Patent ID: 12224964

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 include 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 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.

While aspects and implementations are described in this application by illustration to some examples, those skilled in the art will understand that additional implementations and use cases may come about in many different arrangements and scenarios. Innovations described herein may be implemented across many differing platform types, devices, systems, shapes, sizes, and packaging arrangements. For example, implementations and/or uses may come about via integrated chip implementations and other non-module-component based devices (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail/purchasing devices, medical devices, artificial intelligence (AI)-enabled devices, etc.). While some examples may or may not be specifically directed to use cases or applications, a wide assortment of applicability of described innovations may occur. Implementations may range a spectrum from chip-level or modular components to non-modular, non-chip-level implementations and further to aggregate, distributed, or original equipment manufacturer (OEM) devices or systems incorporating one or more aspects of the described innovations. In some practical settings, devices incorporating described aspects and features may also include additional components and features for implementation and practice of claimed and described aspect. For example, transmission and reception of wireless signals necessarily includes a number of components for analog and digital purposes (e.g., hardware components including antenna, RF-chains, power amplifiers, modulators, buffer, processor(s), interleaver, adders/summers, etc.). It is intended that innovations described herein may be practiced in a wide variety of devices, chip-level components, systems, distributed arrangements, aggregated or disaggregated components, end-user devices, etc. of varying sizes, shapes, and constitution.

FIG.1is a diagram illustrating an example of a wireless communications system and an access network100. The wireless communications system (also referred to as a wireless wide area network (WWAN)) includes base stations102, UEs104, an Evolved Packet Core (EPC)160, and another core network190(e.g., a 5G Core (5GC)). The base stations102may 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 stations102configured for 4G LTE (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)) may interface with the EPC160through first backhaul links132(e.g., S1 interface). The base stations102configured for 5G NR (collectively referred to as Next Generation RAN (NG-RAN)) may interface with core network190through second backhaul links184. In addition to other functions, the base stations102may 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 stations102may communicate directly or indirectly (e.g., through the EPC160or core network190) with each other over third backhaul links134(e.g., X2 interface). The first backhaul links132, the second backhaul links184(e.g., an Xn interface), and the third backhaul links134may be wired or wireless.

In some aspects, a base station102or180may be referred as a RAN and may include aggregated or disaggregated components. As an example of a disaggregated RAN, a base station may include a central unit (CU)106, one or more distributed units (DU)105, and/or one or more remote units (RU)109, as illustrated inFIG.1. A RAN may be disaggregated with a split between an RU109and an aggregated CU/DU. A RAN may be disaggregated with a split between the CU106, the DU105, and the RU109. A RAN may be disaggregated with a split between the CU106and an aggregated DU/RU. The CU106and the one or more DUs105may be connected via an F1 interface. A DU105and an RU109may be connected via a fronthaul interface. A connection between the CU106and a DU105may be referred to as a midhaul, and a connection between a DU105and an RU109may be referred to as a fronthaul. The connection between the CU106and the core network may be referred to as the backhaul. The RAN may be based on a functional split between various components of the RAN, e.g., between the CU106, the DU105, or the RU109. The CU may be configured to perform one or more aspects of a wireless communication protocol, e.g., handling one or more layers of a protocol stack, and the DU(s) may be configured to handle other aspects of the wireless communication protocol, e.g., other layers of the protocol stack. In different implementations, the split between the layers handled by the CU and the layers handled by the DU may occur at different layers of a protocol stack. As one, non-limiting example, a DU105may provide a logical node to host a radio link control (RLC) layer, a medium access control (MAC) layer, and at least a portion of a physical (PHY) layer based on the functional split. An RU may provide a logical node configured to host at least a portion of the PHY layer and radio frequency (RF) processing. A CU106may host higher layer functions, e.g., above the RLC layer, such as a service data adaptation protocol (SDAP) layer, a packet data convergence protocol (PDCP) layer. In other implementations, the split between the layer functions provided by the CU, DU, or RU may be different.

An access network may include one or more integrated access and backhaul (IAB) nodes111that exchange wireless communication with a UE104or other IAB node111to provide access and backhaul to a core network. In an IAB network of multiple IAB nodes, an anchor node may be referred to as an IAB donor. The IAB donor may be a base station102or180that provides access to a core network190or EPC160and/or control to one or more IAB nodes111. The IAB donor may include a CU106and a DU105. IAB nodes111may include a DU105and a mobile termination (MT). The DU105of an IAB node111may operate as a parent node, and the MT may operate as a child node.

The base stations102may wirelessly communicate with the UEs104. Each of the base stations102may provide communication coverage for a respective geographic coverage area110. There may be overlapping geographic coverage areas110. For example, the small cell102′ may have a coverage area110′ that overlaps the coverage area110of one or more macro base stations102. 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 links120between the base stations102and the UEs104may include uplink (UL) (also referred to as reverse link) transmissions from a UE104to a base station102and/or downlink (DL) (also referred to as forward link) transmissions from a base station102to a UE104. The communication links120may 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 stations102/UEs104may 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 UEs104may communicate with each other using device-to-device (D2D) communication link158. The D2D communication link158may use the DL/UL WWAN spectrum. The D2D communication link158may 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, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, LTE, or NR.

The wireless communications system may further include a Wi-Fi access point (AP)150in communication with Wi-Fi stations (STAs)152via communication links154, e.g., in a 5 GHz unlicensed frequency spectrum or the like. When communicating in an unlicensed frequency spectrum, the STAs152/AP150may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.

The small cell102′ may operate in a licensed and/or an unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell102′ may employ NR and use the same unlicensed frequency spectrum (e.g., 5 GHz, or the like) as used by the Wi-Fi AP150. The small cell102′, employing NR in an unlicensed frequency spectrum, may boost coverage to and/or increase capacity of the access network.

The electromagnetic spectrum is often subdivided, based on frequency/wavelength, into various classes, bands, channels, etc. 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 referred to (interchangeably) as a “sub-6 GHz” band in various documents and articles. A similar nomenclature issue sometimes occurs with regard to FR2, which is often referred to (interchangeably) as a “millimeter wave” band in documents and articles, despite being different from the extremely high frequency (EHF) band (30 GHz-300 GHz) which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band.

The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Recent 5G NR studies have identified an operating band for these mid-band frequencies as frequency range designation FR3 (7.125 GHz-24.25 GHz). Frequency bands falling within FR3 may inherit FR1 characteristics and/or FR2 characteristics, and thus may effectively extend features of FR1 and/or FR2 into mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operation beyond 52.6 GHz. For example, three higher operating bands have been identified as frequency range designations FR2-2 (52.6 GHz-71 GHz), FR4 (71 GHz-114.25 GHz), and FR5 (114.25 GHz-300 GHz). Each of these higher frequency bands falls within the EHF band.

With the above aspects in mind, unless specifically stated otherwise, it should be understood that the term “sub-6 GHz” or the like if used herein may broadly represent frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. Further, unless specifically stated otherwise, it should be understood that the term “millimeter wave” or the like if used herein may broadly represent frequencies that may include mid-band frequencies, may be within FR2, FR4, FR2-2, and/or FR5, or may be within the EHF band.

A base station102, whether a small cell102′ 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 gNB180may operate in a traditional sub 6 GHz spectrum, in millimeter wave frequencies, and/or near millimeter wave frequencies in communication with the UE104. When the gNB180operates in millimeter wave or near millimeter wave frequencies, the gNB180may be referred to as a millimeter wave base station. The millimeter wave base station180may utilize beamforming182with the UE104to compensate for the path loss and short range. The base station180and the UE104may each include a plurality of antennas, such as antenna elements, antenna panels, and/or antenna arrays to facilitate the beamforming.

The base station180may transmit a beamformed signal to the UE104in one or more transmit directions182′. The UE104may receive the beamformed signal from the base station180in one or more receive directions182″. The UE104may also transmit a beamformed signal to the base station180in one or more transmit directions. The base station180may receive the beamformed signal from the UE104in one or more receive directions. The base station180/UE104may perform beam training to determine the best receive and transmit directions for each of the base station180/UE104. The transmit and receive directions for the base station180may or may not be the same. The transmit and receive directions for the UE104may or may not be the same.

The EPC160may include a Mobility Management Entity (MME)162, other MMEs164, a Serving Gateway166, a Multimedia Broadcast Multicast Service (MBMS) Gateway168, a Broadcast Multicast Service Center (BM-SC)170, and a Packet Data Network (PDN) Gateway172. The MME162may be in communication with a Home Subscriber Server (HSS)174. The MME162is the control node that processes the signaling between the UEs104and the EPC160. Generally, the MME162provides bearer and connection management. All user Internet protocol (IP) packets are transferred through the Serving Gateway166, which itself is connected to the PDN Gateway172. The PDN Gateway172provides UE IP address allocation as well as other functions. The PDN Gateway172and the BM-SC170are connected to the IP Services176. The IP Services176may include the Internet, an intranet, an IP Multimedia Subsystem (IMS), a PS Streaming Service, and/or other IP services. The BM-SC170may provide functions for MBMS user service provisioning and delivery. The BM-SC170may 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 Gateway168may be used to distribute MBMS traffic to the base stations102belonging 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 network190may include an Access and Mobility Management Function (AMF)192, other AMFs193, a Session Management Function (SMF)194, and a User Plane Function (UPF)195. The AMF192may be in communication with a Unified Data Management (UDM)196. The AMF192is the control node that processes the signaling between the UEs104and the core network190. Generally, the AMF192provides QoS flow and session management. All user Internet protocol (IP) packets are transferred through the UPF195. The UPF195provides UE IP address allocation as well as other functions. The UPF195is connected to the IP Services197. The IP Services197may include the Internet, an intranet, an IP Multimedia Subsystem (IMS), a Packet Switch (PS) Streaming (PSS) Service, and/or other IP services.

The base station102may 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, BSS, an ESS, a TRP, network node, network entity, network equipment, or some other suitable terminology. The base station102can be implemented as an IAB node, a relay node, a sidelink node, an aggregated (monolithic) base station with a baseband unit (BBU) (including a CU and a DU) and an RU, or as a disaggregated base station including one or more of a CU, a DU, and/or an RU.

Examples of UEs104include 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 UEs104may be referred to as IoT devices (e.g., parking meter, gas pump, toaster, vehicles, heart monitor, etc.). The UE104may 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. In some scenarios, the term UE may also apply to one or more companion devices such as in a device constellation arrangement. One or more of these devices may collectively access the network and/or individually access the network.

Referring again toFIG.1, in certain aspects, the UE104may be configured to dynamically transmit an ACK/NACK response using one of a plurality of feedback resources via a dynamic ACK/NACK transmission component198. In certain aspects, the base station180may be configured to dynamically receive an ACK/NACK response using one of a plurality of feedback resources via a dynamic ACK/NACK reception component199. Although the following description may be focused on 5G NR, the concepts described herein may be applicable to other similar areas, such as LTE, LTE-A, CDMA, GSM, and other wireless technologies.

Deployment of communication systems, such as 5G new radio (NR) systems, may be arranged in multiple manners with various components or constituent parts. In a 5G NR system, or network, a network node, a network entity, a mobility element of a network, a 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) performing base station functionality, may be implemented in an aggregated or disaggregated architecture. For example, a BS (such as a Node B (NB), eNB, NR BS, 5G NB, access point (AP), a transmit receive point (TRP), or a cell, etc.) may be implemented as an aggregated base station (also known as a standalone BS or a monolithic BS) or a disaggregated base station.

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

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

FIG.2Ais a diagram200illustrating an example of a first subframe within a 5G NR frame structure.FIG.2Bis a diagram230illustrating an example of DL channels within a 5G NR subframe.FIG.2Cis a diagram250illustrating an example of a second subframe within a 5G NR frame structure.FIG.2Dis a diagram280illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure may be frequency division duplexed (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 time division duplexed (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 byFIGS.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 F is flexible for use between DL/UL, and subframe 3 being configured with slot format 1 (with all UL). While subframes 3, 4 are shown with slot formats 1, 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 DL control information (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.

FIGS.2A-2Dillustrate a frame structure, and the aspects of the present disclosure may be applicable to other wireless communication technologies, which 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 14 or 12 symbols, depending on whether the cyclic prefix (CP) is normal or extended. For normal CP, each slot may include 14 symbols, and for extended CP, each slot may include 12 symbols. The symbols on DL may be CP orthogonal frequency division multiplexing (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 CP and the numerology. The numerology defines the subcarrier spacing (SCS) and, effectively, the symbol length/duration, which is equal to 1/SCS.

SCSμΔf = 2μ· 15 [kHz]Cyclic prefix015Normal130Normal260Normal,Extended3120Normal4240Normal

For normal CP (14 symbols/slot), different numerologies μ to 4 allow for 1, 2, 4, 8, and 16 slots, respectively, per subframe. For extended CP, the numerology 2 allows for 4 slots per subframe. Accordingly, for normal CP and numerology μ, there are 14 symbols/slot and 2μslots/subframe. The subcarrier spacing may be equal to 2μ*15 kHz, where μ is the numerology 0 to 4. As such, the numerology μ=0 has a subcarrier spacing of 15 kHz and the numerology μ=4 has a subcarrier spacing of 240 kHz. The symbol length/duration is inversely related to the subcarrier spacing.FIGS.2A-2Dprovide an example of normal CP 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. Within a set of frames, there may be one or more different bandwidth parts (BWPs) (seeFIG.2B) that are frequency division multiplexed. Each BWP may have a particular numerology and CP (normal or extended).

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 inFIG.2A, some of the REs carry reference (pilot) signals (RS) for the UE. The RS may include demodulation RS (DM-RS) (indicated as R for one particular configuration, but other DM-RS 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.2Billustrates 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) (e.g., 1, 2, 4, 8, or 16 CCEs), each CCE including six RE groups (REGs), each REG including 12 consecutive REs in an OFDM symbol of an RB. A PDCCH within one BWP may be referred to as a control resource set (CORESET). A UE is configured to monitor PDCCH candidates in a PDCCH search space (e.g., common search space, UE-specific search space) during PDCCH monitoring occasions on the CORESET, where the PDCCH candidates have different DCI formats and different aggregation levels. Additional BWPs may be located at greater and/or lower frequencies across the channel bandwidth. A primary synchronization signal (PSS) may be within symbol 2 of particular subframes of a frame. The PSS is used by a UE104to 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 DM-RS. 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 (also referred to as SS block (SSB)). 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 inFIG.2C, some of the REs carry DM-RS (indicated as R for one particular configuration, but other DM-RS configurations are possible) for channel estimation at the base station. The UE may transmit DM-RS for the physical uplink control channel (PUCCH) and DM-RS for the physical uplink shared channel (PUSCH). The PUSCH DM-RS may be transmitted in the first one or two symbols of the PUSCH. The PUCCH DM-RS 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.2Dillustrates 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 hybrid automatic repeat request (HARQ) acknowledgment (ACK) (HARQ-ACK) feedback (i.e., one or more HARQ ACK bits indicating one or more ACK and/or negative ACK (NACK)). 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.3is a block diagram of a base station310in communication with a UE350in an access network. In the DL, IP packets from the EPC160may be provided to a controller/processor375. The controller/processor375implements layer 3 and layer 2 functionality. Layer 3 includes an RRC layer, and layer 2 includes an SDAP layer, a PDCP layer, an RLC layer, and a MAC layer. The controller/processor375provides 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) processor316and the receive (Rx) processor370implement layer 1 functionality associated with various signal processing functions. Layer 1, which includes a 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 processor316handles 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 estimator374may 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 UE350. Each spatial stream may then be provided to a different antenna320via a separate transmitter318Tx. Each transmitter318Tx may modulate a radio frequency (RF) carrier with a respective spatial stream for transmission.

