520. The first SRS resource set 1512 and the second SRS resource set 1516 may indicate two SRS resource sets allocated to UE 1504. Each SRS resource set may be associated with four ports. Figure 15In the example of FIG, first SRS resource set port indicator 1514 may indicate four ports associated with the first SRS resource set, and second SRS resource set port indicator 1518 may indicate four ports associated with the second SRS resource set. 8-port uplink MIMO indicator 1520 may configure UE 1504 to use the indicated SRS resource set for 8Tx uplink transmission.

[0171] The UE 1504 may use the information provided by the RRC configuration 1510 to determine which two SRS resource sets are associated with 8-port UL MIMO (eg, based on the first SRS resource set 1512 and the second SRS resource set 1516).

[0172] The network node 1502 may output control signaling 1530, which may be received by the UE 1504. The network node 1502 may receive an SRS (e.g., in conjunction with a signaling ... Figure 5 The control signaling 1530 is then outputted as described in the example SRS 520. Aspects of the control signaling 1530 may be similar to Figure 4 The network node 1502 may provide control signaling 1530 such as DCI. Figure 15 In the example of , the control signaling 1530 includes an SRS resource set indicator 1532 , a first SRI field 1534 , a second SRI field 1536 , a first TPMI field 1538 , and a second TPMI field 1540 .

[0173] The control signaling 1530 may include a precoding matrix type indicator and a precoding matrix indicator. For example, at 1550, the UE 1504 may use the SRS resource set indicator 1532 to determine the precoding matrix type (e.g., type 1, type 2, etc.). The SRS resource set indicator 1532 may be a 2-bit field. At 1552, the UE 1504 may use two SRI fields (e.g., a first SRI field 1534 and a second SRI field 1536) to determine corresponding SRS resources within two SRS resource sets indicated by the RRC configuration 1510 (e.g., via the first SRS resource set 1512 and the second SRS resource set 1516). At 1554, the UE 1504 may use the first TPMI field 1538 to determine the rank and the first TPMI ("TPMI 1"), as combined Figure 8 As shown in the example table 800 of FIG. At 1556, UE 1504 may determine a second TPMI ("TPMI 2") using the second TPMI field 1540. Based on the information provided by RRC configuration 1510 and control signaling 1530, UE 1504 may determine the 8Tx precoding matrix. Figure 15As shown, UE 1504 may send an uplink transmission 1560, which is received by network node 1502. Figure 15 In the example of , the SRS resource set indicator 1532 , the first TPMI field 1538 , and the second TPMI field 1540 jointly specify the 8Tx precoding matrix for uplink transmission 1560 .

[0174] exist Figure 5 and Figure 9 In the example of , the precoding matrix indicated by the second TPMI field 598 of the control signaling 540 has the same rank as the precoding matrix indicated by the first TPMI field 594. Figure 15 In the example of , the rank of the second precoding matrix indicated by the second TPMI field 1540 is determined based on the type indicator and the rank indicated by the first TPMI field 1538 .

[0175] Figure 16 An example table 1600 is depicted that facilitates mapping type indicators and TPMI fields to an 8Tx precoding matrix as presented herein. The example table 1600 includes a type indicator column 1602, a first TPMI field column 1604, a second TPMI field column 1606, and an 8Tx precoding matrix column 1608. The value of the type indicator column 1602 may correspond to Figure 15 The SRS resource set indicator 1532 of the first TPMI field column 1604 may correspond to the first TPMI field 1538, and the value of the second TPMI field column 1606 may correspond to the second TPMI field 1540. Figure 16 In the example of FIG, the "TPMI 1" indication included in the first TPMI field column 1604 and / or the second TPMI field column 1606 corresponds to the precoding matrix indication for the first SRS resource set. Additionally, the "TPMI 2" indication included in the first TPMI field column 1604 and / or the second TPMI field column 1606 corresponds to the precoding matrix indication for the second SRS resource set.

[0176] exist Figure 16 In the example of Figure 16 For example, the SRS resource set indicator 1532 may be a 2-bit field, and thus, the value of the SRS resource set indicator 1532 may correspond to a value of 0, 1, 2, or 3. Figure 16 As shown in the example of , when the type indicator of the type indicator column 1602 is "0" or "1", the value of the second TPMI field column 1606 can be "reserved" or ignored when determining the 8Tx precoding matrix. Figure 14In the example table 1400, the rank 1 precoding matrix 1402, the rank 2 precoding matrix 1404, the rank 3 precoding matrix 1406, and the rank 4 precoding matrix 1408 include type 1 and type 2 references to a corresponding 4Tx precoding matrix. When the value of the type indicator column 1602 is "0", the 8Tx precoding matrix is ​​"type 1", and when the value of the type indicator column 1602 is "1", the 8Tx precoding matrix is ​​"type 2".

[0177] For example, the first row 1610 of the rank 1 type 1 precoding matrix corresponds to Figure 14 The rank 1 type 1 precoding matrix 1402 of the rank 1 precoding matrix 1402 is a rank 1 type 1 precoding matrix, which refers to the 4Tx rank 1 precoding matrix (“W 4Tx,r＝1 ”). The TPMI value of the first TPMI field 1538 may indicate that a 4Tx rank 1 codebook (eg, Figure 11 1100) for which precoding matrix to use for the 4Tx rank 1 precoding matrix (“W 4Tx,r＝1 ”). For example, in the case where the value of the first TPMI field 1538 is “4”, the UE 1504 may use the matrix 1110 of the table 1100 to fill the 4Tx rank 1 precoding matrix (“W 4Tx,r＝1 ”).

[0178] The example second row 1612 of the table 1600 includes a type indicator of "2", and the first TPMI indicates "4Tx, 1 layer, TPMI 1". Figure 16 In the example of , the type indicator of "2" and the rank 1 indication (e.g., "1 layer") via the first TPMI indicate that the rank of the second precoding matrix is ​​also rank 1 (e.g., "1 layer"). The number of layers indicated by the first TPMI and the number of layers indicated by the second TPMI correspond to the rank of the 8Tx precoding matrix.

[0179] like Figure 16 As shown in the example table 1600, not all pre-coding matrix types are supported. For example, with respect to rank 4, table 1600 supports types 1 to 3, but does not support types 4 and 5. With respect to ranks 5 to 7, corresponding type 1 is supported, but the remaining types are not supported. Therefore, it can be understood that reuse Figure 15 The two SRI fields and two TPMI fields of the control signaling 1530 may result in certain types not being represented.

[0180] Figure 17 1700 between a network node 1702 and a UE 1704 as presented herein. Aspects of the communication flow 1700 may be similar to Figure 5 Communication flow 500 and / or Figure 15 Communication flow 1500.

[0181] Similar to Figure 15 In the example of , network node 1502 outputs RRC configuration 1710, which is received by UE 1704. Figure 17 In the example of , RRC configuration 1710 includes a first SRS resource set 1712, a first SRS resource set port indicator 1714, a second SRS resource set 1716, a second SRS resource set port indicator 1718, and an 8-port uplink MIMO indicator 1720. The first SRS resource set 1712 and the second SRS resource set 1716 may indicate two SRS resource sets allocated to UE 1704. Each SRS resource set may be associated with four ports. Figure 17 In the example of FIG, first SRS resource set port indicator 1714 may indicate four ports associated with the first SRS resource set, and second SRS resource set port indicator 1718 may indicate four ports associated with the second SRS resource set. 8-port uplink MIMO indicator 1720 may configure UE 1704 to use the indicated SRS resource set for 8Tx uplink transmission.

[0182] The UE 1704 may use the information provided by the RRC configuration 1710 to determine which two SRS resource sets are associated with 8-port UL MIMO (eg, based on the first SRS resource set 1712 and the second SRS resource set 1716).

[0183] The network node 1702 may output control signaling 1730, which is received by the UE 1704. The network node 1702 may receive an SRS (e.g., in conjunction with a signaling ... Figure 5 The control signaling 1730 is then outputted as described in the example SRS 520. Aspects of the control signaling 1730 may be similar to Figure 4 The network node 1702 may provide control signaling 1730 such as DCI. Figure 15 In the example of FIG. 17 , the control signaling 1730 includes an SRS resource set indicator 1732 , a first SRI field 1734 , a second SRI field 1736 , a first TPMI field 1738 , and a second TPMI field 1740 .

[0184] exist Figure 17In the example of FIG17 , the UE 1704 may use the SRS resource set indicator 1732, the second SRI field 1736, the first TPMI field 1738, and the second TPMI field 1740 to determine the 8Tx precoding matrix to be applied for transmitting the uplink transmission 1760. For example, at 1750, the UE 1704 may use the SRS resource set indicator 1732 and the second SRI field 1736 to determine the precoding matrix type (e.g., type 1, type 2, etc.). At 1752, the UE 1704 may use the first SRI field 1734 to determine the corresponding SRS resources within the two SRS resource sets indicated by the RRC configuration 1710 (e.g., via the first SRS resource set 1712 and the second SRS resource set 1716). For example, when the first SRI field 1734 is set to "0," SRS resource 0 in the first SRS resource set as indicated by the first SRS resource set 1712 and SRS resource 0 in the second SRS resource set as indicated by the second SRS resource set 1716 are indicated SRS resources. Additionally, when the first SRI field 1734 is set to "1," SRS resource 1 in the first SRS resource set as indicated by the first SRS resource set 1712 and SRS resource 1 in the second SRS resource set and the second SRS resource set 1716 are indicated SRS resources.

[0185] At 1754, UE 1704 may use the first TPMI field 1738 to determine the rank and first TPMI ("TPMI 1"), as combined with Figure 8 As shown in the example table 800 of FIG. At 1756, UE 1704 may determine a second TPMI ("TPMI 2") using the second TPMI field 1740. Based on the information provided by RRC configuration 1710 and control signaling 1730, UE 1704 may determine the 8Tx precoding matrix. Figure 17 As shown, UE 1704 may send an uplink transmission 1760, which is received by network node 1702. UE 1704 may send uplink transmission 1760 using the determined 8Tx precoding matrix. Figure 17 In the example of , the SRS resource set indicator 1732 , the second SRI field 1736 , the first TPMI field 1538 , and the second TPMI field 1540 jointly specify an 8Tx precoding matrix for uplink transmission 1760 .

[0186] Figure 18 Depicted is a table 1800 that facilitates mapping of a type indicator, a modified SR field, and a TPMI field to an 8Tx precoding matrix as presented herein. Figure 19Depicted is a table 1900 that facilitates mapping the type indicator, modified SR field, and TPMI field to an 8Tx precoding matrix as presented herein. Figure 18 and Figure 19 The tables can be read together and illustrate the support Figure 14 All possible precoding matrix types are indicated in the example table 1400 of FIG.

[0187] Example tables 1800 and 1900 include a type indicator column 1802, a second SRI column 1804, a first TPMI field column 1806, a second TPMI field column 1808, and an 8Tx precoding matrix column 1810. The value of the type indicator column 1802 may correspond to Figure 17 The SRS resource set indicator 1732 of the second SRI column 1804 may correspond to the second SRI field 1736, the value of the first TPMI field column 1806 may correspond to the first TPMI field 1738, and the value of the second TPMI field column 1808 may correspond to the second TPMI field 1740. Figure 18 and Figure 19 In the example of FIG, the "TPMI 1" indication included in the first TPMI field column 1806 and / or the second TPMI field column 1808 corresponds to the precoding matrix indication for the first SRS resource set. Additionally, the "TPMI 2" indication included in the first TPMI field column 1806 and / or the second TPMI field column 1808 corresponds to the precoding matrix indication for the second SRS resource set.

[0188] exist Figure 18 and Figure 19 In the example, Figure 16 Compared to the precoding matrix types supported by Table 1600, including a second SRI column 1804 for determining the precoding matrix type allows support for additional precoding matrix types. Similar to example Table 1600, when the value of the type indicator column 1802 is set to "0" or "1", then the value of the second TPMI field column 1808 may be ignored for determining the 8Tx precoding matrix. Additionally, the value of the second SRI column 1804 may also be ignored for determining the 8Tx precoding matrix. However, when the value of the type indicator column 1802 is set to "2" or "3", then the value of the second SRI column 1804 is also used to determine the 8Tx precoding matrix. Figure 18 and Figure 19 In the example, compared to Figure 16 The 8Tx precoding matrix types supported by Table 1600 include a second SRI column 1804 that allows support for eight additional 8Tx precoding matrix types. Figure 14 Examples of all precoding matrix types in Table 20.

[0189] Figure 20 2000 between a network node 2002 and a UE 2004 as presented herein. Aspects of the communication flow 2000 may be similar to Figure 5 Communication flow 500, Figure 15 Communication flow 1500 and / or Figure 17 Communication flow 1700.

[0190] Similar to Figure 15 and Figure 17 In the example of , the network node 2002 outputs an RRC configuration 2010, which is received by the UE 2004. Figure 20 In the example of FIG, RRC configuration 2010 includes a first SRS resource set 2012, a first SRS resource set port indicator 2014, a second SRS resource set 2016, a second SRS resource set port indicator 2018, and an 8-port uplink MIMO indicator 2020. The first SRS resource set 2012 and the second SRS resource set 2016 may indicate two SRS resource sets allocated to UE 2004. Each SRS resource set may be associated with four ports. The first SRS resource set port indicator 2014 may indicate the four ports associated with the first SRS resource set, and the second SRS resource set port indicator 2018 may indicate the four ports associated with the second SRS resource set. The 8-port uplink MIMO indicator 2020 may configure UE 2004 to use the indicated SRS resource set for 8Tx uplink transmission.

[0191] The UE 2004 may use the information provided by the RRC configuration 2010 to determine which two SRS resource sets are associated with 8-port UL MIMO (eg, based on the first SRS resource set 2012 and the second SRS resource set 2016).

[0192] The network node 2002 may output control signaling 2030, which is received by the UE 2004. The network node 2002 may receive an SRS (e.g., in conjunction with a signaling ... Figure 5 The control signaling 2030 is then outputted as described in the example SRS 520. Aspects of the control signaling 2030 may be similar to Figure 4 The network node 2002 may provide control signaling 2030 such as DCI. Figure 15 and Figure 17 In the example of FIG. 2 , the control signaling 2030 includes an SRS resource set indicator 2032 , a first SRI field 2034 , a second SRI field 2036 , a first TPMI field 2038 , and a second TPMI field 2040 .

[0193] exist Figure 20In the example of , UE 2004 can use the information provided by RRC configuration 2010 and control signaling 2030 to determine the 8Tx precoding matrix to be used for uplink transmission 2060. Figure 17 For example, the communication flow 2000 supports all 8Tx pre-coding matrix types. Figure 15 and Figure 17 Compared to the example of Example 26, Example 26 includes independently determining the rank and TPMI associated with the corresponding SRS resource set. That is, the UE 2004 can use the first TPMI field 2038 of the control signaling 2030 to determine the rank and the first TPMI ("TPMI 1"). The UE 2004 can also use the second TPMI field 2040 of the control signaling 2030 to determine the rank and the second TPMI ("TPMI 2").

[0194] For example, at 2050, the UE 2004 may use the SRS resource set indicator 2032 to determine the precoding matrix type (e.g., type 1, type 2, etc.). At 2052, the UE 2004 may use two SRI fields (e.g., a first SRI field 2034 and a second SRI field 2036) of the control signaling 2030 to determine corresponding SRS resources within the two SRS resource sets indicated by the RRC configuration 2010 (e.g., via the first SRS resource set 2012 and the second SRS resource set 2016). At 2054, the UE 2004 may use the first TPMI field 2038 of the control signaling 2030 to determine the rank and the first TPMI ("TPMI 1"), as combined with Figure 8 At 2056, the UE 2004 may determine the rank and the second TPMI ("TPMI2") using the second TPMI field 2040 of the control signaling 2030. The UE 2004 may determine the rank and the first TPMI similarly to determining the rank and the first TPMI (e.g., as combined with Figure 8 Based on the information provided by RRC configuration 2010 and control signaling 2030, UE 2004 can determine the 8Tx precoding matrix. Figure 20 As shown, UE 2004 may send an uplink transmission 2060, which is received by network node 2002. Figure 20In the example of FIG, the SRS resource set indicator 2032, the first TPMI field 2038, and the second TPMI field 2040 jointly specify the 8Tx precoding matrix for uplink transmission 2060. However, the TPMI field is used to independently indicate the first TPMI ("TPMI 1") and the second TPMI ("TPMI 2"). Additionally, in the case where the second TPMI field 2040 independently indicates the rank of the second TPMI, the size of the second TPMI field 2040 can be 6 bits, similar to the size of the first TPMI field 2038, which is different from the example in which the size of the second TPMI field is 5 bits. Figure 15 and Figure 17 In contrast to the second TPMI field of the example of .

[0195] exist Figure 20 In the example of , the precoding matrix type is determined based on the SRS resource set indicator 2032, such as in combination with Figure 15 In other examples, the precoding matrix type can be determined based on the SRS resource set indicator 2032 and the second SRI field 2036, such as in combination with Figure 17 1700. However, as Figure 21 and Figure 22 As shown in the example, it can support Figure 14 Table 1400 shows all the different pre-coding matrix types.

[0196] Figure 21 Depicted is a table 2100 that facilitates mapping of type indicator and TPMI fields to an 8Tx precoding matrix as presented herein. Figure 22 Depicted is a table 2200 that facilitates mapping of type indicator and TPMI fields to an 8Tx precoding matrix as presented herein. Figure 21 and Figure 22 The tables can be read together and illustrate the support Figure 14 All possible precoding matrix types are indicated in the example table 1400 of FIG.

[0197] Example tables 2100 and 2200 include a type indicator column 2102, a first TPMI field column 2104, a second TPMI field column 2106, and an 8Tx precoding matrix column 2108. The value of the type indicator column 2102 may correspond to Figure 20 The SRS resource set indicator 2032 of the first TPMI field column 2104 may correspond to the first TPMI field 2038, and the value of the second TPMI field column 2106 may correspond to the second TPMI field 2040. Figure 21 and Figure 22In the example of FIG, the "TPMI 1" indication included in the first TPMI field column 2104 and / or the second TPMI field column 2106 corresponds to the precoding matrix indication for the first SRS resource set. Additionally, the "TPMI 2" indication included in the first TPMI field column 2104 and / or the second TPMI field column 2106 corresponds to the precoding matrix indication for the second SRS resource set.

[0198] As described above, the first TPMI field 2038 and the second TPMI field 2040 may independently indicate the rank. Figure 21 and Figure 22 In the example of , the combination of the values ​​of the type indicator column 2102, the first TPMI field column 2104, and the second TPMI field column 2106 may indicate the precoding matrix type. Figure 21 and Figure 22 In the example of , when the type indicator is "0", the second TPMI field is reserved, and the TPMI indicated by the first TPMI field is used for the 8Tx precoding matrix. When the type indicator is "1", the first TPMI field is reserved, and the TPMI indicated by the second TPMI field is used for the 8Tx precoding matrix.

[0199] For example, in the first row 2110, the type indicator is "0," the first TPMI field is rank 1 ("1 layer"), and the second TPMI field is reserved. In this combination, the 8Tx precoding matrix is ​​rank-1, type 1. In the second row 2112, the type indicator is "1," the first TPMI field is reserved, and the second TPMI field is rank 1 ("1 layer"). In this combination, the 8Tx precoding matrix is ​​rank-1 type 2.

[0200] In the example where the type indicator is "2", the TPMI indicated by the first TPMI field and the TPMI field is used for the 8Tx precoding matrix. For example, in the third row 2114, the type indicator is "2", the first TPMI field is rank 2 ("2 layers"), and the second TPMI field is rank 2 ("2 layers"). Based on the use of the rank 2 precoding matrix in the first and second layers of the 8Tx precoding matrix, the UE can determine that the 8Tx precoding matrix is ​​rank-4 type 3, as indicated by the rank 4 precoding matrix 1408 of Table 20. For another example, in Figure 22In row 2210 of , the type indicator is "2", the first TPMI field is rank 3 ("3 layers"), and the second TPMI field is rank 4 ("4 layers"). Based on using a rank 3 precoding matrix in the first layer of the 8Tx precoding matrix and a rank 4 precoding matrix in the second layer, the UE may determine that the 8Tx precoding matrix is ​​rank-7 type 2, as indicated by the rank 7 precoding matrix 1414 of Table 20, where the first layer uses a 4Tx rank-3 precoding matrix and the second layer uses a 4Tx rank-4 precoding matrix.

[0201] exist Figure 15 、 Figure 17 and Figure 20 In an example, the network node outputs an RRC configuration including two SRS resource sets, corresponding SRS resource set ports, and an 8-port UL MIMO indicator. In some examples, the network node can be configured to output one SRS resource set in which the SRS resources are 8-port resources. In such an example, the network node can be configured to indicate which ports will use the first precoding matrix and which ports will use the second precoding matrix.

[0202] Figure 23 Illustrated is a communication flow 2300 between a network node 2302 and a UE 2304 as presented herein. Aspects of the communication flow 2300 facilitate precoding matrix indication when providing 8-port SRS resources.

