WO2021212468A1

WO2021212468A1 - System and method for uplink multiple-input multiple-output transmission

Info

Publication number: WO2021212468A1
Application number: PCT/CN2020/086676
Authority: WO
Inventors: Fang Yuan; Wooseok Nam; Tao Luo
Original assignee: Qualcomm Incorporated
Priority date: 2020-04-24
Filing date: 2020-04-24
Publication date: 2021-10-28

Abstract

A first apparatus may be configured to receive, from a base station, DCI associated with configuring uplink transmission by the UE on an uplink data channel. The first apparatus may determine at least one layer mapping pattern based on the DCI. The first apparatus may then transmit at least two repetitions of each coded part of the uplink transmission on the uplink data channel to the base station based on the at least one layer mapping pattern. A second apparatus may be configured to determine at least one layer mapping pattern associated with uplink transmission by a UE. The second apparatus may transmit, to the UE, DCI configuring the uplink transmission by the UE. Subsequently, the second apparatus may receive, from the UE, at least two repetitions of each coded part of the uplink transmission on an uplink data channel based on the at least one layer mapping pattern.

Description

SYSTEM AND METHOD FOR UPLINK MULTIPLE-INPUT MULTIPLE-OUTPUT TRANSMISSION

BACKGROUND

Technical Field

The present disclosure relates generally to communication systems, and more particularly, to a user equipment configured to transmit coded bits mapped to layers.

Introduction

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources. 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.

These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. An example telecommunication standard is 5G New Radio (NR) . 5G NR is part of a continuous mobile broadband evolution promulgated by Third Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with 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) . Some aspects of 5G NR may be based on the 4G Long Term Evolution (LTE) standard. There exists a need for further improvements in 5G NR technology. These improvements may also be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.

SUMMARY

The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor 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 is presented later.

In an example radio access technology (RAT) , a base station may schedule uplink data transmission by a user equipment (UE) using downlink control information (DCI) . The base station may transmit a DCI message in order to schedule uplink transmission on an uplink data channel by the UE. The UE may transmit the uplink transmission as multiple coded bit parts on the uplink channel based on the DCI message. In particular, the UE may transmit each coded bit part via a respective layer set and, in some aspects, each layer set may correspond to an antenna panel with a beam of the UE.

For uplink transmission on the uplink data channel, the UE may map the coded bit parts to resources. For example, the UE may map the coded bit parts to a layer first, to frequency resources second, and then to time resources third. In some aspects, resource mapping to the uplink data channel may be based on the port index order of demodulation reference signals (DMRSs) . Such resource mapping based on DMRS port order may be suitable for uplink transmissions by some UEs that each have a single panel.

However, some other UEs may each include multiple panels for uplink transmissions. The diversity gain associated with communication by a UE may be improved through use of the multiple panels. Thus, a need exists for approaches to multi-panel uplink transmissions by UEs. The present disclosure describes various techniques and solutions to multi-panel uplink transmission by a UE through layer sweeping, which may improve diversity gain in wireless communication. For example, the present disclosure provides for configuring UEs with layer mapping patterns, and transmitting multiple coded parts of uplink transmissions based on layer mapping patterns.

In a first aspect of the disclosure, a first method, a first computer-readable medium, and a first apparatus are provided. The first apparatus may be a UE. The first apparatus may be configured to receive, from a base station, DCI associated with configuring uplink transmission by the UE on an uplink data channel. The first apparatus may determine at least one layer mapping pattern based on the DCI. The first apparatus may then transmit at least two repetitions of each coded part of the uplink transmission on the uplink data channel to the base station based on the at least one layer mapping pattern.

In a second aspect of the disclosure, a second method, a second computer-readable medium, and a second apparatus are provided. The second apparatus may be a base station. The second apparatus may be configured to determine at least one layer mapping pattern associated with uplink transmission by a UE. The second apparatus may transmit, to the UE, DCI configuring the uplink transmission by the UE. Subsequently, the second apparatus may receive, from the UE, at least two repetitions of each coded part of the uplink transmission on an uplink data channel based on the at least one layer mapping pattern.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed, and this description is intended to include all such aspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating an example of a wireless communications system and an access network.

FIGs. 2A, 2B, 2C, and 2D are diagrams illustrating examples of a first 5G/NR frame, DL channels within a 5G/NR subframe, a second 5G/NR frame, and UL channels within a 5G/NR subframe, respectively.

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

FIG. 4 is a diagram illustrating an example of multi-panel uplink transmission scheduled by downlink control information (DCI) in a wireless communications system.

FIG. 5 is a call flow diagram illustrating example operations associated with multi-panel uplink transmission by a UE to a base station in a wireless communications system.

FIG. 6 is a diagram illustrating an example of multi-panel uplink transmission based on at least one layer mapping pattern in a wireless communications system.

FIG. 7 is a diagram illustrating another example of multi-panel uplink transmission based on at least one layer mapping pattern in a wireless communications system.

FIG. 8 is a diagram illustrating a further example of multi-panel uplink transmission based on at least one layer mapping pattern in a wireless communications system.

FIG. 9 is a flowchart of an example method of wireless communication by a UE.

FIG. 10 is a flowchart of an example method of wireless communication by a base station.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

Several aspects of telecommunication systems will now be presented with reference to various apparatus and methods. These apparatus and methods will be 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 may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

By way of example, an element, or any portion of an element, or any combination of elements may be implemented as a “processing system” that 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 a chip (SoC) , baseband processors, field programmable gate arrays (FPGAs) , programmable logic devices (PLDs) , state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described throughout this disclosure. One or more processors in the processing system may execute software. Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

Accordingly, in one or more example embodiments, the functions described may be implemented in hardware, software, or any combination thereof. If implemented in software, the functions may be stored on or encoded as one or more instructions or code on a computer-readable medium. Computer-readable media includes computer storage media. Storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise a random-access memory (RAM) , a read-only memory (ROM) , an electrically erasable programmable ROM (EEPROM) , optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of the aforementioned 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.

FIG. 1 is a diagram illustrating an example of a wireless communications system and an access network 100. The wireless communications system (also referred to as a wireless wide area network (WWAN) ) includes base stations 102, user equipment (UE) 104, an Evolved Packet Core (EPC) 160, and another core network 190 (e.g., a 5G Core (5GC) ) . The base stations 102 may include macrocells (high power cellular base station) and/or small cells (low power cellular base station) . The macrocells include base stations. The small cells include femtocells, picocells, and microcells.

The base stations 102 configured for 4G Long Term Evolution (LTE) (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN) ) may interface with the EPC 160 through first backhaul links 132 (e.g., S1 interface) . The base stations 102 configured for 5G New Radio (NR) (collectively referred to as Next Generation RAN (NG-RAN) ) may interface with core network 190 through second backhaul links 184. In addition to other functions, the base stations 102 may perform one or more of the following functions: transfer of user data, radio channel ciphering and deciphering, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity) , inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS) , subscriber and equipment trace, RAN information management (RIM) , paging, positioning, and delivery of warning messages. The base stations 102 may communicate directly or indirectly (e.g., through the EPC 160 or core network 190) with each other over third backhaul links 134 (e.g., X2 interface) . The third backhaul links 134 may be wired or wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Each of the base stations 102 may provide communication coverage for a respective geographic coverage area 110. There may be overlapping geographic coverage areas 110. For example, the small cell 102' may have a coverage area 110' that overlaps the coverage area 110 of one or more macro base stations 102. A network that includes both small cell and macrocells may be known as a heterogeneous network. A heterogeneous network may also include Home Evolved Node Bs (eNBs) (HeNBs) , which may provide service to a restricted group known as a closed subscriber group (CSG) . The communication links 120 between the base stations 102 and the UEs 104 may include uplink (UL) (also referred to as reverse link) transmissions from a UE 104 to a base station 102 and/or downlink (DL) (also referred to as forward link) transmissions from a base station 102 to a UE 104. The communication links 120 may use multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and/or transmit diversity. The communication links may be through one or more carriers. The base stations 102 /UEs 104 may use spectrum up to Y MHz (e.g., 5, 10, 15, 20, 100, 400, etc. MHz) bandwidth per carrier allocated in a carrier aggregation of up to a total of Yx MHz (x component carriers) used for transmission in each direction. The carriers may or may not be adjacent to each other. Allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL than for UL) . The component carriers may include a primary component carrier and one or more secondary component carriers. A primary component carrier may be referred to as a primary cell (PCell) and a secondary component carrier may be referred to as a secondary cell (SCell) .