At the UE350, each receiver354Rx receives a signal through its respective antenna352. Each receiver354Rx recovers information modulated onto an RF carrier and provides the information to the receive (Rx) processor356. The Tx processor368and the Rx processor356implement layer 1 functionality associated with various signal processing functions. The Rx processor356may perform spatial processing on the information to recover any spatial streams destined for the UE350. If multiple spatial streams are destined for the UE350, they may be combined by the Rx processor356into a single OFDM symbol stream. The Rx processor356then converts the OFDM symbol stream from the time-domain to the frequency domain using a Fast Fourier Transform (FFT). The frequency domain signal may include 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 station310. These soft decisions may be based on channel estimates computed by the channel estimator358. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the base station310on the physical channel. The data and control signals are then provided to the controller/processor359, which implements layer 3 and layer 2 functionality.

The controller/processor359can be associated with a memory360that stores program codes and data. The memory360may be referred to as a computer-readable medium. In the UL, the controller/processor359provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets from the EPC160. The controller/processor359is 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 station310, the controller/processor359provides 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 estimator358from a reference signal or feedback transmitted by the base station310may be used by the Tx processor368to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the Tx processor368may be provided to different antenna352via separate transmitters354Tx. Each transmitter354Tx may modulate an RF carrier with a respective spatial stream for transmission.

The UL transmission is processed at the base station310in a manner similar to that described in connection with the receiver function at the UE350. Each receiver318Rx receives a signal through its respective antenna320. Each receiver318Rx recovers information modulated onto an RF carrier and provides the information to a Rx processor370.

The controller/processor375can be associated with a memory376that stores program codes and data. The memory376may be referred to as a computer-readable medium. In the UL, the controller/processor375provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets from the UE350. IP packets from the controller/processor375may be provided to the EPC160. The controller/processor375is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

At least one of the Tx processor368, the Rx processor356, and the controller/processor359may be configured to perform aspects in connection with dynamic ACK/NACK transmission component198ofFIG.1.

At least one of the Tx processor316, the Rx processor370, and the controller/processor375may be configured to perform aspects in connection with dynamic ACK/NACK reception component199ofFIG.1.

FIG.4is a diagram400illustrating another example of a wireless communications system and an access network. The illustrated wireless communications system includes a disaggregated base station architecture. The disaggregated base station architecture may include one or more CUs410that can communicate directly with a core network420via a backhaul link, or indirectly with the core network420through one or more disaggregated base station units (such as a Near-Real Time (Near-RT) RAN Intelligent Controller (RIC)425via an E2 link, or a Non-Real Time (Non-RT) RIC415associated with a Service Management and Orchestration (SMO) Framework405, or both). A CU410may communicate with one or more DUs430via respective midhaul links, such as an F1 interface. The DUs430may communicate with one or more RUs440via respective fronthaul links. The RUs440may communicate with respective UEs104via one or more radio frequency (RF) access links. In some implementations, the UE104may be simultaneously served by multiple RUs440.

Each of the units, i.e., the CUs410, the DUs430, the RUs440, as well as the Near-RT RICs425, the Non-RT RICs415, and the SMO Framework405, may include one or more interfaces or be coupled to one or more interfaces configured to receive or to transmit signals, data, or information (collectively, signals) via a wired or wireless transmission medium. Each of the units, or an associated processor or controller providing instructions to the communication interfaces of the units, can be configured to communicate with one or more of the other units via the transmission medium. For example, the units can include a wired interface configured to receive or to transmit signals over a wired transmission medium to one or more of the other units. Additionally, the units can include a wireless interface, which may include a receiver, a transmitter, or a transceiver (such as an RF transceiver), configured to receive or to transmit signals, or both, over a wireless transmission medium to one or more of the other units.

In some aspects, the CU410may host one or more higher layer control functions. Such control functions can include RRC, PDCP, SDAP, or the like. Each control function can be implemented with an interface configured to communicate signals with other control functions hosted by the CU410. The CU410may 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 implementations, the CU410can be logically split into one or more CU-UP units and one or more CU-CP units. The CU-UP unit can communicate bidirectionally with the CU-CP unit via an interface, such as an E1 interface when implemented in an O-RAN configuration. The CU410can be implemented to communicate with the DU430, as necessary, for network control and signaling.

The DU430may correspond to a logical unit that includes one or more base station functions to control the operation of one or more RUs440. In some aspects, the DU430may host one or more of an RLC layer, a MAC layer, and one or more high PHY layers (such as modules for FEC encoding and decoding, scrambling, modulation, demodulation, or the like) depending, at least in part, on a functional split, such as those defined by 3GPP. In some aspects, the DU430may further host one or more low PHY layers. Each layer (or module) can be implemented with an interface configured to communicate signals with other layers (and modules) hosted by the DU430, or with the control functions hosted by the CU410.

Lower-layer functionality can be implemented by one or more RUs440. In some deployments, an RU440, controlled by a DU430, may correspond to a logical node that hosts RF processing functions, or low-PHY layer functions (such as performing FFT, inverse iFFT, digital beamforming, physical random access channel (PRACH) extraction and filtering, or the like), or both, based at least in part on the functional split, such as a lower layer functional split. In such an architecture, the RU(s)440can be implemented to handle over the air (OTA) communication with one or more UEs104. In some implementations, real-time and non-real-time aspects of control and user plane communication with the RU(s)440can be controlled by the corresponding DU430. In some scenarios, this configuration can enable the DU(s)430and the CU410to be implemented in a cloud-based RAN architecture, such as a vRAN architecture.

The SMO Framework405may be configured to support RAN deployment and provisioning of non-virtualized and virtualized network elements. For non-virtualized network elements, the SMO Framework405may be configured to support the deployment of dedicated physical resources for RAN coverage requirements that may be managed via an operations and maintenance interface (such as an O1 interface). For virtualized network elements, the SMO Framework405may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud)490) to perform network element life cycle management (such as to instantiate virtualized network elements) via a cloud computing platform interface (such as an O2 interface). Such virtualized network elements can include, but are not limited to, CUs410, DUs430, RUs440and Near-RT RICs425. In some implementations, the SMO Framework405can communicate with a hardware aspect of a 4G RAN, such as an open eNB (O-eNB)411, via an O1 interface. Additionally, in some implementations, the SMO Framework405can communicate directly with one or more RUs440via an O1 interface. The SMO Framework405also may include a Non-RT RIC415configured to support functionality of the SMO Framework405.

The Non-RT RIC415may be configured to include a logical function that enables non-real-time control and optimization of RAN elements and resources, artificial intelligence (AI)/machine learning (ML) (AI/ML) workflows including model training and updates, or policy-based guidance of applications/features in the Near-RT RIC425. The Non-RT RIC415may be coupled to or communicate with (such as via an A1 interface) the Near-RT RIC425. The Near-RT RIC425may be configured to include a logical function that enables near-real-time control and optimization of RAN elements and resources via data collection and actions over an interface (such as via an E2 interface) connecting one or more CUs410, one or more DUs430, or both, as well as an O-eNB, with the Near-RT RIC425.

In some implementations, to generate AI/ML models to be deployed in the Near-RT RIC425, the Non-RT RIC415may receive parameters or external enrichment information from external servers. Such information may be utilized by the Near-RT RIC425and may be received at the SMO Framework405or the Non-RT RIC415from non-network data sources or from network functions. In some examples, the Non-RT RIC415or the Near-RT RIC425may be configured to tune RAN behavior or performance. For example, the Non-RT RIC415may monitor long-term trends and patterns for performance and employ AI/ML models to perform corrective actions through the SMO Framework405(such as reconfiguration via O1) or via creation of RAN management policies (such as A1 policies).

At least one of the CU410, the DU430, and the RU440may be referred to as a base station102. Accordingly, a base station102may include one or more of the CU410, the DU430, and the RU440(each component indicated with dotted lines to signify that each component may or may not be included in the base station102), or combination thereof. The base station102provides an access point to the core network420for a UE104. The base stations102may include macrocells (high power cellular base station) and/or small cells (low power cellular base station). The small cells include femtocells, picocells, and microcells. A network that includes both small cell and macrocells may be known as a heterogeneous network. A heterogeneous network may also include HeNBs, which may provide service to a restricted group known as a CSG. The communication links between the RUs440and the UEs104may include uplink (UL) (also referred to as reverse link) transmissions from a UE104to an RU440and/or downlink (DL) (also referred to as forward link) transmissions from an RU440to a UE104. The communication links 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 stations102/UEs104may 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 PCell and a secondary component carrier may be referred to as an SCell.

Certain UEs104may communicate with each other using D2D communication link458. The D2D communication link458may use the DL/UL WWAN spectrum. The D2D communication link458may use one or more sidelink channels, such as a PSBCH, a PSDCH, a PSSCH, and a PSCCH. D2D communication may be through a variety of wireless D2D communications systems, such as for example, Bluetooth, Wi-Fi based on the IEEE 802.11 standard, LTE, or NR.

The wireless communications system may further include a Wi-Fi AP450in communication with UEs104(i.e., STAs) via communication link454, e.g., in a 5 GHz unlicensed frequency spectrum or the like. When communicating in an unlicensed frequency spectrum, the UEs104/AP450may perform a CCA prior to communicating in order to determine whether the channel is available.

The base station102and the UE104may each include a plurality of antennas, such as antenna elements, antenna panels, and/or antenna arrays to facilitate beamforming. The base station102may transmit a beamformed signal482to the UE104in one or more transmit directions. The UE104may receive the beamformed signal from the base station102in one or more receive directions. The UE104may also transmit a beamformed signal484to the base station102in one or more transmit directions. The base station102may receive the beamformed signal from the UE104in one or more receive directions. The base station102/UE104may perform beam training to determine the best receive and transmit directions for each of the base station102/UE104. The transmit and receive directions for the base station102may or may not be the same. The transmit and receive directions for the UE104may or may not be the same.

A feedback resource for an ACK/NACK response may be scheduled based on a decoding time of a PDSCH. A decoding time of a PDSCH may depend on the type of UE decoding implementation (i.e., a decoding scheme that a UE uses to decode the PDSCH). For example, a UE may use a linear minimum mean square error (MMSE) decoding scheme to decode a downlink transmission. A MMSE decoding scheme may use less time or computation resources than other decoding schemes, but may result in a higher decoding failure rate. In another aspect, a UE may use a non-linear (NL) decoding scheme, such as a maximum likelihood type with different sizes of candidate modulations. An NL decoding scheme may use more time or computation resources than other decoding schemes, but may result in a lower decoding failure rate in some cases (i.e., may help decode some cases which an MMSE decoding scheme would miss decoding). In another aspect, a UE may use a decoding scheme that compensates for NL impairments due to a power amplifier (PA), which may also increase decoding time. Similar considerations may be made for a UE configured to use a low density parity check (LDPC) decoding step performed after a demodulation step when decoding a downlink transmission. For example, use of a first LDPC decoding scheme may use less time or computation resources than use of a second LDPC decoding scheme.

A UE may be configured to dynamically select an optimal decoder or decoding scheme to use for each PDSCH decoding occasion. For example, a UE may be configured to balance the trade-off between a decoding cost (e.g., time and/or power) and a decoding performance. In one aspect, a UE may select a decoding scheme that has a decoding performance metric that meets or exceeds a threshold performance value (e.g. likelihood of decoding success), which has a lowest decoding cost value (e.g., time, power, a weighted sum of both time and power). A UE may select an optimal decoder based on a real-time status, such as channel realizations (delay and/or Doppler profile), battery status of the UE, and/or a modulation and coding scheme (MCS). In other words, a UE may dynamically select a decoder based on one or more current environmental condition metrics. Any suitable environmental condition metrics may be used to trigger a selection of one decoder over another, such as a UE battery status, a type of encoder used by the network entity, or a determined channel delay. In one aspect, a UE may be configured to select a decoding scheme that has a lowest decoding power value in response to a battery status meeting or falling below a threshold power value. In one aspect, a UE may be configured to select a decoding scheme that has a lowest decoding time value in response to a channel delay meeting or exceeding a threshold time value. In one aspect, a UE may be configured to predict that an NL demodulation scheme provides less gain over an MMSE demodulation scheme based on one or more current condition metrics, and select the MMSE demodulation scheme in response to the prediction. In one aspect, a UE may be configured to predict that an NL demodulation scheme leads to successful decoding (or meets or exceeds a threshold likelihood value) while an MMSE demodulation scheme does not (or meets or is below a threshold likelihood value), and select the NL demodulation scheme in response to the prediction, even at the cost of a longer time cost and a higher power cost.

A network entity (e.g., a base station, a component of a base station, such as a CU, DU, or RU, or a combination of base station components) may or may not have access to all the information that a UE may use to make such a decision (e.g., decoder implementation, battery, channel realizations). A machine learning classification algorithm may be trained and implemented at a UE to make an optimal decision when only partial information is known by the UE. For example, a network node (NN) algorithm may be implemented by the UE to use a power delay profile (PDP) and a Doppler profile of a communication channel as an input to select a decoding scheme from various decoding scheme candidates for a series of transmissions in response to changes of environmental condition metrics of the communication channel over time.