[0203] exist Figure 23 In the example of , the network node 2302 outputs an RRC configuration 2310, which is received by the UE 2304. The RRC configuration 2310 includes an SRS resource set 2312, an 8-port SRS resource indicator 2314, a first port group configuration 2316, and a second port group configuration 2318. The port group (PG) configuration indicates which ports are associated with the precoding matrix. For example, the first port group configuration 2316 may indicate a first subset of ports associated with the first precoding matrix, and the second port group configuration 2318 may indicate a second subset of ports associated with the second precoding matrix. Figure 23 In the example of FIG, the first port group configuration 2316 indicates that ports 0, 1, 4, and 5 are associated with the first pre-coding matrix, and the second port group configuration 2318 indicates that ports 2, 3, 6, and 7 are associated with the second pre-coding matrix. However, other examples may include alternative combinations of ports and port groups. For example, the first port group may include ports 0, 1, 2, and 3, and the second port group may include ports 4, 5, 6, and 7. The ports in the respective port groups may correspond to Figure 4For example, port configuration 2320 may indicate the placement of antenna elements in UE 2304. In this example, it may be understood that port 0 corresponds to first antenna element 402a, port 1 corresponds to third antenna element 402c, ..., port 6 corresponds to sixth antenna element 402f, and port 7 corresponds to eighth antenna element 402h.

[0204] After the network node 2302 configures the UE 2304 via the RRC configuration 2310, the network node 2302 may output control signaling 2330, which is received by the UE 2304. The control signaling 2330 may allow the UE 2304 to determine the 8Tx precoding matrix to apply when sending uplink transmissions to the network node 2302. Aspects of the control signaling 2330 may be similar to Figure 15 、 Figure 17 and / or Figure 20 , and therefore, UE 2304 can determine the 8Tx precoding matrix in a similar manner.

[0205] exist Figure 23 In the example of FIG, the control signaling 2330 includes a precoding matrix type indicator 2332, an SRI field 2334, a first TPMI field 2338, and a second TPMI field 2340. The precoding matrix type indicator 2332 may have a size of 2 bits and is similar to Figure 15 、 Figure 17 and / or Figure 20 The SRS resource set indicator of the SRS resource set. The SRI field 2334 can indicate the SRS resource, such as Figure 15 and Figure 20 In the example described above, UE 2304 adopts the combination of Figure 17 In an example where the described techniques are used to determine the precoding matrix type (e.g., via the SRS resource set indicator and the second SRI field), the control signaling 2330 may include an indicator bit 2336, which may be used along with the precoding matrix type indicator 2332 to determine the precoding matrix type. At 2350, the UE 2304 may determine the 8Tx precoding matrix. The UE 2304 may then transmit an uplink transmission 2360 using the 8Tx precoding matrix.

[0206] The first TPMI field 2338 and the second TPMI field 2340 may be used to determine the first 4Tx pre-coding matrix and the second 4Tx pre-coding matrix, respectively. Figure 15 、 Figure 17 and Figure 20 Therefore, in Figure 23In the example of FIG. 23, UE 2304 may use the precoding matrix type indicator 2332, the first TPMI field 2338, and the second TPMI field 2340 to jointly determine the 8Tx precoding matrix. Figure 15 and Figure 20 In other examples, the UE 2304 may use the precoding matrix type indicator 2332, the indicator bit 2336, the first TPMI field 2338, and the second TPMI field 2340 to determine the 8Tx precoding matrix, as shown in combination with Figure 17 as described in the examples.

[0207] In an example where an 8-port SRS is used (e.g., Figure 23 In the example communication flow 2300 of , the pre-decoding matrix type can be redefined. Figure 24 Depicted is a table 2400 including precoding matrix types for rank 1 through rank 4 as presented herein. Figure 25 A table 2500 including precoding matrix types for rank 5 through rank 8 is depicted. Figure 24 and Figure 25 The pre-coding matrix type is similar in all respects to Figure 14 However, Figure 24 and Figure 25 The pre-decoding matrix types include permutation matrix (P G ). The permutation matrix represents the port group configuration. The permutation matrix can be defined by Equation 1 (below).

[0208] Equation 1: P G =[e 1,1 ,e 1,2 ,e 1,3 ,e 1,4 ,e 2,1 ,e 2,2 ,e 2,3 ,e 2,4 ]

[0209] In Equation 1, the term (e i,j ) is a unit vector with a single non-zero (unit) element representing the jth port in PG i. For example, and with respect to a configuration in which the first port group configuration 2316 includes ports 0, 1, 4, and 5 and the second port group configuration 2318 includes ports 2, 3, 6, and 7 Figure 23 For example, the permutation matrix may be represented by a permutation matrix 2420. The permutation matrix 2420 defines how the ports (eg, antenna elements) of the UE 2304 apply the 8Tx precoding matrix.

[0210] As described above, various aspects disclosed herein facilitate reusing a 4Tx codebook for 8Tx MIMO transmissions. For example, a 4Tx non-coherent codebook may be mapped to an 8Tx non-coherent codebook, a 4Tx partially coherent codebook may be mapped to an 8Tx PC-2 codebook, and a 4Tx fully coherent codebook may be mapped to an 8Tx PC-4 codebook. However, supporting an 8Tx fully coherent codebook may be beneficial. Figure 26 An example of an 8Tx fully coherent (FC) codebook structure is illustrated in FIG.

[0211] exist Figure 26 In the example of FIG26 , an 8Tx FC rank-1 codebook may include 32 precoders and be defined by a rank-1 structure 2602. An 8Tx FC rank-2 codebook may include 16 precoders and may be defined by a rank-2 structure 2604. An 8Tx FC rank-3 codebook may include 8 precoders and may be defined by a rank-3 structure 2606. An 8Tx FC rank-4 codebook may include 8 precoders and may be defined by a rank-4 structure 2608. An 8Tx FC rank-5 codebook may include 8 precoders and may be defined by a rank-5 structure 2610. An 8Tx FC rank-6 codebook may include 8 precoders and may be defined by a rank-6 structure 2612. An 8Tx FC rank-7 codebook may include 4 precoders (or 8 precoders) and may be defined by a rank-7 structure 2614. The 8Tx FC rank-8 codebook may include 4 precoders (or 8 precoders) and may be defined by the rank-8 structure 2616. Figure 26 In the example structure of can be defined by equation 2620, and the term It can be defined by Equation 2622.

[0212] Understandably, Figure 26 The example structure of is illustrative, and other examples may include additional or alternative structures for defining the 8Tx FC codebook.

[0213] In an example where a precoding matrix from the 8Tx FC codebook is used, the network node may output an FC codebook indicator to the UE to signal the UE to use the 8Tx FC codebook to determine the precoding matrix.

[0214] In such examples, the network node may signal that the 8Tx fully coherent codebook is being used by including a fully coherent (FC) codebook indicator along with control signaling to the UE. In some examples, the network node may include the FC codebook indicator along with control signaling to the UE. For example, in Figure 15 、 Figure 17 and Figure 20In an example, the network node may output an FC codebook indicator (e.g., FC codebook indicator 1570, FC codebook indicator 1770, or FC codebook indicator 2070), which may indicate to the UE whether to use the FC codebook to determine the 8Tx precoding matrix or to use the NC / PC-2 / PC-4 codebook to determine the 8Tx precoding matrix. For example, the FC codebook indicator may be a 1-bit indicator that indicates when the UE is to use the FC codebook. For example, when the FC codebook indicator is set to a first value (e.g., "0"), the UE may determine to use the NC / PC-2 / PC-4 codebook, as previously described in conjunction with Figure 15 、 Figure 17 and Figure 20 Additionally, when the FC codebook indicator is set to a second value (e.g., "1"), the UE may determine to use the FC codebook. In the example where the FC codebook indicator indicates to use the FC codebook, the UE may determine the 8Tx FC precoding matrix using the first TPMI field and the second TPMI field.

[0215] Despite Figure 15 、 Figure 17 and Figure 20 The example FC codebook indicator is illustrated in the example of FIG as a separate communication from the control signaling from the network node to the UE, but in other examples, the FC codebook indicator may be included with the control signaling.

[0216] In some examples, the FC codebook indicator may be based on a Figure 15 For example, and similar to Figure 17 For example, UE 1504 may determine SRS resources using first SRI field 1534. For example, when first SRI field 1534 is set to "0," SRS resource 0 in the first SRS resource set as indicated by first SRS resource set 1512 and SRS resource 0 in the second SRS resource set as indicated by second SRS resource set 1516 are indicated SRS resources. Additionally, when first SRI field 1534 is set to "1," SRS resource 1 in the first SRS resource set as indicated by first SRS resource set 1512 and SRS resource 1 in the second SRS resource set and second SRS resource set 1516 are indicated SRS resources.

[0217] The UE 1504 may use the second SRI field 1536 to determine whether to use the FC codebook or the NC / PC-2 / PC-4 codebook. For example, when the second SRI field 1536 is set to a first value (e.g., "0"), the UE 1504 may determine to use the NC / PC-2 / PC-4 codebook, as previously described in conjunction with Figure 15In such an example, the UE 1504 may use the two TPMI fields and the SRS resource set indicator 1532 to determine the 8Tx precoding matrix.

[0218] Additionally, when the second SRI field 1536 is set to a second value (eg, "1"), the UE 1504 may determine to use the FC codebook. In such an example, the UE 1504 may use two TPMI fields to determine the 8Tx FC precoding matrix.

[0219] In another example, the UE may use Figure 20 For example, when the SRS resource set indicator 2032 is set to "0", "1" or "2", the UE 2004 may determine to use the NC / PC-2 / PC-4 codebook, as previously described in conjunction with Figure 20 In such an example, the UE 2004 may use the two TPMI fields, the SRI field, and the SRS resource set indicator 2032 to determine the 8Tx precoding matrix.

[0220] Additionally, when the SRS resource set indicator 2032 is set to "3," the UE 2004 may determine to use the FC codebook. In such an example, the UE 2004 may use two TPMI fields to determine the 8Tx FC precoding matrix.

[0221] Figure 27 Depicted is a table 2700 that facilitates mapping of type indicator and TPMI fields to an 8Tx precoding matrix as presented herein. Figure 28 Depicted is a table 2800 that facilitates mapping type indicator and TPMI fields to an 8Tx precoding matrix as presented herein. Figure 27 and Figure 28 The tables can be read together and illustrate the support Figure 14 All possible precoding matrix types are indicated in the example table 1400, as well as the 8Tx FC precoding matrix. Figure 27 and Figure 28 An example table similar to Figure 21 and Figure 22 The tables are the same except that they include an additional row for type indicator “3.” In the example where the type indicator is “3,” the UE 2004 may use two TPMI fields to determine the 8Tx FC precoding matrix.

[0222] exist Figure 15 、 Figure 17 and Figure 20 In the example, the network node output is the same as Figure 5The example control signaling 540 is similar to the control signaling of FIG. However, other examples may use different signaling to indicate the 8Tx precoding matrix.

[0223] Figure 29 2900 between a network node 2902 and a UE 2904 as presented herein. Aspects of the communication flow 2900 may be similar to Figure 23 For example, the network node 2902 may output an RRC configuration 2910, which may be received by the UE 2904. The RRC configuration 2910 may configure the UE 2904 for 8Tx UL MIMO. Figure 29 In the example of , RRC configuration 2910 includes SRS resource set 2912, 8-port SRS resource indicator 2914, first port group configuration 2916 and second port group configuration 2918. The PG configuration indicates which ports are associated with the precoding matrix. Figure 29 As shown, first port group configuration 2916 indicates that ports 0, 1, 4, and 5 are associated with the first precoding matrix, and second port group configuration 2918 indicates that ports 2, 3, 6, and 7 are associated with the second precoding matrix. However, other examples may include alternative combinations of ports and port groups.

[0224] The network node 2902 outputs an uplink precoding matrix indication 2930, which is received by the UE 2904. The network node 2902 may output the uplink precoding matrix indication 2930 via DCI. The uplink precoding matrix indication 2930 may indicate the precoding matrix type and the TPMI. Figure 24 and Figure 25 The example table is described.

[0225] UE 2904 may use information from RRC configuration 2910 and uplink precoding matrix indication 2930 to determine the 8Tx precoding matrix 2950. Figure 29 As shown, UE 2904 may transmit an uplink transmission 2960 obtained by network node 2902. UE 2904 may transmit uplink transmission 2960 using 8Tx precoding matrix 2950.

[0226] As described above, the 8Tx precoding matrix 2950 may be associated with a rank (e.g., rank-1, rank-2, ..., rank-8). Additionally, the 8Tx precoding matrix 2950 may be associated with a type (e.g., type 1, type 2, etc.). The uplink precoding matrix indication 2930 may indicate the precoding matrix type and TPMI of the 4Tx precoding matrix to be used in the 8Tx precoding matrix.

[0227] For rank-1 8Tx codebook, the precoding matrix can be associated with type 1 or type 2. Additionally, there are 28 TPMI indices associated with the NC precoding matrix associated with rank-1, PC-2 precoding matrix, and PC-4 matrix, as shown in the example of Figure 9 As described in Table 900.

[0228] Figures 30 to 47 An example table illustrating uplink precoding matrix indication 2930 for ranks 1 to 8 is depicted. Figure 30 In the example of FIG, the first table 3000 illustrates an uplink precoding matrix indication 2930 for rank 1. As shown in the first table 3000, for a rank-1 NC precoding matrix, the uplink precoding matrix indication 3002 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3002 may also include a 2-bit TPMI field to indicate one of four states associated with 4Tx rank-1 TPMI indices 0 to 3.

[0229] For a rank-1 PC-2 precoding matrix, the uplink precoding matrix indication 3004 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3004 may also include a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-1 TPMI indices 4 to 11.

[0230] For a rank-1 PC-4 precoding matrix, the uplink precoding matrix indication 3006 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3006 may also include a 2-bit TPMI field to indicate one of 16 states associated with 4Tx rank-1 TPMI indices 12 to 27.

[0231] For a rank-2 8Tx codebook, the precoding matrix may be associated with type 1, type 2, or type 3, as shown in Table 2400 . Figure 30 The second table 3010 illustrates a first aspect for illustrating an uplink precoding matrix indication 2930 for rank 2. In the second table 3010, the uplink precoding matrix indication 2930 can be configured to indicate only a type 1 precoding matrix or a type 2 precoding matrix. For example, for a rank-2 NC precoding matrix, the uplink precoding matrix indication 3012 can include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3012 can also include a 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indices 0 to 5.

[0232] For a rank-2 PC-2 precoding matrix, the uplink precoding matrix indication 3014 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3014 may also include a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13.

[0233] For a rank-2 PC-4 precoding matrix, the uplink precoding matrix indication 3016 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3016 may also include a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21.

[0234] In another aspect, the uplink precoding matrix indication 2930 may be configured to indicate only the rank-2 type-3 precoding matrix. In such an example, the uplink precoding matrix indication 2930 may skip including the PG indication (e.g., the PG indication may be reserved or disabled). The uplink precoding matrix indication 2930 may also include two TPMI fields to indicate a first precoding matrix and a second precoding matrix associated with the rank-2 type-3 precoding matrix.

[0235] exist Figure 30 In the third table 3020 of , the uplink precoding matrix indication 2930 may be configured to indicate only a type 3 precoding matrix. For example, for a rank-2 NC precoding matrix, the uplink precoding matrix indication 3022 may include two 2-bit TPMI fields to indicate one of four states associated with 4Tx rank-1 TPMI indices 0 to 3.

[0236] For a rank-2 PC-2 precoding matrix, the uplink precoding matrix indication 3024 may include two 3-bit TPMI fields to indicate one of eight states associated with 4Tx rank-1 TPMI indices 4 to 11.

[0237] For a rank-2 PC-4 precoding matrix, the uplink precoding matrix indication 3026 may include two 4-bit TPMI fields to indicate one of 16 states associated with 4Tx rank-1 TPMI indices 12 to 27.

[0238] In some examples, the same pre-decoder restrictions may apply to both PG configurations. For example, the first pre-decoding matrix and the second pre-decoding matrix may be configured to be the same (e.g., W 4Tx,r＝1 =W′ 4Tx,r＝1 In such examples, the uplink precoding matrix indication 2930 associated with the third table 3020 may include a TPMI field.

[0239] In another aspect related to the rank-2 precoding matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the Type 1, Type 2, or Type 3 precoding matrices without limitation. In such an example, the uplink precoding matrix indication 2930 may include a 2-bit PG indication to indicate Type 1, Type 2, or Type 3. For example, code point "00" may indicate Type 1, code point "01" may indicate Type 2, code point "10" may indicate Type 3, and code point "11" may be reserved. In another example, code point "00" may be reserved, code point "10" may indicate Type 1, code point "01" may indicate Type 2, and code point "11" may indicate Type 3. However, other examples may utilize alternative mappings between code points and precoding matrix types.

[0240] In addition to the 2-bit PG indication, the uplink precoding matrix indication 2930 may include two TPMI fields to indicate the first 4Tx precoding matrix and the second 4Tx precoding matrix.

[0241] exist Figure 31 In the example of , the first table 3100 depicts indicating any of type 1, type 2, or type 3 precoding matrices without limitation. For example, for a rank-2 NC precoding matrix indicating type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3102 may include: a 2-bit PG indication; and a 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indices 0 to 5. In such an example, the second TPMI field may be reserved. For a rank-2 NC precoding matrix indicating type 3 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3104 may include: a 2-bit PG indication; and two 2-bit TPMI fields to indicate one of four states associated with 4Tx rank-1 TPMI indices 0 to 3.

[0242] For a rank-2 PC-2 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3106 may include: a 2-bit PG indication; and a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13. In such an example, the second TPMI field may be reserved. For a rank-2 PC-2 precoding matrix indicating type 3 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3108 may include: a 2-bit PG indication; and two 3-bit TPMI fields to indicate one of eight states associated with 4Tx rank-1 TPMI indices 4 to 11.

[0243] For a rank-2 PC-4 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3110 may include: a 2-bit PG indication; and a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21. In such an example, the second TPMI field may be reserved. For a rank-2 PC-4 precoding matrix indicating type 3 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3112 may include: a 2-bit PG indication; and two 4-bit TPMI fields to indicate one of 16 states associated with 4Tx rank-1 TPMI indices 12 to 27.

[0244] In another aspect related to the rank-2 precoding matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the type 1, type 2, or type 3 precoding matrices, with restrictions. In such an example, the uplink precoding matrix indication 2930 can include a 2-bit PG indication to indicate type 1, type 2, or type 3, as described in conjunction with the PG indication of the first table 3100.

[0245] Additionally, the uplink precoding matrix indication 2930 may include the same precoder restriction, such that the first precoding matrix and the second precoding matrix may be configured to be the same (eg, W 4Tx,r＝1 =W′ 4Tx,r＝1 ). In such examples, in the case of Type 1, Type 2 or Type 3, Figure 31 The uplink precoding matrix indication 2930 associated with the second table 3120 may include a TPMI field.

[0246] exist Figure 31 In the example of , the second table 3120 depicts indicating any of the type 1, type 2, or type 3 precoding matrices with restrictions. For example, for indicating a rank-2 NC precoding matrix of type 1 or type 2 (e.g., based on a PG indication code point), the uplink precoding matrix indication 3122 may include: a 2-bit PG indication; and a 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indices 0 to 5. For indicating a rank-2 NC precoding matrix of type 3 (e.g., based on a PG indication code point), the uplink precoding matrix indication 3124 may include: a 2-bit PG indication; and a 2-bit TPMI field to indicate one of four states associated with 4Tx rank-1 TPMI indices 0 to 3.

[0247] For a rank-2 PC-2 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3126 may include a 2-bit PG indication and a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13. For a rank-2 PC-2 precoding matrix indicating type 3 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3128 may include a 2-bit PG indication and a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-1 TPMI indices 4 to 11.

[0248] For indicating a rank-2 PC-4 precoding matrix of type 1 or type 2 (e.g., based on a PG indication code point), the uplink precoding matrix indication 3130 may include a 2-bit PG indication and a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21. For indicating a rank-2 PC-4 precoding matrix of type 3 (e.g., based on a PG indication code point), the uplink precoding matrix indication 3132 may include a 2-bit PG indication and a 4-bit TPMI field to indicate one of 16 states associated with 4Tx rank-1 TPMI indices 12 to 27.

[0249] For the rank-3 8Tx codebook, the precoding matrix may be associated with type 1, type 2, type 3, or type 4, as shown in Table 2400 . Figure 32 The first table 3200 illustrates a first aspect of an uplink precoding matrix indication 2930 for rank 3. In the first table 3200, the uplink precoding matrix indication 2930 can be configured to indicate only a type 1 precoding matrix or a type 2 precoding matrix. For example, for a rank-3 NC precoding matrix, the uplink precoding matrix indication 3202 can include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3202 can also include a 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0.

[0250] For a rank-3 PC-2 precoding matrix, the uplink precoding matrix indication 3204 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3204 may also include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indexes 1 to 2.

[0251] For a rank-3 PC-4 precoding matrix, the uplink precoding matrix indication 3206 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3206 may also include a 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6.

[0252] In another aspect, the uplink precoding matrix indication 2930 may be configured to indicate only a rank-3 type-3 precoding matrix. In such an example, the uplink precoding matrix indication 2930 may skip including a PG indication (e.g., the PG indication may be reserved or disabled). The uplink precoding matrix indication 2930 may also include two TPMI fields to indicate a first precoding matrix and a second precoding matrix associated with the rank-3 type-3 precoding matrix.

