WO2025030361A1

WO2025030361A1 - Sidelink feedback channel and uplink control channel timeline for multiple sidelink feedback channels

Info

Publication number: WO2025030361A1
Application number: PCT/CN2023/111670
Authority: WO
Inventors: Shaozhen GUO; Chih-Hao Liu; Siyi Chen; Luanxia YANG; Changlong Xu; Jing Sun; Xiaoxia Zhang
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2023-08-08
Filing date: 2023-08-08
Publication date: 2025-02-13
Anticipated expiration: 2026-02-08

Abstract

Various aspects of the present disclosure generally relate to wireless communication. A first user equipment (UE) may transmit, to a second UE, a physical sidelink shared channel (PSSCH) transmission. The first UE may receive, from the second UE, a physical sidelink feedback channel (PSFCH) transmission during a PSFCH occasion of multiple PSFCH occasions. The first UE may transmit, based at least in part on the PSFCH transmission, a physical uplink control channel (PUCCH) transmission during a PUCCH occasion of multiple PUCCH occasions. The PSSCH transmission may be associated with the multiple PUCCH occasions based at least in part on the PSSCH transmission being associated with the multiple PSFCH occasions.

Description

SIDELINK FEEDBACK CHANNEL AND UPLINK CONTROL CHANNEL TIMELINE FOR MULTIPLE SIDELINK FEEDBACK CHANNELS

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and specifically, to techniques and apparatuses for physical sidelink feedback channel (PSFCH) and physical uplink control channel (PUCCH) timeline for multiple PSFCH channels.

BACKGROUND

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

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

Wireless communication systems may support sidelink operations. In a sidelink operation, a first UE may directly communicate with a second UE. In a sidelink mode 1 operation, a resource used by the first UE to communicate with the second UE may be allocated by a network node. For example, the network node may transmit downlink control information (DCI) to the first UE. The DCI may indicate the resource to be used by the first UE. The network node, after transmitting the DCI to the first UE, may receive feedback from the first UE. The feedback may indicate whether a sidelink transmission between the first UE and the second UE via the allocated resource was successful. In some examples, a timeline used for transmitting the feedback may lead to increased latency, which may degrade an overall system performance.

SUMMARY

Some aspects described herein relate to an apparatus for wireless communication at a first user equipment (UE) . The apparatus may include one or more memories and one or more processors coupled to the one or more memories. The one or more processors may be configured to transmit, to a second UE, a physical sidelink shared channel (PSSCH) transmission. The one or more processors may be configured to receive, from the second UE, a physical sidelink feedback channel (PSFCH) transmission during a PSFCH occasion of multiple PSFCH occasions. The one or more processors may be configured to transmit, responsive to the PSFCH transmission, a physical uplink control channel (PUCCH) transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

Some aspects described herein relate to an apparatus for wireless communication at a network node. The apparatus may include one or more memories and one or more processors coupled to the one or more memories. The one or more processors may be configured to transmit DCI. The one or more processors may be configured to receive, in accordance with a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a PSSCH transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

Some aspects described herein relate to a method of wireless communication performed at a first UE. The method may include transmitting, to a second UE, a PSSCH transmission. The method may include receiving, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions. The method may include transmitting, responsive to the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

Some aspects described herein relate to a method of wireless communication performed at a network node. The method may include transmitting DCI. The method may include receiving, in accordance with a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a PSSCH transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a first UE. The set of instructions, when executed by one or more processors of the first UE, may cause the first UE to transmit, to a second UE, a PSSCH transmission. The set of instructions, when executed by one or more processors of the first UE, may cause the first UE to receive, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions. The set of instructions, when executed by one or more processors of the first UE, may cause the first UE to transmit, responsive to the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a network node. The set of instructions, when executed by one or more processors of the network node, may cause the network node to transmit DCI. The set of instructions, when executed by one or more processors of the network node, may cause the network node to receive, in accordance with a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a PSSCH transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

Some aspects described herein relate to a first apparatus for wireless communication. The first apparatus may include means for transmitting, to a second apparatus, a PSSCH transmission. The first apparatus may include means for receiving, from the second apparatus, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions. The first apparatus may include means for transmitting, responsive to the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for transmitting DCI. The apparatus may include means for receiving, in accordance with a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a PSSCH transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

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

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

BRIEF DESCRIPTION OF THE DRAWINGS

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

Figure 1 is a diagram illustrating an example of a wireless network.