Certain UEs 104 may communicate with each other using device-to-device (D2D) communication link 158. The D2D communication link 158 may use the DL/UL WWAN spectrum. The 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 through a variety of wireless D2D communications systems, such as for example, FlashLinQ, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the IEEE 802.11 standard, LTE, or NR.

The wireless communications system may further include a Wi-Fi access point (AP) 150 in communication with Wi-Fi stations (STAs) 152 via communication links 154 in a 5 GHz unlicensed frequency spectrum. When communicating in an unlicensed frequency spectrum, the STAs 152 /AP 150 may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.

The small cell 102' may operate in a licensed and/or an unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell 102' may employ NR and use the same 5 GHz unlicensed frequency spectrum as used by the Wi-Fi AP 150. The small cell 102', employing NR in an unlicensed frequency spectrum, may boost coverage to and/or increase capacity of the access network.

A base station 102, whether a small cell 102' or a large cell (e.g., macro base station) , may include and/or be referred to as an eNB, gNodeB (gNB) , or another type of base station. Some base stations, such as gNB 180 may operate in a traditional sub 6 GHz spectrum, in millimeter wave (mmW) frequencies, and/or near mmW frequencies in communication with the UE 104. When the gNB 180 operates in mmW or near mmW frequencies, the gNB 180 may be referred to as an mmW base station. Extremely high frequency (EHF) is part of the RF in the electromagnetic spectrum. EHF has a range of 30 GHz to 300 GHz and a wavelength between 1 millimeter and 10 millimeters. Radio waves in the band may be referred to as a millimeter wave. Near mmW may extend down to a frequency of 3 GHz with a wavelength of 100 millimeters. The super high frequency (SHF) band extends between 3 GHz and 30 GHz, also referred to as centimeter wave. Communications using the mmW /near mmW radio frequency band (e.g., 3 GHz –300 GHz) has extremely high path loss and a short range. The mmW base station 180 may utilize beamforming 182 with the UE 104 to compensate for the extremely high path loss and short range. The base station 180 and the UE 104 may each include a plurality of antennas, such as antenna elements, antenna panels, and/or antenna arrays to facilitate the beamforming.

The base station 180 may transmit a beamformed signal to the UE 104 in one or more transmit directions 182'. The UE 104 may receive the beamformed signal from the base station 180 in one or more receive directions 182” . The UE 104 may also transmit a beamformed signal to the base station 180 in one or more transmit directions. The base station 180 may receive the beamformed signal from the UE 104 in one or more receive directions. The base station 180 /UE 104 may perform beam training to determine the best receive and transmit directions for each of the base station 180 /UE 104. The transmit and receive directions for the base station 180 may or may not be the same. The transmit and receive directions for the UE 104 may or may not be the same.

The EPC 160 may include a Mobility Management Entity (MME) 162, other MMEs 164, a Serving Gateway 166, a Multimedia Broadcast Multicast Service (MBMS) Gateway 168, a Broadcast Multicast Service Center (BM-SC) 170, and a Packet Data Network (PDN) Gateway 172. The MME 162 may be in communication with a Home Subscriber Server (HSS) 174. The MME 162 is the control node that processes the signaling between the UEs 104 and the EPC 160. Generally, the MME 162 provides bearer and connection management. All user Internet protocol (IP) packets are transferred through the Serving Gateway 166, which itself is connected to the PDN Gateway 172. The PDN Gateway 172 provides UE IP address allocation as well as other functions. The PDN Gateway 172 and the BM-SC 170 are connected to the IP Services 176. The IP Services 176 may include the Internet, an intranet, an IP Multimedia Subsystem (IMS) , a PS Streaming Service, and/or other IP services. The BM-SC 170 may provide functions for MBMS user service provisioning and delivery. The BM-SC 170 may serve as an entry point for content provider MBMS transmission, may be used to authorize and initiate MBMS Bearer Services within a public land mobile network (PLMN) , and may be used to schedule MBMS transmissions. The MBMS Gateway 168 may be used to distribute MBMS traffic to the base stations 102 belonging to a Multicast Broadcast Single Frequency Network (MBSFN) area broadcasting a particular service, and may be responsible for session management (start/stop) and for collecting eMBMS related charging information.

The core network 190 may include a Access and Mobility Management Function (AMF) 192, other AMFs 193, a Session Management Function (SMF) 194, and a User Plane Function (UPF) 195. The AMF 192 may be in communication with a Unified Data Management (UDM) 196. The AMF 192 is the control node that processes the signaling between the UEs 104 and the core network 190. Generally, the AMF 192 provides QoS flow and session management. All user Internet protocol (IP) packets are transferred through the UPF 195. The UPF 195 provides UE IP address allocation as well as other functions. The UPF 195 is connected to the IP Services 197. The IP Services 197 may include the Internet, an intranet, an IP Multimedia Subsystem (IMS) , a PS Streaming Service, and/or other IP services.

The base station may include and/or be referred to as a gNB, Node B, 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 reception point (TRP) , or some other suitable terminology. The base station 102 provides an access point to the EPC 160 or core network 190 for a UE 104. Examples of UEs 104 include a cellular phone, a smart phone, a session initiation protocol (SIP) phone, a laptop, a personal digital assistant (PDA) , a satellite radio, a global positioning system, a multimedia device, a video device, a digital audio player (e.g., MP3 player) , a camera, a game console, a tablet, a smart device, a wearable device, a vehicle, an electric meter, a gas pump, a large or small kitchen appliance, a healthcare device, an implant, a sensor/actuator, a display, or any other similar functioning device. Some of the UEs 104 may be referred to as IoT devices (e.g., parking meter, gas pump, toaster, vehicles, heart monitor, etc. ) . The UE 104 may also be referred to as a station, a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology.

Although the present disclosure may focus on 5G NR, the concepts and various aspects described herein may be applicable to other similar areas, such as LTE, LTE-Advanced (LTE-A) , Code Division Multiple Access (CDMA) , Global System for Mobile communications (GSM) , or other wireless/radio access technologies.

Referring again to FIG. 1, in certain aspects, the UE 104 may be configured to receive, from the base station 102/180, downlink control information (DCI) associated with configuring uplink transmission by the UE 104 on an uplink data channel. The UE 104 may determine at least one layer mapping pattern based on the DCI. The UE 104 may then transmit at least two repetitions of each coded part of the uplink transmission on the uplink data channel to the base station 102/180 based on the at least one layer mapping pattern (198) .

Correspondingly, the base station 102/180 may be configured to determine at least one layer mapping pattern associated with uplink transmission by the UE 104. The base station 102/180 may transmit, to the UE 104, the DCI configuring the uplink transmission by the UE 104. Subsequently, the base station 102/180 may receive, from the UE 104, the at least two repetitions of each coded part of the uplink transmission on an uplink data channel based on the at least one layer mapping pattern (198) .