[0253] exist Figure 32 In the second table 3210 of , the uplink precoding matrix indication 2930 may be configured to indicate only a type 3 precoding matrix. For example, for a rank-3 NC precoding matrix, the uplink precoding matrix indication 3212 may include a 3-bit first TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indices 0 to 5. The uplink precoding matrix indication 3212 may also include a 2-bit second TPMI field to indicate one of four states associated with 4Tx rank-1 TPMI indices 0 to 3.

[0254] For a rank-3 PC-2 precoding matrix, the uplink precoding matrix indication 3214 may include a 3-bit first TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13. The uplink precoding matrix indication 3214 may also include a 3-bit second TPMI field to indicate one of eight states associated with 4Tx rank-1 TPMI indices 4 to 11.

[0255] For a rank-3 PC-4 precoding matrix, the uplink precoding matrix indication 3216 may include a 3-bit first TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21. The uplink precoding matrix indication 3216 may also include a 4-bit second TPMI field to indicate one of sixteen states associated with 4Tx rank-1 TPMI indices 12 to 27.

[0256] In some examples, when the following restrictions apply, Figure 32 The second table 3210 uses a single TPMI field:

[0257] W 4Tx,r＝1=[W 4Tx,r＝2 ]1

[0258] In the above restrictions, the item “[] x ” means using the first x columns of the matrix [ ]. Therefore, in the above restrictions, the precoding matrix (W 4Tx,r＝2 ) is used for the second pre-decoding matrix.

[0259] In another aspect related to indicating a rank-3 matrix, the uplink precoding matrix indication 2930 may be configured to indicate only a rank-3 type 4 precoding matrix. In such an example, the descriptions related to the first TPMI field and the second TPMI field of the second table 3210 may be swapped, such as Figure 32 As depicted in the third table 3220.

[0260] In another aspect related to indicating a rank-3 matrix, the uplink precoding matrix indication 2930 may be configured to indicate any of the type 1 to 3 precoding matrices without limitation. For example, the uplink precoding matrix indication 2930 may include a 2-bit PG indication to indicate type 1, type 2, or type 3, as in combination with Figure 31 The PG indication of the first table 3100 is as described above.

[0261] In addition to the 2-bit PG indication, the uplink precoding matrix indication 2930 may include two TPMI fields to indicate the first 4Tx precoding matrix and the second 4Tx precoding matrix.

[0262] exist Figure 33 In the example of , Table 3300 depicts indicating any of type 1, type 2, or type 3 precoding matrices without limitation. For example, for indicating a type 1 or type 2 rank-3 NC precoding matrix (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3302 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0. In such an example, the second TPMI field may be reserved. For indicating a type 3 rank-3 NC precoding matrix (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3304 may include: a 2-bit PG indication; a first 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indices 0 to 5; and a second 2-bit TPMI field to indicate one of four states associated with 4Tx rank-1 TPMI indices 0 to 3.

[0263] For a rank-3 PC-2 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3306 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2. In such an example, the second TPMI field may be reserved. For a rank-3 PC-2 precoding matrix indicating type 3 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3308 may include: a 2-bit PG indication; a first 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-1 TPMI indices 4 to 11.

[0264] For a rank-3 PC-4 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3310 may include: a 2-bit PG indication; and a 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6. In such an example, the second TPMI field may be reserved. For a rank-3 PC-4 precoding matrix indicating type 3 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3312 may include: a 2-bit PG indication; a first 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21; and a second 4-bit TPMI field to indicate one of 16 states associated with 4Tx rank-1 TPMI indices 12 to 27.

[0265] In another aspect related to indicating a rank-4 matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the precoding matrices of type 1 to 3 without limitation. For example, the uplink precoding matrix indication 2930 can include a 2-bit PG indicator to indicate type 1, type 2, type 3, or type 4 based on the code point.

[0266] In addition to the 2-bit PG indication, the uplink precoding matrix indication 2930 may include two TPMI fields to indicate the first 4Tx precoding matrix and the second 4Tx precoding matrix. In such an example, the indication of the type 1, type 2, or type 3 precoding matrix may be the same as Figure 33 The same as indicated in Table 3300.

[0267] To indicate the type-4 precoding matrix, descriptions associated with the first TPMI field and the second TPMI field of table 3300 associated with the type-3 precoding matrix may be swapped.

[0268] For example, for a rank-3NC precoding matrix indicating type 4 (e.g., based on a PG indication code point), the uplink precoding matrix indication 3314 may include: a 2-bit PG indication; a first 2-bit TPMI field to indicate one of four states associated with 4Tx rank-1 TPMI indices 0 to 3; and a second 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indices 0 to 5.

[0269] For a rank-3 PC-2 precoding matrix indicating type 4 (e.g., based on a PG indication code point), the uplink precoding matrix indication 3316 may include: a 2-bit PG indication; a first 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-1 TPMI indices 4 to 11; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13.

[0270] For a rank-3 PC-4 precoding matrix indicating type 4 (e.g., based on a PG indication code point), the uplink precoding matrix indication 3318 may include: a 2-bit PG indication; a first 4-bit TPMI field to indicate one of 16 states associated with 4Tx rank-1 TPMI indices 12 to 27; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21.

[0271] In another aspect related to the rank-3 precoding matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the type 1 to 3 precoding matrices or any of the type 1 to 4 precoding matrices, with restrictions. In such an example, the uplink precoding matrix indication 2930 can include a 2-bit PG indication to indicate the precoding matrix type via a code point.

[0272] Additionally, the uplink precoding matrix indication 2930 may include a single TPMI field having a combination of Figure 32 The same restrictions as described in the second table 3210 (reproduced below):

[0273] W 4Tx,r＝1 =[W 4Tx,r＝2 ]1

[0274] The same pre-decoder restriction allows the first pre-decoding matrix and the second pre-decoding matrix to be configured to be the same (eg, W 4Tx,r＝1 =W′ 4Tx,r＝1 ). In such examples, in the case of Type 1 to 3 or Type 1 to 4, Figure 34The uplink precoding matrix indication 2930 associated with the first table 3400 may include a TPMI field.

[0275] exist Figure 34 In the example of FIG, the first table 3400 illustrates indicating any one of precoding matrix types 1 to 3 with restrictions or indicating any one of precoding matrix types 1 to 4 with restrictions. For example, for indicating a rank-3 NC precoding matrix of type 1 or type 2 (e.g., based on a PG indication code point), the uplink precoding matrix indication 3402 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0. For indicating a rank-3 NC precoding matrix of type 3 (or type 4) (e.g., based on a PG indication code point), the uplink precoding matrix indication 3404 may include: a 2-bit PG indication; and a 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indexes 0 to 5.

[0276] For indicating a rank-3 PC-2 precoding matrix of type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3406 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2. For indicating a rank-3 PC-2 precoding matrix of type 3 (or type 4) (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3408 may include: a 2-bit PG indication; and a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13.

[0277] For a rank-3 PC-4 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3410 may include a 2-bit PG indication and a 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6. For a rank-3 PC-4 precoding matrix indicating type 3 (or type 4) (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3412 may include a 2-bit PG indication and a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21.

[0278] For the rank-4 8Tx codebook, the precoding matrix can be associated with type 1, type 2, or type 3, as shown in Table 2400. Figure 34The second table 3420 illustrates a first aspect for illustrating an uplink precoding matrix indication 2930 for rank 4. In the second table 3420, the uplink precoding matrix indication 2930 can be configured to indicate only a type 1 precoding matrix or a type 2 precoding matrix. For example, for a rank-4 NC precoding matrix, the uplink precoding matrix indication 3422 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3422 may also include a 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0279] For a rank-4 PC-2 precoding matrix, the uplink precoding matrix indication 3424 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3424 may also include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2.

[0280] For a rank-4 PC-4 precoding matrix, the uplink precoding matrix indication 3426 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3426 may also include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 3 to 4.

[0281] In another aspect, the uplink precoding matrix indication 2930 may be configured to indicate only the rank-4 type 3 precoding matrix. In such an example, the uplink precoding matrix indication 2930 may skip including the PG indication (e.g., the PG indication may be reserved or disabled). The uplink precoding matrix indication 2930 may also include two TPMI fields to indicate a first precoding matrix and a second precoding matrix associated with the rank-4 type 3 precoding matrix.

[0282] exist Figure 35 In the first table 3500, the uplink precoding matrix indication 2930 may be configured to indicate only a type 3 precoding matrix. For example, for a rank-4 NC precoding matrix, the uplink precoding matrix indication 3502 may include two 3-bit TPMI fields to indicate one of six states associated with 4Tx rank-2 TPMI indices 0 to 5.

[0283] For a rank-4 PC-2 precoding matrix, the uplink precoding matrix indication 3504 may include two 3-bit TPMI fields to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13.

[0284] For a rank-4 PC-4 precoding matrix, the uplink precoding matrix indication 3506 may include two 3-bit TPMI fields to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14-21.

[0285] In some examples, the same pre-decoder restrictions may apply to both PG configurations. For example, the first pre-decoding matrix and the second pre-decoding matrix may be configured to be the same (e.g., W 4Tx,r＝2 =W′ 4Tx,r＝2 In such examples, the uplink precoding matrix indication 2930 associated with the first table 3500 may include a TPMI field.

[0286] In another aspect related to the rank-4 precoding matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the type 1, type 2, or type 3 precoding matrices without limitation. In such an example, the uplink precoding matrix indication 2930 may include a 2-bit PG indication to indicate type 1, type 2, or type 3 based on the code point, such as in combination with Figure 31 As described in the first table 3100.

[0287] In addition to the 2-bit PG indication, the uplink precoding matrix indication 2930 may include two TPMI fields to indicate the first 4Tx precoding matrix and the second 4Tx precoding matrix.

[0288] exist Figure 35 In the example of , the second table 3510 depicts indicating any of type 1, type 2, or type 3 precoding matrices without limitation. For example, for a rank-4 NC precoding matrix indicating type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3512 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0. In such an example, the second TPMI field may be reserved. For a rank-2 NC precoding matrix indicating type 3 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3514 may include: a 2-bit PG indication; and two 3-bit TPMI fields to indicate one of six states associated with 4Tx rank-2 TPMI indices 0 to 5.

[0289] For a rank-4 PC-2 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3516 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2. In such an example, the second TPMI field may be reserved. For a rank-4 PC-2 precoding matrix indicating type 3 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3518 may include: a 2-bit PG indication; and two 3-bit TPMI fields to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13.

[0290] For a rank-4 PC-4 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3520 may include a 2-bit PG indication and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4. In such an example, the second TPMI field may be reserved. For a rank-4 PC-4 precoding matrix indicating type 3 (e.g., based on a PG indicator codepoint), the uplink precoding matrix indication 3522 may include a 2-bit PG indication and two 3-bit TPMI fields to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21.

[0291] In another aspect related to the rank-4 precoding matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the type 1, type 2, or type 3 precoding matrices, with restrictions. In such an example, the uplink precoding matrix indication 2930 can include a 2-bit PG indication to indicate type 1, type 2, or type 3, as described in conjunction with the PG indication of the first table 3100.

[0292] Additionally, the uplink precoding matrix indication 2930 may include the same precoder restriction, such that the first precoding matrix and the second precoding matrix may be configured to be the same (eg, W 4Tx,r＝2 =W′ 4Tx,r＝2 ). In such examples, in the case of Type 1, Type 2 or Type 3, Figure 36 The uplink precoding matrix indication 2930 associated with the first table 3600 may include a TPMI field.

[0293] exist Figure 36In the example of FIG, the first table 3600 illustrates indicating any of type 1, type 2, or type 3 precoding matrices with restrictions. For example, for indicating a rank-4 NC precoding matrix of type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3602 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0. For indicating a rank-4 NC precoding matrix of type 3 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3604 may include: a 2-bit PG indication; and a 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indices 0 to 5.

[0294] For indicating a rank-4 PC-2 precoding matrix of type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3606 may include a 2-bit PG indication and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2. For indicating a rank-4 PC-2 precoding matrix of type 3 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3608 may include a 2-bit PG indication and a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13.

[0295] For a rank-4 PC-4 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3610 may include a 2-bit PG indication and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4. For a rank-4 PC-4 precoding matrix indicating type 3 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3612 may include a 2-bit PG indication and a 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21.

[0296] For the rank-5 8Tx codebook, the precoding matrix may be associated with type 1, type 2, type 3, or type 4, as shown in Table 2400 . Figure 36 The second table 3620 illustrates a first aspect for illustrating an uplink precoding matrix indication 2930 for rank 5. In the second table 3620, the uplink precoding matrix indication 2930 may be configured to indicate only a type 1 precoding matrix or a type 2 precoding matrix with a restriction similar to that in conjunction with Figure 32For example, the following restrictions may be applied such that only one TPMI field is included in the uplink precoding matrix indication 2930:

[0297] W 4Tx,r＝2 =[W 4Tx,r＝3 ]2

[0298] In the above constraints, the pre-decoding matrix (W 4Tx,r＝3 ) are used for the second precoding matrix. For a rank-5 NC precoding matrix, the uplink precoding matrix indication 3622 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3622 may also include a 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0.

[0299] For a rank-5 PC-2 precoding matrix, the uplink precoding matrix indication 3624 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3624 may also include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indexes 1 to 2.

[0300] For a rank-5 PC-4 precoding matrix, the uplink precoding matrix indication 3626 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3206 may also include a 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6.

[0301] In examples where only Type 1 is allowed, the PG indication may be disabled or reserved.

[0302] In another aspect related to the rank-5 8Tx codebook, the uplink precoding matrix indication 2930 can be configured to indicate only the type 3 precoding matrix or the type 4 precoding matrix with restrictions similar to those in conjunction with Figure 32 For example, the following restrictions may be applied such that only one TPMI field is included in the uplink precoding matrix indication 2930:

[0303] W 4Tx,r＝1 =[W 4Tx,r＝4 ]1

[0304] In the above constraints, the pre-decoding matrix (W 4Tx,r＝4 ) is used for the second pre-decoding matrix, such as Figure 36As shown in the third table 3640 of . For the rank-5 NC precoding matrix, the uplink precoding matrix indication 3642 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 3 or type 4. The uplink precoding matrix indication 3642 may also include a 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0305] For a rank-5 PC-2 precoding matrix, the uplink precoding matrix indication 3644 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 3 or type 4. The uplink precoding matrix indication 3644 may also include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2.

[0306] For a rank-5 PC-4 precoding matrix, the uplink precoding matrix indication 3646 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 3 or type 4. The uplink precoding matrix indication 3646 may also include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4.

[0307] In examples where only Type 3 is allowed, the PG indication may be disabled or reserved.

[0308] In another aspect related to the rank-5 8Tx codebook, the uplink precoding matrix indication 2930 can be configured to indicate only the type 1 precoding matrix or the type 2 precoding matrix with restrictions similar to those in conjunction with Figure 32 For example, the following restrictions may apply so that the second precoding matrix can be derived from the first precoding matrix included in the uplink precoding matrix indication 2930:

[0309] W 4Tx,r＝2 =[W′ 4Tx,r＝3 ]2

[0310] In the above constraints, the pre-coding matrix (W′ 4Tx,r＝3 ) is used for the second precoding matrix. For example, the first TPMI field may indicate the precoding matrix ("W 4Tx,r＝3 ”), and the second TPMI field may indicate a precoding matrix (“W′ 4Tx,r＝3 ”) for Figure 37 The first table is 3700.

[0311] For a rank-5 NC precoding matrix, the uplink precoding matrix indication 3702 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3622 may also include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0.

[0312] For a rank-5 PC-2 precoding matrix, the uplink precoding matrix indication 3704 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3704 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indexes 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indexes 1 to 2.

[0313] For the rank-5 PC-4 precoding matrix, the uplink precoding matrix indication 3706 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3706 may also include: a first 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6; and a second 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6.

[0314] In examples where only Type 1 is allowed, the PG indication may be disabled or reserved.

[0315] In another aspect related to the rank-5 8Tx codebook, the uplink precoding matrix indication 2930 can be configured to indicate only the type 3 precoding matrix or the type 4 precoding matrix with restrictions similar to those in conjunction with Figure 32 For example, the following restrictions may apply so that the second precoding matrix can be derived from the first precoding matrix included in the uplink precoding matrix indication 2930:

[0316] W 4Tx,r＝1 =[W′ 4Tx,r＝4 ]1

[0317] In the above constraints, the pre-decoding matrix (W 4Tx,r＝4 ) is used for the second precoding matrix. For example, the first TPMI field may indicate the precoding matrix ("W 4Tx,r＝4 ”), and the second TPMI field may indicate a precoding matrix (“W′ 4Tx,r＝4”) for Figure 37 The second table 3710.

[0318] For a rank-5 NC precoding matrix, the uplink precoding matrix indication 3712 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 3 or type 4. The uplink precoding matrix indication 3712 may also include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0319] For a rank-5 PC-2 precoding matrix, the uplink precoding matrix indication 3714 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 3 or type 4. The uplink precoding matrix indication 3714 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2.

[0320] For a rank-5 PC-4 precoding matrix, the uplink precoding matrix indication 3716 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 3 or type 4. The uplink precoding matrix indication 3716 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4.

[0321] In examples where only Type 3 is allowed, the PG indication may be disabled or reserved.

[0322] In another aspect related to the rank-5 8Tx codebook, the uplink precoding matrix indication 2930 may be configured to indicate a type 1 precoding matrix or a type 2 precoding matrix using only different TPMIs indicated by the first TPMI field and the second TPMI field of the uplink precoding matrix indication 2930. For example, the first TPMI field may indicate a precoding matrix (“W 4Tx,r＝3 ”), and the second TPMI field may indicate a precoding matrix (“W 4Tx,r＝2 ”) for Figure 37 The third table 3720.

[0323] For the rank-5 NC precoding matrix, the uplink precoding matrix indication 3722 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3722 may also include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0; and a second 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indexes 0 to 5.

[0324] For a rank-5 PC-2 precoding matrix, the uplink precoding matrix indication 3724 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3724 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13.

[0325] For a rank-5 PC-4 precoding matrix, the uplink precoding matrix indication 3726 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 3726 may also include: a first 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-3 TPMI indices 14 to 21.

[0326] In examples where only Type 1 is allowed, the PG indication may be disabled or reserved.

[0327] In another aspect related to the rank-5 8Tx codebook, the uplink precoding matrix indication 2930 may be configured to indicate a type 3 precoding matrix or a type 4 precoding matrix using only different TPMIs indicated by the first TPMI field and the second TPMI field of the uplink precoding matrix indication 2930. For example, the first TPMI field may indicate a precoding matrix (“W 4Tx,r＝4 ”), and the second TPMI field may indicate a precoding matrix (“W 4Tx,r＝1 ”) for Figure 38 The first table is 3800.

[0328] For a rank-5 NC precoding matrix, the uplink precoding matrix indication 3802 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 3 or type 4. The uplink precoding matrix indication 3802 may also include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 2-bit TPMI field to indicate one of four states associated with 4Tx rank-1 TPMI indexes 0 to 3.

[0329] For a rank-5 PC-2 precoding matrix, the uplink precoding matrix indication 3804 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 3 or type 4. The uplink precoding matrix indication 3804 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 4 to 11.

[0330] For a rank-5 PC-4 precoding matrix, the uplink precoding matrix indication 3806 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 3 or type 4. The uplink precoding matrix indication 3806 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4; and a second 4-bit TPMI field to indicate one of 16 states associated with 4Tx rank-1 TPMI indices 12 to 27.

[0331] In examples where only Type 3 is allowed, the PG indication may be disabled or reserved.

[0332] In another aspect related to the rank-5 precoding matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the precoding matrices of types 1 to 4, with restrictions. In such an example, the uplink precoding matrix indication 2930 can include a 2-bit PG indication to indicate the precoding matrix type via a codepoint.

[0333] Additionally, the uplink precoding matrix indication 2930 may include a single TPMI field having a combination of Figure 37 The same restrictions as described in the first table 3700 and the second table 3710.

[0334] exist Figure 38In the example of , the second table 3810 depicts indicating any of precoding matrix types 1 to 4 with restrictions. For example, for indicating a rank-5 NC precoding matrix of type 1 or type 2 (e.g., based on a PG indication code point), the uplink precoding matrix indication 3812 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0. For indicating a rank-5 NC precoding matrix of type 3 or type 4 (e.g., based on a PG indication code point), the uplink precoding matrix indication 3814 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0335] For a rank-5 PC-2 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3816 may include a 2-bit PG indication and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2. For a rank-5 PC-2 precoding matrix indicating type 3 or type 4 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3818 may include a 2-bit PG indication and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2.

[0336] For a rank-5 PC-4 precoding matrix indicating type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3820 may include a 2-bit PG indication and a 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6. For a rank-5 PC-4 precoding matrix indicating type 3 or type 4 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3822 may include a 2-bit PG indication and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4.

[0337] In another aspect related to indicating a rank-5 matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the precoding matrices of type 1 to 4, with restrictions. For example, the uplink precoding matrix indication 2930 can include a 2-bit PG indication to indicate type 1, type 2, type 3, or type 4 based on the PG indication code point.