Figure 2 is a diagram illustrating an example of a network node in communication with a user equipment (UE) in a wireless network.

Figure 3 is a diagram illustrating an example of a physical uplink control channel (PUCCH) transmission based at least in part on a physical sidelink feedback channel (PSFCH) reception.

Figure 4 is a diagram illustrating an example of a PUCCH transmission based at least in part on multiple PSFCH occasions.

Figure 5 is a diagram illustrating an example of multiple PSFCH occasions and multiple PUCCH occasions.

Figures 6-16 are diagrams illustrating examples associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

Figures 17-18 are diagrams illustrating example processes associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

Figures 19-20 are diagrams of example apparatuses for wireless communication.

DETAILED DESCRIPTION

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

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

Wireless communication systems may support sidelink operations in a sidelink unlicensed band. In a sidelink operation, a first user equipment (UE) may directly communicate with a second UE. In a sidelink mode 1 operation, a resource used by the first UE to communicate with the second UE may be allocated by a network node, whereas in a sidelink mode 2 operation, the resource may be selected by the first UE without intervention from the network node. For example, in the sidelink mode 1 operation, the network node may transmit downlink control information (DCI) to the first UE. The DCI may indicate the resource to be used by the first UE. The network node, after transmitting the DCI to the first UE, may receive feedback from the first UE. The feedback may include an acknowledgement (ACK) or a negative acknowledgement (NACK) , which may indicate whether a sidelink transmission between the first UE and the second UE via the allocated resource was successful. In some examples, a timeline used for transmitting the feedback may lead to increased latency, which may degrade an overall system performance.

The network node may transmit the DCI to the first UE. The first UE may transmit, to a second UE, a physical sidelink shared channel (PSSCH) transmission based at least in part on the DCI. The PSSCH transmission may be associated with sidelink data. For example, the DCI may indicate the resource for the PSSCH transmission. The second UE may transmit, to the first UE, a physical sidelink feedback channel (PSFCH) transmission, which may be based at least in part on a receipt of the PSSCH transmission. The PSFCH transmission may indicate feedback associated with the PSSCH transmission. The second UE may transmit the PSFCH transmission in one of multiple PSFCH occasions. A PSFCH occasion may be an opportunity for the second UE to transmit the PSFCH transmission. When the second UE does not transmit the PSFCH transmission in one PSFCH occasion, the second UE may transmit the PSFCH transmission in a next PSFCH occasion. The first UE may receive the PSFCH transmission from the second UE. The first UE may transmit, to the network node, a physical uplink control channel (PUCCH) transmission, which may be based at least in part on a receipt of the PSFCH transmission from the second UE. In other words, the PUCCH transmission may indicate whether the PSSCH transmission was successfully received by the second UE.

A last PSFCH occasion may be used as a reference slot for the PUCCH transmission. However, when the first UE receives the PSFCH transmission in an earlier PSFCH occasion before the last PSFCH occasion (for example, in a second PSFCH occasion out of four possible PSFCH occasions) , the first UE may still need to wait for a PUCCH occasion that is associated with the last PSFCH occasion because the last PSFCH occasion is used as the reference slot. In this case, the PUCCH transmission may be associated with a relatively large latency. The second UE may have received the PSFCH transmission relatively early, but may need to wait for relatively long period of time before able to transmit the PUCCH transmission to the network node.

Various aspects relate generally to configuring a PSFCH-to-PUCCH hybrid automatic repeat request (HARQ) ACK (HARQ-ACK) timeline, which may enable HARQ-ACK feedback in an earlier PUCCH occasion of multiple PUCCH occasions. Some aspects more specifically relate to a PSFCH and PUCCH timeline for multiple PSFCH channels. In some examples, a first UE may receive, from a network node, DCI. The DCI may indicate a PSFCH-to-HARQ feedback timing value. The first UE may transmit, to a second UE and in accordance with the DCI, a PSSCH transmission. The first UE may receive, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions. The first UE may transmit, based at least in part on the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions. The PSFCH-to-HARQ feedback timing value may be associated with the PUCCH occasion. The PSSCH transmission may be associated with the multiple PUCCH occasions based at least in part on the PSSCH transmission being associated with the multiple PSFCH occasions. In other words, for a sidelink Mode 1, when the PSSCH transmission is associated with the multiple PSFCH occasions, the PSSCH transmission may be associated with the multiple PUCCH occasions.