FIG. 2A is a diagram 200 illustrating an example of a first subframe within a 5G/NR frame structure. FIG. 2B is a diagram 230 illustrating an example of DL channels within a 5G/NR subframe. FIG. 2C is a diagram 250 illustrating an example of a second subframe within a 5G/NR frame structure. FIG. 2D is a diagram 280 illustrating an example of UL channels within a 5G/NR subframe. The 5G/NR frame structure may be FDD in which for a particular set of subcarriers (carrier system bandwidth) , subframes within the set of subcarriers are dedicated for either DL or UL, or may be TDD in which for a particular set of subcarriers (carrier system bandwidth) , subframes within the set of subcarriers are dedicated for both DL and UL. In the examples provided by FIGs. 2A, 2C, the 5G/NR frame structure is assumed to be TDD, with subframe 4 being configured with slot format 28 (with mostly DL) , where D is DL, U is UL, and X is flexible for use between DL/UL, and subframe 3 being configured with slot format 34 (with mostly UL) . While

subframes

3, 4 are shown with slot formats 34, 28, respectively, any particular subframe may be configured with any of the various available slot formats 0-61. Slot formats 0, 1 are all DL, UL, respectively. Other slot formats 2-61 include a mix of DL, UL, and flexible symbols. UEs are configured with the slot format (dynamically through DCI, or semi-statically/statically through radio resource control (RRC) signaling) through a received slot format indicator (SFI) . Note that the description infra applies also to a 5G/NR frame structure that is TDD.

Other wireless communication technologies may have a different frame structure and/or different channels. A frame (10 ms) may be divided into 10 equally sized subframes (1 ms) . Each subframe may include one or more time slots. Subframes may also include mini-slots, which may include 7, 4, or 2 symbols. Each slot may include 7 or 14 symbols, depending on the slot configuration. For slot configuration 0, each slot may include 14 symbols, and for slot configuration 1, each slot may include 7 symbols. The symbols on DL may be cyclic prefix (CP) OFDM (CP-OFDM) symbols. The symbols on UL may be CP-OFDM symbols (for high throughput scenarios) or discrete Fourier transform (DFT) spread OFDM (DFT-s-OFDM) symbols (also referred to as single carrier frequency-division multiple access (SC-FDMA) symbols) (for power limited scenarios; limited to a single stream transmission) . The number of slots within a subframe is based on the slot configuration and the numerology. For slot configuration 0, different numerologies μ0 to 5 allow for 1, 2, 4, 8, 16, and 32 slots, respectively, per subframe. For slot configuration 1, different numerologies 0 to 2 allow for 2, 4, and 8 slots, respectively, per subframe. Accordingly, for slot configuration 0 and numerology μ, there are 14 symbols/slot and 2 ^μ slots/subframe. The subcarrier spacing and symbol length/duration are a function of the numerology. The subcarrier spacing may be equal to 2 ^μ*15 kHz, where μ is the numerology 0 to 5. As such, the numerology μ=0 has a subcarrier spacing of 15 kHz and the numerology μ=5 has a subcarrier spacing of 480 kHz. The symbol length/duration is inversely related to the subcarrier spacing. FIGs. 2A-2D provide an example of slot configuration 0 with 14 symbols per slot and numerology 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.

A resource grid may be used to represent the frame structure. Each time slot includes a resource block (RB) (also referred to as physical RBs (PRBs) ) that extends 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. As illustrated in FIG. 2A, some of the REs carry reference (pilot) signals (RS) for the UE.The RS may include demodulation RS (DMRS) (indicated as R _x for one particular configuration, where 100x is the port number, but other DMRS configurations are possible) and channel state information reference signals (CSI-RS) for channel estimation at the UE. The RS may also include beam measurement RS (BRS) , beam refinement RS (BRRS) , and phase tracking RS (PT-RS) .

FIG. 2B illustrates an example of various DL channels within a subframe of a frame. The physical downlink control channel (PDCCH) carries DCI within one or more control channel elements (CCEs) , each CCE including nine RE groups (REGs) , each REG including four consecutive REs in an OFDM symbol. A primary synchronization signal (PSS) may be within symbol 2 of particular subframes of a frame. The PSS is used by a UE 104 to determine subframe/symbol timing and a physical layer identity. A secondary synchronization signal (SSS) may be within symbol 4 of particular subframes of a frame. The SSS is used by a UE to determine a 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 a physical cell identifier (PCI) . Based on the PCI, the UE can determine the locations of the aforementioned DMRS. The physical broadcast channel (PBCH) , which carries a master information block (MIB) , may be logically grouped with the PSS and SSS to form a synchronization signal (SS) /PBCH block. The MIB provides a number of RBs in the system bandwidth and a system frame number (SFN) . The physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted through the PBCH such as system information blocks (SIBs) , and paging messages.

As illustrated in FIG. 2C, some of the REs carry DMRS (indicated as R for one particular configuration, but other DMRS configurations are possible) for channel estimation at the base station. The UE may transmit DMRS for the physical uplink control channel (PUCCH) and DMRS for the physical uplink shared channel (PUSCH) . The PUSCH DMRS may be transmitted in the first one or two symbols of the PUSCH. The PUCCH DMRS may be transmitted in different configurations depending on whether short or long PUCCHs are transmitted and depending on the particular PUCCH format used. The UE may transmit sounding reference signals (SRS) . The SRS may be transmitted in the last symbol of a subframe. The SRS may have a comb structure, and a UE may transmit SRS on one of the combs. The SRS may be used by a base station for channel quality estimation to enable frequency-dependent scheduling on the UL.

FIG. 2D illustrates an example of various UL channels within a subframe of a frame. The PUCCH may be located as indicated in one configuration. The PUCCH carries uplink control information (UCI) , such as scheduling requests, a channel quality indicator (CQI) , a precoding matrix indicator (PMI) , a rank indicator (RI) , and HARQ ACK/NACK feedback. The PUSCH carries data, and may additionally be used to carry a buffer status report (BSR) , a power headroom report (PHR) , and/or UCI.

FIG. 3 is a block diagram of a base station 310 in communication with a UE 350 in an access network. In the DL, IP packets from the EPC 160 may be provided to a controller/processor 375. The controller/processor 375 implements layer 3 and layer 2 functionality. Layer 3 includes a radio resource control (RRC) layer, and layer 2 includes a service data adaptation protocol (SDAP) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. The controller/processor 375 provides RRC layer functionality associated with broadcasting of system information (e.g., MIB, SIBs) , 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 the transfer of upper layer packet data units (PDUs) , error correction through ARQ, concatenation, segmentation, and reassembly of RLC service data units (SDUs) , re-segmentation 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.

The transmit (TX) processor 316 and the receive (RX) processor 370 implement layer 1 functionality associated with various signal processing functions. Layer 1, which includes a physical (PHY) layer, may include error detection on the transport channels, forward error correction (FEC) coding/decoding of the transport channels, interleaving, rate matching, mapping onto physical channels, modulation/demodulation of physical channels, and MIMO antenna processing. The TX processor 316 handles mapping to signal constellations based on various modulation schemes (e.g., binary phase-shift keying (BPSK) , quadrature phase-shift keying (QPSK) , M-phase-shift keying (M-PSK) , M-quadrature amplitude modulation (M-QAM) ) . The coded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and/or frequency domain, and then combined together 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 produce multiple spatial streams. Channel estimates from a channel estimator 374 may be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimate 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 antenna 320 via a separate transmitter 318TX. Each transmitter 318TX may modulate an RF carrier with a respective spatial stream for transmission.

At the UE 350, each receiver 354RX receives a signal through its respective antenna 352. Each receiver 354RX recovers information modulated onto an RF carrier and provides the information to the receive (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. If multiple spatial streams are destined for the UE 350, they 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 comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, and the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the base station 310. These soft decisions may be based on channel estimates computed by the channel estimator 358. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the base station 310 on the physical channel. The data and control signals are then provided to the controller/processor 359, which implements layer 3 and layer 2 functionality.

The controller/processor 359 can 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, deciphering, header decompression, and control signal processing to recover IP packets from the EPC 160. The controller/processor 359 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

Similar to the functionality described in connection with the DL transmission by the base station 310, the controller/processor 359 provides RRC layer functionality associated with system information (e.g., MIB, SIBs) acquisition, RRC connections, and measurement reporting; PDCP layer functionality associated with header compression /decompression, and security (ciphering, deciphering, integrity protection, integrity verification) ; RLC layer functionality associated with the transfer of upper layer PDUs, error correction through ARQ, concatenation, segmentation, and reassembly of RLC SDUs, re-segmentation 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.