FIG.5is a diagram500illustrating an example of a transmission feedback scenario for a CC520of a UE, such as UE104inFIGS.1and4or UE702inFIG.7, having a single ACK/NACK feedback resource at PUCCH536. The slots510show slot timing for the transmission feedback scenario from slot 0 to slot 4. At slot 0, the CC520may receive a PDCCH532which may carry DCI that schedules a downlink transmission, such as PDSCH534, in the same slot. The PDCCH532may use one symbol in the beginning of slot 0 while the PDSCH534may be scheduled using multiple symbols of slot 0, such as symbols 1-5 of slot 0. While PDSCH534is shown here as scheduled for slot 0, in other aspects a PDSCH may be scheduled in a different slot as the PDCCH (e.g. PDCCH in the first symbol of slot 0 and PDSCH in the first eight symbols of slot 2). The DCI of the PDCCH532may also indicate a feedback resource that the UE may use to transmit an ACK/NACK response—an ACK if the UE successfully decodes the downlink transmission, and a NACK if the UE fails to decode the downlink transmission. Here, the DCI of the PDCCH532may schedule a downlink transmission illustrated as PDSCH534, and may indicate a feedback resource illustrated as PUCCH536scheduled at slot 2 (e.g., the last one or two symbols of slot 2). After the UE decodes the downlink transmission of PDSCH534, the UE may transmit an ACK/NACK response based on the decoded downlink transmission using the feedback resource of PUCCH536. For example, the UE may transmit an ACK using a 1 and a NACK using a 0 during slot 2 via PUCCH536.

The time offset between the PDSCH534and its ACK/NACK feedback resource of PUCCH536resource may be dynamically selected and indicated in the scheduling DCI of the PDCCH532. A DCI field or sub-field (e.g., “PDSCH-to-HARQ_feedback timing indicator”) may be used to down-select a slot offset value from a preconfigured list. Such a list may have a value from 1 to 8 for DCI format 1_0. Such a list may be RRC configured, for example using PUCCH-Config.dl-DataToUL-ACK for DCI format 1_1. An RRC list having 8 values may contain values {1,2,3,4,5,6,7,8}. For a PDSCH assignment, the scheduling DCI of PDCCH532may down-select a value from the list, such that a PUCCH in slot N may be used to transmit an ACK/NACK response for the PDSCH534in slot {N−1, N−2, N−3, N−4, N−5, N−6, N−7, N−8}. Here, the DCI of the PDCCH532may select a slot that indicates a feedback resource having a 2-slot offset from the PDSCH534, scheduling slot 2 for the PUCCH536which may be used to transmit an ACK/NACK response based on decoding the PDSCH534.

Different PDSCH decoding schemes may require different decoding times. The potential decoding times for each decoding scheme may be used to determine when a feedback resource, such as PUCCH536, may be scheduled for the UE to transmit an ACK/NACK response. A network entity, such as a BS102or180inFIG.1or4, or a network entity704inFIG.7, may be configured to schedule an earlier feedback resource for a decoding scheme that has a shorter decoding time and may be configured to schedule a later feedback resource for a decoding scheme that has a longer decoding time. A network entity may not know a UE's selected decoding scheme when the network entity makes PDSCH scheduling, but may be configured to allocate at least one feedback resource in the PDSCH scheduling DCI for the UE to transmit an ACK/NACK response. For example, the UE's decision of what decoding scheme to use may be dependent upon real-time information (e.g., DL channel, battery power) that the network entity does not know. A network entity may be configured to schedule a feedback resource for an ACK/NACK response of a downlink transmission based on the longest possible decoding time (i.e., worst case scenario). For example, the network entity may have access to the decoding time, or minimum K1 value, for each decoding scheme that a UE may use (i.e., a set of minimum K1 values). The network entity may be configured to schedule the feedback resource to be at least as long as the greatest minimum K1 value of the set of minimum K1 values. Such a configuration may result in longer delays, as decoding schemes having long decoding times (e.g., an NL decoder) may be rarely used. In another aspect, the network entity may be configured to schedule a feedback resource for an ACK/NACK response of a downlink transmission based on the shortest possible decoding time (i.e., the shortest timeline). For example, if the network entity has access to the decoding time, or minimum K1 value, for each decoding scheme that a UE may, the network entity may be configured to schedule the feedback resource to be at least as long as the smallest minimum K1 value of the set of minimum K1 values. Such a configuration may prevent a UE from using an advanced decoding scheme having a longer decoding time, which may result in more re-transmissions (Re-Tx) due to avoidable decoding failures. Such an increase in Re-Tx transmissions may increase transmission delays, overhead, and/or power consumption in the system. Minimum K1 values may be obtained by either the UE or the network entity via a table, or may be generated by repeatedly decoding downlink transmissions using various decoding schemes.

FIG.6is a diagram600illustrating an alternative example of a transmission feedback scenario for a CC620of a UE, such as UE104inFIGS.1and4or UE702inFIG.7, having multiple ACK/NACK feedback resources at PUCCH636and PUCCH638. The slots610show slot timing for the transmission feedback scenario from slot 0 to slot 4. At slot 0, the CC620may receive a PDCCH632which may carry DCI that schedules a downlink transmission, such as the PDSCH634of the same slot. The DCI of the PDCCH632may also indicate a plurality of feedback resources that the UE may use to transmit an ACK/NACK response—an ACK if the UE successfully decodes the downlink transmission, and a NACK if the UE fails to decode the downlink transmission. Here, the DCI of the PDCCH632may schedule a downlink transmission illustrated as PDSCH634and may indicate a feedback resource 1 illustrated as PUCCH636at slot 2 and a feedback resource 2 illustrated as PUCCH638at slot 3. After the UE decodes the downlink transmission of PDSCH634, the UE may transmit an ACK/NACK response based on the decoded downlink transmission using either the feedback resource 1 of PUCCH636or the feedback resource 2 of PUCCH638. For example, the UE may transmit an ACK using a 1 and a NACK using a 0 using either the feedback resource 1 of PUCCH636scheduled for slot 2 or the feedback resource 2 of PUCCH638scheduled for slot 3.

A network entity, such as the BS102or180ofFIGS.1and4, or the network entity704inFIG.7, may be configured to schedule or allocate multiple feedback resources to a UE, such as the UE104ofFIG.1orFIG.4. For example, one feedback resource may be allocated for a shorter timeline decoder and another feedback resource may be allocated for a longer timeline. While only two feedback resources, feedback resource 1 of PUCCH636and feedback resource 2 of PUCCH638, are shown in diagram600, any number of feedback resources may be scheduled for a downlink transmission, such as the downlink transmission of PDSCH634. Allowing a flexible ACK/NACK response scheme may achieve an optimal trade-off point in terms of decoding time and performance. For example, to reduce delay, a UE may use the earlier possible A/N occasion to feedback if a shorter timeline decoder works out, or when a UE misses the scheduling PDCCH for the occasion. In other words, a UE104ofFIG.1orFIG.4may use the PUCCH636to transmit an ACK if the UE successfully uses a decoding scheme with a short timeline to decode the downlink transmission of PDSCH634, or a NACK if the UE does not successfully receive and/or decode the downlink transmission of PDSCH634. Alternatively, the UE104ofFIG.1orFIG.4may use the PUCCH638to transmit an ACK of the UE successfully uses a decoding scheme with a long timeline to decode the downlink transmission of PDSCH634, or a NACK if the UE does not successfully receive and/or decode the downlink transmission of PDSCH634. To allow for better performance, a longer decoding timeline may not be excluded in case that UE decides that NL will work best. In other words, the network entity may be configured to include a feedback resource corresponding with a longer decoding scheme, such as the PUCCH638, if the UE selects a decoding scheme with a longer timeline instead of a decoding scheme with a shorter timeline.

Each of the ACK/NACK feedback resources—feedback resource 1 of PUCCH636and feedback resource 2 of PUCCH638—may be associated with a decoding scheme and/or a minimum K1 value. For example, the PUCCH636may be scheduled to accommodate the time a UE takes to decode the PDSCH634using a first decoding scheme, and the PUCCH638may be scheduled to accommodate the time a UE takes to decode the PDSCH634using a second decoding scheme.

FIG.7illustrates a network connection flow diagram700showing a UE702configured to use a plurality of feedback resources to transmit an ACK/NACK response to a network entity704. The UE702may be configured to transmit an indication in a transmission712that the UE702supports receiving a plurality of feedback resources for a downlink transmission. For example, the UE702may indicate to the network entity704, such as a gNB, whether it supports the feature of having multiple potential ACK/NACK response occasions for a PDSCH. Such information may be transmitted, for example, as UE capability information. The network entity704may also transmit a signal in a transmission712that enables a configuration of the plurality of feedback resources for a PDSCH. Such signals may be transmitted, for example, as a portion of an RRC or a MAC-CE. For example, the network entity704may transmit an RRC in a transmission712to the UE702that includes a set of K1 values (e.g., in a list) where each element of the list may correspond to one or multiple K1 values. Additionally, or alternatively, the network entity704may transmit a MAC-CE in a transmission712to the UE702that enables or disables the feature of having multiple feedback resources for a downlink transmission. While the UE702and the network entity704are shown here as transmitting indication/signaling in a transmission712to support multiple feedback resources simultaneously, the UE702may transmit an indication before the network entity704transmits a signal, and/or vice-versa.

The indications transmitted by the UE702in a transmission712may include conditional triggers that will trigger use of one decoding scheme or another in response to a detected environmental condition. For example, a satisfied conditional trigger of an MCS value or a rank value meeting or falling below a threshold value may trigger use of an MMSE decoding scheme, or a satisfied conditional trigger of an MCS value or a rank value meeting or exceeding a threshold value may trigger use of an NL decoding scheme.

The network entity704may be configured to enable multiple feedback resources if it receives an indication from the UE702that the network entity704supports multiple feedback resources (e.g., UE capability information that indicates such support). Additionally, or alternatively, the UE702may be configured to enable multiple feedback resources if it receives a signal from the network entity704that the UE702supports multiple feedback resources (e.g., an RRC having a list or a set of K1 values). Additionally, or alternatively, the UE702and the network entity704may be preconfigured to enable multiple feedback resources, or may be configured to enable multiple feedback resources upon detecting a conditional trigger.

The UE702may be configured to transmit timing information in a transmission714of min K1 values associated with decoding schemes to the network entity704. For example, the UE702may indicate to the network entity704, such as a base station or a component of a base station, its capability of minimum K1 values for different decoder implementations. The minimum K1 values may be presented as time offsets between PDSCH and an ACK/NACK response. In one aspect, where the UE702reports two K1 values, the UE may report a first K1 value for an MMSE based demodulation scheme and a second K1 value for a NL based demodulation scheme. The network entity704may be configured to interpret receipt of a single K1 value from the UE702as an indication that the UE702does not support dynamic selection of a decoding scheme. The UE702may be configured to update and report such capability dynamically. The UE702may use conditional triggers to enable or disable decoding schemes to use for decoding a downlink transmission from the network entity704. For example, the UE702may determine that a battery level of the UE702has met or exceeded a threshold value, and in response may transmit timing information of a plurality of min K1 values in a transmission714. Alternatively, or additionally, the UE702may determine that a battery level of the UE702has met or fallen below a threshold value, and in response may transmit timing information of less min K1 values (e.g., disabling an NL based demodulation scheme), or just one K1 value, in a transmission714. The UE702may additionally or alternatively use such conditional triggers to trigger a transmission712to update the indication to the network entity704of whether the UE702supports multiple feedback resources.

The UE702may be configured to indicate to the network entity704, such as a base station or a component of a base station, any conditions a specific K1 value will or will not apply to. For example, the UE702may be configured to never use an NL demodulation scheme or decoding scheme or a larger timeline corresponding with the NL decoding scheme with an MCS value or rank value that meets or falls below a threshold value. The UE702may transmit an indication of such a conditional trigger to the network entity704, allowing the network entity704to determine that the UE702will not use the NL demodulation scheme (or decoding scheme or larger timeline corresponding with the NL decoding scheme) when the network entity704transmits a downlink transmission having an MCS value or rank value that meets or falls below a threshold value. In another aspect, the UE702may be configured to only use an NL demodulation scheme or decoding scheme or larger timeline corresponding with the NL decoding scheme with an MCS value or rank value that meets or exceeds a threshold value. The UE702may transmit an indication of such a conditional trigger to the network entity704, allowing the network entity704to determine that the UE702will use the NL demodulation scheme (or decoding scheme or larger timeline corresponding with the NL decoding scheme) when the network entity704transmits a downlink transmission having an MCS value or rank value that meets or exceeds a threshold value. The network entity704may then use such conditional triggers to predict what types of feedback resources to schedule (e.g., do not schedule feedback resources for a decoding scheme that the UE702will conditionally not use, or schedule feedback resources for a decoding scheme that the UE702will conditionally use).

At722, the network entity704may be configured to determine ACK/NACK timelines or feedback resources based on the min K1 values received from the UE702. For example, the network entity704may be configured to allocate or schedule a feedback resource for each min K1 value, where each min K1 value is associated with a decoding scheme. Additionally, or alternatively, the network entity704may be configured to allocate or schedule a feedback resource for each min K1 value that is conditionally possible based upon conditions detected by the network entity704.

The network entity704may be configured to transmit, in a transmission716, control information (e.g., DCI) that schedules a downlink transmission and indicates multiple feedback resources for the UE to use for the downlink transmission. For example, the network entity704may be configured to dynamically indicate multiple K1 values as time offsets in a scheduling DCI. The network entity704may set a field or sub-field in a DCI that may be used by the UE702to down-select one or more elements from an RRC list for each PDSCH (i.e., a selection of a K1 value from a set of K1 values). In one aspect, a field/sub-field in the DCI may select an element from the RRC list that includes multiple K1 values, or the field/sub-field may select multiple K1 values from the RRC list. In response, the UE702may be configured to select any of the indicated K1 values for use. In another aspect, the network entity704may be configured to schedule a DCI that contains multiple fields or subfields, where each field/sub-field may correspond to a candidate K1 value. The UE702may use each field/sub-field to down-select a K1 value from an RRC list, or from different RRC lists. For example, the UE702may be configured to use a field1 to select a K1 value from a list1 of a first RRC for a short timeline decoding scheme, and use a field2 to select a K1 value from a list2 of a second RRC, or from the same list1, for a long timeline decoding scheme. The field1 may designate list1 and the field2 may designate list2. In some aspects, the network entity704may be configured to use a reserved index for field2 under conditions where the network entity704is configured to schedule only one K1 candidate value, or feedback resource.

One or more K1 values may be implicitly or statically indicated to the UE702. For example, when the multiple feedback resource feature is enabled on the UE702and the network entity704and certain conditions are met for a scheduled PDSCH, one or more ACK/NACK response feedback resources may be implicitly allowed. A shorter K1 value (or associated decoding scheme) may be indicated in a DCI transmitted, in a transmission, in a transmission716, as control information and a longer K1 value (or associated decoding scheme) may be determined at724by the UE702and/or determined at725by the network entity704based on a UE capability report or as the largest one in one or more RRC lists of K1 values. In other words, one K1 value may be scheduled by a DCI transmitted by the network entity704, in a transmission716, while another K1 value may be implicitly scheduled by a conditional trigger. In one aspect, the network entity704may not need to transmit, in a transmission716, feedback resources to the UE702, as the feedback resources may be implicitly (e.g., via one or more conditional triggers) or statically indicated (e.g., via one or more RRC configurations).