Particular aspects of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. In some examples, by supporting an association of a PSSCH to multiple PUCCH occasions based at least in part on the PSSCH being associated with multiple PSFCH occasions, the described techniques can be used by the first UE to transmit a PUCCH transmission based at least in part on a PSFCH-to-PUCCH timeline for multiple PSFCHs for a Mode 1 in sidelink unlicensed (SL-U) . The PSFCH-to-PUCCH timeline for the multiple PSFCHs may allow the first UE to transmit the PUCCH transmission in an earlier PUCCH occasion within the multiple PUCCH occasions, which may reduce an overall latency and improve a performance of the first UE and/or the network node. The PSFCH-to-PUCCH timeline for the multiple PSFCHs may reduce the overall latency for HARQ-ACK feedback to the network node, even when the first UE receives the PSFCH transmission from the second UE in an earlier PSFCH occasion before a last PSFCH occasion within the multiple PSFCH occasions, thereby improving the performance of the first UE and/or the network node.

Figure 1 is a diagram illustrating an example of a wireless network. The wireless network 100 may be or may include elements of a 5G (for example, NR) network or a 4G (for example, Long Term Evolution (LTE) ) network, among other examples. The wireless network 100 may include one or more network nodes 110 (shown as a network node (NN) 110a, a network node 110b, a network node 110c, and a network node 110d) , a UE 120 or multiple UEs 120 (shown as a UE 120a, a UE 120b, a UE 120c, a UE 120d, and a UE 120e) , or other network entities. A network node 110 is an entity that communicates with UEs 120. As shown, a network node 110 may include one or more network nodes. For example, a network node 110 may be an aggregated network node, meaning that the aggregated network node is configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node (for example, within a single device or unit) . As another example, a network node 110 may be a disaggregated network node (sometimes referred to as a disaggregated base station) , meaning that the network node 110 is configured to utilize a protocol stack that is physically or logically distributed among two or more nodes (such as one or more central units (CUs) , one or more distributed units (DUs) , or one or more radio units (RUs) ) .

In some examples, a network node 110 is or includes a network node that communicates with UEs 120 via a radio access link, such as an RU. In some examples, a network node 110 is or includes a network node that communicates with other network nodes 110 via a fronthaul link or a midhaul link, such as a DU. In some examples, a network node 110 is or includes a network node that communicates with other network nodes 110 via a midhaul link or a core network via a backhaul link, such as a CU. In some examples, a network node 110 (such as an aggregated network node 110 or a disaggregated network node 110) may include multiple network nodes, such as one or more RUs, one or more CUs, or one or more DUs. A network node 110 may include, for example, an NR network node, an LTE network node, a Node B, an eNB (for example, in 4G) , a gNB (for example, in 5G) , an access point, or a transmission reception point (TRP) , a DU, an RU, a CU, a mobility element of a network, a core network node, a network element, a network equipment, and/or a RAN node. In some examples, the network nodes 110 may be interconnected to one another or to one or more other network nodes 110 in the wireless network 100 through various types of fronthaul, midhaul, or backhaul interfaces, such as a direct physical connection, an air interface, or a virtual network, using any suitable transport network.

Each network node 110 may provide communication coverage for a particular geographic area. In the Third Generation Partnership Project (3GPP) , the term “cell” can refer to a coverage area of a network node 110 or a network node subsystem serving this coverage area, depending on the context in which the term is used.

A network node 110 may provide communication coverage for a macro cell, a pico cell, a femto cell, or another type of cell. A macro cell may cover a relatively large geographic area (for example, several kilometers in radius) and may allow unrestricted access by UEs 120 with service subscriptions. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs 120 with service subscription. A femto cell may cover a relatively small geographic area (for example, a home) and may allow restricted access by UEs 120 having association with the femto cell (for example, UEs 120 in a closed subscriber group (CSG) ) . A network node 110 for a macro cell may be referred to as a macro network node. A network node 110 for a pico cell may be referred to as a pico network node. A network node 110 for a femto cell may be referred to as a femto network node or an in-home network node.