[0338] In addition to the 2-bit PG indication, the uplink precoding matrix indication 2930 may include two TPMI fields to indicate the first 4Tx precoding matrix and the second 4Tx precoding matrix. In the example where the uplink precoding matrix indication 2930 indicates a type 1 or type 2 precoding matrix, the following restrictions may apply:

[0339] W 4Tx,r＝2 =[W′ 4Tx,r＝3 ]2

[0340] In examples where the uplink precoding matrix indication 2930 indicates a type 3 or type 4 precoding matrix, the following restrictions may apply:

[0341] W 4Tx,r＝1 =[W′ 4Tx,r＝4 ]1.

[0342] exist Figure 39 In the example of , table 3900 depicts indicating any of type 1, type 2, type 3, or type 4 precoding matrices with restrictions. For example, for indicating a type 1 or type 2 rank-5 NC precoding matrix (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3902 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0. For indicating a type 3 or type 4 rank-5 NC precoding matrix (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 3904 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0343] For a rank-5 PC-2 precoding matrix indicating type 1 or type 2, the uplink precoding matrix indication 3906 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2. For a rank-5 PC-2 precoding matrix indicating type 3 or type 4, the uplink precoding matrix indication 3908 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2.

[0344] For a rank-5 PC-4 precoding matrix indicating type 1 or type 2, the uplink precoding matrix indication 3910 may include: a 2-bit PG indication; a first 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6; and a second 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6. For a rank-5 PC-4 precoding matrix indicating type 3 or type 4, the uplink precoding matrix indication 3912 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4.

[0345] In another aspect related to indicating a rank-5 matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the precoding matrices of type 1 to 4 without limitation. For example, the uplink precoding matrix indication 2930 can include a 2-bit PG indication to indicate type 1, type 2, type 3, or type 4 based on the PG indication code point.

[0346] In addition to the 2-bit PG indication, the uplink precoding matrix indication 2930 may include two TPMI fields to indicate the first 4Tx precoding matrix and the second 4Tx precoding matrix.

[0347] exist Figure 40 In the example of , the first table 4000 depicts indicating any of the type 1, type 2, type 3, or type 4 precoding matrices without limitation. For example, for indicating a rank-5 NC precoding matrix of type 1 or type 2 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 4002 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0; and a second 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indexes 0 to 5. For indicating a rank-5 NC precoding matrix of type 3 or type 4 (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 4004 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 2-bit TPMI field to indicate one of four states associated with 4Tx rank-1 TPMI indexes 0 to 3.

[0348] For a rank-5 PC-2 precoding matrix indicating type 1 or type 2, the uplink precoding matrix indication 4006 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13. For a rank-5 PC-2 precoding matrix indicating type 3 or type 4, the uplink precoding matrix indication 4008 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-1 TPMI indices 4 to 11.

[0349] For a rank-5 PC-4 precoding matrix indicating type 1 or type 2, the uplink precoding matrix indication 4010 may include: a 2-bit PG indication; a first 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21. For a rank-5 PC-4 precoding matrix indicating type 3 or type 4, the uplink precoding matrix indication 4012 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4; and a second 4-bit TPMI field to indicate one of 16 states associated with 4Tx rank-1 TPMI indices 12 to 27.

[0350] For the rank-6 8Tx codebook, the precoding matrix can be associated with type 1, type 2, or type 3, as shown in Table 2400. Figure 40 The second table 4020 of FIG. 4020 illustrates a first aspect of an uplink precoding matrix indication 2930 for rank 6. In the second table 4020, the uplink precoding matrix indication 2930 may be configured to indicate only a type 1 precoding matrix. In such an example, the uplink precoding matrix indication 2930 may skip including a PG indication (e.g., the PG indication may be reserved or deactivated). The uplink precoding matrix indication 2930 may also include a TPMI field. Additionally, the uplink precoding matrix indication 2930 may include the same precoder restrictions, such that the first precoding matrix and the second precoding matrix may be configured to be the same (e.g., W 4Tx,r＝3 =W′ 4Tx,r＝3 ). In such examples, Figure 40The uplink precoding matrix indication 2930 associated with the second table 4020 may include a TPMI field.

[0351] like Figure 40 As shown in the second table 4020, for the rank-6 NC precoding matrix, the uplink precoding matrix indication 4022 may include a 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0.

[0352] For rank-6 PC-2 precoding matrix, the uplink precoding matrix indication 4024 may include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI index 1 to 2.

[0353] For a rank-6 PC-4 precoding matrix, the uplink precoding matrix indication 4026 may include a 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6.

[0354] In another aspect related to the rank-6 8Tx codebook, the uplink precoding matrix indication 2930 may be configured to indicate either a Type 2 precoding matrix or a Type 3 precoding matrix using only a single TPMI field included in the uplink precoding matrix indication 2930. The uplink precoding matrix indication 2930 may include a 1-bit PG indicator to indicate whether the 8Tx precoding matrix is ​​Type 2 or Type 3. In examples where only Type 2 is allowed, the PG indication may be disabled or reserved.

[0355] Additionally, the TPMI field of the uplink precoding matrix indication 2930 may include the following restrictions, such that a single TPMI field may be included in the uplink precoding matrix indication 2930:

[0356] W 4Tx,r＝2 =[W 4Tx,r＝4 ]2

[0357] In the above constraints, the pre-decoding matrix (W 4Tx,r＝4 ) are used for the second pre-decoding matrix, such as Figure 41 As shown in the first table 4100 of . For the rank-6 NC precoding matrix, the uplink precoding matrix indication 4102 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 2 or type 3. The uplink precoding matrix indication 4102 may also include a 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0358] For rank-6 PC-2 precoding matrices, the uplink precoding matrix indication 4104 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 2 or type 3. The uplink precoding matrix indication 4104 may also include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2.

[0359] For rank-6 PC-4 precoding matrices, the uplink precoding matrix indication 4106 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 2 or type 3. The uplink precoding matrix indication 4106 may also include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 3 to 4.

[0360] In another aspect related to the rank-6 8Tx codebook, the uplink precoding matrix indication 2930 can be configured to indicate only the type 2 precoding matrix or the type 3 precoding matrix with restrictions similar to those in conjunction with Figure 32 For example, the following restrictions may apply so that the second precoding matrix can be derived from the first precoding matrix included in the uplink precoding matrix indication 2930:

[0361] W 4Tx,r＝2 =[W′ 4Tx,r＝4 ]2

[0362] In the above constraints, the pre-coding matrix (W′ 4Tx,r＝4 ) is used for the second precoding matrix. For example, the first TPMI field may indicate the precoding matrix ("W 4Tx,r＝4 ”), and the second TPMI field may indicate a precoding matrix (“W′ 4Tx,r＝4 ”) for Figure 41 The second table 4110.

[0363] For the rank-6 NC precoding matrix, the uplink precoding matrix indication 4112 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 2 or type 3. The uplink precoding matrix indication 4112 may also include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0364] For the rank-6 PC-2 precoding matrix, the uplink precoding matrix indication 4114 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 2 or type 3. The uplink precoding matrix indication 4114 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2.

[0365] For the rank-6 PC-4 precoding matrix, the uplink precoding matrix indication 4116 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 2 or type 3. The uplink precoding matrix indication 4116 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 3 to 4; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 3 to 4.

[0366] In examples where only Type 2 is allowed, the PG indication may be disabled or reserved.

[0367] In another aspect related to the rank-6 8Tx codebook, the uplink precoding matrix indication 2930 can be configured to indicate only the type 1 precoding matrix with restrictions similar to those in conjunction with Figure 31 For example, two TPMI fields may be included in the uplink precoding matrix indication 2930, where the first TPMI field may correspond to the precoding matrix ("W 4Tx,r＝3 ”), and the second TPMI field may correspond to a precoding matrix (“W′ 4Tx,r＝3 ”).

[0368] exist Figure 41 In the third table 4120, the uplink precoding matrix indication 2930 may skip the PG indication (e.g., the PG indication field may be reserved or disabled). For a rank-6 NC precoding matrix, the uplink precoding matrix indication 4122 may include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0.

[0369] For the rank-6 PC-2 precoding matrix, the uplink precoding matrix indication 4124 may include: a first 1-bit TPMI field to indicate one of the two states associated with the 4Tx rank-3 TPMI index 1 to 2; and a second 1-bit TPMI field to indicate one of the two states associated with the 4Tx rank-3 TPMI index 1 to 2.

[0370] For the rank-6 PC-4 precoding matrix, the uplink precoding matrix indication 4126 may include: a first 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indexes 3 to 6; and a second 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indexes 3 to 6.

[0371] In another aspect related to the rank-6 8Tx codebook, the uplink precoding matrix indication 2930 may be configured to indicate a type 2 precoding matrix or a type 3 precoding matrix using only different TPMIs indicated by the first TPMI field and the second TPMI field of the uplink precoding matrix indication 2930. For example, the first TPMI field may indicate a precoding matrix (“W 4Tx,r＝4 ”), and the second TPMI field may indicate a precoding matrix (“W 4Tx,r＝2 ”) for Figure 42 The first table is 4200.

[0372] For the rank-6 NC precoding matrix, the uplink precoding matrix indication 4202 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 2 or type 3. The uplink precoding matrix indication 4202 may also include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indexes 0 to 5.

[0373] For a rank-6 PC-2 precoding matrix, the uplink precoding matrix indication 4204 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 2 or type 3. The uplink precoding matrix indication 4204 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13.

[0374] For the rank-6 PC-4 precoding matrix, the uplink precoding matrix indication 4206 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 2 or type 3. The uplink precoding matrix indication 4206 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-3 TPMI indices 14 to 21.

[0375] In examples where only Type 2 is allowed, the PG indication may be disabled or reserved.

[0376] In another aspect related to the rank-6 precoding matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the precoding matrices of types 1 to 3, with restrictions. In such an example, the uplink precoding matrix indication 2930 can include a 2-bit PG indication to indicate the precoding matrix type via a codepoint.

[0377] Additionally, the uplink precoding matrix indication 2930 may include a first restriction (eg, W 4Tx,r＝3 =W′ 4Tx,r＝3 ) and a second limit (e.g., W 4Tx,r＝2 =[W 4Tx,r＝4 ]2) a single TPMI field.

[0378] exist Figure 52 In the example of , the second table 4210 depicts indicating any of precoding matrix types 1 to 3 with restrictions. For example, for indicating a rank-6 NC precoding matrix of type 1 (e.g., based on a PG indication code point), the uplink precoding matrix indication 4212 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0. For indicating a rank-6 NC precoding matrix of type 2 or type 3 (e.g., based on a PG indication code point), the uplink precoding matrix indication 4214 may include: a 2-bit PG indication; and a 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0379] For a rank-6 PC-2 precoding matrix indicating type 1, the uplink precoding matrix indication 4216 may include a 2-bit PG indication and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2. For a rank-6 PC-2 precoding matrix indicating type 2 or type 3, the uplink precoding matrix indication 4218 may include a 2-bit PG indication and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2.

[0380] For a rank-6 PC-4 precoding matrix indicating type 1, the uplink precoding matrix indication 4220 may include a 2-bit PG indication and a 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6. For a rank-6 PC-4 precoding matrix indicating type 2 or type 3, the uplink precoding matrix indication 4222 may include a 2-bit PG indication and a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4.

[0381] In another aspect related to indicating a rank-6 precoding matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the precoding matrices of types 1 to 3, with restrictions. For example, the uplink precoding matrix indication 2930 can include a 2-bit PG indication to indicate type 1, type 2, or type 3 based on the PG indication code point.

[0382] In addition to the 2-bit PG indication, the uplink precoding matrix indication 2930 may include two TPMI fields to indicate the first 4Tx precoding matrix and the second 4Tx precoding matrix. In the example where the uplink precoding matrix indication 2930 indicates a type 1 precoding matrix, the first restriction (e.g., W 4Tx,r＝3 =W′ 4Tx,r＝3 ) may apply. In the example where the uplink precoding matrix indication 2930 indicates a type 2 or type 3 precoding matrix, the second restriction (e.g., W 4Tx,r＝2 =[W 4Tx,r＝4 ]2) Applicable.

[0383] exist Figure 43In the example of , table 4300 depicts indicating any of type 1, type 2, or type 3 precoding matrices with restrictions. For example, for indicating a type 1 rank-6 NC precoding matrix (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 4302 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0. For indicating a type 2 or type 3 rank-6 NC precoding matrix (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 4304 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0384] For a rank-6 PC-2 precoding matrix indicating type 1, the uplink precoding matrix indication 4306 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2. For a rank-6 PC-2 precoding matrix indicating type 2 or type 3, the uplink precoding matrix indication 4308 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2.

[0385] For a rank-6 PC-4 precoding matrix indicating type 1, the uplink precoding matrix indication 4310 may include: a 2-bit PG indication; a first 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6; and a second 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6. For a rank-6 PC-4 precoding matrix indicating type 2 or type 3, the uplink precoding matrix indication 4312 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4.

[0386] In another aspect related to indicating a rank-6 matrix, the uplink precoding matrix indication 2930 can be configured to indicate any of the precoding matrices of types 1 to 3 without limitation. For example, the uplink precoding matrix indication 2930 can include a 2-bit PG indication to indicate type 1, type 2, or type 3 based on the PG indication code point.

[0387] In addition to the 2-bit PG indication, the uplink precoding matrix indication 2930 may include two TPMI fields to indicate the first 4Tx precoding matrix and the second 4Tx precoding matrix.

[0388] exist Figure 44 In the example of , the first table 4400 depicts indicating any of type 1, type 2, or type 3 precoding matrices without limitation. For example, for indicating a type 1 rank-6 NC precoding matrix (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 4402 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0. For indicating a type 2 or type 3 rank-6 NC precoding matrix (e.g., based on a PG indication codepoint), the uplink precoding matrix indication 4404 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 3-bit TPMI field to indicate one of six states associated with 4Tx rank-2 TPMI indices 0 to 5.

[0389] For a rank-6 PC-2 precoding matrix indicating type 1, the uplink precoding matrix indication 4406 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indices 1 to 2. For a rank-6 PC-2 precoding matrix indicating type 2 or type 3, the uplink precoding matrix indication 4408 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 1 to 2; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 6 to 13.

[0390] For a rank-6 PC-4 precoding matrix indicating type 1, the uplink precoding matrix indication 4410 may include: a 2-bit PG indication; a first 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6; and a second 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6. For a rank-6 PC-4 precoding matrix indicating type 2 or type 3, the uplink precoding matrix indication 4412 may include: a 2-bit PG indication; a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4; and a second 3-bit TPMI field to indicate one of eight states associated with 4Tx rank-2 TPMI indices 14 to 21.

[0391] For the rank-7 8Tx codebook, the precoding matrix can be associated with type 1 or type 2, as shown in Table 2400. Figure 44 The second table 4420 illustrates a first aspect of the uplink precoding matrix indication 2930 for rank 7. In the second table 4420, the uplink precoding matrix indication 2930 can be configured to indicate only a type 1 precoding matrix. In such an example, the uplink precoding matrix indication 2930 can skip including a PG indication (e.g., the PG indication can be reserved or deactivated). The uplink precoding matrix indication 2930 can also include a TPMI field. Additionally, the uplink precoding matrix indication 2930 can include the following restrictions on the TPMI field:

[0392] W 4Tx,r＝3 =[W 4Tx,r＝4 ]3

[0393] In the above constraints, the pre-decoding matrix (W 4Tx,r＝4 ) are used for the second pre-decoding matrix, such as Figure 44 As shown in the second table 4420. For the rank-7 NC precoding matrix, the uplink precoding matrix indication 4422 may include a 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0394] For a rank-7 PC-2 precoding matrix, the uplink precoding matrix indication 4424 may include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2.

[0395] For a rank-7 PC-4 precoding matrix, the uplink precoding matrix indication 4426 may include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 3 to 4.

[0396] In another aspect related to the rank-7 8Tx codebook, the uplink precoding matrix indication 2930 may be configured to indicate a type-1 precoding matrix or a type-2 precoding matrix using only a single TPMI field included in the uplink precoding matrix indication 2930. The uplink precoding matrix indication 2930 may include a 1-bit PG indicator to indicate whether the 8Tx precoding matrix is ​​type-1 or type-2.

[0397] Additionally, the TPMI field of the uplink precoding matrix indication 2930 may include the following restrictions, such that a single TPMI field may be included in the uplink precoding matrix indication 2930:

[0398] W 4Tx,r＝3 =[W 4Tx,r＝4 ]3

[0399] In the above constraints, the pre-decoding matrix (W 4Tx,r＝4 ) are used for the second pre-decoding matrix, such as Figure 45 As shown in the first table 4500 of . For the rank-7 NC precoding matrix, the uplink precoding matrix indication 4502 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 4502 may also include a 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0400] For rank-7 PC-2 precoding matrices, the uplink precoding matrix indication 4504 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 4504 may also include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2.

[0401] For rank-7 PC-4 precoding matrices, the uplink precoding matrix indication 4506 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 4506 may also include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 3 to 4.

[0402] In another aspect related to the rank-7 8Tx codebook, the uplink precoding matrix indication 2930 can be configured to indicate only the type 1 precoding matrix with restrictions similar to those in conjunction with Figure 32 For example, the following restrictions may apply so that the second precoding matrix can be derived from the first precoding matrix included in the uplink precoding matrix indication 2930:

[0403] W 4Tx,r＝3 =[W′ 4Tx,r＝4 ]3

[0404] In the above constraints, the pre-coding matrix (W′ 4Tx,r＝4 ) are used for the second precoding matrix. For example, the first TPMI field may indicate the precoding matrix ("W 4Tx,r＝4 ”), and the second TPMI field may indicate a precoding matrix (“W′ 4Tx,r＝4 ”) for Figure 45 In the second table 4510, the PG indication may be disabled or reserved.

[0405] For the rank-7 NC precoding matrix, the uplink precoding matrix indication 4512 may include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0406] For the rank-7 PC-2 precoding matrix, the uplink precoding matrix indication 4514 may include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI index 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI index 1 to 2.

[0407] For the rank-7 PC-4 precoding matrix, the uplink precoding matrix indication 4516 may include: a first 1-bit TPMI field to indicate one of the two states associated with the 4Tx rank-4 TPMI index 3 to 4; and a second 1-bit TPMI field to indicate one of the two states associated with the 4Tx rank-4 TPMI index 3 to 4.

[0408] In another aspect related to the rank-7 8Tx codebook, the uplink precoding matrix indication 2930 can be configured to indicate a type 1 precoding matrix or a type 2 precoding matrix with restrictions similar to those in conjunction with Figure 45 For example, the following restrictions may apply so that the second precoding matrix can be derived from the first precoding matrix included in the uplink precoding matrix indication 2930:

[0409] W 4Tx,r＝3 =[W′ 4Tx,r＝4 ]3

[0410] In the above constraints, the pre-coding matrix (W′ 4Tx,r＝4) are used for the second precoding matrix. For example, the first TPMI field may indicate the precoding matrix ("W 4Tx,r＝4 ”), and the second TPMI field may indicate a precoding matrix (“W′ 4Tx,r＝4 ”) for Figure 45 The third table 4520.

[0411] For a rank-7 NC precoding matrix, the uplink precoding matrix indication 4522 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 4522 may also include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0412] For the rank-7 PC-2 precoding matrix, the uplink precoding matrix indication 4524 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 4524 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2.

[0413] For the rank-7 PC-4 precoding matrix, the uplink precoding matrix indication 4526 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 4526 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 3 to 4; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 3 to 4.

[0414] In another aspect related to the rank-7 8Tx codebook, the uplink precoding matrix indication 2930 may be configured to indicate only the type 1 precoding matrix without restriction. For example, the first TPMI field may indicate the precoding matrix ("W 4Tx,r＝4 ”), and the second TPMI field may indicate a precoding matrix (“W 4Tx,r＝3 ”) for Figure 46 In the first table 4600, the PG indication may be disabled or reserved.

[0415] For the rank-7 NC precoding matrix, the uplink precoding matrix indication 4602 may include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0.

[0416] For the rank-7 PC-2 precoding matrix, the uplink precoding matrix indication 4604 may include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indexes 1 to 2.

[0417] For the rank-7 PC-4 precoding matrix, the uplink precoding matrix indication 4606 may include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4; and a second 1-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6.

[0418] In another aspect related to the rank-7 8Tx codebook, the uplink precoding matrix indication 2930 may be configured to indicate only the type 1 precoding matrix without restriction. For example, the first TPMI field may indicate the precoding matrix ("W 4Tx,r＝4 ”), and the second TPMI field may indicate a precoding matrix (“W 4Tx,r＝3 ”) for Figure 46 The second table 4610.

[0419] For a rank-7 NC precoding matrix, the uplink precoding matrix indication 4612 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 4612 may also include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-3 TPMI index 0.

[0420] For a rank-7 PC-2 precoding matrix, the uplink precoding matrix indication 4614 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 4614 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2; and a second 1-bit TPMI field to indicate one of two states associated with 4Tx rank-3 TPMI indexes 1 to 2.

[0421] For the rank-7 PC-4 precoding matrix, the uplink precoding matrix indication 4616 may include a 1-bit PG indication to indicate whether the 8Tx precoding matrix is ​​type 1 or type 2. The uplink precoding matrix indication 4616 may also include: a first 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indices 3 to 4; and a second 2-bit TPMI field to indicate one of four states associated with 4Tx rank-3 TPMI indices 3 to 6.