Channel estimates derived by a channel estimator 358 from a reference signal or feedback transmitted by the base station 310 may be used by the TX processor 368 to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the TX processor 368 may be provided to different antenna 352 via separate transmitters 354TX. Each transmitter 354TX may modulate an RF carrier with a respective spatial stream for transmission.

The UL transmission is processed at the base station 310 in a manner similar to that described in connection with the receiver function at the UE 350. Each receiver 318RX receives a signal through its respective antenna 320. Each receiver 318RX recovers information modulated onto an RF carrier and provides the information to a RX processor 370.

The controller/processor 375 can 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, deciphering, header decompression, control signal processing to recover IP packets from the UE 350. IP packets from the controller/processor 375 may be provided to the EPC 160. The controller/processor 375 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

In some aspects, at least one of the TX processor 368, the RX processor 356, and the controller/processor 359 may be configured to perform aspects in connection with (198) of FIG. 1.

In some other aspects, at least one of the TX processor 316, the RX processor 370, and the controller/processor 375 may be configured to perform aspects in connection with (198) of FIG. 1.

In an example RAT, such as Release 15/16 of 5G NR, a base station may schedule uplink data transmission by a UE using DCI. The base station may transmit a DCI message in order to schedule uplink transmission on an uplink data channel by the UE.The UE may transmit the uplink transmission as multiple coded bit parts on the uplink channel based on the DCI message. In particular, the UE may transmit each coded bit part via a respective layer set and, in some aspects, each layer set may correspond to an antenna panel with a beam of the UE.

However, some other UEs may each include multiple panels for uplink transmissions, such as with Releases 17+ of 5G NR. The diversity gain associated with communication by a UE may be improved through use of the multiple panels. Thus, a need exists for approaches to multi-panel uplink transmissions by UEs. FIGs. 4-10 describe various techniques and solutions to multi-panel uplink transmission by a UE through layer sweeping, which may improve diversity gain in wireless communication. For example, FIGs. 4-10 provide for configuring UEs with layer mapping patterns, and transmitting multiple coded parts of uplink transmissions based on layer mapping patterns.

FIG. 4 is a diagram illustrating an example of multi-panel uplink transmission scheduled by DCI 410 in a wireless communications system 400. According to various aspects, a base station may transmit DCI 410 to a UE. The DCI 410 may be a single message, and may schedule multiple simultaneous uplink transmissions on an uplink data channel, such as a PUSCH.

For multiple simultaneous uplink transmissions, the UE may include multiple panels, each including a set of antenna elements capable of generating a respective beam. A panel with a beam may correspond to a layer set, which may be a set of one or more (e.g., two) spatial layers. The UE and the base station may employ such layers for MIMO communication, e.g., with diversity.

As illustrated in FIG. 4, for example, layer set 1 412a may correspond to panel 1 with beam 1, and layer set 2 412b may correspond to panel 2 with beam 2. While only two layer sets respectively corresponding to two panels with two beams are illustrated, more than two layer sets respectively corresponding to more than two panels with more than two beams are possible without departing from the scope of the present disclosure.

Uplink data to be transmitted by the UE to the base station on the uplink data channel (e.g., PUSCH) may have several coded bit parts 420a-b. The UE may transmit each of the coded bit parts 420a-b using a beam from a panel when mapped onto the uplink data channel. That is, the UE uses a respective beam of each panel to transmit a respective one of the coded bit parts 420a-b of the uplink data transmission mapped on the uplink data channel.

As the base station may indicate the schedule for uplink transmission in the DCI 410, the DCI 410 may indicate a corresponding beam to be used for each coded bit part of the uplink transmission. The base station may indicate a beam by a transmission configuration indicator (TCI) associated with uplink transmission, a sounding resource indicator for codebook-based uplink MIMO, and/or a sounding resource set indicator for non-codebook-based uplink MIMO. For example, one of the uplink TCI, sounding resource indicator, or sounding resource set indicator may indicate one value (e.g., “A” ) for layer set 1 412a corresponding to panel 1/beam 1, or may indicate another value (e.g., “B” ) for layer set 2 412b corresponding to panel 2/beam 2. The uplink TCI can be provided by a reference signal, such as channel-state-information reference signal, sounding reference signal, and synchronization signal block.

Based on the DCI 510, the UE may map the uplink data channel for transmission to the base station. In some aspects, the UE may map the uplink data channel (e.g., PUSCH) according to the layer sets 412a-b first, frequency resources second, and time resources third. Precoding by the UE may occur after layer mapping, and the DCI 410 may further include information associated with precoding, such as a transmitted precoding matrix indicator (TPMI) index. Additionally, the DCI 410 may include information associated with DMRS on the uplink data channel, such as DMRS code-division multiplexing (CDM) group (s) , DMRS port (s) , and the like.

For example, if the DCI 410 includes information indicating that the TPMI index is 1, then four layer uplink MIMO is supported. Accordingly, the UE may map the uplink data channel onto the layer sets 412a-b for multi-panel transmission. For precoding, the UE may use a precoding matrix W, as shown in Table 1 for four-layer transmission using four antenna ports with transform precoding disabled.

TABLE 1

TABLE 1 (continued)

If the DCI 410 includes information indicating the DMRS port value is 0, then DMRS ports 0-3 and two DMRS CDM groups may be supported, as shown in Table 2 for antenna port (s) in which transform precoding is disabled, DMRS type is equal to 1, max length is equal to 2, and rank is equal to 4.

TABLE 2

In some aspects, the layer sets 412a-b on to which the coded bit parts 420a-b are to be mapped may be associated with DMRS on the uplink data channel, such as the DMRS group. For example, the DMRS group may be A or B. DMRS group A may indicate layer set 1 412a, whereas DMRS group B may indicate layer set 2 412b. Panel 1/beam 1 for coded bit part 1 420a may be use layer set 1 412a (e.g., layer 0, 1) with

DMRS ports

0, 1 and DMRS port group 0. Panel 2/beam 2 for coded bit part 2 420b may use layer set 2 412b (e.g., layer 2, 3) with

DMRS ports

2, 3 and DMRS port group 1. In effect, the UE may follow a layer mapping order based on

DMRS ports indications

0, 1, 2, 3.

FIG. 5 is a call flow diagram illustrating example operations associated with multi-panel uplink transmission by a UE 504 to a base station 502 in a wireless communications system 500. The UE 504 may be configured for multi-panel transmission on an uplink data channel (e.g., PUSCH) , and therefore, the UE 504 may include at least two panels 510a-b having a respective one of beams 512a-b.

The base station 502 may transmit DCI 522 to the UE 504. The DCI 522 may be associated with configuring uplink transmission by the UE 504 on the uplink data channel –for example, the DCI 522 may schedule multiple simultaneous uplink transmissions on the uplink data channel. In some aspects, the base station 502 may indicate at least one DMRS port group (s) in the DCI 522. The UE 504 may receive the DCI 522, and the UE 504 may map the uplink data channel based on the received DCI 522.

When the DCI 522 schedules uplink transmission by the UE 504, the UE 504 may generate multiple coded bit parts 532a-b of the uplink transmission. For example, each of the coded bit parts 532a-b may be a respective set of bits to be mapped onto the physical uplink data channel (e.g., PUSCH) . Potentially, the UE 504 may generate a respective coded bit part for each layer set to which the uplink data channel transmission can be mapped. As illustrated in FIG. 5, the UE 504 may generate two coded bit parts 532a-b; however, the UE 504 may be configured to generate more than two coded bit parts 532a-b in other aspects, such as when the UE 504 includes more than two panels 510a-b for multi-panel transmission.