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

A network controller 130 may couple to or communicate with a set of network nodes 110 and may provide coordination and control for these network nodes 110. The network controller 130 may communicate with the network nodes 110 via a backhaul communication link. The network nodes 110 may communicate with one another directly or indirectly via a wireless or wireline backhaul communication link. In some aspects, the network controller 130 may be a CU or a core network device, or the network controller 130 may include a CU or a core network device.

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

The UEs 120 may be dispersed throughout the wireless network 100, and each UE 120 may be stationary or mobile. A UE 120 may include, for example, an access terminal, a terminal, a mobile station, or a subscriber unit. A UE 120 may be a cellular phone (for example, a smart phone) , a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device, a biometric device, a wearable device (for example, a smart watch, smart clothing, smart glasses (for example, an augmented reality (AR) , virtual reality (VR) , mixed reality, or extended reality (XR) headset) , a smart wristband, smart jewelry (for example, a smart ring or a smart bracelet) ) , an entertainment device (for example, a music device, a video device, or a satellite radio) , a vehicular component or sensor, a smart meter/sensor, industrial manufacturing equipment, a global positioning system device, a UE function of a network node, or any other suitable device that is configured to communicate via a wireless medium. Some UEs 120 (for example, UEs 102a and 120e) may communicate directly using one or more sidelink channels (for example, without a network node as an intermediary to communicate with one another) .

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

In some examples, two or more UEs 120 (for example, shown as UE 120a and UE 120e) may communicate directly using one or more sidelink channels (for example, without using a network node 110 as an intermediary to communicate with one another) . For example, the UEs 120 may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (for example, which may include a vehicle-to-vehicle (V2V) protocol using for example a PC5 interface for direct communication, a vehicle-to-infrastructure (V2I) protocol, or a vehicle-to-pedestrian (V2P) protocol) , or a mesh network. In such examples, a UE 120 may perform scheduling operations, resource selection operations, or other operations described elsewhere herein as being performed by the network node 110. In other examples, the two or more UEs 120 may communicate through a vehicle-to-network-vehicle (V2N2V) protocol for example by communicating through a Uu interface using the LTE and/or NR uplink and downlink.

In some aspects, a UE (for example, the UE 120) may include a communication manager 140. As described in more detail elsewhere herein, the communication manager 140 may transmit, to a second UE, a PSSCH transmission; receive, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions; and transmit, responsive to the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions. Additionally, or alternatively, the communication manager 140 may perform one or more other operations described herein.

In some aspects, a network node (for example, the network node 110) may include a communication manager 150. As described in more detail elsewhere herein, the communication manager 150 may transmit DCI; and receive, in accordance with a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a PSSCH transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions. Additionally, or alternatively, the communication manager 150 may perform one or more other operations described herein.

Figure 2 is a diagram illustrating an example network node in communication with a UE in a wireless network. The network node may correspond to the network node 110 of Figure 1. Similarly, the UE may correspond to the UE 120 of Figure 1. The network node 110 may be equipped with a set of antennas 234a through 234t, such as T antennas (T ≥ 1) . The UE 120 may be equipped with a set of antennas 252a through 252r, such as R antennas (R ≥ 1) . The network node 110 of depicted in Figure 2 includes one or more radio frequency components, such as antennas 234 and a modem 232. In some examples, a network node 110 may include an interface, a communication component, or another component that facilitates communication with the UE 120 or another network node. Some network nodes 110 may not include radio frequency components that facilitate direct communication with the UE 120, such as one or more CUs, or one or more DUs.