[0422] For a rank-8 8Tx codebook, the precoding matrix may be associated with type 1, as shown in Table 2400 . Figure 47 The first table 4710 of FIG. 4 illustrates a first aspect for illustrating an uplink precoding matrix indication 2930 for rank 8. With respect to indicating a precoding matrix from a rank-8 8Tx codebook, a PG indication is not required (e.g., the PG indication may be reserved or disabled). In the first table 4710, the uplink precoding matrix indication 2930 may be configured with restrictions (e.g., W 4Tx,r＝4 =W′ 4Tx,r＝4 ). This restriction can facilitate reducing signaling overhead because the uplink precoding matrix indication 2930 can be configured to include one TPMI field to indicate the first precoding matrix and the second precoding matrix.

[0423] For a rank-8 NC precoding matrix, the uplink precoding matrix indication 4702 may include a 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0424] For rank-8 PC-2 precoding matrices, the uplink precoding matrix indication 4704 may include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 1 to 2.

[0425] For rank-8 PC-4 precoding matrices, the uplink precoding matrix indication 4706 may include a 1-bit TPMI field to indicate one of two states associated with 4Tx rank-4 TPMI indexes 3 to 4.

[0426] In another aspect related to the rank-8 8Tx codebook, the uplink precoding matrix indication 2930 may be configured without restrictions on the first precoding matrix and the second precoding matrix, such as in conjunction with Figure 47 In such an example, the uplink precoding matrix indication 2930 may be configured to include two TPMI fields to indicate the first precoding matrix and the second precoding matrix.

[0427] For the rank-8 NC precoding matrix, the uplink precoding matrix indication 4712 may include: a first 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0; and a second 1-bit TPMI field to indicate a state associated with 4Tx rank-4 TPMI index 0.

[0428] For the rank-8 PC-2 precoding matrix, the uplink precoding matrix indication 4714 may include: a first 1-bit TPMI field to indicate one of the two states associated with the 4Tx rank-4 TPMI index 1 to 2; and a second 1-bit TPMI field to indicate one of the two states associated with the 4Tx rank-4 TPMI index 1 to 2.

[0429] For the rank-8 PC-4 precoding matrix, the uplink precoding matrix indication 4716 may include: a first 1-bit TPMI field to indicate one of the two states associated with the 4Tx rank-4 TPMI index 3 to 4; and a second 1-bit TPMI field to indicate one of the two states associated with the 4Tx rank-4 TPMI index 3 to 4.

[0430] In some aspects, the non-coherent and partially coherent codebook design may include: the base station transmits a radio resource control (RRC) and a medium access control-control element (MAC-CE) that down-selects four antenna ports to be used, and then the base station transmits a DCI indicating the precoding matrix to be used for PUSCH. Therefore, four ports are selected from the 8 antenna ports via RRC and / or MAC-CE signaling, and then a 4-port codebook is applied to the selected four antenna ports. For example, for rank 1 transmission, with RRC / MAC-CE 4-port down-selection The matrix becomes Similarly, for rank 2 transmission, with RRC / MAC-CE 4-port downselect The matrix becomes Matrix. For rank 3 transmission, with RRC / MAC-CE 4-port downselect The matrix becomes Matrix (or a single matrix with subsampling). For rank 4 transmission, with RRC / MAC-CE 4-port downselect The matrix becomes a single matrix.

[0431] For a DFT codebook with an oversampling factor of 2 and a common phase, rank 1 may have 32 matrices, rank 2 may have 16 matrices, rank 3 may have 8 matrices, and rank 4 may have 8 matrices 8. In some aspects, the matrices may be expanded from a 4x4 Householder design.

[0432] Figure 48 Illustrated is an example table 4800 showing example TPMI bit fields for UL 8Tx MIMO when the maximum rank is 2, 3, or 4. The table illustrates examples of fully coherent (FC), four-antenna partially coherent (PC-4), two-antenna partially coherent (PC-2), and non-coherent (NC) transmissions. Figure 49 Illustrated is an example table 4900 showing example bit fields of the second TPMI field for 8Tx ranks 1-4 when the maximum rank is 2, 3, or 4. The second TPMI field may include information to be used with the same number of layers indicated by the first TPMI field in the DCI scheduling the PUSCH.

[0433] As presented herein, a single precoder may be used for each of ranks 5-8. In some aspects, for rank "R," a non-coherent single precoder may be applied to four ports selected from eight ports in RRC signaling or MAC-CE, and one or more additional ports may be used based on a port selection mechanism. The one or more additional ports may correspond to rank R-4, for example, for four ports indicated by the network. For the additional antenna ports, the UE may select the port with the lowest index that was not selected in the RRC signaling or MAC-CE.

[0434] For example, for rank 5, when the UE receives signaling from the base station to select antenna ports 2-3-6-7 among 8 antenna ports, the UE may select antenna port 0, which has the lowest index and is not among the four selected antenna ports. This selection may be expressed as:

[0435] Rank-5 selections are 2-3-6-7-0, and the rank-5 pre-decoder can be

[0436] Similarly, for rank 6 transmission, the UE may select antenna port 0 and antenna port 1 because they have the lowest index. This can be expressed as:

[0437] Rank 6 selects 2-3-6-7-0-1, and the rank 6 pre-decoder can be

[0438] Similarly, for rank 7 transmission, the UE may select antenna port 0, antenna port 1, and antenna port 2 because they have the lowest index. This can be expressed as:

[0439] Rank-7 selections are 2-3-6-7-0-1-4, and the rank-7 precoder can be

[0440] Similarly, for rank 8 transmission, the UE may select antenna port 0, antenna port 1, antenna port 4, and antenna port 5 in order of lowest index. This may be expressed as:

[0441] Rank-8 selects 2-3-6-7-0-1-4-5, and the rank-8 precoder can be

[0442]

[0443] In another example, four antenna ports may be indicated to the UE via RRC signaling or MAC-CE, and the UE may select one or more additional antenna ports of up to the corresponding rank based on the order indicated by the network. For example, antenna ports may be grouped into antenna port groups or antenna port sets, and each group may have a specific antenna port order. For rank "R" non-coherent transmission, a single precoder may select 4 ports in the first set + (R-4) ports in the second set based on the order of the antenna ports within the set.

[0444] For example, for rank 5 transmission, if the first set is 0-4-1-5 and the second set is 2-6-3-7, and the first set is indicated in RRC signaling or MAC-CE, the UE can select antenna port 0, antenna port 4, antenna port 1, antenna port 5, and antenna port 2, because antenna port 2 is the first antenna port in the second set. This selection can be expressed as:

[0445] Rank-5 selections are 0-4-1-5-2, and the rank-5 precoder can be

[0446] For rank 6 transmission, the UE may select antenna ports 0-4-1-5-2-6. For rank 7 transmission, the UE may select antenna ports 0-4-1-5-2-6-3. For rank 8 transmission, the UE may select antenna ports 0-4-1-5-2-6-3-7. Examples of pre-decoders for ranks 6, 7, and 8 may be:

[0447]

[0448]

[0449] In some aspects, there may be two default sets of four antenna ports. The UE may apply the default set unless an antenna port set is configured for the UE, e.g., signaled to the UE by the base station. In some aspects, the default set may be antenna ports 0-4-1-5 and antenna ports 2-6-3-7.

[0450] In some aspects, coherent port pairs may be provided. Port pairs may be configured, defined, or fixed. For example, for 8 antenna ports, the first coherent antenna port pair may be 0-4, the second coherent antenna port pair may be 1-5, the third coherent antenna port pair may be 2-6, and the fourth coherent antenna port pair may be 3-7. Two precoders may be provided for each of ranks 5-8.

[0451] In some aspects, a 4-layer precoder may be applied to the 4 antenna ports down-selected by RRC signaling or MAC-CE + additional (R-4) layers that use port pairs not included in the down-selected 4 ports and follow a specific order. For example, the selection order among the port pairs may be 0-4, 1-5, 2-6, 3-7.

[0452] Commonalities can be applied. For example, the following commonalities can be applied for an additional layer: And the following common phases apply for the additional two layers: [1;-1]], [1; [j]]. In the example where the downwardly selected ports are 0-4-1-5, then for rank 5 transmission, the UE may use a 4-layer precoder for antenna ports 0-4-1-5 and may use an additional layer on ports 2-6, which are the next port pair in the order of port pairs. For rank 6 transmission, the UE may use a 4-layer precoder for antenna ports 0-4-1-5 and may use an additional two layers on ports 2-6, which are the next port pair in the order of port pairs. For rank 7 transmission, the UE may use a 4-layer precoder for antenna ports 0-4-1-5 and may use an additional two layers on ports 2-6 and one layer on ports 3-7 (which are the next port pair). For rank 8 transmission, the UE may use a 4-layer precoder for antenna ports 0-4-1-5 and may use an additional two layers on ports 2-6 and an additional two layers on ports 3-7. Figure 50 Example precoding matrices for rank 5-8 examples are illustrated, including, for example, a precoding matrix 5000 for rank 5, a precoding matrix 5010 for rank 6, a precoding matrix 5020 for rank 7, and a precoding matrix 5030 for rank 8.

[0453] In some aspects, two 4-port sets may be configured for a UE via RRC signaling and / or MAC-CE. For transmission of rank R, the UE may apply a 4-layer precoder to the 4 ports in the first set signaled to the UE, and may transmit the R-4 layers in order using antenna port pairs in the second set. For example, the first set may be antenna ports 0-4, 1-5, and the second set may be antenna ports 2-6, 3-7 in order.

[0454] In some aspects, there may be fixed or configured groups of coherent antenna ports. For example, a first group or set of coherent antenna ports may be antenna ports 0-4-1-5, and a second group of coherent antenna ports may be antenna ports 2-6-3-7. Two precoders may be provided for each of ranks 5, 6, 7, and 8. The UE may apply coherent combining using an orthogonal sequence of length 4 for the antenna port group. For example, the orthogonal sequence of length 4 for the antenna port group may be:

[0455] {[1; 1; 1; 1],[1;-1; 1;-1],[1; 1;-1;-1],[1;-1,-1,1]} or

[0456] {[1;1;j;j],[1;-1;j;-j],[1;1;-j;-j],[1;-1,-j,j]}

[0457] For rank R transmission, ceil(R / 2) layers may be transmitted for the first port group, and floor(R / 2) layers may be transmitted for the second port group.

[0458] For example, for rank 5 transmission, the UE may transmit 3 layers using antenna ports from the first antenna port group and 2 layers using antenna ports from the second antenna port group. For rank 6 transmission, the UE may transmit 3 layers using antenna ports from the first antenna port group and 3 layers using antenna ports from the second antenna port group. For rank 7 transmission, the UE may transmit 4 layers using antenna ports from the first antenna port group and 3 layers using antenna ports from the second antenna port group. For rank 8 transmission, the UE may transmit 4 layers using antenna ports from the first antenna port group and 4 layers using antenna ports from the second antenna port group. The UE may apply scaling to the transmission. The UE may apply a first scaling to the transmission from the antennas in the first antenna port group and may apply a second scaling to the transmission from the antennas in the second antenna port group. For example, the UE may apply the first scaling for the first antenna port group And a second scaling may be applied for a second port group The scaling is based on the number of layers or the number of antenna ports used from the corresponding antenna port group, e.g. And for the second antenna port group Figure 51 Two example predecoders for each of ranks 5, 6, 7, and 8 are illustrated, including, for example, predecoders 5102 and 5104 for rank 5, predecoders 5106 and 5108 for rank 6, predecoders 5110 and 5112 for rank 7, and predecoders 5114 and 5116 for rank 8.

[0459] In some aspects, for rank R, the UE may transmit using 4 layers for the first antenna port group and R-4 layers for the second antenna port group. In this example, for rank 5 transmission, the UE may transmit 4 layers using antenna ports from the first antenna port group and transmit 1 layer using antenna ports from the second antenna port group. For rank 6 transmission, the UE may transmit 4 layers using antenna ports from the first antenna port group and transmit 2 layers using antenna ports from the second antenna port group. For rank 7 transmission, the UE may transmit 4 layers using antenna ports from the first antenna port group and transmit 3 layers using antenna ports from the second antenna port group. For rank 8 transmission, the UE may transmit 4 layers using antenna ports from the first antenna port group and transmit 4 layers using antenna ports from the second antenna port group. In this example, the UE may apply a scaling factor for transmissions using antennas in the first port group. And apply the scaling factor for the antennas in the second port group Figure 52 Two example predecoders for each of ranks 5, 6, 7, and 8 are illustrated, including, for example, predecoders 5202 and 5204 for rank 5, predecoders 5206 and 5208 for rank 6, predecoders 5210 and 5212 for rank 7, and predecoders 5214 and 5216 for rank 8.

[0460] In some aspects, a DFT codebook with an oversampling factor of 2 and using a common phase may be used for 8Tx UL MIMO. For example, precoding for 8Tx UL MIMO transmissions may be based on a subsampled version of the 8Tx downlink codebook, e.g., where N1=4, N2=1, O1=2, O2=1. For the QPSK element, even i1 values ​​may be used, which provides 8 precoders for ranks 5 and 6, and 4 precoders for ranks 7 and 8. Alternatively, in the case of 8-PSK, the rank 7 and rank 8 codebooks may each have 8 precoders. Figure 53 8 pre-decoders 5302 for rank 5, 8 pre-decoders 5304 for rank 6, 4 or 8 pre-decoders 5306 for rank 7, and 4 or 8 pre-decoders 5308 for rank 8 are illustrated. Figure 53 In the example, and

[0461] In another example, the codebook for ranks 5-8 may be based on a codebook optimized for spatially uncorrelated channels. For example, the codebook may be based on a combination of two 4×4 Householder matrices that may be used for DL ​​4Tx (which may be referred to as stacking). The UE may apply co-phasing between two different antenna groups. The co-phasing parameter may be expressed as

[0462] For example, the codebook for rank 5-8 transmission may be based on:

[0463]

[0464] In this matrix, or {1,-1}, and [H 4,l ] (r) is a 4×r matrix with r columns, selected from H 4,l The 4 columns of , r = 1, 2, 3, 4, which correspond to ranks 5, 6, 7, 8.

[0465] To construct this Householder-based codebook, the common phase parameter n=0,…N-1 and u l， l=0,…,L-1 is based on the good rank 1 vector w l , l=0,…,L-1 set selection.

[0466] Then, the corresponding Householder vector u is obtained l , so that the first column of the Householder matrix is ​​equal to w l Then, using the Householder vector H 4,l The rank-4 codebook is obtained by using a 4×4 Householder matrix. For example, the UE may use a 4Tx downlink precoding matrix with L=16 elements and the following Householder matrix / vector.

[0467]

[0468] In some aspects, a UE may use a subset of 4Tx precoders with a common phase to construct an 8Tx precoder for an 8Tx UL MIMO transmission. In some aspects, a 4Tx precoder (e.g., ) can be a DL 4Tx or other precoder. In some aspects, the 4Tx precoder can be a precoder for a RAT other than for UL MIMO transmissions. For example, a UE can transmit an NR UL MIMO transmission using an 8Tx precoder that uses a subset of the LTE DL 4Tx precoder with a common phase to construct an 8Tx precoder for the NR 8Tx UL MIMO transmission.

[0469] As shown below, there may be

[0470] For the common phase, there are four options. Figure 54 The following example is illustrated: W 5402 for the first option (0), e.g. W for the second option (1), e.g. W for the third option (2), e.g. and W for the fourth option (3), e.g. In this example:

[0471]

[0472] For options (0), (1), and (2), one bit of common phase reporting may be used. For option (3), four bits of common phase reporting may be used. Figure 54 It is shown that a first portion 5410 may be used for rank 5 transmission, an extended portion 5412 may be used for rank 6 transmission, a further extended portion 5414 may be used for rank 7 transmission, and a full set of precoders 5416 may be used for rank 8 transmission. Although illustrated for the first option, the portion using precoders based on rank may be applied similarly to 5404, 5406, and 5408.

[0473] The following table provides mapping of the first TPMI field for UL 8Tx MIMO with a rank greater than 4 (eg, rank 5, rank 6, rank 7, or rank 8).

[0474] In some aspects, 4-6-7-8 bits are shown for codebook subset restrictions NC, NC / PC-2, NC / PC-2 / PC-4, and NC / PC-2 / PC-4 / FC. As illustrated, for rank 7 and 8 fully coherent (FC) codebooks, four precoders are used for each rank.

[0475]

[0476]

[0477]

[0478] The following table illustrates the bit mapping of the second TPMI field for 8Tx rank 1-8 UL MIMO transmission, for example, when maxRank>4 (e.g., maxRank=5, 6, 7, or 8). The mapping has the same number of layers indicated by the first TPMI field. For rank 7-8 fully coherent codebooks, four precoders are used.

[0479]

[0480]

[0481] The following table illustrates another example bit-field mapping for the first TPMI field for UL 8Tx MIMO when maxRank > 4 (maxRank = 5, 6, 7, or 8). In this example, bits 4-6-7-8 are used for codebook subset restrictions NC, NC / PC-2, NC / PC-2 / PC-4, and NC / PC-2 / PC-4 / FC. For rank 7-8 fully coherent codebooks, eight precoders can be used.

[0482]

[0483]

[0484] The following table illustrates the bit mapping of the second TPMI field for 8Tx rank 1-8 UL MIMO transmission, for example, when maxRank>4 (e.g., maxRank=5, 6, 7, or 8). This mapping has the same number of layers as indicated by the first TPMI field in the table above. For rank 7-8 fully coherent codebooks, eight precoders are used.

[0485]

[0486]

[0487] Different types of devices may have different antenna layouts to support 8Tx. For example, a UE may have a different antenna layout than an indoor customer premises equipment (CPE). Due to coherence capabilities, 8Tx antennas may be configured with multiple groups. Various aspects presented herein facilitate enabling more antenna port configurations for UL 8Tx transmissions (such as 8Tx PUSCH transmissions). For example, 8Tx transmissions may be based on multiple antenna groups. The number of ports in each antenna group may be the same or different. In some aspects, the number of groups may be greater than 2. TPMI and RI indications may be based on active antenna groups.

[0488] Multiple layers of UL MIMO transmission can be transmitted using multiple subsets of coherent Tx. For example, 8Tx can be based on a combination of two Tx subsets, such as 4Tx + 4Tx. For example, 4Tx + 4Tx can refer to a first set of four antenna ports and a second set of four antenna ports. Figure 55A An example grouping of 8 antenna ports of UE 5506 into a first group of four antennas 5502 and a second group of four antennas 5504 is illustrated. Transmissions from antenna ports in each subset of the 8 antenna ports can be coherent, for example, transmissions within antenna group 5502 can be coherent, and transmissions within antenna group 5504 can be coherent. Multiple layers from rank 5 to rank 8 can be transmitted using different combinations of antenna port groups.

[0489] For example, for layer 1 sending, use Figure 55AFor the 4Tx+4Tx antenna port grouping in 5500, one layer may be transmitted from one antenna port group (e.g., 5502), and no layer may be transmitted from another antenna port group (e.g., 5504). Similarly, one layer may be transmitted from one antenna port group (e.g., 5504), and no layer may be transmitted from another antenna port group (e.g., 5502). This option can be expressed as:

[0490] 1 layer: 1 layer -> 4 Tx, 0 layer -> 4 Tx

[0491] In the 2-layer example, 2 layers may be transmitted from one antenna port group and no layers may be transmitted from the other antenna port group, or 1 layer may be transmitted from each antenna port group. This example may be represented as:

[0492] 2 layers: 0 layers -> 4Tx, 2 layers -> 4Tx; 1 layer -> 4Tx, 1 layer -> 4Tx

[0493] In the 3-layer example, 3 layers may be transmitted from one antenna port group and no layers may be transmitted from another antenna port group, or 1 layer may be transmitted from one antenna port group and 2 layers may be transmitted from another antenna port group. This example can be expressed as:

[0494] 3-layer: 0 layers -> 4Tx, 3 layers -> 4Tx; 1 layer -> 4Tx, 2 layers -> 4Tx

[0495] In the 4-layer example, 4 layers may be transmitted from one antenna port group and no layers may be transmitted from another antenna port group, or 1 layer may be transmitted from one antenna port group and 3 layers may be transmitted from another antenna port group, or 2 layers may be transmitted from each antenna port group. This example can be expressed as:

[0496] 4 layers: 0 layers -> 4Tx, 4 layers -> 4Tx; 1 layer -> 4Tx, 3 layers -> 4Tx; 2 layers ->

[0497] 4Tx, 2 layers -> 4Tx

[0498] In the 5-layer example, 1 layer may be transmitted from one antenna port group and 4 layers may be transmitted from another antenna port group, or 2 layers may be transmitted from one antenna port group and 3 layers may be transmitted from another antenna port group. This example can be expressed as:

[0499] 5-layer: 1 layer -> 4Tx, 4 layers -> 4Tx; 2 layers -> 4Tx, 3 layers -> 4Tx

[0500] In the 6-layer example, 2 layers may be transmitted from one of the antenna port groups and 4 layers may be transmitted from another antenna port group, or 3 layers may be transmitted from each of the antenna port groups. This example may be represented as:

[0501] 6-layer: 2 layers -> 4Tx, 4 layers -> 4Tx; 3 layers -> 4Tx, 3 layers -> 4Tx

[0502] In the 7-layer example, 3 layers can be transmitted from one antenna port group and 4 layers can be transmitted from another antenna port group. This example can be represented as:

[0503] 7-layer: 3 layers -> 4Tx, 4 layers -> 4Tx

[0504] In the 8-layer example, 4 layers can be transmitted from one antenna port group and 4 layers can be transmitted from another antenna port group. This example can be represented as:

[0505] 8 layers: 4 layers -> 4Tx, 4 layers -> 4Tx

[0506] Figure 55B Another example of antenna port grouping 5525 for a device with 8 antenna ports is illustrated, where a first group of antenna ports 5508 has two antenna ports, a second group of antenna ports (e.g., 5512) has two antenna ports, and a third group of antenna ports (e.g., 5510) has four antenna ports. Figure 55A In the example of , multiple layers can be sent using multiple subsets of coherent Tx. However, in Figure 55B In [1], 8Tx consists of three Tx subsets: 2Tx + 2Tx + 4Tx. Within each subset of antenna ports, transmission is coherent. Multiple layers from rank 5 to rank 8 can be transmitted using various possible combinations of layers from different antenna groups.