At726the UE702may decode the downlink transmission718using a demodulation scheme, such as an MMSE decoding scheme or an NL decoding scheme. The UE702may determine what demodulation scheme to use using any of the means described herein, for example based on detecting that a conditional trigger of an environmental condition has been satisfied, to optimize a decoding cost, and/or to optimize a decoding performance. The UE may be configured to transmit an ACK/NACK response720using a feedback resource associated with the demodulation scheme.

At least two types of HARQ codebooks (CBs) may be used in 3GPP NR R15—CB type 1 or CB type 2.FIG.8shows a diagram800illustrating an example of a transmission feedback scenario for CC1820and CC2830of a UE, such as UE104inFIGS.1and4or UE702inFIG.7, configured to use a CB type 1. CC1820has a single ACK/NACK feedback resource at PUCCH828and CC2830has a single ACK/NACK feedback resource at PUCCH838. The slots810show the slot timing for the transmission feedback scenario in diagram800from slot 0 to slot 5. At slot 0, the CC1may receive a PDCCH821which may carry a first DCI (DCI 1) that schedules a downlink transmission (Rx 1) illustrated as PDSCH822. At slot 1 the network entity, such as BS102or180inFIG.1or4, or network entity704inFIG.7, may not have scheduled any activity for the UE, providing a not scheduled (NS)824slot. At slot 2, the CC1may receive a PDCCH825which may carry a second DCI (DCI 2) that schedules a downlink transmission (Rx 2) illustrated as PDSCH826. The DCI 1 and the DCI 2 of the PDCCH821and PDCCH825, respectively, may also indicate a feedback resource of PUCCH828at slot 3 that the UE may use to transmit ACK/NACK responses for each codebook group (CBG) received by the UE at PDSCH822and PDSCH826.

The UE may be configured to use a type 1, or a static CB, shown to the right of PUCCH828of CC1820. The CB may have a fixed number of ACK/NACK bits (i.e., CB size) regardless of a scheduling decision. For example, the UE may configure CC1820as having a maximum of four CBGs per transmission time interval (TTI), such as four bits per TTI—one bit per CBG. If fewer CBGs are scheduled, the UE may be configured to fill in NACKs for the remaining bits. For an ACK/NACK response occasion, the UE may further be configured to report associated slots for potential PDSCH scheduling. The UE may further be configured to report the same number of bits for each PDSCH occasion in the same CC or BWP. For example, for PDSCH822, where the UE failed to decode the 1stand 2ndCBG and successfully decoded the 3rdand 4thCBG, the UE may report 0011 as two NACKs for the 1stand 2ndfailed CBGs and two ACKs for the 3rdand 4thsuccessful CBGs. For NS824where the network entity failed to schedule any PDSCH, the UE may report 0000 as four NACKS for the unscheduled CBGs. For PDSCH822, where the UE successfully decoded the 1stand 2ndCBG and the network entity failed to schedule any transmission for the 3rdand 4thCBG, the UE may report 1100 as two ACKs for the 1stand 2ndsuccessful CBG and two NACKs for the 3rdand 4thunscheduled CBGs. Here, after the UE decodes the downlink transmission Rx 1 of PDSCH822(failing to decode the first two CBGs and successfully decoding the second two CBGs) and the downlink transmission Rx 2 of PDSCH826(successfully decoding the first two CBGs), the UE may transmit an ACK/NACK response for CC1based on the decoded downlink transmission using the feedback resource of PUCCH828with 001100001100, or [0011][0000][1100].

At slot 0, the CC2may receive a PDCCH831which may carry a first DCI (DCI 1) that schedules a downlink transmission (Rx 1) illustrated as PDSCH832. At slot 1, the CC2may be transmitted a PDCCH833which may carry a second DCI (DCI 2) that schedules a downlink transmission (Rx 2) illustrated as PDSCH834. At slot 2, the CC2may receive a PDCCH835which may carry a third DCI (DCI 3) that schedules a downlink transmission (Rx 3) illustrated as PDSCH836. The DCI 1, DCI 2, and DCI 3 of the PDCCH831, PDCCH833, and PDCCH825, respectively, may also indicate a feedback resource that the UE may use to transmit a ACK/NACK responses for each TB received by the UE, such as the ACK/NACK feedback resource of PUCCH838at slot 3.

The UE may configure CC2830as having one TB per TTI, such as one bit per TTI. For an ACK/NACK response occasion, the UE may further be configured to report associated slots for potential PDSCH scheduling. The UE may further be configured to report the same number of bits for each PDSCH occasion in the same CC or BWP. For example, for PDSCH832, where the UE succeeded in decoding the TB, the UE may report 1 as an ACK for the successful TB. For PDSCH834, where the UE failed to receive/decode the PDCCH833, the UE may report 0 as an NACK for an unscheduled (from the UE's perspective) TB or TTI. For PDSCH836, where the UE succeeded in decoding the TB, the UE may report 1 as an ACK for the successful TB. Here, after the UE successfully decodes the downlink transmission Rx 1 of PDSCH832, misses the scheduling DCI 2 of PDCCH833, and successfully decodes the downlink transmission Rx 3 of PDSCH836, the UE may transmit an ACK/NACK response for CC2based on the decoded downlink transmission using the feedback resource of PUCCH838with 101, or [1][0][1].

As previously explained, different PDSCH decoding schemes may require different decoding times, and only providing a single feedback resource per group of PDSCH downlink transmissions may introduce needless delays or decoding failures.FIG.9is a diagram900illustrating an alternative example of a transmission feedback scenario for a CC1920and CC2930of a UE, such as UE104inFIGS.1and4or UE702inFIG.7, configured to use a static CB type 1. CC1920has multiple ACK/NACK feedback resources, ACK/NACK feedback resource 1 at PUCCH928at slot 3 and ACK/NACK feedback resource 2 at PUCCH929at slot 4. CC2930also has multiple ACK/NACK feedback resources, ACK/NACK feedback resource 1 at PUCCH938at slot 3 and ACK/NACK feedback resource 2 at PUCCH939at slot 4.

The slots910show the slot timing for the transmission feedback scenario in diagram900from slot 0 to slot 5. At slot 0, the CC1may similarly receive a PDCCH921which may carry a first DCI (DCI 1) that schedules a downlink transmission (Rx 1) illustrated as PDSCH922. At slot 1 the network entity, such as BS102or180inFIG.1or4, or network entity704inFIG.7, may not have scheduled any activity for the UE, providing a not scheduled (NS)924slot. At slot 2, the CC1may receive a PDCCH925which may carry a second DCI (DCI 2) that schedules a downlink transmission (Rx 2) illustrated as PDSCH926. The DCI 1 and the DCI 2 of the PDCCH921and PDCCH925, respectively, may also indicate a plurality of feedback resources—feedback resource 1 at PUCCH928and feedback resource 2 at PUCCH929—that the UE may use to transmit ACK/NACK responses for each codebook group (CBG) received by the UE. The UE may be configured to use either feedback resource 1 of PUCCH928at slot 3 or feedback resource 2 of PUCCH929at slot 4 to provide ACK/NACK responses for the downlink transmission Rx 1 of PDSCH922and the downlink transmission Rx 2 of PDSCH926.

The UE may be similarly configured to use a type 1, or a static CB, shown to the right of PUCCH928and PUCCH929of CC1920, similar to the CB used for the ACK/NACK response of PUCCH828of CC1820inFIG.8.

At slot 0, the CC2may receive a PDCCH931which may carry a first DCI (DCI 1) that schedules a downlink transmission (Rx 1) illustrated as PDSCH932. At slot 1, the CC2may be transmitted a PDCCH933which may carry a second DCI (DCI 2) that schedules a downlink transmission (Rx 2) illustrated as PDSCH934. At slot 2, the CC2may receive a PDCCH935which may carry a third DCI (DCI 3) that schedules a downlink transmission (Rx 3) illustrated as PDSCH936. The DCI 1, DCI 2, and DCI 3 of the PDCCH931, PDCCH933, and PDCCH935, respectively, may also indicate a plurality of feedback resources—feedback resource 1 at PUCCH938and feedback resource 2 at PUCCH939—that the UE may use to transmit ACK/NACK responses for each TB received by the UE. The UE may be configured to use either feedback resource 1 of PUCCH938at slot 3 or feedback resource 2 of PUCCH939at slot 4 to provide ACK/NACK responses for the downlink transmission Rx 1 of PDSCH932, the downlink transmission Rx 2 of PDSCH934, and the downlink transmission Rx 3 of PDSCH936.

The UE may be similarly configured to use a type 1, or a static CB, shown to the right of PUCCH938and PUCCH939of CC2930, similar to the CB used of PUCCH838of CC2830inFIG.8.

In one aspect, the UE may be configured to indicate a pending status for any ACK/NACK response occasions before it finishes the corresponding PDSCH decoding. For example, if the UE has not finished decoding the downlink transmission Rx 1 of PDSCH922and the downlink transmission Rx 2 of PDSCH926before slot 3, the UE may be configured to transmit a pending status using the scheduled feedback resource 1 of PUCCH928. Similarly, if the UE has not finished decoding the downlink transmission Rx 1 of PDSCH932, the downlink transmission Rx 2 of PDSCH934, and the downlink transmission Rx 3 of PDSCH936before slot 3, the UE may be configured to transmit a pending status using the scheduled feedback resource 1 of PUCCH938. The UE may be configured to indicate a pending status to a network entity in any suitable manner.

In one aspect, the UE may be configured to report a NACK to the network entity when the status is pending. For the scheduled feedback resource 1 of PUCCH928, such a response may be 000000000000 or [0000][0000][0000]. For the scheduled feedback resource 1 of PUCCH938, such a response may be 000 or [0][0][0]. Such a configuration is simple to program and uses less power, but may introduce longer latency to report an actual NACK for some aspects as the network entity may be configured to wait for an ACK/NACK response to be transmitted during the last scheduled feedback resource to determine whether a previous NACK indicates a pending status or indicates a true NACK that should trigger a retransmission. A true NACK may occur if the UE finishes decoding early but fails to successfully decode any received transmissions, or if a UE misses all the scheduled DCIs of associated transmissions. Later, in response to the UE finishing decoding the PDSCH922and the PDSCH926of CC1920, the UE may be configured to transmit an ACK/NACK response using the scheduled feedback resource 2 of PUCCH929with 001100001100, or [0011][0000][1100]. Likewise, in response to the UE finishing decoding the PDSCH932and the PDSCH936of CC2930, the UE may be configured to transmit an ACK/NACK response using the scheduled feedback resource 2 of PUCCH939with 101, or [1][0][1].

FIG.10is a diagram1000illustrating an alternative example of a transmission feedback scenario, having slots1010, CC11020, PDCCH1021, PDSCH1022, NS1024, PDCCH1025, PDSCH1026, CC21030, PDCCH1031, PDSCH1032, PDCCH1033, PDSCH1034, PDCCH1035, and PDSCH1036similar to slots910, CC1920, PDCCH921, PDSCH922, NS924, PDCCH925, PDSCH926, CC2930, PDCCH931, PDSCH932, PDCCH933, PDSCH934, PDCCH935, and PDSCH936, respectively ofFIG.9.

In the diagram1000, the UE, such as the UE104inFIG.1orFIG.4, or the UE702inFIG.7, may be configured to have one or more additional bit in an ACK/NACK codebook to indicate a pending status. The UE may receive transmissions from a network entity, such as BS102or180inFIG.1or4, or network entity704inFIG.7. The UE may configure CC11020as having a maximum of five bits per TTI-one bit per CBG and one bit to indicate a pending status. A 1 for the pending status bit may be used to indicate that the UE has finished decoding and the subsequent bits may be used to indicate whether there is a decoding failure for each CBG. In another aspect, a 0 for the pending status bit may be used to indicate that the UE has not finished decoding and is in a pending status, and the subsequent bits may be reserved or may be used to indicate other status conditions. For the scheduled feedback resource 1 of PUCCH1028, such a pending status response may be 000000000000000 or [00000][00000][00000]. Later, in response to the UE finishing decoding the PDSCH1022and the PDSCH1026of CC11020, the UE may be configured to transmit an ACK/NACK response using the scheduled feedback resource 2 of PUCCH1029with 100111000011100, or [10011][10000][11100].

In another aspect the UE may configure CC11020as having a codebook having a pending status bit and three sets of codebook ACK/NACK responses each having four bits per TTI-one bit per CBG. Similarly, a 1 for the pending status bit may be used to indicate that the UE has finished decoding and the subsequent bits may be used to indicate whether there is a decoding failure for each CB G. In another aspect, a 0 for the pending status bit may be used to indicate that the UE has not finished decoding and is in a pending status, and the subsequent bits may be reserved or may be used to indicate other status conditions. For the scheduled feedback resource 1 of PUCCH1038, such a response may be 000000 or [00][00][00]. Later, in response to the UE finishing decoding the PDSCH1032, the PDSCH1034, and the PDSCH1036of CC21030, the UE may be configured to transmit an ACK/NACK response using the scheduled feedback resource 2 of PUCCH1039with 111011, or [11][10][11].

FIG.11is a diagram1100illustrating an alternative example of a transmission feedback scenario, having slots1110, CC11120, PDCCH1121, PDSCH1122, NS1124, PDCCH1125, PDSCH1126, CC21130, PDCCH1131, PDSCH1132, PDCCH1133, PDSCH1134, PDCCH1135, and PDSCH1136similar to slots910, CC1920, PDCCH921, PDSCH922, NS924, PDCCH925, PDSCH926, CC2930, PDCCH931, PDSCH932, PDCCH933, PDSCH934, PDCCH935, and PDSCH936, respectively ofFIG.9.

In the diagram1100, the UE, such as UE104inFIGS.1and4or UE702inFIG.7, may be configured to have one or more additional bit in an ACK/NACK codebook to indicate a pending status. The UE may receive transmissions from a network entity, such as BS102or180inFIG.1or4, or network entity704inFIG.7. The UE may configure CC11120as having a maximum of five bits per TTI-one bit per CBG and one bit to indicate a pending status. A 1 for the pending status bit may be used to indicate that the UE has finished decoding and the subsequent bits may be used to indicate whether there is a decoding failure for each CBG. In another aspect, a 0 for the pending status bit may be used to indicate that the UE has not finished decoding and is in a pending status, and the subsequent bits may be reserved or may be used to indicate other status conditions. For the scheduled feedback resource 1 of PUCCH1128, such a pending status response may be 0000000000000 or [0][0000][0000][0000]. Later, in response to the UE finishing decoding the PDSCH1122and the PDSCH1126of CC11120, the UE may be configured to transmit an ACK/NACK response using the scheduled feedback resource 2 of PUCCH1129with 1001100001100, or [1][0011][0000][1100].