The UE 504 may be configured to transmit multiple repetitions of the same multi-panel uplink transmission 530a-d, which each include the coded bit parts 532a-b. In some aspects, the base station 502 may configure the number of repetitions of the uplink transmission, and may indicate the number of repetitions in the DCI 522. In some other aspects, the UE 504 may obtain the number of repetitions from a higher layer (e.g., a protocol layer above the PHY layer of the UE 504) . While four repetitions are illustrated herein, other numbers of repetitions are possible without departing form the scope of the present disclosure.

According to various aspects, the UE 504 may determine at least one layer mapping pattern 526 based on the DCI 522. The at least one layer mapping pattern 526 may indicate a respective layer set to which each coded part of an uplink transmission is mapped, and a respective layer set may correspond to each of the panels 510a-b with each of the beams 512a-b. In some further aspects, the base station 502 may transmit an RRC message 524 to the UE 504 via RRC signaling 524 in association with the at least layer mapping pattern 526. Accordingly, the UE 504 may receive the RRC message 524, and may determine the at least one layer mapping pattern 526 based on the RRC message 524 in addition to the DCI 522.

Based on the at least one layer mapping pattern 526, the UE 504 may map the coded bit parts 532a-b of each repetition of the multi-panel uplink transmissions 530a-d to a layer set corresponding to one of the panels 510a-b with one of the beams 512a-b. The UE 504 may then sweep through the layer sets corresponding to the panels 510a-b with the beams 512a-b to transmit the coded bit parts 532a-b of each of the multi-panel uplink transmissions 530a-d.

The base station 502 may receive the coded bit parts 532a-b of the multi-panel uplink transmissions 530a-d on the uplink data channel from the UE 504. For example, the base station 502 may determine the at least one layer mapping pattern 526, and the base station 502 may receive the coded bit parts 532a-b of the multi-panel uplink transmissions 530a-d based on the at least one layer mapping pattern 526 configured for the UE 504.

In one aspect, each of the at least one layer mapping pattern 526 is predefined for a respective one of the multi-panel uplink transmissions 530a-d. For example, for four multi-panel uplink transmissions 530a-d, four layer mapping patterns may be predefined. Illustratively, referring to FIG. 6, a diagram illustrates an example of multi-panel uplink transmission 630a-d based on at least one layer mapping pattern that is predefined.

The base station 502 may transmit DCI 610 to the UE 504 in order to configure the multi-panel uplink transmissions 630a-d. Each of the multi-panel uplink transmissions 630a-d may be a repetition of the coded bit parts 620a-b. The UE 504 may transmit the coded bit parts 620a-b in each of the multi-panel uplink transmissions 630a-d by sweeping through the layer sets 612a-b respectively corresponding to the panels 510a-b with the beams 512a-b of the UE 504 based on a respective predefined layer mapping pattern of the at least one layer mapping pattern 526.

In some aspects, the UE 504 may determine the respective predefined layer mapping pattern associated with one of the multi-panel uplink transmissions 630a-d based on the DMRS port group order associated with each of the multi-panel uplink transmissions 630a-d. For example, the DMRS port group order may be DMRS port group “A” and then DMRS port group “B” and a first predefined layer mapping pattern may be (0, 1) for layer set 1 612a and then (2, 3) for layer set 2 612b. A second predefined layer mapping pattern may be (2, 3) for layer set 2 612b and then (0, 1) for layer set 1 612a. The second predefined layer mapping pattern may follow the DMRS port group order of “B” and then “A. ”

According to such a first predefined layer mapping pattern, the UE 504 may transmit the first multi-panel uplink transmission 630a by sweeping through layer set 1 612a of (0, 1) , corresponding to panel 1 510a/beam 1 512a with DMRS port group A, to transmit coded bit part 1 620a, and then layer set 2 612b of (2, 3) , corresponding to panel 2 510b/beam 2 512b with DMRS port group B, to transmit coded bit part 2 620b. Similarly, the UE 504 may transmit the third multi-panel uplink transmission 630c by sweeping through layer set 1 612a of (0, 1) , corresponding to panel 1 510a/beam 1 512a with DMRS port group A, to transmit coded bit part 1, and then layer set 2 612b of (2, 3) , corresponding to panel 2 510b/beam 2 512b with DMRS port group B to transmit coded bit part 2 620b.

In the illustrated example, however, the UE 504 may sweep through the layer sets 612a-b in a different (e.g., reverse) order for the second and fourth

multi-panel uplink transmissions

630b, 630d. That is, according to the second predefined layer mapping pattern, the UE 504 may transmit the second multi-panel uplink transmission 630b by sweeping through layer set 2 612b of (2, 3) , with DMRS port group B, and then layer set 1 612a of (0, 1) , with DMRS port group A. Similarly, the UE 504 may transmit the fourth multi-panel uplink transmission 630d by sweeping through layer set 2 612b of (2, 3) , with DMRS port group B, and then layer set 1 612a of (0, 1) , with DMRS port group A.

In another aspect, the at least one layer mapping pattern 526 may be supported by a field in DCI 522. The DCI field can be a redundancy version (RV) . For example, the base station 502 may include information indicating an RV in the DCI 522, and the UE 504 may determine the at least one layer sweeping pattern 526 based on the indication of the RV included in the DCI 522. The base station 502 may configure a layer mapping pattern for each RV value, and the base station 502 may include information indicating the layer mapping pattern corresponding to the RV value in the RRC message 524 transmitted to the UE 504.

The UE 504 may receive the DCI 522 and the RRC message 524 from the base station 502. Based on the DCI 522, the UE 504 may determine the RV value. Then, the UE 504 may determine the at least one layer mapping pattern 526 based on the information in the RRC message 524 indicating the layer mapping pattern corresponding to the RV value from the DCI 522. Referring to FIG. 7, a diagram illustrates an example of multi-panel uplink transmissions 730a-d based on at least one layer mapping pattern that is supported by an RV indication.

The base station 502 may transmit DCI 710a-d to the UE 504 in order to configure each of the multi-panel uplink transmissions 730a-d. Each of the multi-panel uplink transmissions 730a-d may be a repetition of the coded bit parts 720a-b. The UE 504 may transmit the coded bit parts 720a-b in each of the multi-panel uplink transmissions 730a-d by sweeping through the layer sets 712a-b respectively corresponding to the panels 510a-b with the beams 512a-b of the UE 504 based on a respective predefined layer mapping pattern of the at least one layer mapping pattern 526.

Each of the DCI 710a-d may indicate one RV value associated with the respective one of the multi-panel uplink transmissions 730a-d scheduled thereby. The UE 504 may then use one RV value for the respective one of the multi-panel uplink transmissions 730a-d, as well as to determine the respective layer mapping pattern used for layer sweeping by the UE 504 when transmitting the coded bit parts 720a-b. In some aspects, the UE 504 may receive one RRC message for each of the DCI 710a-d. In some other aspects, the UE 504 may receive one RRC message for each of the layer mapping patterns supported by the RV values indicated by the DCI 710a-d. Table 3 illustrates an example of layer mapping patterns supported by RV values, which may be indicated in one or more RRC messages transmitted by the base station 502 to the UE 504.

RV in DCI	RV used	Layer mapping pattern
RV=0	RV=0	A, B
RV=2	RV=2	A, B
RV=3	RV=3	B, A
RV=1	RV=1	B, A

TABLE 3

As shown in the example illustration, the base station 502 may transmit a first DCI 710a to schedule a first multi-panel uplink transmission 730a with an RV value of 0. The base station 502 may transmit an RRC message to indicate the RV value of 0 corresponds to layer mapping pattern (A, B) . The UE 504 may receive the first DCI 710a and the RRC message indicating the layer mapping pattern corresponding to the RV value indicated in the first DCI 710a.