[0507] One layer can be transmitted by not transmitting a layer from one of the two-antenna groups (e.g., 5508 and 5512) and transmitting one layer from the four-antenna group (e.g., 5510). Alternatively, one layer can be transmitted from one of the two-antenna groups (e.g., 5508 or 5512) but not from the four-antenna group. This example can be expressed as:

[0508] 1 layer: 0 layers -> 2Tx, 0 layers -> 2Tx, 1 layer -> 4Tx; 0 layers -> 2Tx, 1 layer ->

[0509] 2Tx, 0 layers -> 4Tx

[0510] Two-layer transmission can be performed by not transmitting a layer from one of the two-antenna groups (e.g., 5508 and 5512) and transmitting two layers from the four-antenna group (e.g., 5510). Alternatively, one layer can be transmitted from one of the two-antenna groups (e.g., 5508 or 5512) and one layer can be transmitted from the four-antenna group. Alternatively, one layer can be transmitted from each of the two-antenna groups (e.g., 5508 or 5512) and no layer can be transmitted from the four-antenna group (e.g., 5510). This example can be expressed as:

[0511] 2 layers: 0 layers -> 2Tx, 0 layers -> 2Tx, 2 layers -> 4Tx; 0 layers -> 2Tx, 1 layer ->

[0512] 2Tx, 1 layer -> 4Tx; 1 layer -> 2Tx, 1 layer -> 2Tx, 0 layer -> 4Tx

[0513] 3-layer transmission can be performed by not transmitting a layer from one of the two-antenna groups (e.g., 5508 and 5512) and transmitting 3 layers from the four-antenna group (e.g., 5510). Alternatively, 1 layer can be transmitted from one of the two-antenna groups (e.g., 5508 or 5512), and 2 layers can be transmitted from the four-antenna group. Alternatively, 1 layer can be transmitted from each of the antenna groups (e.g., 5508, 5512, and 5510). This example can be expressed as: 3 layers: 0 layer -> 2Tx, 0 layer -> 2Tx, 3 layers -> 4Tx; 0 layer -> 2Tx, 1 layer ->

[0514] 2Tx, 2 layers -> 4Tx; 1 layer -> 2Tx, 1 layer -> 2Tx, 1 layer -> 4Tx

[0515] 4-layer transmission can be performed by not transmitting a layer from one of the two-antenna groups (e.g., 5508 and 5512) and transmitting 4 layers from the four-antenna group (e.g., 5510). Alternatively, 1 layer can be transmitted from one of the two-antenna groups (e.g., 5508 or 5512), and 3 layers can be transmitted from the four-antenna group. Alternatively, 1 layer can be transmitted from each of the two-antenna groups (e.g., 5508 and 5512), and 2 layers can be transmitted from the four-antenna group 5510. This example can be expressed as: 4 layers: 0 layer -> 2Tx, 0 layer -> 2Tx, 4 layers -> 4Tx; 0 layer -> 2Tx, 1 layer ->

[0516] 2Tx, 3 layers -> 4Tx; 1 layer -> 2Tx, 1 layer -> 2Tx, 2 layers -> 4Tx

[0517] 5-layer transmission can be performed by transmitting 1 layer from one of the two-antenna groups (e.g., 5508 or 5512) and transmitting 4 layers from the four-antenna group (e.g., 5510). Alternatively, 1 layer can be transmitted from each of the two-antenna groups (e.g., 5508 and 5512), and 3 layers can be transmitted from the four-antenna group 5510. Alternatively, 1 layer can be transmitted from one of the two-antenna groups (e.g., 5508), 2 layers can be transmitted from the other two-antenna group (e.g., 5512), and 2 layers can be transmitted from the four-antenna group 5510. This example can be expressed as: 5 layers: 0 layer -> 2Tx, 1 layer -> 2Tx, 4 layers -> 4Tx; 1 layer -> 2Tx, 1 layer ->

[0518] 2Tx, 3 layers -> 4Tx; 1 layer -> 2Tx, 2 layers -> 2Tx, 2 layers -> 4Tx

[0519] 6-layer transmission can be performed by transmitting 2 layers from one of the two-antenna groups (e.g., 5508 or 5512) and 4 layers from the four-antenna group (e.g., 5510). Alternatively, 1 layer can be transmitted from each of the two-antenna groups (e.g., 5508 and 5512), and 4 layers can be transmitted from the four-antenna group 5510. Alternatively, 2 layers can be transmitted from each of the two-antenna groups (e.g., 5508 and 5512), and 2 layers can be transmitted from the four-antenna group 5510. This example can be expressed as: 6 layers: 0 layer -> 2Tx, 2 layers -> 2Tx, 4 layers -> 4Tx; 1 layer -> 2Tx, 1 layer ->

[0520] 2Tx, 4 layers -> 4Tx; 2 layers -> 2Tx, 2 layers -> 2Tx, 2 layers -> 4Tx

[0521] The 7-layer transmission can be transmitted by transmitting 1 layer from one of the two antenna groups (e.g., 5508), transmitting 2 layers from the other two antenna group 5512, and transmitting 4 layers from the four antenna group 5510. This example can be expressed as:

[0522] 7 layers: 1 layer -> 2Tx, 2 layers -> 2Tx, 4 layers -> 4Tx

[0523] The 8-layer transmission can be sent by sending 2 layers from each of the two-antenna groups (e.g., 5508 and 5512) and sending 4 layers from the four-antenna group 5510. This example can be represented as:

[0524] 8 layers: 2 layers -> 2Tx, 2 layers -> 2Tx, 4 layers -> 4Tx

[0525] Figure 55CAnother example of antenna port grouping 5550 for a device with 8 antenna ports is illustrated, which groups the 8 antenna ports into four groups of two antenna ports, such as 5514, 5516, 5518, and 5520. Figure 55A and 55B In the example above, multiple layers can be transmitted using multiple subsets of coherent Tx. 8Tx can include three Tx subsets: 2Tx + 2Tx + 2Tx + 2Tx. Within each subset of antenna ports, transmission is coherent. Multiple layers from rank 5 to rank 8 can be transmitted using various possible combinations of layers from different antenna groups.

[0526] 1 layer transmission can be sent by transmitting 1 layer from one of the four antenna groups. This example can be expressed as:

[0527] 1 layer: 0 layers -> 2Tx, 0 layers -> 2Tx, 0 layers -> 2Tx, 1 layer -> 2Tx

[0528] 2-layer transmission can be sent by sending 2 layers from one of the four antenna groups, or by sending 1 layer from the first group and 1 layer from the second group. This example can be expressed as:

[0529] 2 layers: 0 layers -> 2Tx, 0 layers -> 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx

[0530] A 3-layer transmission can be sent by sending 1 layer from the first group, 1 layer from the second group, and 1 layer from the third group. This example can be expressed as:

[0531] 3 layers: 0 layers -> 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx

[0532] A 4-layer transmission can be sent by sending 1 layer from each antenna group. This example can be expressed as:

[0533] 4 layers: 1 layer -> 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx;

[0534] A 5-layer transmission can be sent by sending 1 layer from the first group, 2 layers from the second group, and 2 layers from the third group. Alternatively, a 5-layer transmission can be sent by sending 1 layer from the first, second, and third groups, and 2 layers from the fourth group. This example can be expressed as:

[0535] 5 layers: 0 layers -> 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx, 2 layers -> 2Tx; 1 layer ->

[0536] 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx

[0537] A 6-layer transmission can be sent by sending 2 layers from the first group, 2 layers from the second group, and 2 layers from the third group. Alternatively, a 5-layer transmission can be sent by sending 1 layer from the first group, 1 layer from the second group, 2 layers from the third group, and 2 layers from the fourth group. This example can be expressed as:

[0538] 6 layers: 0 layers -> 2Tx, 2 layers -> 2Tx, 2 layers -> 2Tx, 2 layers -> 2Tx; 1 layer ->

[0539] 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx, 2 layers -> 2Tx

[0540] The 7-layer transmission can be sent by sending 1 layer from the first group, 2 layers from the second group, 2 layers from the third group, and 2 layers from the fourth group. This example can be expressed as:

[0541] 7 layers: 1 layer -> 2Tx, 2 layers -> 2Tx, 2 layers -> 2Tx, 2 layers -> 2Tx;

[0542] The 8-layer transmission can be sent by sending 2 layers from the first group, 2 layers from the second group, 2 layers from the third group, and 2 layers from the fourth group. This example can be expressed as:

[0543] 8 layers: 2 layers -> 2Tx, 2 layers -> 2Tx, 2 layers -> 2Tx, 2 layers -> 2Tx;

[0544] In some aspects, multiple layers can be transmitted using multiple subsets of coherent transmissions. In some aspects, 8Tx can include a mix of partially coherent transmissions and non-coherent transmissions. For example, 8Tx = 1Tx + 1Tx + 2Tx + 4Tx. Multiple layers from rank 5 to rank 8 can be transmitted using various combinations of antenna groups.

[0545] 1 layer transmission can be sent by sending 1 layer from one of the two antenna port groups. This example can be expressed as:

[0546] 1 layer: 0 layers -> 2Tx, 0 layers -> 2Tx, 0 layers -> 2Tx, 1 layer -> 2Tx; 0 layers -> 2Tx, 0 layers -> 2Tx, 1 layer -> 2Tx, 0 layers -> 2Tx; 0 layers -> 2Tx, 1 layer ->

[0547] 2Tx, 0 layers -> 2Tx, 0 layers -> 2Tx;

[0548] 2-layer transmission can be sent by sending 2 layers from one of the two antenna port groups. This example can be expressed as:

[0549] 2 layers: 0 layers -> 2Tx, 0 layers -> 2Tx, 0 layers -> 2Tx, 2 layers -> 2Tx;

[0550] 3-layer transmission can be performed by transmitting 1 layer from one of the two antenna port groups and transmitting 2 layers from the other of the two antenna port groups. This example can be expressed as:

[0551] 3 layers: 0 layers -> 2Tx, 0 layers -> 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx;

[0552] 4 layers of transmission can be sent by sending 1 layer from the first two antenna port group, 1 layer from the second two antenna port group, and 2 layers from the third two antenna port group. This example can be expressed as:

[0553] 4 layers: 0 layers -> 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx

[0554] 5-layer transmission can be sent by transmitting 1 layer from two antenna ports and transmitting four layers from another antenna port group. Alternatively, 2 layers can be transmitted from the two antenna port group, and 3 layers can be transmitted from the four antenna port group. Alternatively, 1 layer can be transmitted from the first two-antenna port group, 1 layer can be transmitted from the second antenna port group, and 3 layers can be transmitted from the third antenna port group. Alternatively, 5-layer transmission can be sent by transmitting 1 layer from the first two-antenna port group, 1 layer from the second two-antenna port group, 1 layer from the third two-antenna port group, and 2 layers from the fourth two-antenna port group. This example can be expressed as:

[0555] 5 layers: 0 layers -> 2Tx, 0 layers -> 2Tx, 1 layer -> 2Tx, 4 layers -> 2Tx; 0 layers -> 2Tx, 0 layers -> 2Tx, 2 layers -> 2Tx, 3 layers -> 2Tx; 0 layers -> 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx, 3 layers -> 2Tx; 0 layers -> 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx, 2 layers -> 2Tx; 1 layer -> 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx, 2 layers ->

[0556] 2Tx;

[0557] 6-layer transmission may be transmitted by transmitting 2 layers from two antenna ports and four layers from another antenna port group. Alternatively, 1 layer may be transmitted from the first two-antenna port group, 1 layer may be transmitted from the second antenna port group, and 4 layers may be transmitted from the third antenna port group. Alternatively, 1 layer may be transmitted from the first two-antenna port group, 2 layers may be transmitted from the second antenna port group, and 3 layers may be transmitted from the third antenna port group. Alternatively, 5-layer transmission may be transmitted by transmitting 1 layer from the first two-antenna port group, 1 layer from the second two-antenna port group, 1 layer from the third two-antenna port group, and 3 layers from the fourth two-antenna port group. Alternatively, 5-layer transmission may be transmitted by transmitting 1 layer from the first two-antenna port group, 1 layer from the second two-antenna port group, 2 layers from the third two-antenna port group, and 2 layers from the fourth two-antenna port group. This example may be represented as:

[0558] 6 layers: 0 layers -> 2Tx, 0 layers -> 2Tx, 2 layers -> 2Tx, 4 layers -> 2Tx; 0 layers -> 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx, 4 layers -> 2Tx; 0 layers -> 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx, 3 layers -> 2Tx; 1 layer -> 2Tx, 1 layer -> 2Tx, 1 layer -> 2Tx, 3 layers -> 2Tx; 1 layer -> 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx, 2 layers ->

[0559] 2Tx;

[0560] For example, 7 layers of transmission can be transmitted by transmitting 1 layer from the first two-antenna port group, 1 layer from the second two-antenna port group, and 4 layers from the third two-antenna port group. Alternatively, 1 layer can be transmitted from the two-antenna port group, 1 layer can be transmitted from the second two-antenna port group, 2 layers can be transmitted from the third two-antenna port group, and 3 layers can be transmitted from the fourth two-antenna port group. This example can be expressed as:

[0561] 7 layers: 0 layers -> 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx, 4 layers -> 2Tx; 1 layer ->

[0562] 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx, 3 layers -> 2Tx;

[0563] For example, 8 layers of transmission can be transmitted by transmitting 1 layer from the first two-antenna port group, 1 layer from the second two-antenna port group, 2 layers from the third two-antenna port group, and 4 layers from the fourth two-antenna port group. Alternatively, 1 layer can be transmitted from the two-antenna port group, 1 layer can be transmitted from the second two-antenna port group, 2 layers can be transmitted from the third two-antenna port group, and 3 layers can be transmitted from the fourth two-antenna port group. This example can be expressed as:

[0564] 8 layers: 1 layer -> 2Tx, 1 layer -> 2Tx, 2 layers -> 2Tx, 4 layers -> 2Tx;

[0565] In some aspects, in the case of multiple coherent antenna subsets, the UE may receive a two-stage indication for TPMI and RI. Figure 55E An example communication flow between a UE 5506 and a network node 5522, such as a base station, is illustrated. As a first step, at 5524, the network may indicate which antenna groups are active. The field size of this indication may be equal to the number of antenna groups. After indicating the active antenna groups, at 5526, the network may send the TPMI and RI for each of the active antenna groups. The network may skip providing the UE with TPMI or RI indications for inactive antenna groups.

[0566] For example, for Figure 55C For the grouping options shown, e.g., 8Tx = 2Tx + 2Tx + 4Tx, for a total rank of 5 and configurations of 0 layers -> 2Tx, 2 layers -> 2Tx, and 3 layers -> 2Tx, for the first phase, e.g., at 5524, the network can use three bits to indicate antenna group activity. For example, "0 1 1" indicates that the last two antenna groups are active and the first antenna group is inactive. Then, in the second phase, three bits can indicate the TPMI and RI of the second antenna group, and six bits can indicate the TPMI and RI of the third antenna group. Figure 55D An example table 5575 showing an example bit field mapping for 2-port TPMI is illustrated. The following table illustrates example bit fields for 4-port TPMI.

[0567]

[0568]

[0569] In some aspects, to reduce TPMI overhead, the bit width of the precoding information and layer number fields can be reduced. For example, the precoding information and layer number fields for 8Tx can have a reduced bit width relative to such fields for 4Tx. For example, the TPMI corresponding to the antenna ports (e.g., Tx ports) in the coherent transmit port subset can be included.

[0570] In some aspects, the precoder for each antenna group may reuse a 2-port precoder or a 4-port precoder or a codebook subset for 2Tx or 4Tx, rather than having a separate precoder for 8Tx. The precoder in each antenna group may be scaled by factors such as To scale, where N G is the number of ports in the antenna group.

[0571] For example, for Figure 55C For the grouping option in (e.g., 8Tx=2Tx+2Tx+4Tx), the scaling factor applied to the transmission of the first set of two antenna ports 5508 and the second set of two antenna ports (e.g., 5512) will be (For example, 8 / N G is 4), and the scaling factor for a four-antenna port group (e.g., 5510) will be An example pre-decoder for a two antenna port group (e.g., 5508) may be An example pre-decoder for a four antenna port group (e.g., 5510) may be

[0572] In some aspects, the UE may indicate the coherence assumption to the network. Figure 55E , at 5523, the UE 5506 may send an indication of the coherence assumption. In some aspects, the UE may indicate the coherence assumption in a report of UE capabilities, for example, the UE may indicate that it supports the coherence assumption capability.

[0573] In some aspects, the SRS configuration for UL codebook-based PUSCH transmissions may be based on antenna port groups. In some aspects, ports from different antenna groups may be configured in one SRS resource, and each port may be distinguished using a different cyclic shift and a different comb index. Figure 56A Diagram 5600 illustrates SRS resources 5606 configured for antenna port 5608 from antenna port group 1 5602 and also configured for antenna port 5610 from antenna port group 2 5604. In some aspects, ports from different antenna groups may each be configured with different SRS resources. Figure 56B Diagram 5650 illustrates SRS resources 5612 configured separately for antenna ports from antenna port group 1 5602 and SRS resources 5614 configured for antenna ports from antenna port group 2 5604. This allows for greater transmit power per antenna port compared to configuring ports from different antenna groups in one SRS resource.

[0574] Figure 57A5700 is a flow chart of a method of wireless communication. The method may be performed by a UE (eg, UE 104, 350; device 5904). The method may enable the UE to transmit UL MIMO transmissions using various precoding options for 8Tx.

[0575] At 5704, the UE receives control signaling for uplink MIMO transmission, the control signaling including the first TPMI field and the second TPMI field and the SRS resource set indicator. The reception can be performed, for example, by the codebook processing component 198, the transceiver 5922, and / or the antenna 5980. The codebook processing component 198 can be a component of the UE 104, 350, or the device 5904.

[0576] At 5708, the UE transmits an uplink MIMO transmission precoded with an 8-port uplink MIMO precoder based on a 4-port uplink MIMO codebook and a mapping indicated by one or more of the first TPMI field, the second TPMI field, or the SRS resource set indicator. The transmission may be performed, for example, by the codebook processing component 198, the transceiver 5922, and / or the antenna 5980. The codebook processing component 198 may be a component of the UE 104, 350, or the device 5904. The transmission may be based on a combination of Figures 4 to 62 Pre-decoding can be performed in any of the above aspects.

[0577] Figure 57B 5750 is a flow chart of a method of wireless communication. The method may be performed by a UE (eg, UE 104, 350; device 5904). The method may enable the UE to transmit UL MIMO transmissions using various precoding options for 8Tx.

[0578] At 5704, the UE receives control signaling for uplink MIMO transmission, the control signaling including the first TPMI field and the second TPMI field and the SRS resource set indicator. The reception can be performed, for example, by the codebook processing component 198, the transceiver 5922, and / or the antenna 5980. The codebook processing component 198 can be a component of the UE 104, 350, or the device 5904.

[0579] At 5708, the UE transmits an uplink MIMO transmission precoded with an 8-port uplink MIMO precoder based on a 4-port uplink MIMO codebook and a mapping indicated by one or more of the first TPMI field, the second TPMI field, or the SRS resource set indicator. The transmission may be performed, for example, by the codebook processing component 198, the transceiver 5922, and / or the antenna 5980. The codebook processing component 198 may be a component of the UE 104, 350, or the device 5904. The transmission may be based on a combination of Figures 4 to 62 Pre-decoding can be performed in any of the above aspects.

[0580] In some aspects, the UE may construct an 8-port precoding matrix based on a 4-port uplink MIMO codebook and a mapping indicated by one or more of the first TPMI field, the second TPMI field, or the SRS resource set indicator at 5706. The construction may be performed, for example, by the codebook processing component 198. The codebook processing component 198 may be a component of the UE 104, 350, or the device 5904.