In another aspect, the UE may configure CC21130as having a maximum of two bits per TB or TTI—one bit per TB and one bit to indicate a pending status. A 1 for the pending status bit may be used to indicate that the UE has finished decoding and the other bit may be used to indicate whether there is a decoding failure for each TB. In another aspect, a 0 for the pending status bit may be used to indicate that the UE has not finished decoding and is in a pending status, and the other bit may be reserved or may be used to indicate other status conditions. In another aspect, 00 may be used for NACK, 11 may be used for ACK,01may be used to indicate a pending status, and 10 may be used as a reserved index or may be used to indicate a missed DCI for each CBG. For the scheduled feedback resource 1 of PUCCH1138, such a response may be 0000 or [0][0][0][0]. Later, in response to the UE finishing decoding the PDSCH1132, the PDSCH1134, and the PDSCH1136of CC21130, the UE may be configured to transmit an ACK/NACK response using the scheduled feedback resource 2 of PUCCH1139with 101, or [1][1][0][1].

FIG.12shows a diagram1200illustrating an example of a transmission feedback scenario for CC11220and CC21230of a UE, such as UE104inFIGS.1and4or UE702inFIG.7, configured to use a CB type 2. The UE may receive transmissions from a network entity, such as BS102or180inFIG.1or4, or network entity704inFIG.7. CC11220has a single ACK/NACK feedback resource at PUCCH1228and CC21230has a single ACK/NACK feedback resource at PUCCH1238. The slots1210show the slot timing for the transmission feedback scenario in diagram1200from slot 0 to slot 5. At slot 0, the CC1may receive a PDCCH1221which may carry a first DCI (DCI 1) that schedules a downlink transmission (Rx 1) illustrated as PDSCH1222. At slot 1 the network entity may not have scheduled any activity for the UE, providing not scheduled (NS)1224slot. At slot 2, the CC1may receive a PDCCH1225which may carry a second DCI (DCI 2) that schedules a downlink transmission (Rx 2) illustrated as PDSCH1226. The DCI 1 and the DCI 2 of the PDCCH1221and PDCCH1225, respectively, may also indicate a feedback resource of PUCCH1228at slot 3 that the UE may use to transmit ACK/NACK responses for each codebook group (CBG) received by the UE.

At slot 0, the CC2may receive a PDCCH1231which may carry a first DCI (DCI 1) that schedules a downlink transmission (Rx 1) illustrated as PDSCH1232. At slot 1, the CC2may be transmitted a PDCCH1233which may carry a second DCI (DCI 2) that schedules a downlink transmission (Rx 2) illustrated as PDSCH1234. At slot 2, the CC2may receive a PDCCH1235which may carry a third DCI (DCI 3) that schedules a downlink transmission (Rx 3) illustrated as PDSCH1236. The DCI 1, DCI 2, and DCI 3 of the PDCCH1231, PDCCH1233, and PDCCH1235, respectively, may also indicate a feedback resource of PUCCH1238at slot 3 that the UE may use to transmit a ACK/NACK responses for each TB received by the UE.

The UE may be configured to use a type 2, or a dynamic CB, which may alter the size of the CB depending on the number of scheduled transmissions. For example, the CB for the ACK/NACK response of PUCCH1228may be configured to be two CBs, as the network entity only scheduled two associated PDSCHs for CC11220during slots 0 to 2. This differs from the ACK/NACK response of PUCCH828ofFIG.8which has three CBs, as the UE is unable to confirm that the network entity only scheduled two associated PDSCHs for CC1820during slots 0 to 2. As such, the UE may be configured to only transmit CBs for ACK/NACK responses of actual scheduled transmissions, as opposed to the NACK 0000 response transmitted for the unscheduled NS824inFIG.8using the ACK/NACK feedback resource of PUCCH828. A network entity may be configured to transmit at least one downlink assignment index (DAI) with each DCI to help the UE identify an unscheduled PDSCH. The DAI may correspond to a field/sub-field in the scheduling DCI, and may indicate a count of how many PDSCH scheduling that the UE should ACK/NACK in the same ACK/NACK occasion. For example, the scheduling DCI 1 of PDCCH1221for CC11220, DCI 2 of PDCCH1225for CC11220, DCI 1 of PDCCH1231for CC21230, DCI2 of PDCCH1233for CC21230, and DCI 3 of PDCCH1235for CC21230each may be configured to have a DAI field/sub-field that corresponds with two counters—a total DAI (tDAI) and a counter DAI (cDAI). The tDAI and cDAI transmitted by the network entity may be used by a UE to determine if a DCI for a CC has been missed. The network entity may be configured to provide multiple DAI counter values for a DCI, such as the cDAI value and the tDAI value of DCI 1 of PDCCH1221.

For example, in diagram1200, the network entity may transmit the DCI 1 of PDCCH1221for CC11220. The network entity may set the cDAI to 1 as the first DCI of CC1and the tDAI to 1 as the first associated DCI. The network entity may also transmit the DCI 1 of PDCCH1231for CC21230. The network entity may set the cDAI to 1 as the first DCI of CC2and the tDAI to 2 as the second associated DCI. The network entity may also transmit the DCI 2 of PDCCH1233for CC21230. The network entity may set the cDAI to 2 as the second DCI of CC2and the tDAI to 3 as the third associated DCI. The network entity may also transmit the DCI 2 of PDCCH1225for CC11220. The network entity may set the cDAI to 2 as the second DCI of CC1and the tDAI to 4 as the fourth associated DCI. The network entity may also transmit the DCI 3 of PDCCH1235for CC21230. The network entity may set the cDAI to 3 as the third DCI of CC2and the tDAI to 5 as the fifth associated DCI. The UE may use the DAI counters to determine that the network entity did not schedule a download transfer PDSCH between the PDSCH1222and the PDSCH1226, and may also use the DAI counters to determine that the ACK/NACK response should contain only two TTIs of 4 CBGs, as only two TTIs were scheduled by the network entity.

As previously explained, different PDSCH decoding schemes may require different decoding times, and only providing a single feedback resource per group of PDSCH downlink transmissions may introduce needless delays or decoding failures.FIG.13is a diagram1300illustrating an alternative example of a transmission feedback scenario for a CC11320and CC21330of a UE, such as UE104inFIGS.1and4or UE702inFIG.7, configured to use a dynamic CB type 2. The UE may receive transmissions from a network entity, such as BS102or180inFIG.1or4, or network entity704inFIG.7. CC11320has multiple ACK/NACK feedback resources, ACK/NACK feedback resource 1 at PUCCH1328and ACK/NACK feedback resource 2 at PUCCH1329. CC21330also has multiple ACK/NACK feedback resources, ACK/NACK feedback resource 1 at PUCCH1338and ACK/NACK feedback resource 2 at PUCCH1339.

The slots1310show the slot timing for the transmission feedback scenario in diagram1300from slot 0 to slot 5. At slot 0, the CC1may similarly receive a PDCCH1321which may carry a first DCI (DCI 1) that schedules a downlink transmission (Rx 1) illustrated as PDSCH1322. At slot 1, the network entity may not have scheduled any activity for the UE, providing not scheduled (NS)1324slot. At slot 2, the CC1may receive a PDCCH1325which may carry a second DCI (DCI 2) that schedules a downlink transmission (Rx 2) for the following three slots 9-11 illustrated as PDSCH1326. The DCI 1 and the DCI 2 of the PDCCH1321and PDCCH1325, respectively, may also indicate a plurality of feedback resources—feedback resource 1 at PUCCH1328and feedback resource 2 at PUCCH1329—that the UE may use to transmit ACK/NACK responses for each codebook group (CBG) received by the UE. The UE may be configured to use either feedback resource 1 of PUCCH1328at slot 3 or feedback resource 2 of PUCCH1329at slot 4 to provide ACK/NACK responses for the downlink transmission Rx 1 of PDSCH1322and the downlink transmission Rx 2 of PDSCH1326.

The UE may be similarly configured to use a type 2, or a dynamic CB, shown to the right of PUCCH1328and PUCCH1329of CC11320, similar to the CB used of PUCCH1228of CC11220inFIG.12.

At slot 0, the CC2may receive a PDCCH1331which may carry a first DCI (DCI 1) that schedules a downlink transmission (Rx 1) illustrated as PDSCH1332. At slot 1, the CC2may receive a PDCCH1333which may carry a second DCI (DCI 2) that schedules a downlink transmission (Rx 2) illustrated as PDSCH1334. At slot 2, the CC2may receive a PDCCH1335which may carry a third DCI (DCI 3) that schedules a downlink transmission (Rx 3) illustrated as PDSCH1336. The DCI 1, DCI 2, and DCI 3 of the PDCCH1331, PDCCH1333, and PDCCH1325, respectively, may also indicate a plurality of feedback resources—feedback resource 1 at PUCCH1338and feedback resource 2 at PUCCH1339—that the UE may use to transmit ACK/NACK responses for each TB received by the UE. The UE may be configured to use either feedback resource 1 of PUCCH1338at slot 3 or feedback resource 2 of PUCCH1339at slot 4 to provide ACK/NACK responses for the downlink transmission Rx 1 of PDSCH1332, the downlink transmission Rx 2 of PDSCH1334, and the downlink transmission Rx 3 of PDSCH1326.

The UE may be similarly configured to use a type 2, or a dynamic CB, shown to the right of PUCCH1338and PUCCH1339of CC21330, similar to the CB used of PUCCH1238of CC21230inFIG.12.

In one aspect, the UE may be configured to change its behavior for a subsequent PUCCH candidate based on whether the UE reported an ACK/NACK in an earlier PUCCH occasion. For example, a UE may be configured to skip the ACK/NACK bit for a PDSCH that has been reported in a previous PUCCH candidate. For example, here the UE may have decoded the PDSCH1322and the PDSCH1326using a decoding scheme associated with the earlier feedback resource 1 of PUCCH1328. The UE may have then transmitted, to the network entity, 00111100 or [0011][1100] using the feedback resource 1 of PUCCH1328. Later, the UE may be configured to skip transmitting an ACK/NACK response using the feedback resource 2 of PUCCH1329in response to determining that the UE already transmitted the ACK/NACK response earlier. Likewise, the UE may have decoded the PDSCH1332, the PDSCH1334, and the PDSCH1336using a decoding scheme associated with the earlier feedback resource 1 of PUCCH1338. The UE may have then transmitted, to the network entity,101or [1][0][1] using the feedback resource 1 of PUCCH1338. Later, the UE may be configured to skip transmitting an ACK/NACK response using the feedback resource 2 of PUCCH1339in response to determining that the UE already transmitted the ACK/NACK response earlier. Such a configuration saves power, but the previous ACK/NACK response transmitted using the feedback resource 1 of PUCCH1328or the feedback resource 1 of PUCCH1338may not have been received and/or may not have been correctly decoded by the network entity, which may cause a codebook size mismatch issue.

A UE may be configured to generate more than one HARQ codebook. Where a UE has at least two HARQ codebooks, the UE may be configured to associate each HARQ codebook with a different PUCCH PHY priority. The UE may be configured to ensure each codebook has its own dedicated PUCCH/PUSCH resource association. The UE may also be configured to generate and/or encode ACK/NACK bits in each codebook separately or independently.

FIG.14is a diagram1400illustrating an alternative example of a transmission feedback scenario, having slots1410, CC11420, PDCCH1421, PDSCH1422, NS1424, PDCCH1425, PDSCH1426, CC21430, PDCCH1431, PDSCH1432, PDCCH1433, PDSCH1434, PDCCH1435, and PDSCH1436similar to slots1310, CC11320, PDCCH1321, PDSCH1322, NS1324, PDCCH1325, PDSCH1326, CC21330, PDCCH1331, PDSCH1332, PDCCH1333, PDSCH1334, PDCCH1335, and PDSCH1336, respectively ofFIG.13. The DCI 1 and the DCI 2 of the PDCCH1421and PDCCH1425, respectively, may also indicate a plurality of feedback resources— feedback resource 1 of PUCCH1428at slot 3 and feedback resource 2 of PUCCH1329at slot 5—that the UE may use to transmit ACK/NACK responses for each codebook group (CBG) received by the UE. Similarly, the DCI 1, DCI 2, and DCI 3 of the PDCCH1431, PDCCH1433, and PDCCH1425, respectively, may also indicate a plurality of feedback resources—feedback resource 1 of PUCCH1438at slot 3 and feedback resource 2 of PUCCH1439at slot 5—that the UE may use to transmit ACK/NACK responses for each TB received by the UE.

In one aspect, the UE, such as UE104inFIGS.1and4or UE702inFIG.7, may be configured to change its behavior for a subsequent PUCCH candidate based on whether the UE reported an ACK/NACK in an earlier PUCCH occasion. The UE may receive transmissions from a network entity, such as BS102or180inFIG.1or4, or network entity704inFIG.7. The network entity may be configured to add another counter to the scheduling DCI to indicate how many ACK/NACK responses associated with the current PUCCH occasion have been received previously. The UE may use such counters to skip repetitive ACK/NACK responses in subsequent feedback resources. Here, the network entity may be configured to increment a counter feedback resource (cFR) for CC11420after the UE transmits an ACK/NACK response using the feedback resource 1 of PUCCH1428, and may be configured to increment a cFR for CC21430after the UE transmits an ACK/NACK response using the feedback resource 1 of PUCCH1438.

In diagram1400, in response to receiving the ACK/NACK response of [1111][1100] using PUCCH1428from the UE, the network entity may transmit the DCI 3 of PDCCH1441for CC11420to schedule the PDSCH1442. The network entity may set the cDAI to 3 as the third DCI of CC1, the tDAI to 6 as the sixth associated DCI, and the cFR to 1 as the first feedback resource has been used by the UE to transmit an ACK/NACK response for CC11420. Later, the UE may be configured to skip transmitting an ACK/NACK response using the feedback resource 2 of PUCCH1429in response to determining that the network entity already confirmed receipt of the ACK/NACK response for CC11420earlier by transmitting the updated cFR. Similarly, in response to receiving the ACK/NACK response of [1][1][1] using PUCCH1438from the UE, the network entity may transmit the DCI 4 of PDCCH1451for CC21430to schedule the PDSCH1452. The network entity may set the cDAI to 4 as the fourth DCI of CC2, the tDAI to 7 as the seventh associated DCI, and the cFR to 1 as the first feedback resource has been used by the UE to transmit an ACK/NACK response for CC21430. Later, the UE may be configured to skip transmitting an ACK/NACK response using the feedback resource 2 of PUCCH1439in response to determining that the network entity already confirmed receipt of the ACK/NACK response for CC21430earlier by transmitting the updated cFR.