The UE 504 may determine that the RV value to use for the first multi-panel uplink transmission 730a is 0 based on the first DCI 710a. Further, the UE 504 may determine that the layer mapping pattern to use for the first multi-panel uplink transmission 730a is (A, B) based on the first DCI 710a and the RRC message.

The UE 504 may determine that the layer mapping pattern (A, B) corresponds to layer mapping (0, 1) , (2, 3) . According to such a layer mapping pattern, the UE 504 may transmit the first multi-panel uplink transmission 730a by sweeping through layer set 1 712a of (0, 1) , corresponding to panel 1 510a/beam 1 512a, to transmit coded bit part 1 620a, and then layer set 2 612b of (2, 3) , corresponding to panel 2 510b/beam 2 512b, to transmit coded bit part 2 620b.

Similarly, the base station 502 may transmit a second DCI 710b to schedule a second multi-panel uplink transmission 730b with an RV value of 2. The base station 502 may transmit an RRC message to indicate the RV value of 2 corresponds to layer mapping pattern (A, B) . The UE 504 may receive the second DCI 710b and the RRC message and, based thereon, may determine that the RV value to use for the second multi-panel uplink transmission 730b is 2 and the layer mapping pattern to use is (A, B) .Thus, the UE 504 may transmit the second multi-panel uplink transmission 730a by sweeping through layer set 1 712a, corresponding to panel 1 510a/beam 1 512a, to transmit coded bit part 1 720a, and then layer set 2 712b, corresponding to panel 2 510b/beam 2 512b, to transmit coded bit part 2 720b.

The base station 502, however, may transmit a third DCI 710c to schedule a third multi-panel uplink transmission 730c with an RV value of 3. The base station 502 may transmit an RRC message to indicate the RV value of 3 corresponds to layer mapping pattern (B, A) . The UE 504 may receive the third DCI 710c and the RRC message and, based thereon, may determine that the RV value to use for the third multi-panel uplink transmission 730c is 3 and the layer mapping pattern to use is (B, A) .Thus, the UE 504 may transmit the third multi-panel uplink transmission 730c by sweeping through layer set 2 712b, corresponding to panel 2 510b/beam 2 512b, to transmit coded bit part 1 720a, and then layer set 1 712a, corresponding to panel 1 510a/beam 1 512a, to transmit coded bit part 2 720b.

Similarly, the base station 502 may transmit a fourth DCI 710d to schedule a fourth multi-panel uplink transmission 730d with an RV value of 1. The base station 502 may transmit an RRC message to indicate the RV value of 1 corresponds to layer mapping pattern (B, A) . The UE 504 may receive the fourth DCI 710d and the RRC message and, based thereon, may determine that the RV value to use for the fourth multi-panel uplink transmission 730d is 1 and the layer mapping pattern to use is (B, A) .Thus, the UE 504 may transmit the fourth multi-panel uplink transmission 730d by sweeping through layer set 2 712b, corresponding to panel 2 510b/beam 2 512b, to transmit coded bit part 1 720a, and then layer set 1 712a, corresponding to panel 1 510a/beam 1 512a, to transmit coded bit part 2 720b.

In still another aspect, the indication of layer sweeping for a multi-panel uplink transmission by the UE 504 may be supported in the DCI, e.g., either explicitly or implicitly. For the explicit support, the base station 502 may include a one-bit value in the DCI 522 to indicate the at least one layer mapping pattern 526. Thus, the UE 504 may determine the at least one layer mapping pattern 526 based on the one-bit value included in the DCI 522. For the explicit support, the at least one layer sweeping pattern 526 may follow a DMRS port indication in the DCI 522, such as a DMRS port order that indicates (0, 1) , (2, 3) or indicates (2, 3) , (0, 1) .

Referring to FIG. 8, the base station 502 may transmit a respective one of DCI 810a-d to schedule each of the multi-panel uplink transmissions 830a-d by the UE 504. The DCI 810a-d may each include a respective explicit indication of a layer mapping pattern (e.g., a one-bit value) or a respective implicit indication of a layer mapping pattern (e.g., a DMRS port group order) .

By way of example, one bit value (e.g., 0) may correspond to a first layer mapping pattern of (0, 1) , (2, 3) , as well as DMRS port group order A and B, whereas another bit value (e.g., 1) may correspond to a second layer mapping pattern of (2, 3) , (0, 1) , as well as DMRS port group order B and A. For the explicit indication, the bit value may be in a layer mapping field of each DCI 810a-d. For the implicit indication, the DMRS port group order of A, B may correspond to (0, 1) , (2, 3) , whereas B, A may correspond to (2, 3) , (0, 1) .

The base station 502 may transmit a first DCI 810a to schedule a first multi-panel uplink transmission 830a with one-bit value of 0 or a DMRS port group order of (A, B) , which may correspond to layer mapping pattern (0, 1) , (2, 3) . The UE 504 may receive the first DCI 810a and, based thereon, may determine that the layer mapping pattern to use is (0, 1) , (2, 3) . Thus, the UE 504 may transmit the first multi-panel uplink transmission 830a by sweeping through layer set 1 812a, corresponding to panel 1 510a/beam 1 512a, to transmit coded bit part 1 820a, and then layer set 2 812b, corresponding to panel 2 510b/beam 2 512b, to transmit coded bit part 2 820b.

However, the base station 502 may transmit a second DCI 810b to schedule a second multi-panel uplink transmission 830b with one-bit value of 1 or a DMRS port group order of (B, A) , which may correspond to layer mapping pattern (B, A) . The UE 504 may receive the second DCI 810b and, based thereon, may determine that the layer mapping pattern to use is (2, 3) , (0, 1) . Thus, the UE 504 may transmit the second multi-panel uplink transmission 830b by sweeping through layer set 2 812b, corresponding to panel 2 510b/beam 2 512b, to transmit coded bit part 1 820a, and then layer set 1 812a, corresponding to panel 1 510a/beam 1 512a, to transmit coded bit part 2 820b.

To schedule the third multi-panel uplink transmission 830c, the base station 502 may revert to the first layer mapping pattern and, therefore, may transmit a third DCI 810c with one-bit value of 0 or a DMRS port group order of (A, B) , which may correspond to layer mapping pattern (0, 1) , (2, 3) . The UE 504 may receive the third DCI 810c and, based thereon, may determine that the layer mapping pattern to use is (0, 1) , (2, 3) .The UE 504 may then transmit the third multi-panel uplink transmission 830c by sweeping through layer set 1 812a, corresponding to panel 1 510a/beam 1 512a, to transmit coded bit part 1 820a, and then layer set 2 812b, corresponding to panel 2 510b/beam 2 512b, to transmit coded bit part 2 820b.

When scheduling the fourth multi-panel uplink transmission 830d, the base station 502 may transmit a fourth DCI 810d with one-bit value of 1 or a DMRS port group order of (B, A) , which may correspond to layer mapping pattern (2, 3) , (0, 1) . The UE 504 may receive the fourth DCI 810d and, based thereon, may determine that the layer mapping pattern to use is (2, 3) , (0, 1) . Thus, the UE 504 may transmit the fourth multi-panel uplink transmission 830d by sweeping through layer set 2 812b, corresponding to panel 2 510b/beam 2 512b, to transmit coded bit part 1 820a, and then layer set 1 812a, corresponding to panel 1 510a/beam 1 512a, to transmit coded bit part 2 820b.

FIG. 9 is a flowchart of an example method 900 of wireless communication by a UE. The method 900 may be performed by a UE, such as the UE 104 of FIG. 1, the UE 350 of FIG. 3, and/or the UE 504 of FIG. 5. According to various aspects, one or more of the illustrated operations may be omitted, transposed, and/or contemporaneously performed.

At 902, the UE may receive, from a base station, DCI associated with configuring uplink transmission by the UE on an uplink data channel. For example, referring to FIG. 5, the UE 504 may receive, from the base station 502, the DCI 522 associated with configuring the multi-panel uplink transmissions 530a-d by the UE 504 on the uplink data channel (e.g., PUSCH) .