[0581] The SRS resource set indicator may indicate a precoding matrix type, and the mapping from the 4-port uplink MIMO codebook to the 8-port precoding matrix may be indicated by a combination of the SRS resource set indicator, the first TPMI field, and the second TPMI field. The first TPMI field may indicate a first rank and a first precoding matrix indication, and the second TPMI field may indicate a second precoding matrix indication, the second rank being based on the first rank indicated in the first TPMI field and the precoding matrix type indicated by the SRS resource set indicator. In some aspects, the control signaling may also include: a first SRI indicating a first SRS resource associated with the first TPMI field; and a second SRI indicating a second SRS resource associated with the second TPMI field.

[0582] In some aspects, the control signaling may further include a first SRI and a second SRI, and the mapping from the 4-port uplink MIMO codebook to the 8-port precoding matrix is ​​indicated by a combination of an SRS resource set indicator, a first TPMI field, a second TPMI field, and a second SRI. The first SRI may indicate the SRS resource, and the second SRI may indicate the precoding matrix type. In some aspects, the precoding matrix type may be jointly indicated by the second SRI and the SRS resource set indicator. In some aspects, the first TPMI field indicates a first rank and a first precoding matrix indicator, and the second TPMI field indicates a second precoding matrix indicator, the second rank being based on the first rank indicated in the first TPMI field, the SRS resource set indicator, and the second SRI.

[0583] In some aspects, the control signaling may further include at least one SRI, and the SRS resource set indicator may at least partially indicate the precoding matrix type, and the mapping from the 4-port uplink MIMO codebook to the 8-port precoding matrix may be indicated by at least a combination of the SRS resource set indicator, the first TPMI field, and the second TPMI field. The first TPMI field and the second TPMI field may independently indicate the first precoding matrix and the second precoding matrix. The first TPMI field may indicate the first rank and the first precoding matrix, and the second TPMI field may indicate the second rank and the second precoding matrix. The SRS resource set indicator may indicate the precoding matrix type independently of the second SRI. The SRS resource set indicator may indicate the precoding matrix type jointly with the second SRI, and the first SRI may indicate resources associated with the first precoding matrix and the second precoding matrix.

[0584] As illustrated at 5702, in some aspects, a UE may receive a configuration of a first antenna port group of four antenna ports and a second antenna port group of four antenna ports, wherein a first precoding matrix indicated by a first TPMI field is applied to the first antenna port group and a second precoding matrix indicated by a second TPMI field is applied to the second antenna port group. This reception may be performed, for example, by codebook processing component 198, transceiver 5922, and / or antenna 5980. Codebook processing component 198 may be a component of UE 104, 350, or device 5904. The control signaling may include a precoding matrix type indicator, at least one SRI indicating SRS resources used for the first and second precoding matrices, and a mapping from a 4-port uplink MIMO codebook to an 8-port precoding matrix is ​​indicated by at least the precoding matrix type indicator, the first TPMI field, and the second TPMI field. In some aspects, the control signaling may further include an additional bit indicating the precoding matrix type in conjunction with the precoding matrix type indicator, and the mapping from the 4-port uplink MIMO codebook to the 8-port precoding matrix is ​​further based on the additional bit. In some aspects, the first antenna port group and the second antenna port group are indicated to the UE in a permutation matrix.

[0585] In some aspects, the control signaling may further include a codebook subset indicator including at least one additional bit and indicating a subset from a set of codebook subsets including fully coherent transmission, partially coherent transmission, or non-coherent transmission. A first value of the codebook subset indicator may correspond to partially coherent transmission or non-coherent transmission and indicate an 8-port uplink MIMO codebook constructed based on a 4-port uplink MIMO codebook, and a second value of the codebook subset indicator may correspond to fully coherent transmission using a precoding matrix that is not based on a 4-port uplink MIMO codebook and is jointly indicated by the first TPMI field and the second TPMI field.

[0586] In some aspects, the control signaling may further include: a first SRS resource indicator (SRI) indicating an SRS resource; and a second SRI indicating a subset from a set of codebook subsets including fully coherent transmission, partially coherent transmission, or non-coherent transmission. In some aspects, the first value of the second SRI corresponds to partially coherent transmission or non-coherent transmission and indicates an 8-port uplink MIMO codebook constructed based on a 4-port uplink MIMO codebook, and the second value of the second SRI corresponds to fully coherent transmission using a precoding matrix having all non-zero entries and jointly indicated by the first TPMI field and the second TPMI field.

[0587] In some aspects, the SRS resource set indicator indicates a subset from a set of codebook subsets including fully coherent transmission, partially coherent transmission, or non-coherent transmission. In some aspects, the first three values ​​of the SRS resource set indicator correspond to partially coherent transmission or non-coherent transmission and indicate an 8-port uplink MIMO codebook constructed based on a 4-port uplink MIMO codebook, and the fourth value of the SRS resource set indicator corresponds to fully coherent transmission using a precoding matrix having all non-zero entries and indicated jointly by the first TPMI field and the second TPMI field.

[0588] In some aspects, a rank-1 8-port uplink MIMO precoder is based on a rank-1 precoding matrix and a configuration of a first antenna port group of four antenna ports and a second antenna port group of four antenna ports, wherein the 8-port uplink MIMO precoder is indicated by one of: a unit port group indicator and a single TPMI field with four states indicating a non-coherent precoder; a unit port group indicator and a single TPMI field with eight states indicating a two-antenna partially coherent precoder (PC-2); or a unit port group indicator and a single TPMI field with sixteen states indicating a four-antenna partially coherent precoder (PC-4).

[0589] In some aspects, a rank-2 8-port uplink MIMO precoder applies a rank-2 precoding matrix to a first antenna port group of four antenna ports or a second antenna port group of four antenna ports, wherein the 8-port uplink MIMO precoder is indicated by one of: a unit port group indicator and a single TPMI field with six states indicating a non-coherent precoder; or a unit port group indicator and a single TPMI field with eight states for a two-antenna partially coherent precoder (PC-2) or a four-antenna partially coherent precoder (PC-4).

[0590] In some aspects, a rank-2 8-port uplink MIMO precoder is based on a first rank-1 precoding matrix applied to a first antenna port group of four antenna ports and a second rank-1 precoding matrix applied to a second antenna port group of four antenna ports, wherein the 8-port uplink MIMO precoder is indicated by one of: a first TPMI field and a second TPMI field, each TPMI field having four states indicating a non-coherent precoder; a first TPMI field and a second TPMI field, each TPMI field having eight states indicating a two-antenna partially coherent precoder (PC-2); a first TPMI field and a second TPMI field, each TPMI field having sixteen states indicating a four-antenna partially coherent precoder (PC-4); or a single TPMI field in combination using the same precoder for both the first antenna port group and the second antenna port group.

[0591] In some aspects, a configuration of an 8-port uplink MIMO precoder of rank 2 and a first antenna port group of four antenna ports and a second antenna port group of four antenna ports, wherein the 8-port uplink MIMO precoder is indicated by one of the following: a two-bit port group indicator and a single TPMI field with six states, the states indicating a non-coherent precoder based on a single rank 2 precoding matrix applied to the first antenna port group or the second antenna port group; a two-bit port group indicator and a single TPMI field with eight states, the states indicating a two-antenna partially coherent precoder (PC-2) or a four-antenna partially coherent precoder (PC-4) based on a single rank 2 precoding matrix applied to the first antenna port group or the second antenna port group; a two-bit port group indicator, a first TPM field, and a second TPMI field. I field and the second TPMI field, each TPMI field has four states, which indicate a non-coherent predecoder based on two rank-1 precoding matrices applied to the first antenna port group or the second antenna port group; two port group indicators, the first TPMI field and the second TPMI field, each TPMI field has eight states, which indicate a two-antenna partially coherent predecoder (PC-2) based on two rank-1 precoding matrices applied to the first antenna port group or the second antenna port group; or two port group indicators, the first TPMI field and the second TPMI field, each TPMI field has sixteen states, which indicate a four-antenna partially coherent predecoder (PC-4) based on two rank-1 precoding matrices applied to the first antenna port group or the second antenna port group.

[0592] In some aspects, an 8-port uplink MIMO precoder of rank 2, wherein the rank 2 precoder is applied to a first antenna port group or a second antenna port group, or the same rank 1 precoder is applied to both the first antenna port group and the second antenna port group, the 8-port uplink MIMO precoder is indicated by one of the following: a two-bit port group indicator and a single TPMI field with 6 states, the states indicating a non-coherent precoder based on the rank 2 precoder applied to the first antenna port group or the second antenna port group; a two-bit port group indicator and a single TPMI field with 8 states, the states being for a two-antenna partially coherent precoder (PC-2) or a four-antenna partially coherent precoder with a single rank 2 precoder applied to the first antenna port group or the second antenna port group (PC-4); a two-bit port group indicator and a single TPMI field with 8 states, which indicate non-interleaved predecoder states for a two-antenna partially interleaved predecoder (PC-2) in which the same rank 1 predecoder is applied to both the first antenna port group and the second antenna port group; a two-bit port group indicator and a single TPMI field with 8 states, which are for a two-antenna partially interleaved predecoder (PC-2) in which the same rank 1 predecoder is applied to both the first antenna port group and the second antenna port group; or a two-bit port group indicator and a single TPMI field with sixteen states, which indicate a four-antenna partially interleaved predecoder (PC-4) in which the same rank 1 predecoder is applied to both the first antenna port group and the second antenna port group.

[0593] In some aspects, a configuration of an 8-port uplink MIMO precoder of rank 3 and a first antenna port group of four antenna ports and a second antenna port group of four antenna ports, wherein the 8-port uplink MIMO precoder is indicated by one of: a unit port group indicator and a single TPMI field with a single state, the state indicating a non-coherent precoder that applies a single rank 3 precoding matrix to the first antenna port group or the second antenna port group; a unit port group indicator and a single TPMI field with two states, the states being for a two-antenna partially coherent precoder (PC-2) that applies a single rank 3 precoding matrix to the first antenna port group or the second antenna port group; a unit port group indicator and a single TPMI field with four states a single TPMI field having six states and a second TPMI field having four states, these states indicating a non-coherent precoder that applies a rank 2 precoding matrix to the first antenna port group and a rank 1 precoding matrix to the second antenna port group; a first TPMI field having eight states and a second TPMI field having eight states, these states indicating a two-antenna partially phased precoder (PC-2) that applies a rank 2 precoding matrix to the first antenna port group and a rank 1 precoding matrix to the second antenna port group; a first TPMI field having eight states and a second TPMI field having eight states, these states indicating a two-antenna partially phased precoder (PC-2) that applies a rank 2 precoding matrix to the first antenna port group and a rank 1 precoding matrix to the second antenna port group; a first TPMI field having eight states and a second TPMI field having eight states, these states indicating a two-antenna partially phased precoder (PC- a first TPMI field with sixteen states and a second TPMI field with sixteen states indicating that a four-antenna partially phased precoder (PC-4) is applied to a first antenna port group and a rank-1 precoding matrix is ​​applied to a second antenna port group; a first TPMI field with four states and a second TPMI field with six states indicating that a rank-2 precoding matrix is ​​applied to a first antenna port group and a rank-1 precoding matrix is ​​applied to a non-phased precoder is applied to a second antenna port group; a first TPMI field with sixteen states and a second TPMI field with eight states indicating that a rank-2 precoding matrix is ​​applied to a first antenna port group and a rank-1 precoding matrix is ​​applied to a second antenna port group A four-antenna partially phased precoder (PC-4) for a two-antenna port group; a two-bit port group indicator and a single TPMI field with a single state indicating that a single rank-3 precoding matrix is ​​applied to a non-phased precoder for a first antenna port group or a second antenna port group; a two-bit port group indicator and a single TPMI field with two states indicating that a single rank-3 precoding matrix is ​​applied to a two-antenna partially phased precoder (PC-2) for a first antenna port group or a second antenna port group; a two-bit port group indicator and a single TPMI field with four states indicating that a single rank-3 precoding matrix is ​​applied to a four-antenna partially phased precoder (PC-4) for a first antenna port group or a second antenna port group;A two-bit port group indicator, a first TPMI field with six states, and a second TPMI field with four states, which indicate a non-coherent precoder that applies a rank-2 precoding matrix to the first antenna port group and a rank-1 precoding matrix to the second antenna port group; a two-bit port group indicator, a first TPMI field with eight states, and a second TPMI field with eight states, which indicate a two-antenna partially coherent precoder (PC-2) that applies a rank-2 precoding matrix to the first antenna port group and a rank-1 precoding matrix to the second antenna port group; a two-bit port group indicator, a first TPMI field with eight states, and a second TPMI field with sixteen states, which indicate a two-antenna partially coherent precoder (PC-2) that applies a rank-2 precoding matrix to the first antenna port group and a rank-1 precoding matrix to the second antenna port group A four-antenna partially phased precoder (PC-4) in which a code matrix is ​​applied to a first antenna port group and a rank-1 precoding matrix is ​​applied to a second antenna port group; a two-bit port group indicator, a first TPMI field having four states, and a second TPMI field having six states, which indicate that a rank-2 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to a non-phased precoder for the second antenna port group; or a two-bit port group indicator, a first TPMI field having sixteen states, and a second TPMI field having eight states, which indicate that a four-antenna partially phased precoder (PC-4) in which a rank-2 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group.

[0594] In some aspects, a rank 3 8-port uplink MIMO precoder and a configuration of a first antenna port group of four antenna ports and a second antenna port group of four antenna ports, wherein there is a relationship between a precoding matrix applied to the first antenna port group and a precoding matrix applied to the second antenna port group, wherein the 8-port uplink MIMO precoder is indicated by a two-bit port group indicator and one of the following: a single TPMI field with a single state that indicates that the rank 3 precoding matrix is ​​applied to a non-coherent precoder of the first antenna port group or the second antenna port group; a single TPMI field with two states that indicate that the rank 3 precoding matrix is ​​applied to the two antenna portions of the first antenna port group or the second antenna port group. interferometric decoder (PC-2); a single TPMI field with four states indicating a four-antenna partially interferometric decoder (PC-4) that applies a rank-3 precoding matrix to the first antenna port group or the second antenna port group; a single TPMI field with six states indicating a non-interferometric decoder that applies a rank-2 precoding matrix to the first antenna port group and a rank-1 precoding matrix to the second antenna port group; or a single TPMI field with eight states indicating a two-antenna partially interferometric decoder (PC-2) or a four-antenna partially interferometric decoder (PC-4) that applies a rank-2 precoding matrix to the first antenna port group and a rank-1 precoding matrix to the second antenna port group.

[0595] In some aspects, a configuration of an 8-port uplink MIMO precoder of rank 4 and a first antenna port group of four antenna ports and a second antenna port group of four antenna ports, wherein the 8-port uplink MIMO precoder is indicated by one of: a unit port group indicator and a single TPMI field with a single state, the state indicating a non-coherent precoder that applies a rank 4 precoding matrix to the first antenna port group or the second antenna port group; a unit port group indicator and a single TPMI field with two states, the states being for a two-antenna partially coherent precoding matrix that applies a rank 4 precoding matrix to the first antenna port group or the second antenna port group a unit port group indicator and a single TPMI field with two states for a four-antenna partially phased precoder (PC-4) that applies a rank-4 precoding matrix to the first antenna port group or the second antenna port group; a first TPMI field and a second TPMI field, each with six states, indicating that a first rank-2 precoding matrix is ​​applied to the first antenna port group and a second rank-2 precoding matrix is ​​applied to the second antenna port group; a first TPMI field and a second TPMI field, each with eight states, indicating that a first rank-2 precoding matrix is ​​applied to the first antenna port group and a second rank-2 precoding matrix is ​​applied to the second antenna port group. a two-bit port group indicator and a single TPMI field with a single state indicating that a rank-4 precoding matrix is ​​applied to a non-interrelated precoding matrix of the first antenna port group or the second antenna port group; a two-bit port group indicator and a single TPMI field with two states indicating that a rank-4 precoding matrix is ​​applied to a two-antenna partially interrelated precoding matrix (PC-2) or a four-antenna partially interrelated precoding matrix (PC-4) of the first antenna port group or the second antenna port group; A two-bit port group indicator, a first TPMI field and a second TPMI field, each having six states, which indicate a non-coherent precoder that applies a first rank-2 precoding matrix to a first antenna port group and a second rank-2 precoding matrix to a second antenna port group; or a two-bit port group indicator, a first TPMI field with eight states and a second TPMI field with eight states, which indicate a two-antenna partially coherent precoder (PC-2) or a four-antenna partially coherent precoder (PC-4) that applies a first rank-2 precoding matrix to a first antenna port group and a second rank-2 precoding matrix to a second antenna port group.

[0596] In some aspects, a rank 4 8-port uplink MIMO precoder and a configuration of a first antenna port group of four antenna ports and a second antenna port group of four antenna ports, wherein there is a relationship between a precoding matrix applied to the first antenna port group and a precoding matrix applied to the second antenna port group, wherein the 8-port uplink MIMO precoder is indicated by a two-bit port group indicator and one of the following: a single TPMI field with a single state indicating that the rank 4 precoding matrix is ​​applied to a non-coherent precoding matrix for the first antenna port group or the second antenna port group; a single TPMI field with two states indicating that the rank 4 precoding matrix is ​​applied to a two-antenna partially coherent precoding matrix for the first antenna port group or the second antenna port group a four-antenna partially phased precoder (PC-2); a single TPMI field with four states indicating a four-antenna partially phased precoder (PC-4) that applies a rank-4 precoding matrix to the first antenna port group or the second antenna port group; a single TPMI field with six states indicating a non-phased precoder that applies a first rank-2 precoding matrix to the first antenna port group and a second rank-2 precoding matrix to the second antenna port group; or a single TPMI field with eight states indicating a two-antenna partially phased precoder (PC-2) or a four-antenna partially phased precoder (PC-4) that applies a first rank-2 precoding matrix to the first antenna port group and a second rank-2 precoding matrix to the second antenna port group.

[0597] In some aspects, a rank 5 8-port uplink MIMO precoder and a configuration of a first antenna port group of four antenna ports and a second antenna port group of four antenna ports, wherein there is a relationship between a precoding matrix applied to the first antenna port group and a precoding matrix applied to the second antenna port group, wherein the 8-port uplink MIMO precoder is indicated by one of the following: a one-bit port group indicator and a single TPMI field with a single state, the state indicating that a rank 3 precoding matrix is ​​applied to the first antenna port group and a rank 2 precoding matrix is ​​applied to the second antenna port group or a rank 4 precoding matrix is ​​applied to the first antenna port group and a rank 1 precoding matrix is ​​applied to the second antenna port group; and a one-bit port group indicator. A group indicator and a single TPMI field with two states indicating a two-antenna partially phased precoder (PC-2) in which a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group, or a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group; a one-bit port group indicator and a single TPMI field with four states indicating a four-antenna partially phased precoder (PC-2) in which a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group, or a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group C-4); a one-bit port group indicator and a first TPMI field with 1 state and a second TPMI field with 1 state, the state indicating a non-coherent predecoder that applies a rank-3 precoding matrix to the first antenna port group and a rank-2 precoding matrix to the second antenna port group; a one-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 2 states, the states indicating a two-antenna partially coherent predecoder (PC-2) that applies a rank-3 precoding matrix to the first antenna port group and a rank-2 precoding matrix to the second antenna port group or that applies a rank-4 precoding matrix to the first antenna port group and a rank-1 precoding matrix to the second antenna port group; a one-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 2 states, the states indicating a two-antenna partially coherent predecoder (PC-2) that applies a rank-3 precoding matrix to the first antenna port group and a rank-2 precoding matrix to the second antenna port group; A port group indicator and a first TPMI field with 4 states and a second TPMI field with 4 states, these states indicating that a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group, or a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group. A one-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 2 states, these states indicating that a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group. A four-antenna partially phased precoder (PC-4)A one-bit port group indicator and a first TPMI field with 1 state and a second TPMI field with 6 states, which indicate that a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group; a one-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 8 states, which indicate that a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group or a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group A two-antenna partially phased precoder (PC-2) for a port group; a one-bit port group indicator and a first TPMI field with 4 states and a second TPMI field with 8 states, which indicate that a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group; a four-antenna partially phased precoder (PC-4) with a one-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 16 states, which indicate that a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group. Partially phased precoder (PC-4); a two-bit port group indicator and a single TPMI field with a single state indicating that a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group, or a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group. Non-phased precoder; a two-bit port group indicator and a single TPMI field with two states indicating that a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group, or a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group. a two-port group indicator and a single TPMI field with four states indicating that a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group; a two-port group indicator and a single TPMI field with two states indicating that a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group; a four-antenna partially phased precoder (PC-4) that applies a rank-4 precoding matrix to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group;A two-bit port group indicator and a first TPMI field with 1 state and a second TPMI field with 1 state, which states indicate that a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group, or a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group; a two-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 2 states, which states indicate that a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group. a two-antenna partially phased precoder (PC-2) or a four-antenna partially phased precoder (PC-4) that applies a rank-4 precoding matrix to the first antenna port group and a rank-1 precoding matrix to the second antenna port group; a two-bit port group indicator and a first TPMI field with 4 states and a second TPMI field with 4 states, the states indicating a four-antenna partially phased precoder (PC-4) that applies a rank-3 precoding matrix to the first antenna port group and a rank-2 precoding matrix to the second antenna port group; a two-bit port group indicator and a first TPMI field with 1 state a two-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 8 states, which indicate a two-antenna partially correlated precoder (PC-2) that applies a rank-3 precoding matrix to the first antenna port group and a rank-2 precoding matrix to the second antenna port group; a two-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 8 states, which indicate a two-antenna partially correlated precoder (PC-2) that applies a rank-3 precoding matrix to the first antenna port group and a rank-2 precoding matrix to the second antenna port group or a rank-4 precoding matrix to the first antenna port group and a rank-1 precoding matrix to the second antenna port group ); a two-bit port group indicator and a first TPMI field with 4 states and a second TPMI field with 8 states, which indicate a four-antenna partially phased precoder (PC-4) in which a rank-3 precoding matrix is ​​applied to the first antenna port group and a rank-2 precoding matrix is ​​applied to the second antenna port group; or a two-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 16 states, which indicate a four-antenna partially phased precoder (PC-4) in which a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-1 precoding matrix is ​​applied to the second antenna port group. ;