For type 2 HARQ CBs, in response to determining that multiple ACK/NACK candidates are configured for a PDSCH, the network entity may be configured to use the scheduling DCI to indicate multiple DAI counter values, where each counter value may correspond with an ACK/NACK candidate occasion.

FIG.15is a diagram1500illustrating an alternative example of a transmission feedback scenario, having slots1510, CC11520, PDCCH1521, PDSCH1522, NS1524, PDCCH1525, PDSCH1526, CC21530, PDCCH1531, PDSCH1532, PDCCH1533, PDSCH1534, PDCCH1535, and PDSCH1536similar to slots1310, CC11320, PDCCH1321, PDSCH1322, NS1324, PDCCH1325, PDSCH1326, CC21330, PDCCH1331, PDSCH1332, PDCCH1333, PDSCH1334, PDCCH1335, and PDSCH1336, respectively ofFIG.13. The DCI 1 and the DCI 2 of the PDCCH1521and PDCCH1525, respectively, may also indicate a plurality of feedback resources-feedback resource 1 of PUCCH1528at slot 3 and feedback resource 2 of PUCCH1529at slot 5—that the UE may use to transmit ACK/NACK responses for each codebook group (CBG) received by the UE. Similarly, the DCI 1, DCI 2, and DCI 3 of the PDCCH1531, PDCCH1533, and PDCCH1525, respectively, may also indicate a plurality of feedback resources-feedback resource 1 of PUCCH1538at slot 3 and feedback resource 2 of PUCCH1539at slot 5—that the UE may use to transmit ACK/NACK responses for each TB received by the UE.

In one aspect, the UE, such as UE104inFIGS.1and4or UE702inFIG.7, may be configured to repeat an ACK/NACK response using subsequent feedback resources until the UE receives a DCI that schedules a new transmission or a retransmission of the same HARQ_ID. The UE may receive transmissions from a network entity, such as BS102or180inFIG.1or4, or network entity704inFIG.7. The UE may transmit an ACK using the feedback resource 1 of PUCCH1528, and the UE may then receive a DCI of PDCCH1541to schedule a new downlink transmission of PDSCH1542. Later, the UE may be configured to skip transmitting an ACK/NACK response using the feedback resource 2 of PUCCH1529in response to determining that the network entity impliedly confirmed receipt of the ACK response by scheduling a new transmission using PDCCH1541. In another aspect, the UE may transmit an ACK using the feedback resource 1 of PUCCH1538, and the UE may then receive a DCI of PDCCH1551to schedule a new downlink transmission of PDSCH1552. Later, the UE may be configured to skip transmitting an ACK/NACK response using the feedback resource 2 of PUCCH1539in response to determining that the network entity impliedly confirmed receipt of the ACK response by scheduling a new transmission.

In another aspect, the UE may transmit a NACK using the feedback resource 1 of PUCCH1528, and the UE may then receive a DCI of PDCCH1541to schedule a retransmission of PDSCH1522using PDSCH1542. Later, the UE may be configured to skip transmitting an ACK/NACK response using the feedback resource 2 of PUCCH1529in response to determining that the network entity impliedly confirmed receipt of the NACK by scheduling a retransmission using PDCCH1551. In another aspect, the UE may transmit a NACK using the feedback resource 1 of PUCCH1538, and the UE may then receive a DCI of PDCCH1551to schedule a retransmission of PDSCH1532using PDSCH1552. Later, the UE may be configured to skip transmitting an ACK/NACK response using the feedback resource 2 of PUCCH1539in response to determining that the network entity impliedly confirmed receipt of the NACK response by scheduling a new transmission.

FIG.16is a diagram1600illustrating an alternative example of a transmission feedback scenario, having slots1610, CC11620, PDCCH1621, PDSCH1622, NS1624, PDCCH1625, PDSCH1626, CC21630, PDCCH1631, PDSCH1632, PDCCH1633, PDSCH1634, PDCCH1635, and PDSCH1636similar to slots1310, CC11320, PDCCH1321, PDSCH1322, NS1324, PDCCH1325, PDSCH1326, CC21330, PDCCH1331, PDSCH1332, PDCCH1333, PDSCH1334, PDCCH1335, and PDSCH1336, respectively ofFIG.13. The DCI 1 and the DCI 2 of the PDCCH1621and PDCCH1625, respectively, may also indicate a plurality of feedback resources-feedback resource 1 of PUCCH1628at slot 3 and feedback resource 2 of PUCCH1629at slot 4—that the UE may use to transmit ACK/NACK responses for each codebook group (CBG) received by the UE. Similarly, the DCI 1, DCI 2, and DCI 3 of the PDCCH1631, PDCCH1633, and PDCCH1625, respectively, may also indicate a plurality of feedback resources-feedback resource 1 of PUCCH1638at slot 3 and feedback resource 2 of PUCCH1639at slot 4—that the UE may use to transmit ACK/NACK responses for each TB received by the UE.

In one aspect, the UE, such as UE104inFIGS.1and4or UE702inFIG.7, may be configured to repeat an ACK/NACK response using subsequent feedback resources to provide redundancy. The UE may receive transmissions from a network entity, such as BS102or180inFIG.1or4, or network entity704inFIG.7. The UE may transmit an ACK/NACK response using the feedback resource 1 of PUCCH1628, and may later retransmit transmit the ACK/NACK response using the feedback resource 2 of PUCCH1629. In another aspect, the UE may transmit an ACK/NACK response using the feedback resource 1 of PUCCH1638, and may later retransmit transmit the ACK/NACK response using the feedback resource 2 of PUCCH1639. Such a configuration may provide stability, but may also require more overhead as the UE may provide redundant ACK/NACK responses.

FIG.17is a diagram1700illustrating an alternative example of a transmission feedback scenario, having slots1710, CC11720, PDCCH1721, PDSCH1722, NS1724, PDCCH1725, PDSCH1726, PUCCH1728, and PUCCH1729similar to slots1010, CC11020, PDCCH1021, PDSCH1022, NS1024, PDCCH1025, PDSCH1026, PUCCH1028, and PUCCH1029, respectively ofFIG.9. Diagram1700also has CC21730, PDCCH1731, PDSCH1732, NS1734, PDCCH1735, PDSCH1736, and PUCCH1738similar to CC2830, PDCCH831, PDSCH832, PDCCH833, PDSCH834, PDCCH835, PDSCH836, and PUCCH838, respectively ofFIG.8.

In the diagram1700, the UE, such as UE104inFIGS.1and4or UE702inFIG.7, may be configured to have one or more additional bit in an ACK/NACK codebook for CC11720to indicate a pending status. The UE may receive transmissions from a network entity, such as BS102or180inFIG.1or4, or network entity704inFIG.7. The UE may configure CC11020as having a maximum of five bits per TTI-one bit per CBG and one bit to indicate a pending status. A 1 for the pending status bit may be used to indicate that the UE has finished decoding and the subsequent bits may be used to indicate whether there is a decoding failure for each CBG. In another aspect, a 0 for the pending status bit may be used to indicate that the UE has not finished decoding and is in a pending status, and the subsequent bits may be reserved or may be used to indicate other status conditions. For the scheduled feedback resource 1 of PUCCH1028, such a pending status response may be 000000000000000 or [00000][00000][00000]. Later, in response to the UE finishing decoding the PDSCH1022and the PDSCH1026of CC11020, the UE may be configured to transmit an ACK/NACK response using the scheduled feedback resource 2 of PUCCH1029of 100111000011100, or [10011][10000][11100].

The UE may also be configured to have no additional bit for CC21730to indicate a pending status. In other words, the codebook for CC21730may be configured to only use a single feedback resource for a set of associated PDSCH downlink transmissions, such as PDSCH1732and PDSCH1736. The codebook for CC21730does not need a pending status as the codebook for CC11720does, as only one feedback resource may be scheduled for a set of associated PDSCH downlink transmissions. The UE may use the same decoding scheme to decode each of the PDSCH's1722,1726,1732, and1736, or may use different decoding schemes based upon trigger conditions.

In one aspect, the PUCCH resources for both codebooks may be overlapped, allowing for a UE to be configured to use a PUCCH resource for both codebooks. The UE may be configured to generate and/or encode the bits of the ACK/NACK response, and then multiplex the bits in the PUCCH. A network entity may be configured to de-multiplex the transmitted bits to separate the codebooks. The UE may be configured to select a HARQ codebook based on a scheduling DCI or a preconfiguration in a PUCCH resource. For example, the UE may be configured to determine that the scheduling DCI has only scheduled a single feedback resource for a set of associated PDSCH downlink transmissions, and in response may select the codebook for CC2having a single feedback resource for a set of associated PDSCH downlink transmissions and no additional bit to indicate a pending status. In another aspect, the UE may be configured to determine a conditional trigger exists that allows the UE to use a plurality of decoding schemes to decode a downlink transmission, and in response may select the codebook for CC11720having a plurality of feedback resources for a set of associated PDSCH downlink transmissions and an additional bit to indicate a pending status.

FIG.18is a diagram1800illustrating an alternative example of a transmission feedback scenario for a CC1820of a UE, such as UE104inFIG.1. The slots1810show the slot timing for the transmission feedback scenario from slot 0 to slot 6. At slot 0, the CC1820may receive a PDCCH1822which may carry DCI that schedules a downlink transmission illustrated as PDSCH1824and may indicate a feedback resource 1-1 illustrated as PUCCH1825at slot 2 and a feedback resource 1-2 illustrated as PUCCH1826at slot 4. At slot 1, the CC1820may receive a PDCCH1832which may carry DCI that schedules a downlink transmission illustrated as PDSCH1834and may indicate a feedback resource 2-1 illustrated as PUCCH1835at slot 3, a feedback resource 2-2 illustrated as PUCCH1836at slot 5, and a feedback resource 2-3 illustrated as PUCCH1837at slot 6.

A network entity may be configured to follow an out of order rule (000) to schedule feedback resources for a plurality of scheduled PDSCH transmissions. For example, a network entity may be configured to ensure that a scheduled feedback resource for an ACK/NACK response in a later slot cannot proceed a scheduled feedback resource for an ACK/NACK response in an earlier slot. The 000 rule may also allow an ACK/NACK response for two PDSCH transmissions to occur within the same slot. For example, a UE using an 000 rule may be configured to schedule a PUCCH transmission for both PDSCH1824and PDSCH1834for slot 4 (e.g. a first PUCCH during the last 2 symbols of slot 4 and a second PUCCH during the second to last 2 symbols of slot 4). The UE, such as UE104inFIGS.1and4or UE702inFIG.7, may be configured to relax the 000 rule when a PDSCH has multiple ACK/NACK feedback resources. The UE may receive transmissions from a network entity, such as BS102or180inFIG.1, CU410, DU430, or RU440inFIG.4, or network entity704inFIG.7. Relaxing the 000 rule allows a network entity to schedule the feedback resource 1-2 of PUCCH1826at slot 5 to be later than the feedback resource 2-2 of PUCCH1836at slot 4. Here, the UE may have selected a decoding scheme associated with the feedback resource 1-2 of PUCCH1826at slot 15 to decode the downlink transmission data of PDSCH1824. The UE may have also selected a decoding scheme associated with the feedback resource 2-1 of PUCCH1835at slot 11 to decode the downlink transmission data of PDSCH1834. Ensuring that a network entity follows the 000 rule may cause later-received PDSCH downlink transmissions to have delayed ACK/NACK responses.

The UE may also be configured to not allow transmission of a feedback resource that has a k-th ACK/NACK occasion for an earlier PDSCH later than the k-th ACK/NACK occasion for a later PDSCH. In other words, a network entity may be configured to not schedules the 2ndor 3rdfeedback resource 2-2 or 2-3 of PDSCH1834to be earlier than the 2ndfeedback resource 1-2 of PDSCH1824.

FIG.19is a flowchart1900of a method of wireless communication. The method may be performed by a UE (e.g., the UE104; the UE702; the apparatus2602). At1902, the UE may receive, from a network entity, control information scheduling a downlink transmission and indicating a first feedback resource for a first decoding scheme of the UE and a second feedback resource for a second decoding scheme of the UE. For example,902may be performed by the UE702inFIG.7which may receive a transmission from the network entity704, in a transmission716, having control information scheduling downlink transmission and indicating multiple feedback resources. The multiple feedback resources could be a first feedback resource 1 of PUCCH636inFIG.6for a first decoding scheme of the UE, such as an MMSE decoding scheme, and a second feedback resource 2 of PUCCH638for a second decoding scheme of the UE, such as an NL decoding scheme. Further,1902may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At1904, the UE may receive, from the network entity, a downlink transmission. For example,1904may be performed by the UE702inFIG.7that may receive, from the network entity704, a downlink transmission718. Further,1904may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At1906, the UE may decode the downlink transmission using at least one of the first decoding scheme or the second decoding scheme. For example,1906may be performed by the UE702inFIG.7that decodes at726the downlink transmission using a demodulation scheme, which may be an MMSE decoding scheme or an NL decoding scheme. Further,902may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At1908, the UE may transmit, to the network entity, a first ACK/NACK response based on the decoded downlink transmission using the first feedback resource if decoding the downlink transmission using the first decoding scheme or using the second feedback resource if decoding the downlink transmission using the second decoding scheme. For example,1908may be performed by the UE702inFIG.7, which may transmit an ACK/NACK response720using one of the multiple feedback resources. The multiple feedback resources could be a first feedback resource 1 of PUCCH636inFIG.6for a first decoding scheme of the UE, such as an MMSE decoding scheme, and a second feedback resource 2 of PUCCH638for a second decoding scheme of the UE, such as an NL decoding scheme. Further, 1908 may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