At 904, the UE may determine at least one layer mapping pattern based on the DCI. The at least one layer mapping pattern may indicate a respective layer set to which each coded part of the uplink transmission is mapped, and the respective layer set may correspond to a panel with a beam of the UE. For example, referring to FIG. 5, the UE 504 may determine the at least one layer mapping pattern 526 based on the DCI 522.

In one aspect, the at least one layer mapping a respective layer mapping pattern of the at least one layer mapping pattern may be predefined for each of at least two repetitions of the uplink transmission. In another aspect, to determine the at least one layer mapping pattern, the UE may determine an RV value based on the DCI, and the at least one layer mapping pattern may correspond to the RV value. In this other aspect, the UE may receive, via RRC signaling, information indicating the at least one layer mapping pattern that corresponds to the RV value.

In still another aspect, to determine the at least one layer mapping pattern, the UE may identify a bit value included in the DCI, and the at least one layer mapping pattern may be determined based on the bit value. For example, the bit value may correspond to a DMRS port group order, which the at least one layer mapping pattern may follow. In still a further aspect, to determine the at least one layer mapping pattern, the UE may determine a mapping order associated with a DMRS port group based on the DCI, and the at least one layer mapping pattern may correspond to the mapping order associated with a DMRS.

At 906, the UE may transmit at least two repetitions of each coded part of the uplink transmission on the uplink data channel to the base station based on the at least one layer mapping pattern. For example, referring to FIG. 5, the UE may transmit the multiple repetitions coded bit parts 532a-d in the multi-panel uplink transmissions 530a-d on the uplink data channel (e.g., PUSCH) to the base station 502 based on the at least one layer mapping pattern 526.

FIG. 10 is a flowchart of an example method 1000 of wireless communication by a base station. The method 1000 may be performed by a base station, such as the base station 102/180 of FIG. 1, the base station 310 of FIG. 3, and/or the base station 502 of FIG. 5. According to various aspects, one or more of the illustrated operations may be omitted, transposed, and/or contemporaneously performed.

At 1002, the base station may determine at least one layer mapping pattern associated with uplink transmission by a UE. In some aspects, the at least one layer mapping pattern may include a respective layer set to which each coded part of the uplink transmission is mapped, and the respective layer set corresponds to a panel with a beam of the UE. In one aspect, a respective layer mapping pattern of the at least one layer mapping pattern may be predefined for each of at least two repetitions of the uplink transmission from the UE. For example, referring to FIG. 5, the base station 502 may determine the at least one layer mapping pattern 526 associated with the multi-panel uplink transmissions 530a-d by the UE 504.

At 1004, the base station may transmit, to the UE, DCI configuring the uplink transmission by the UE. For example, referring to FIG. 5, the base station 502 may transmit, to the UE 504, the DCI 522 configuring the multi-panel uplink transmissions 530a-d. In some aspects, the DCI may include information indicating the at least one layer mapping pattern. For example, the base station may determine an RV value associated with the DCI, and the information indicating the at least one layer mapping pattern may include the RV value. Further to such an example, the base station may transmit, to the UE via RRC signaling, information indicating the at least one layer mapping pattern that corresponds to the RV value.

In another example, the base station may determine a bit value that corresponds to the at least one layer mapping pattern. The information indicating the at least one layer mapping pattern may include the bit value. Potentially, the bit value may correspond to a DMRS port group order. In still another example, the base station may determine a mapping order associated with a DMRS port group. The information indicating the at least one layer mapping pattern may include the mapping order associated with a DMRS.

At 1006, the base station may receive, from the UE, at least two repetitions of each coded part of the uplink transmission on an uplink data channel based on the at least one layer mapping pattern. For example, referring to FIG. 5, the base station 502 may receive, from the UE 504, the repetitions of the coded bit parts 532a-b in the multi-panel uplink transmissions 530a-d on the uplink data channel based on the at least one layer mapping pattern 526.

Further disclosure is included in the Appendix.

It is understood that the specific order or hierarchy of blocks in the processes /flowcharts disclosed is an illustration of example approaches. Based upon design preferences, it is understood that the specific order or hierarchy of blocks in the processes /flowcharts may be rearranged. Further, some blocks may be combined or omitted. The accompanying method claims present elements of the various blocks in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more. ” The word “exemplary” is used herein to mean “serving as an example, instance, or illustration. ” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C,”and “A, B, C, or any combination thereof” include any combination of A, B, and/or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module, ” “mechanism, ” “element, ” “device, ” and the like may not be a substitute for the word “means. ” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for. ”

NRUL MIMO Design

Present Disclosure

·Present disclosure: Support layer sweeping in multiple transmission of PUSCH scheduled by single DCl in multi-panel UL transmission

·Layer sweeping is across UL panels

·Layer sweeping is by

·Option1: predefined pattern

·Option2: jointly indicated with RV and layer sweeping

·Option3: layer sweeping indication in UL DCI

Claims

A method of wireless communication by a user equipment (UE) , comprising:

receiving, from a base station, downlink control information (DCI) associated with configuring uplink transmission by the UE on an uplink data channel;

determining at least one layer mapping pattern based on the DCI; and

transmitting at least two repetitions of each coded part of the uplink transmission on the uplink data channel to the base station based on the at least one layer mapping pattern.
The method of claim 1, wherein the at least one layer mapping pattern indicates a respective layer set to which each coded part of the uplink transmission is mapped, and wherein the respective layer set corresponds to a panel with a beam.
The method of claim 1, wherein a respective layer mapping pattern of the at least one layer mapping pattern is predefined for each of the at least two repetitions.
The method of claim 1, wherein the determining the at least one layer mapping pattern comprises:

determining a redundancy version based on the DCI,

wherein the at least one layer mapping pattern corresponds to the redundancy version.
The method of claim 4, further comprising:

receiving, via radio resource control (RRC) signaling, information indicating the at least one layer mapping pattern that corresponds to the redundancy version.
The method of claim 1, wherein the determining the at least one layer mapping pattern comprises:

identifying a bit value included in the DCI,

wherein the at least one layer mapping pattern is determined based on the bit value.
The method of claim 6, wherein the bit value corresponds to a demodulation reference signal (DMRS) port group order.
The method of claim 1, wherein the determining the at least one layer mapping pattern comprises:

determining a mapping order associated with a demodulation reference signal (DMRS) port group based on the DCI,

wherein the at least one layer mapping pattern corresponds to the mapping order associated with a demodulation reference signal (DMRS) .
A method of wireless communication by a base station, comprising:

determining at least one layer mapping pattern associated with uplink transmission by a user equipment (UE) ;

transmitting, to the UE, downlink control information (DCI) configuring the uplink transmission by the UE; and

receiving, from the UE, at least two repetitions of each coded part of the uplink transmission on an uplink data channel based on the at least one layer mapping pattern.
The method of claim 9, wherein the at least one layer mapping pattern comprises a respective layer set to which each coded part of the uplink transmission is mapped, and wherein the respective layer set corresponds to a panel with a beam of the UE.
The method of claim 9, wherein a respective layer mapping pattern of the at least one layer mapping pattern is predefined for each of the at least two repetitions.
The method of claim 9, wherein the DCI includes information indicating the at least one layer mapping pattern.
The method of claim 12, further comprising:

determining a redundancy version associated with the DCI,

wherein the information indicating the at least one layer mapping pattern comprises the redundancy version.
The method of claim 13, further comprising:

transmitting, to the UE via radio resource control (RRC) signaling, information indicating the at least one layer mapping pattern that corresponds to the redundancy version.
The method of claim 12, further comprising:

determining a bit value that corresponds to the at least one layer mapping pattern, wherein the information indicating the at least one layer mapping pattern comprises the bit value.
The method of claim 15, wherein the bit value corresponds to a demodulation reference signal (DMRS) port group order.
The method of claim 12, further comprising:

determining a mapping order associated with a demodulation reference signal (DMRS) port group,

wherein the information indicating the at least one layer mapping pattern comprises the mapping order associated with a demodulation reference signal (DMRS) .
An apparatus for wireless communication by a user equipment (UE) , comprising:

means for receiving, from a base station, downlink control information (DCI) associated with configuring uplink transmission by the UE on an uplink data channel;

means for determining at least one layer mapping pattern based on the DCI; and

means for transmitting at least two repetitions of each coded part of the uplink transmission on the uplink data channel to the base station based on the at least one layer mapping pattern.
The apparatus of claim 18, wherein the at least one layer mapping pattern indicates a respective layer set to which each coded part of the uplink transmission is mapped, and wherein the respective layer set corresponds to a panel with a beam.
The apparatus of claim 18, wherein a respective layer mapping pattern of the at least one layer mapping pattern is predefined for each of the at least two repetitions.
The apparatus of claim 18, wherein the means for determining the at least one layer mapping pattern is configured to:

determine a redundancy version based on the DCI,

wherein the at least one layer mapping pattern corresponds to the redundancy version.
The apparatus of claim 21, further comprising:

means for receiving, via radio resource control (RRC) signaling, information indicating the at least one layer mapping pattern that corresponds to the redundancy version.
The apparatus of claim 18, wherein the means for determining the at least one layer mapping pattern is configured to:

identify a bit value included in the DCI,

wherein the at least one layer mapping pattern is determined based on the bit value.
The apparatus of claim 23, wherein the bit value corresponds to a demodulation reference signal (DMRS) port group order.
The apparatus of claim 18, wherein the means for determining the at least one layer mapping pattern is configured to:

determine a mapping order associated with a demodulation reference signal (DMRS) port group based on the DCI,

wherein the at least one layer mapping pattern corresponds to the mapping order associated with a demodulation reference signal (DMRS) .
An apparatus for wireless communication by a user equipment (UE) , comprising:

a memory; and

at least one processor coupled to the memory and configured to:

receive, from a base station, downlink control information (DCI) associated with configuring uplink transmission by the UE on an uplink data channel;

determine at least one layer mapping pattern based on the DCI; and

transmit at least two repetitions of each coded part of the uplink transmission on the uplink data channel to the base station based on the at least one layer mapping pattern.
The apparatus of claim 26, wherein the at least one layer mapping pattern indicates a respective layer set to which each coded part of the uplink transmission is mapped, and wherein the respective layer set corresponds to a panel with a beam.
The apparatus of claim 26, wherein a respective layer mapping pattern of the at least one layer mapping pattern is predefined for each of the at least two repetitions.
The apparatus of claim 26, wherein the determination of the at least one layer mapping pattern comprises to:

determine a redundancy version based on the DCI,

wherein the at least one layer mapping pattern corresponds to the redundancy version.
The apparatus of claim 29, wherein the at least one processor is further configured to:

receive, via radio resource control (RRC) signaling, information indicating the at least one layer mapping pattern that corresponds to the redundancy version.
The apparatus of claim 26, wherein the determination of the at least one layer mapping pattern comprises to:

identify a bit value included in the DCI,

wherein the at least one layer mapping pattern is determined based on the bit value.
The apparatus of claim 31, wherein the bit value corresponds to a demodulation reference signal (DMRS) port group order.
The apparatus of claim 26, wherein the determination of the at least one layer mapping pattern comprises to:

determine a mapping order associated with a demodulation reference signal (DMRS) port group based on the DCI,

wherein the at least one layer mapping pattern corresponds to the mapping order associated with a demodulation reference signal (DMRS) .
A computer-readable medium storing computer-executable code for wireless communication by a user equipment (UE) , the code when executed by a processor cause the processor to:

receive, from a base station, downlink control information (DCI) associated with configuring uplink transmission by the UE on an uplink data channel;

determine at least one layer mapping pattern based on the DCI; and

transmit at least two repetitions of each coded part of the uplink transmission on the uplink data channel to the base station based on the at least one layer mapping pattern.
An apparatus for wireless communication by a base station, comprising:

means for determining at least one layer mapping pattern associated with uplink transmission by a user equipment (UE) ;

means for transmitting, to the UE, downlink control information (DCI) configuring the uplink transmission by the UE; and

means for receiving, from the UE, at least two repetitions of each coded part of the uplink transmission on an uplink data channel based on the at least one layer mapping pattern.
The apparatus of claim 35, wherein the at least one layer mapping pattern comprises a respective layer set to which each coded part of the uplink transmission is mapped, and wherein the respective layer set corresponds to a panel with a beam of the UE.
The apparatus of claim 35, wherein a respective layer mapping pattern of the at least one layer mapping pattern is predefined for each of the at least two repetitions.
The apparatus of claim 35, wherein the DCI includes information indicating the at least one layer mapping pattern.
The apparatus of claim 38, further comprising:

means for determining a redundancy version associated with the DCI,

wherein the information indicating the at least one layer mapping pattern comprises the redundancy version.
The apparatus of claim 39, further comprising:

means for transmitting, to the UE via radio resource control (RRC) signaling, information indicating the at least one layer mapping pattern that corresponds to the redundancy version.
The apparatus of claim 38, further comprising:

means for determining a bit value that corresponds to the at least one layer mapping pattern,

wherein the information indicating the at least one layer mapping pattern comprises the bit value.
The apparatus of claim 41, wherein the bit value corresponds to a demodulation reference signal (DMRS) port group order.
The apparatus of claim 38, further comprising:

means for determining a mapping order associated with a demodulation reference signal (DMRS) port group,

wherein the information indicating the at least one layer mapping pattern comprises the mapping order associated with a demodulation reference signal (DMRS) .
An apparatus for wireless communication by a base station, comprising:

a memory; and

at least one processor coupled to the memory and configured to:

determine at least one layer mapping pattern associated with uplink transmission by a user equipment (UE) ;

transmit, to the UE, downlink control information (DCI) configuring the uplink transmission by the UE; and

receive, from the UE, at least two repetitions of each coded part of the uplink transmission on an uplink data channel based on the at least one layer mapping pattern.
The apparatus of claim 44, wherein the at least one layer mapping pattern comprises a respective layer set to which each coded part of the uplink transmission is mapped, and wherein the respective layer set corresponds to a panel with a beam of the UE.
The apparatus of claim 44, wherein a respective layer mapping pattern of the at least one layer mapping pattern is predefined for each of the at least two repetitions.
The apparatus of claim 44, wherein the DCI includes information indicating the at least one layer mapping pattern.
The apparatus of claim 47, wherein the at least one processor is further configured to:

determine a redundancy version associated with the DCI,

wherein the information indicating the at least one layer mapping pattern comprises the redundancy version.
The apparatus of claim 48, wherein the at least one processor is further configured to:

transmit, to the UE via radio resource control (RRC) signaling, information indicating the at least one layer mapping pattern that corresponds to the redundancy version.
The apparatus of claim 47, wherein the at least one processor is further configured to:

determine a bit value that corresponds to the at least one layer mapping pattern, wherein the information indicating the at least one layer mapping pattern comprises the bit value.
The apparatus of claim 50, wherein the bit value corresponds to a demodulation reference signal (DMRS) port group order.
The apparatus of claim 47, wherein the at least one processor is further configured to:

determine a mapping order associated with a demodulation reference signal (DMRS) port group,

wherein the information indicating the at least one layer mapping pattern comprises the mapping order associated with a demodulation reference signal (DMRS) .
A computer-readable medium storing computer-executable code for wireless communication by a base station, the code when executed by a processor cause the processor to:

determine at least one layer mapping pattern associated with uplink transmission by a user equipment (UE) ;

transmit, to the UE, downlink control information (DCI) configuring the uplink transmission by the UE; and

receive, from the UE, at least two repetitions of each coded part of the uplink transmission on an uplink data channel based on the at least one layer mapping pattern.