[0598] In some aspects, the 8-port uplink MIMO precoder is of rank 6, and there is a relationship between a first precoding matrix applied to a first antenna port group and a second precoding matrix applied to a second antenna port group, wherein the 8-port uplink MIMO precoder is indicated by one of the following: a single TPMI field having a single state indicating that a first rank 3 precoding matrix is ​​applied to the first antenna port group and a second rank 3 precoding matrix is ​​applied to the second antenna port group; a single TPMI field having two states indicating that a first rank 3 precoding matrix is ​​applied to the first antenna port group and a second rank 3 precoding matrix is ​​applied to the second antenna port group. A two-antenna partially phased precoder (PC-2) with a two-antenna port group or a rank-4 precoding matrix applied to the first antenna port group and a rank-2 precoding matrix applied to the second antenna port group; a single TPMI field with four states indicating that a first rank-3 precoding matrix is ​​applied to the first antenna port group and a second rank-3 precoding matrix is ​​applied to the second antenna port group or a four-antenna partially phased precoder (PC-4) with a rank-4 precoding matrix applied to the first antenna port group and a rank-2 precoding matrix applied to the second antenna port group; a one-bit port group indicator and a first TPMI field with 1 state and a second TPMI field with 1 state fields, these states indicating that a rank-4 precoding matrix is ​​applied to a first antenna port group and a rank-2 precoding matrix is ​​applied to a non-coherent precoding matrix for a second antenna port group; a one-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 2 states, these states indicating that a rank-4 precoding matrix is ​​applied to a first antenna port group and a rank-2 precoding matrix is ​​applied to a two-antenna partially coherent precoding matrix (PC-2) for a second antenna port group; a one-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 2 states, these states indicating that a rank-4 precoding matrix is ​​applied to a first antenna port group and a four-antenna partially phased precoder (PC-4) in which a rank-1 precoding matrix is ​​applied to a second antenna port group; a first TPMI field having 1 state and a second TPMI field having 1 state, these states indicating that a first rank-3 precoding matrix is ​​applied to the first antenna port group and a second rank-3 precoding matrix is ​​applied to a non-phased precoder of the second antenna port group; a first TPMI field having 2 states and a second TPMI field having 2 states, these states indicating that a first rank-3 precoding matrix is ​​applied to the first antenna port group and a second rank-3 precoding matrix is ​​applied to a two-antenna partially phased precoder (PC-2) of the second antenna port group;A first TPMI field with 4 states and a second TPMI field with 4 states, which states indicate that a first rank 3 precoding matrix is ​​applied to the first antenna port group and a second rank 3 precoding matrix is ​​applied to a four-antenna partially phased precoder (PC-4) for the second antenna port group; a first TPMI field with 1 state and a second TPMI field with 6 states, which states indicate that a rank 4 precoding matrix is ​​applied to the first antenna port group and a rank 2 precoding matrix is ​​applied to a non-phased precoder for the second antenna port group; a first TPMI field with 2 states and a second TPMI field with 8 states, which states indicate that a rank 4 precoding matrix is ​​applied to the first antenna port group and a rank 2 precoding matrix is ​​applied to the non-phased precoder for the second antenna port group A two-antenna partially phased precoder (PC-2) for a first antenna port group and applying a rank-2 precoding matrix to a second antenna port group; a four-antenna partially phased precoder (PC-4) for a first antenna port group and applying a rank-2 precoding matrix to a second antenna port group; a two-bit port group indicator and a single TPMI field with a single state indicating either applying a first rank-3 precoding matrix to the first antenna port group and a second rank-3 precoding matrix to the second antenna port group or applying a rank-4 precoding matrix to the first antenna port group. A two-antenna partially phased precoder (PC-2) that applies a first rank 3 precoding matrix to the first antenna port group and a second rank 3 precoding matrix to the second antenna port group; a two-bit port group indicator and a single TPMI field with two states that indicate either applying a first rank 3 precoding matrix to the first antenna port group and a second rank 3 precoding matrix to the second antenna port group or applying a rank 4 precoding matrix to the first antenna port group and a rank 2 precoding matrix to the second antenna port group; a two-bit port group indicator and a single TPMI field with four states that indicate applying a first rank 3 precoding matrix to the first antenna port group and a second rank 3 precoding matrix to the second antenna port group antenna port group; a two-bit port group indicator and a single TPMI field with two states, the states indicating a four-antenna partially phased precoder (PC-4) that applies a rank-4 precoding matrix to a first antenna port group and a rank-2 precoding matrix to a second antenna port group; a two-bit port group indicator and a first TPMI field with 1 state and a second TPMI field with 1 state, the states indicating a non-phased precoder that applies a first rank-3 precoding matrix to the first antenna port group and a second rank-3 precoding matrix to the second antenna port group or that applies a rank-4 precoding matrix to the first antenna port group and a rank-2 precoding matrix to the second antenna port group;A two-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 2 states, these states indicating that a first rank 3 precoding matrix is ​​applied to the first antenna port group and a second rank 4 precoding matrix is ​​applied to the second antenna port group, or a rank 4 precoding matrix is ​​applied to the first antenna port group and a rank 2 precoding matrix is ​​applied to the second antenna port group for a two-antenna partially phased precoder (PC-2) or a four-antenna partially phased precoder (PC-4); a two-bit port group indicator and a first TPMI field with 4 states and a second TPMI field with 4 states, these states indicating that a first rank 3 precoding matrix is ​​applied to the first antenna port group and a second rank 3 precoding matrix is ​​applied to the second antenna port group A four-antenna partially phased precoder (PC-4) with a rank-4 precoding matrix applied to the first antenna port group and a rank-2 precoding matrix applied to the second antenna port group; a two-bit port group indicator and a first TPMI field with 1 state and a second TPMI field with 6 states, these states indicating a non-phased precoder that applies a rank-4 precoding matrix to the first antenna port group and a rank-2 precoding matrix to the second antenna port group; or a two-bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 8 states, these states indicating a two-antenna partially phased precoder (PC-2) or a four-antenna partially phased precoder (PC-4) with a rank-4 precoding matrix applied to the first antenna port group and a rank-2 precoding matrix applied to the second antenna port group.

[0599] In some aspects, the 8-port uplink MIMO precoder is of rank 7, and there is a relationship between a first precoding matrix applied to a first antenna port group and a second precoding matrix applied to a second antenna port group, wherein the 8-port uplink MIMO precoder is indicated by one of the following: a single TPMI field having a single state indicating that a rank 4 precoding matrix is ​​applied to the first antenna port group and a second rank 3 precoding matrix is ​​applied to the second antenna port group; a single TPMI field having two states indicating that a rank 4 precoding matrix is ​​applied to the first antenna port group and a second rank 3 precoding matrix is ​​applied to the second antenna port group. a two-antenna partially phased precoder (PC-2) or a four-antenna partially phased precoder (PC-4) with a rank-3 precoding matrix applied to the second antenna port group; a first TPMI field with 1 state and a second TPMI field with 1 state, these states indicating that a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-3 precoding matrix is ​​applied to a non-phased precoder for the second antenna port group; a first TPMI field with 2 states and a second TPMI field with 2 states, these states indicating that a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-3 precoding matrix is ​​applied to the second antenna port group a two-antenna partially phased precoder (PC-2) for a first antenna port group; a four-antenna partially phased precoder (PC-4) with a first TPMI field having 4 states and a second TPMI field having 4 states, the states indicating that a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-3 precoding matrix is ​​applied to the second antenna port group; a one-bit port group indicator and a first TPMI field having 1 state and a second TPMI field having 1 state, the states indicating that a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-3 precoding matrix is ​​applied to the second antenna port group; a one-bit port group indicator and a first TPMI field having 1 state and a second TPMI field having 1 state, the states indicating that a non-phased precoder with a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-3 precoding matrix is ​​applied to the second antenna port group; A bit port group indicator and a first TPMI field with 2 states and a second TPMI field with 2 states, which indicate a two-antenna partially phased precoder (PC-2) in which a rank-4 precoding matrix is ​​applied to the first antenna port group and a second rank-3 precoding matrix is ​​applied to the second antenna port group; or a bit port group indicator and a first TPMI field with 4 states and a second TPMI field with 4 states, which indicate a four-antenna partially phased precoder (PC-4) in which a rank-4 precoding matrix is ​​applied to the first antenna port group and a rank-3 precoding matrix is ​​applied to the second antenna port group.In some aspects, the 8-port uplink MIMO precoder is of rank 8, and there is a relationship between a first precoding matrix applied to a first antenna port group and a second precoding matrix applied to a second antenna port group, wherein the 8-port uplink MIMO precoder is indicated by one of the following: a single TPMI field with 1 state, the state indicating a non-coherent precoding matrix that applies a first rank 4 precoding matrix to the first antenna port group and a second rank 4 precoding matrix to the second antenna port group; a single TPMI field with two states, the states indicating a two-antenna partially coherent precoding matrix (PC-2) or a four-antenna partially coherent precoding matrix (PC-4) that applies a first rank 4 precoding matrix to the first antenna port group and a second rank 4 precoding matrix to the second antenna port group; a first TPMI field with 1 state A TPMI field and a second TPMI field with 1 state, these states indicating a non-coherent precoder that applies a first rank-4 precoding matrix to a first antenna port group and a second rank-4 precoding matrix to a second antenna port group; a first TPMI field with 2 states and a second TPMI field with 2 states, these states indicating a two-antenna partially coherent precoder (PC-2) that applies the first rank-4 precoding matrix to the first antenna port group and the second rank-4 precoding matrix to the second antenna port group; or a first TPMI field with 2 states and a second TPMI field with 2 states, these states indicating a four-antenna partially coherent precoder (PC-4) that applies the first rank-4 precoding matrix to the first antenna port group and the second rank-4 precoding matrix to the second antenna port group.

[0600] Figure 58A 5800 is a flow chart of a method of wireless communication. The method may be performed by a UE (eg, UE 104, 350; device 5904). The method may enable the UE to transmit UL MIMO transmissions using various precoding options for 8Tx.

[0601] At 5806, the UE receives control signaling for UL transmission. This reception may be performed, for example, by the codebook processing component 198, the transceiver 5922, and / or the antenna 5980. The codebook processing component 198 may be a component of the UE 104, 350, or the apparatus 5904.

[0602] At 5812, the UE transmits an UL MIMO transmission precoded with an 8-port uplink MIMO precoder based on the control signaling and the set of two or more antenna port groups. The transmission may be performed, for example, by the codebook processing component 198, the transceiver 5922, and / or the antenna 5980. The codebook processing component 198 may be a component of the UE 104, 350, or the device 5904.

[0603] In some aspects, the precoder may provide a single precoder for each of rank 5, rank 6, rank 7, or rank 8 of the 8-port uplink MIMO precoder based on the rank of the UL MIMO transmission. In some aspects, the 8-port uplink MIMO precoder may be based on a discrete Fourier transform (DFT) codebook with an oversampling factor of 2 and a common phase. In some aspects, 8 precoders may be provided for each of rank 5 and rank 6, and 4 precoders may be provided for each of rank 7 and rank 8. In some aspects, 8 precoders may be provided for each of rank 5, rank 6, rank 7, and rank 8. In some aspects, the 8-port uplink MIMO precoder may be based on a codebook optimized for spatially uncorrelated channels. In some aspects, the codebook may be based on a combination of two 4×4 Householder matrices, and wherein a common phase is applied between two antenna port groups. In some aspects, an 8-port uplink MIMO precoder may be based on an 8Tx precoder based on a precoder co-phasing used for fewer than 8 antenna ports. In some aspects, a subset of the 8Tx precoder may be used depending on the rank of the UL MIMO transmission. In some aspects, multiple layers may be transmitted using one or more groups of coherent antenna ports. In some aspects, one or more groups of coherent antenna ports may include a first subset of four coherent antenna ports and a second subset of four coherent antenna ports. In some aspects, one or more groups of coherent antenna ports may include a first subset of two coherent antenna ports, a second subset of two coherent antenna ports, and a third subset of four coherent antenna ports. In some aspects, one or more groups of coherent antenna ports may include a first subset of two coherent antenna ports, a second subset of two coherent antenna ports, a third subset of two coherent antenna ports, and a fourth subset of two coherent antenna ports. In some aspects, the UL MIMO transmission may be a combination of partially coherent transmission and non-coh...

Claims

1. An apparatus for wireless communication at a user equipment (UE), the apparatus comprising: Memory; and at least one processor coupled to the memory and based at least in part on the information stored in the memory, the at least one processor configured to: receiving control signaling for uplink (UL) multiple-input multiple-output (MIMO) transmission; and The UL MIMO transmission precoded with an 8-port uplink MIMO precoder is transmitted based on the control signaling and a set of two or more antenna port groups.

2. The apparatus of claim 1, wherein the precoder provides a single precoder for each of rank 5, rank 6, rank 7, or rank 8 of the 8-port uplink MIMO precoder based on the rank of the UL MIMO transmission.

3. The apparatus of claim 2, wherein based at least in part on the information stored in the memory, the at least one processor is further configured to: An indication is received to select four antenna ports from a set of eight antenna ports according to the rank for the UL MIMO transmission and to select one or more additional antenna ports having a lowest port index from four unindicated antenna ports in the set of eight antenna ports.

4. The apparatus of claim 2, wherein based at least in part on the information stored in the memory, the at least one processor is further configured to: receiving an indication of a first set of four antenna ports from a set of eight antenna ports and a second set of four antenna ports from the set of eight antenna ports, wherein the UE applies the eight-port uplink MIMO precoder to the first set of four antenna ports and one or more additional antenna ports from the second set of four antenna ports according to the rank for the UL MIMO transmission, the one or more additional antenna ports from the second set of four antenna ports being applied in a set order indicated by the second set of four antenna ports.

5. The apparatus according to claim 1, wherein two predecoders are provided for rank 5, rank 6, rank 7 or rank 8 of the 8-port uplink MIMO predecoder, and the two predecoders are applied to one or more sets of coherent antenna port pairs of a set of 8 antenna ports, and the apparatus also includes applying coherent combining for each coherent antenna port pair.

6. The apparatus of claim 5, wherein based at least in part on the information stored in the memory, the at least one processor is further configured to: An indication is received to select two sets of coherent antenna port pairs from the set of eight antenna ports according to a rank for the UL MIMO transmission and to select one or more additional antenna ports, the one or more additional antenna ports being selected from the remaining coherent antenna port pairs.

7. The apparatus of claim 5, wherein based at least in part on the information stored in the memory, the at least one processor is further configured to: receiving an indication of a first set of two coherent antenna port pairs from the set of eight antenna ports and a second set of two coherent antenna port pairs, wherein the UE applies the eight-port uplink MIMO precoder to the first set of two coherent antenna port pairs and one or more additional antenna ports from the second set of two coherent antenna port pairs according to a rank for the UL MIMO transmission, the one or more additional antenna ports from the second set of two antenna ports being applied in a set order indicated by the second set of two coherent antenna port pairs.

8. The apparatus of claim 1 , wherein two predecoders are provided for rank 5, rank 6, rank 7, or rank 8 of the 8-port uplink MIMO predecoder, the two predecoders being applied to a first group of four coherent antenna ports and a second group of four coherent antenna ports, wherein based at least in part on the information stored in the memory, the at least one processor is further configured to: Coherent combining is applied using an orthogonal sequence of length 4 for each coherent antenna port group, where there is one of the following: A first set of layers is based on the first set of four coherent antenna ports and a second set of layers is based on the second set of four coherent antenna ports according to a rank of the 8-port uplink MIMO transmission, or According to the rank of the 8-port uplink MIMO transmission, the first four layers of the UL MIMO transmission are based on the first set of four coherent antenna ports and additional one or more layers are based on the second set of four coherent antenna ports.

9. The apparatus of claim 1, wherein the 8-port uplink MIMO pre-coder is based on a discrete Fourier transform (DFT) codebook with an oversampling factor of 2 and with a common phase.

10. The apparatus of claim 9, wherein 8 pre-decoders are provided for each of rank 5 and rank 6, and 4 pre-decoders are provided for each of rank 7 and rank 8.

11. The apparatus of claim 9, wherein 8 precoders are provided for each of rank 5, rank 6, rank 7, and rank 8.

12. The apparatus of claim 1, wherein the 8-port uplink MIMO precoder is based on a codebook optimized for spatially uncorrelated channels.

13. The apparatus of claim 12, wherein the codebook is based on a combination of two 4x4 Householder matrices, and wherein co-phasing is applied between two antenna port groups.

14. The apparatus of claim 1, wherein the 8-port uplink MIMO precoder is based on an 8Tx precoder based on precoder co-phasing used for less than 8 antenna ports.

15. The apparatus of claim 14, wherein a subset of the 8Tx precoders is used according to a rank of the UL MIMO transmission.

16. The apparatus of claim 1, wherein the plurality of layers are transmitted using one or more sets of coherent antenna ports.

17. The apparatus of claim 16, wherein the one or more groups of coherent antenna ports include a first subset of four coherent antenna ports and a second subset of four coherent antenna ports.

18. The apparatus of claim 16, wherein the one or more groups of coherent antenna ports include a first subset of two coherent antenna ports, a second subset of two coherent antenna ports, and a third subset of four coherent antenna ports.

19. The apparatus of claim 16, wherein the one or more groups of coherent antenna ports include a first subset of two coherent antenna ports, a second subset of two coherent antenna ports, a third subset of two coherent antenna ports, and a fourth subset of two coherent antenna ports.

20. The apparatus of claim 16, wherein the UL MIMO transmission is a combination of partially coherent transmission and non-coherent transmission, and wherein the one or more groups of coherent antenna ports include a first subset of one antenna port, a second subset of one antenna port, a third subset of two coherent antenna ports, and a fourth subset of four coherent antenna ports.

21. The apparatus of claim 1 , wherein based at least in part on the information stored in the memory, the at least one processor is further configured to: receiving an indication of an active antenna port group; and A TPMI and a rank indicator are received for the set of active antenna ports.

22. The apparatus of claim 21, wherein the number of bits in the TPMI field for the 8-port UL MIMO transmission is reduced compared to a 4-port UL MIMO transmission.

23. The apparatus of claim 1 , wherein the precoder for each antenna port group is based on a codebook for 2-port UL MIMO transmission or 4-port UL MIMO transmission, wherein based at least in part on the information stored in the memory, the at least one processor is further configured to: The scaling factor is applied based on the number of antenna ports in the corresponding antenna port group to which the precoder is applied.

24. The apparatus of claim 1, wherein based at least in part on the information stored in the memory, the at least one processor is further configured to: An indication is sent that a coherence assumption for the antenna port group is supported.

25. The apparatus of claim 1, wherein antenna ports from different antenna port groups are configured in a single sounding reference signal (SRS) resource, each antenna port group having at least one of a different cyclic shift or a different comb index.

26. The apparatus of claim 1, wherein antenna ports from different antenna port groups are configured with different sounding reference signal (SRS) resources.

27. An apparatus for wireless communication at a network node, the apparatus comprising: Memory; and at least one processor coupled to the memory and based at least in part on the information stored in the memory, the at least one processor configured to: outputting control signaling for uplink (UL) multiple-input multiple-output (MIMO) transmission for transmission; and The UL MIMO transmission precoded with an 8-port uplink MIMO precoder is obtained based on the control signaling and a set of two or more antenna port groups.

28. The apparatus of claim 27, wherein the predecoder provides a single predecoder for each of rank 5, rank 6, rank 7, or rank 8 of the 8-port uplink MIMO predecoder based on a rank of the UL MIMO transmission, and based at least in part on the information stored in the memory, the at least one processor is further configured to: outputting an indication of selecting four antenna ports from a set of eight antenna ports and selecting one or more additional antenna ports for transmission according to the rank for the UL MIMO transmission, the one or more additional antenna ports having the lowest port index from the four unindicated antenna ports in the set of eight antenna ports, or and outputting an indication of a first set of four antenna ports from a set of eight antenna ports and a second set of four antenna ports from the set of eight antenna ports for transmission, wherein the UE applies the 8-port uplink MIMO precoder to the first set of four antenna ports and one or more additional antenna ports from the second set of four antenna ports according to the rank for the UL MIMO transmission, the one or more additional antenna ports from the second set of four antenna ports being applied in a set order indicating the second set of four antenna ports.

29. The apparatus of claim 27, wherein based at least in part on the information stored in the memory, the at least one processor is further configured to: outputting an indication of the set of active antenna ports for transmission; and The TPMI and rank indicator for the active antenna port group are output for transmission.

Images