FIG.20is a flowchart2000of a method of wireless communication. The method may be performed by a UE (e.g., the UE104; the UE702; the apparatus2602). At2002, the UE may transmit, to the network entity, an indication that the UE supports receiving a plurality of feedback resources for the downlink transmission. For example,2002may be performed by the UE702inFIG.7, which may transmit, to the network entity704, an indication in a transmission712that the UE702supports receiving a plurality of feedback resources for the downlink transmission718transmitted from the network entity704to the UE702. Further,2002may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2004, the UE may receive, from the network entity, signaling that enables a configuration of the plurality of feedback resources for a PDSCH. For example,2004may be performed by the UE702which may receive, from the network entity704, signaling that enables a configuration of the plurality of feedback resources for a PDSCH. Further,902may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2006, the UE may transmit, to the network entity, timing information including a first minimum K1 value associated with the first decoding scheme and a second minimum K1 value associated with the second decoding scheme. For example,2006may be performed by the UE702inFIG.7that transmits timing information in a transmission714, where the timing information includes a first minimum K1 value associated with a first decoding scheme, such as an MMSC decoding scheme, and a second minimum K1 value associated with the second decoding scheme, such as an NL decoding scheme. Further,2006may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2008, the UE may receive, from the network entity, a plurality of K1 values, where the control information scheduling the downlink transmission indicates at least two K1 values from the plurality of K1 values. For example,2008may be performed by the UE702inFIG.7that may receive, from the network entity704, a plurality of K1 values via a transmission714of timing information of minimum K1 values associated with decoding schemes. The transmitted control information, in a transmission716, scheduling downlink information may indicate at least two K1 values from the plurality of K1 values. For example, the network entity704may be configured to transmit a DCI in a transmission716to the UE702that selects a plurality of K1 values. Further,2008may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2010, the UE may transmit, to the network entity, a first conditional trigger associated with the first decoding scheme, where decoding the downlink transmission using at least one of the first decoding scheme or the second decoding scheme may include decoding the downlink transmission using the first decoding scheme if one or more environmental conditions satisfies the first conditional trigger. For example,2010may be performed by the UE702inFIG.7that may transmit a conditional trigger associated with the first decoding scheme in a transmission712, which may be a MMSE decoding scheme. The UE may decode the downlink transmission using the MMSE decoding scheme if one or more environmental conditions satisfies the first conditional trigger, such as an MCS value, a rank value, a battery level of the UE, or channel statistics derived from channel measurements. Further,2010may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2012, the UE may transmit, to the network entity, an indicator that the first ACK/NACK response using the second feedback resource is pending using the first feedback resource. For example,2012may be performed by the UE702inFIG.7to transmit, to the network entity704, and indicator, such as the ACK/NACK response using feedback resource 1 of PUCCH1028inFIG.10having a pending status bit. The pending status bit using the feedback resource 1 of PUCCH1028indicates that the ACK/NACK response using the feedback resource 2 of PUCCH1029is pending. Further,2012may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2014, the UE may generate a multiplexed ACK/NACK response by multiplexing the first ACK/NACK response or the second ACK/NACK response based on the first HARQ codebook and a third ACK/NACK response based on the second HARQ codebook, where transmitting, to the network entity, the first ACK/NACK response may include transmitting the multiplexed ACK/NACK response. For example,2014may be performed by the UE702inFIG.7, which may generate a multiplexed ACK/NACK response by multiplexing a first ACK/NACK response, such as the ACK/NACK response transmitted using feedback resource 1 of PUCCH1728, or a second ACK/NACK response, such as the ACK/NACK response transmitted using feedback resource 2 of PUCCH1729, based on the codebook of CC11720, and a third ACK/NACK response, such as the ACK/NACK response transmitted using the feedback resource of PUCCH1738based on the codebook of CC21730. The UE702inFIG.7may transmit such a multiplexed ACK/NACK response to the network entity704. Further,902may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

FIG.21is a flowchart2100of a method of wireless communication. The method may be performed by a UE (e.g., the UE104; the UE702; the apparatus2602). At2102, the UE may receive, from the network entity, a second downlink transmission having a single feedback resource. For example,2102may be performed by the UE702inFIG.7that may receive, from the network entity704, a second downlink transmission, such as the PDSCH1732inFIG.17, having a single feedback resource of PUCCH1738. Further,2102may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2104, the UE may decode the second downlink transmission using the first decoding scheme. For example,2104may be performed by the UE702inFIG.7that may decode the second downlink transmission of PDSCH1732using the same decoding scheme that is used to decode the downlink transmission of PDSCH1722. Further,2104may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2106, the UE may transmit, to the network entity, a third ACK/NACK response for the decoded second downlink transmission using the single feedback resource. For example,2106may be performed by the UE702inFIG.7that may transmit, to the network entity704, a third ACK/NACK response, such as the ACK/NACK response for the decoding of the PDSCH1732using the feedback resource of PUCCH1738. Further,2106may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2108, the UE may receive, from the network entity, a scheduling DCI may include a counter of ACK/NACK responses. For example,2108may be performed by the UE702inFIG.7receiving, from the network entity704, a scheduling DCI that may include a counter of ACT/NACK responses, such as the cFR in the DCI 3 of PDCCH1441inFIG.14. Further,2108may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2110, the UE may determine whether to retransmit, to the network entity, the first ACK/NACK response using the second feedback resource after transmitting the first ACK/NACK response using the first feedback resource if the counter of ACK/NACK responses does not meet or exceed a threshold value. For example,2110may be performed by the UE702inFIG.7that may determine whether to retransmit, to the network entity704, the first ACK/NACK response using the ACK/NACK feedback resource 2 of PUCCH1429inFIG.14that was previously transmitted using the ACK/NACK feedback resource 1 of PUCCH1428if the counter cFR of ACK/NACK responses in the DCI of PDCCH1441does not meet or exceed the threshold value of 1. Further,2110may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

FIG.22is a flowchart2200of a method of wireless communication. The method may be performed by a UE (e.g., the UE104; the UE702; the apparatus2602). At2202, the UE may retransmit, to the network entity, the first ACK/NACK response using the second feedback resource after transmitting the first ACK/NACK response using the first feedback resource. For example,2202may be performed by the UE702inFIG.7that may retransmit, to the network entity704, the ACK/NACK response using feedback resource 2 of PUCCH1629that was previously transmitted using feedback resource 1 of PUCCH1628. Further,2202may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2204, the UE may receive, from the network entity, additional control information after transmitting, to the network entity, the first ACK/NACK response using the first feedback resource, the additional control information scheduling at least one of an additional downlink transmission or a retransmission of the downlink transmission. For example,2204may be performed by the UE702inFIG.7that may receive, from the network entity704, additional control information in the DCI 3 of PDCCH1541inFIG.15after transmitting, to the network entity704, the first ACK/NACK response using the feedback resource 1 of PUCCH1528. The additional control information in the DCI 3 of PDCCH1541inFIG.15may be an additional new downlink transmission or a retransmission of a previous downlink transmission, such as a retransmission of PDSCH1522using PDSCH1542. Further,2204may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

At2206, the UE may skip retransmission, to the network entity, of the first ACK/NACK response using the second feedback resource in response to receiving, from the network entity, the additional control information. For example,2206may be performed by the UE702inFIG.7that may skip retransmission, to the network entity704, of the first ACK/NACK response using the feedback resource 2 of PUCCH1529in response to receiving, from the network entity704, the additional control information in DCI 3 of PDCCH1541. Further,2206may be performed by the dynamic ACK/NACK transmission component2640inFIG.26.

FIG.23is a flowchart2300of a method of wireless communication. The method may be performed by a network entity (e.g., the base station102/180; the CU410, the DU430, the RU440, any combination of the CU410and DU430and RU440, the network entity704, the apparatus2702). The network entity or network node may be implemented as a base station (i.e., an aggregated base station), as a disaggregated base station, an IAB node, a relay node, a CU, a DU, a RU, a Near-RT RIC, or a Non-RT RIC in a disaggregated base station architecture, etc. At2302, the network entity may receive timing information for a user equipment (UE) indicating a first minimum K1 value associated with a first decoding scheme and a second minimum K1 value associated with a second decoding scheme. For example,2302may be performed by the network entity704inFIG.7that may receive timing information in a transmission714for the UE702indicating minimum K1 values associated with decoding schemes of the UE702. Further,2302may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

At2304, the network entity may transmit control information for a downlink transmission of the UE indicating a first feedback resource based on the first minimum K1 value and a second feedback resource based on the second minimum K1 value. For example,2304may be performed by the network entity704inFIG.7, which may transmit control information for downlink transmission of the UE702in a transmission716indicating a first feedback resource based on the first minimum K1 value, such as the ACK/NACK feedback resource 1 of PUCCH636and the ACK/NACK feedback resource 2 of PUCCH638. Further,902may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

At2306, the network entity may transmit the downlink transmission of the UE. For example,2306may be performed by the network entity704inFIG.7that may transmit the downlink transmission718of the UE702. Further,2306may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

At2308, the network entity may receive an ACK/NACK response for the downlink transmission using the first feedback resource or the second feedback resource. For example,2308may be performed by the network entity704inFIG.7that may receive an ACK/NACK response720for the downlink transmission718transmitted by the network entity704using one of the multiple feedback resources. Further,2318may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

FIG.24is a flowchart2400of a method of wireless communication. The method may be performed by a network entity (e.g., the base station102/180; the CU410, the DU430, the RU440, any combination of the CU410and DU430and RU440, the network entity704, the apparatus2702). The network entity or network node may be implemented as a base station (i.e., an aggregated base station), as a disaggregated base station, an IAB node, a relay node, a CU, a DU, a RU, a Near-RT RIC, or a Non-RT RIC in a disaggregated base station architecture, etc. At2402, the network entity may receive information that the UE supports receiving multiple feedback resources. For example,2402may be performed by the network entity704inFIG.7that may receive information in a transmission712that the UE702supports receiving multiple feedback resources. Further,2402may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

At2404, the network entity may enable indication of the first feedback resource and the second feedback resource for the UE. For example,2404may be performed by the network entity704inFIG.7that may enable indication of the first feedback resource and the second feedback resource for the UE702by transmitting control information, in a transmission716, indicating multiple feedback resources. Further,2404may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

At2406, the network entity may determine whether the ACK/NACK response will be received using the first feedback resource or the second feedback resource based on whether a conditional trigger is satisfied. For example,2406may be performed by the network entity704inFIG.7that may determine at725whether the ACK/NACK response will be received based upon conditions. Further,2406may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

At2408, the network entity may transmit a DCI for the UE including an incremented counter of ACK/NACK responses in response to receiving the ACK/NACK response. For example,2408may be performed by the network entity704inFIG.7, that may transmit control information, in a transmission716, as a DCI for the UE702. The DCI may include an incremented counter of ACK/NACK responses, such as the DCI 3 of PDCCH1441inFIG.14that increments the cFR after receiving an ACK/NACK response using feedback resource 1 of PUCCH1428. Further,2408may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

At2410, the network entity may transmit an additional downlink transmission after receiving the ACK/NACK response for the downlink transmission using the first feedback resource in response to determining that the ACK/NACK response includes an ACK, where the first feedback resource is temporally before the second feedback resource. For example,2410may be performed by the network entity704inFIG.7that may transmit an additional downlink transmission, such as PDSCH1442inFIG.14, after receiving an ACK using feedback resource 1 of PUCCH1428for the downlink transmission PDSCH1422. The feedback resource 1 of PUCCH1428is temporally before the feedback resource 2 of PUCCH1429. Further,2410may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

FIG.25is a flowchart2500of a method of wireless communication. The method may be performed by a network entity (e.g., the base station102/180; the CU410, the DU430, the RU440, any combination of the CU410and DU430and RU440, the network entity704, the apparatus2702). The network entity or network node may be implemented as a base station (i.e., an aggregated base station), as a disaggregated base station, an IAB node, a relay node, a CU, a DU, a RU, a Near-RT RIC, or a Non-RT RIC in a disaggregated base station architecture, etc. At2402, the network entity may retransmit the downlink transmission of the UE after receiving the ACK/NACK response for the downlink transmission using the first feedback resource in response to determining that the ACK/NACK response includes a NACK, where the first feedback resource is temporally before the second feedback resource. For example,2502may be performed by the network entity704inFIG.7that may retransmit the downlink transmission of PDSCH1622in response to determining that the ACK/NACK response transmitted using the feedback resource 1 of PUCCH1628includes a NACK. The feedback resource 1 of PUCCH1628is temporally before the feedback resource 2 of PUCCH1629. Further,902may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

At2504, the network entity may transmit, to the UE, a DCI includes a cDAI and a tDAI. For example,2504may be performed by the network entity704inFIG.7that may transmit, to the UE702, a DCI, such as the DCI 3 of PDCCH1441that includes a cDAI and a tDAI. Further,2504may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

At2506, the network entity may schedule an additional downlink transmission for the UE having a third feedback resource and a fourth feedback resource, the third feedback resource being temporally before the second feedback resource for the downlink transmission. For example,2506may be performed by network entity704inFIG.7, which may schedule an additional downlink transmission of PDSCH1834inFIG.18for the UE702having a feedback resource 2-1 of PUCCH1835and feedback resource 2-2 of PUCCH1836. The feedback resource 2-1 of PUCCH1835is temporally before the feedback resource 1-2 of PUCCH1826. Further,2506may be performed by the dynamic ACK/NACK reception component2740inFIG.27.

FIG.26is a diagram2600illustrating an example of a hardware implementation for an apparatus2602. The apparatus2602may be a UE, a component of a UE, or may implement UE functionality. In some aspects, the apparatus2602may include a cellular baseband processor2604(also referred to as a modem) coupled to a cellular RF transceiver2622. In some aspects, the apparatus2602may further include one or more subscriber identity modules (SIM) cards2620, an application processor2606coupled to a secure digital (SD) card2608and a screen2610, a Bluetooth module2612, a wireless local area network (WLAN) module2614, a Global Positioning System (GPS) module2616, or a power supply2618. The cellular baseband processor2604communicates through the cellular RF transceiver2622with the UE104and/or BS102/180. The cellular baseband processor2604may include a computer-readable medium/memory. The computer-readable medium/memory may be non-transitory. The cellular baseband processor2604is responsible for general processing, including the execution of software stored on the computer-readable medium/memory. The software, when executed by the cellular baseband processor2604, causes the cellular baseband processor2604to perform the various functions described supra. The computer-readable medium/memory may also be used for storing data that is manipulated by the cellular baseband processor2604when executing software. The cellular baseband processor2604further includes a reception component2630, a communication manager2632, and a transmission component2634. The communication manager2632includes the one or more illustrated components. The components within the communication manager2632may be stored in the computer-readable medium/memory and/or configured as hardware within the cellular baseband processor2604. The cellular baseband processor2604may be a component of the UE350and may include the memory360and/or at least one of the Tx processor368, the Rx processor356, and the controller/processor359. In one configuration, the apparatus2602may be a modem chip and include just the baseband processor2604, and in another configuration, the apparatus2602may be the entire UE (e.g., see UE350ofFIG.3) and include the additional modules of the apparatus2602.

The communication manager2632includes a dynamic ACK/NACK transmission component2640that is configured to transmit ACK/NACK responses using a plurality of feedback resources scheduled for a downlink transmission, e.g., as described in connection with step1908inFIG.19. The dynamic ACK/NACK transmission component2640may be within the cellular baseband processor _2604, the application processor _2606, or both the cellular baseband processor _2604and the application processor _2606.

The apparatus may include additional components that perform each of the blocks of the algorithm in the flowcharts ofFIGS.19-24. As such, each block in the flowcharts ofFIGS.19-24may be performed by a component and the apparatus may include one or more of those components. The components may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by a processor configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by a processor, or some combination thereof.

As shown, the apparatus2602may include a variety of components configured for various functions. In one configuration, the apparatus2602, and in particular the cellular baseband processor2604, includes means for receiving, from a network entity, control information scheduling a downlink transmission and indicating a first feedback resource for a first decoding scheme of the UE and a second feedback resource for a second decoding scheme of the UE, means for receiving, from the network entity, a downlink transmission, means for decoding the downlink transmission using at least one of the first decoding scheme or the second decoding scheme, means for transmitting, to the network entity, a first ACK/NACK response based on the decoded downlink transmission using the first feedback resource if decoding the downlink transmission using the first decoding scheme or using the second feedback resource if decoding the downlink transmission using the second decoding scheme, means for transmitting, to the network entity, an indication that the UE supports receiving a plurality of feedback resources for the downlink transmission, means for receiving, from the network entity, signaling that enables a configuration of the plurality of feedback resources for a PDSCH, means for transmitting, to the network entity, timing information including a first minimum K1 value associated with the first decoding scheme and a second minimum K1 value associated with the second decoding scheme, means for receiving, from the network entity, a plurality of K1 values, where the control information scheduling the downlink transmission indicates at least two K1 values from the plurality of K1 values, means for transmitting, to the network entity, a first conditional trigger associated with the first decoding scheme, where decoding the downlink transmission using at least one of the first decoding scheme or the second decoding scheme includes decoding the downlink transmission using the first decoding scheme if one or more environmental conditions satisfies the first conditional trigger, means for transmitting, to the network entity, an indicator that the first ACK/NACK response using the second feedback resource is pending using the first feedback resource, means for generating a multiplexed ACK/NACK response by multiplexing the first ACK/NACK response or the second ACK/NACK response based on the first HARQ codebook and a third ACK/NACK response based on the second HARQ codebook, where transmitting, to the network entity, the first ACK/NACK response includes transmitting the multiplexed ACK/NACK response, means for receiving, from the network entity, a second downlink transmission having a single feedback resource, means for decoding the second downlink transmission using the first decoding scheme, means for transmitting, to the network entity, a third ACK/NACK response for the decoded second downlink transmission using the single feedback resource, means for receiving, from the network entity, a scheduling DCI including a counter of ACK/NACK responses, means for determining whether to retransmit, to the network entity, the first ACK/NACK response using the second feedback resource after transmitting the first ACK/NACK response using the first feedback resource if the counter of ACK/NACK responses does not meet or exceed a threshold value, means for retransmitting, to the network entity, the first ACK/NACK response using the second feedback resource after transmitting the first ACK/NACK response using the first feedback resource, means for receiving, from the network entity, additional control information after transmitting, to the network entity, the first ACK/NACK response using the first feedback resource, the additional control information scheduling at least one of an additional downlink transmission or a retransmission of the downlink transmission, and means for skipping retransmission, to the network entity, of the first ACK/NACK response using the second feedback resource in response to receiving, from the network entity, the additional control information. The means may be one or more of the components of the apparatus2602configured to perform the functions recited by the means. As described supra, the apparatus2602may include the Tx processor368, the Rx processor356, and the controller/processor359. As such, in one configuration, the means may be the Tx processor368, the Rx processor356, and the controller/processor359configured to perform the functions recited by the means.

FIG.27is a diagram2700illustrating an example of a hardware implementation for an apparatus2702. The apparatus2702may be a base station, a component of a base station, or may implement base station functionality. The apparatus2702may be implemented as a base station (i.e., an aggregated base station), as a disaggregated base station, an IAB node, a relay node, a CU, a DU, a RU, a Near-RT RIC, or a Non-RT RIC in a disaggregated base station architecture, etc. In some aspects, the apparatus2602may include a baseband unit2704. The baseband unit2704may communicate through a cellular RF transceiver2722with the UE104. The baseband unit2704may include a computer-readable medium/memory. The baseband unit2704is responsible for general processing, including the execution of software stored on the computer-readable medium/memory. The software, when executed by the baseband unit2704, causes the baseband unit2704to perform the various functions described supra. The computer-readable medium/memory may also be used for storing data that is manipulated by the baseband unit2704when executing software. The baseband unit2704further includes a reception component2730, a communication manager2732, and a transmission component2734. The communication manager2732includes the one or more illustrated components. The components within the communication manager2732may be stored in the computer-readable medium/memory and/or configured as hardware within the baseband unit2704. The baseband unit2704may be a component of the base station310and may include the memory376and/or at least one of the Tx processor316, the Rx processor370, and the controller/processor375.

The communication manager2732includes a dynamic ACK/NACK reception component2740that receives ACK/NACK responses for a downlink transmission using a plurality of feedback resources, e.g., as described in connection with2302inFIG.23.

The apparatus may include additional components that perform each of the blocks of the algorithm in the flowcharts ofFIGS.23-25. As such, each block in the flowcharts ofFIGS.23-25may be performed by a component and the apparatus may include one or more of those components. The components may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by a processor configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by a processor, or some combination thereof.

As shown, the apparatus2702may include a variety of components configured for various functions. In one configuration, the apparatus2702, and in particular the baseband unit2704, includes means for receiving timing information for a user equipment (UE) indicating a first minimum K1 value associated with a first decoding scheme and a second minimum K1 value associated with a second decoding scheme, means for transmitting control information for a downlink transmission of the UE indicating a first feedback resource based on the first minimum K1 value and a second feedback resource based on the second minimum K1 value, means for transmitting the downlink transmission of the UE, means for receiving an ACK/NACK response for the downlink transmission using the first feedback resource or the second feedback resource, means for receiving an indication that the UE supports receiving multiple feedback resources, means for enabling indication of the first feedback resource and the second feedback resource for the UE, means for determining whether the ACK/NACK response will be received using the first feedback resource or the second feedback resource based on whether a conditional trigger is satisfied, means for transmitting a DCI for the UE including an incremented counter of ACK/NACK responses in response to receiving the ACK/NACK response, means for transmitting an additional downlink transmission after receiving the ACK/NACK response for the downlink transmission using the first feedback resource in response to determining that the ACK/NACK response includes an ACK, where the first feedback resource is temporally before the second feedback resource, means for retransmitting the downlink transmission of the UE after receiving the ACK/NACK response for the downlink transmission using the first feedback resource in response to determining that the ACK/NACK response includes a NACK, where the first feedback resource is temporally before the second feedback resource, means for transmitting, to the UE, a DCI including a cDAI and a tDAI, means for scheduling an additional downlink transmission for the UE having a third feedback resource and a fourth feedback resource, the third feedback resource being temporally before to the second feedback resource for the downlink transmission. The means may be one or more of the components of the apparatus2702configured to perform the functions recited by the means. As described supra, the apparatus2702may include the Tx processor316, the Rx processor370, and the controller/processor375. As such, in one configuration, the means may be the Tx processor316, the Rx processor370, and the controller/processor375configured to perform the functions recited by the means.

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, where 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.” Terms such as “if,” “when,” and “while” should be interpreted to mean “under the condition that” rather than imply an immediate temporal relationship or reaction. That is, these phrases, e.g., “when,” do not imply an immediate action in response to or during the occurrence of an action, but simply imply that if a condition is met then an action will occur, but without requiring a specific or immediate time constraint for the action to occur. 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. Sets should be interpreted as a set of elements where the elements number one or more. Accordingly, for a set of X, X would include one or more elements. 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.”

The following aspects are illustrative only and may be combined with other aspects or teachings described herein, without limitation.

Aspect 1 is a method of wireless communication at a UE, including receiving, from a network entity, control information scheduling a downlink transmission and indicating a first feedback resource for a first decoding scheme of the UE and a second feedback resource for a second decoding scheme of the UE. The method may further include receiving, from the network entity, a downlink transmission. The method may further include decoding the downlink transmission using at least one of the first decoding scheme or the second decoding scheme. The method may further include transmitting, to the network entity, a first ACK/NACK response based on the decoded downlink transmission using the first feedback resource if decoding the downlink transmission using the first decoding scheme or using the second feedback resource if decoding the downlink transmission using the second decoding scheme.

Aspect 2 is the method of aspect 1, further including transmitting, to the network entity, timing information including a first minimum K1 value associated with the first decoding scheme and a second minimum K1 value associated with the second decoding scheme.

Aspect 3 is the method of any of aspects 1-2, further including, transmitting, to the network entity, a first conditional trigger associated with the first decoding scheme, where decoding the downlink transmission using at least one of the first decoding scheme or the second decoding scheme includes decoding the downlink transmission using the first decoding scheme if one or more environmental conditions satisfies the first conditional trigger

Aspect 4 is the method of any of aspects 1-3, further including transmitting, to the network entity, an indication that the UE supports receiving a plurality of feedback resources for the downlink transmission.

Aspect 5 is the method of aspect 4, further including receiving, from the network entity, signaling that enables a configuration of the plurality of feedback resources for a PDSCH.

Aspect 6 is the method of any of aspects 1-5, further including receiving, from the network entity, a plurality of K1 values, where the control information scheduling the downlink transmission indicates at least two K1 values from the plurality of K1 values

Aspect 7 is the method of any of aspects 1-6, where the control information includes DCI having a plurality of fields or a plurality of sub-fields indicating the first feedback resource and the second feedback resource.

Aspect 8 is the method of any of aspects 1-7, further including transmitting to the network entity, an indicator that the first ACK/NACK response using the second feedback resource is pending using the first feedback resource

Aspect 9 is the method of aspect 8, where the indicator includes a NACK.

Aspect 10 is the method of aspect 8, where the first ACK/NACK response includes an ACK/NACK indicator for each codebook (CB) of a codebook group (CBG) of the downlink transmission, where the indicator that the first ACK/NACK response is pending includes at least one bit of a second ACK/NACK response transmitted to the network entity using the first feedback resource, and where the second ACK/NACK response is transmitted using the first feedback resource before the first ACK/NACK response is transmitted using the second feedback resource.

Aspect 11 is the method of aspect 8, where the first ACK/NACK response includes an ACK/NACK indicator for a TB of the downlink transmission, where the indicator that the first ACK/NACK response is pending includes at least one bit of a second ACK/NACK response transmitted to the network entity using the first feedback resource, and where the second ACK/NACK response is transmitted using the first feedback resource before the first ACK/NACK response is transmitted using the second feedback resource

Aspect 12 is the method of aspect 10, where the indicator is based on a first HARQ codebook associated with a plurality of feedback resources, the first HARQ codebook being different than a second HARQ codebook associated with a single feedback resource.

Aspect 13 is the method of aspect 12, where the at least one processor coupled to the memory is further configured to generate a multiplexed ACK/NACK response by multiplexing the first ACK/NACK response or the second ACK/NACK response based on the first HARQ codebook and a third ACK/NACK response based on the second HARQ codebook, where transmitting, to the network entity, the first ACK/NACK response includes transmitting the multiplexed ACK/NACK response.

Aspect 14 is the method of aspect 10, further including receiving, from the network entity, a second downlink transmission having a single feedback resource, decoding the second downlink transmission using the first decoding scheme, and transmitting, to the network entity, a third ACK/NACK response for the decoded second downlink transmission using the single feedback resource.

Aspect 15 is the method of any of aspects 1-14, further including retransmitting to the network entity, the first ACK/NACK response using the second feedback resource after transmitting the first ACK/NACK response using the first feedback resource.

Aspect 16 is the method of any of aspects 1-15, further including receiving, from the network entity, a scheduling DCI including a counter of ACK/NACK responses, and determining whether to retransmit, to the network entity, the first ACK/NACK response using the second feedback resource after transmitting the first ACK/NACK response using the first feedback resource if the counter of ACK/NACK responses does not meet or exceed a threshold value.

Aspect 17 is the method of any of aspects 1-16, further including receiving, from the network entity, additional control information after transmitting, to the network entity, the first ACK/NACK response using the first feedback resource, the additional control information scheduling at least one of an additional downlink transmission or a retransmission of the downlink transmission, and skipping retransmission, to the network entity, of the first ACK/NACK response using the second feedback resource in response to receiving, from the network entity, the additional control information.

Aspect 18 is the method of any of aspects 1-17, where the control information includes multiple downlink assignment index (DAI) counter values.

Aspect 19 is a method of wireless communication at a network entity, including receiving timing information for a user equipment (UE) indicating a first minimum K1 value associated with a first decoding scheme and a second minimum K1 value associated with a second decoding scheme. The method may also include transmitting control information for a downlink transmission of the UE indicating a first feedback resource based on the first minimum K1 value and a second feedback resource based on the second minimum K1 value. The method may also include transmitting the downlink transmission of the UE. The method may also include receiving an ACK/NACK response for the downlink transmission using the first feedback resource or the second feedback resource.

Aspect 20 is the method of aspect 19, further including receiving information that the UE supports receiving multiple feedback resources. The method may also include enabling indication of the first feedback resource and the second feedback resource for the UE.

Aspect 21 is the method of any of aspects 19-20, where indicating the first feedback resource and the second feedback resource includes indicating at least a first K1 value via one or more of an RRC or a scheduling DCI.

Aspect 22 is the method of aspect 21, where the scheduling DCI includes a first selection of the first K1 value from a first set of K1 values transmitted to the UE in a first RRC message.

Aspect 23 is the method of aspect 22, where the scheduling DCI includes a second selection of a second K1 value from the first set of K1 values

Aspect 24 is the method of any of aspects 19-23, further including determining whether the ACK/NACK response will be received using the first feedback resource or the second feedback resource based on whether a conditional trigger is satisfied.

Aspect 25 is the method of any of aspects 19-24, further including transmitting a DCI for the UE including an incremented counter of ACK/NACK responses in response to receiving the ACK/NACK response.

Aspect 26 is the method of any of aspects 19-25, further including transmitting an additional downlink transmission after receiving the ACK/NACK response for the downlink transmission using the first feedback resource in response to determining that the ACK/NACK response includes an ACK, where the first feedback resource is temporally before the second feedback resource

Aspect 27 is the method of any of aspects 19-26, further including retransmitting the downlink transmission of the UE after receiving the ACK/NACK response for the downlink transmission using the first feedback resource in response to determining that the ACK/NACK response includes a NACK, where the first feedback resource is temporally before the second feedback resource.

Aspect 28 is the method of any of aspects 19-27, further including transmitting, to the UE, a DCI including a cDAI and a tDAI.

Aspect 29 is an apparatus for wireless communication at a UE including at least one processor coupled to a memory and configured to implement any of aspects 1 to 19.

Aspect 30 is an apparatus for wireless communication at a network entity including at least one processor coupled to a memory and configured to implement any of aspects 20 to 28.

Aspect 31 is an apparatus for wireless communication including means for implementing any of aspects 1 to 28.

Aspect 32 is a computer-readable medium storing computer executable code, where the code when executed by a processor causes the processor to implement any of aspects 1 to 28.