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

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

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

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

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

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

The controller/processor 240 of the network node 110, the controller/processor 280 of the UE 120, or any other component (s) of Figure 2 may perform one or more techniques associated with a PSFCH and PUCCH timeline for multiple PSFCH channels, as described in more detail elsewhere herein. For example, the controller/processor 240 of the network node 110, the controller/processor 280 of the UE 120, or any other component (s) of Figure 2 may perform or direct operations of, for example, process 1700 of Figure 17, process 1800 of Figure 18, or other processes as described herein. The memory 242 and the memory 282 may store data and program codes for the network node 110 and the UE 120, respectively. In some examples, the memory 242 or the memory 282 may include a non-transitory computer-readable medium storing one or more instructions (for example, code or program code) for wireless communication. For example, the one or more instructions, when executed (for example, directly, or after compiling, converting, or interpreting) by one or more processors of the network node 110 or the UE 120, may cause the one or more processors, the UE 120, or the network node 110 to perform or direct operations of, for example, process 1700 of Figure 17, process 1800 of Figure 18, or other processes as described herein. In some examples, executing instructions may include running the instructions, converting the instructions, compiling the instructions, or interpreting the instructions, among other examples. In some implementations, one or more of the multiple memories may be configured to store processor-executable code that, when executed, may configure the one or more processors to perform various functions described herein (as part of a processing system) . In some other implementations, the processing system may be pre-configured to perform various functions described herein.

In some aspects, an individual processor may perform all of the functions described as being performed by one or more processors. In some aspects, one or more processors may collectively perform (or be configured or operable to perform) a set of functions. For example, a first set of (one or more) processors of the one or more processors may perform a first function described as being performed by the one or more processors, and a second set of (one or more) processors of the one or more processors may perform a second function described as being performed by the one or more processors. The first set of processors and the second set of processors may be the same set of processors or may be different sets of processors. Reference to “one or more processors” should be understood to refer to any one or more of the processors described in connection with Figure 2. Reference to “one or more memories” should be understood to refer to any one or more memories of a corresponding device, such as the memory described in connection with Figure 2. For example, functions described as being performed by one or more memories can be performed by the same subset of the one or more memories or different subsets of the one or more memories.

In some aspects, a first UE (for example, UE 120a) includes means for transmitting, to a second UE, a PSSCH transmission; means for receiving, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions; and/or means for transmitting, responsive to the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions. The means for the first UE to perform operations described herein may include, for example, one or more of communication manager 140, antenna 252, modem 254, MIMO detector 256, receive processor 258, transmit processor 264, TX MIMO processor 266, controller/processor 280, or memory 282.

In some aspects, a network node (for example, the network node 110) includes means for transmitting DCI; and/or means for receiving, in accordance with a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a PSSCH transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions. The means for the network node to perform operations described herein may include, for example, one or more of communication manager 150, transmit processor 220, TX MIMO processor 230, modem 232, antenna 234, MIMO detector 236, receive processor 238, controller/processor 240, memory 242, or scheduler 246.

One PSCCH/PSSCH transmission may have N associated candidate PSFCH occasion (s) via a configuration. A UE may be associated with a certain behavior for transmitting a PSFCH. For one PSCCH/PSSCH transmission, a UE (for example, a PSCCH/PSSCH receiver UE) may attempt to transmit the PSFCH on a candidate PSFCH occasion when the UE fails to transmit the PSFCH on previous PSFCH occasion (s) due to listen-before-talk (LBT) failure. For one PSCCH/PSSCH transmission, the UE may attempt to transmit the PSFCH on the candidate PSFCH occasion when the UE fails to transmit the PSFCH on the previous PSFCH occasion (s) (for example, due to LBT failure, or due to uplink/sidelink prioritization) . In some examples, no additional UE behavior may be specified regarding transmitting the PSFCH due to LBT failure. The UE may be associated with a certain behavior for receiving a PSFCH. For a HARQ round-trip-time (RTT) restriction, a minimum time gap may be defined between two selected resources of a transport block (TB) when the PSFCH is configured for a resource pool associated with the two selected resources. A reference slot n may be defined for a PUCCH transmission to report HARQ in a sidelink mode 1 operation.

In the sidelink mode 1 operation, the UE may provide HARQ-ACK information from a sidelink in a PUCCH transmission within slot n+k (subject to overlapping condition) with reference to slots for PUCCH transmissions and for a number of PSFCH reception occasions ending in slot n, where k is a number of slots indicated by a PSFCH-to-HARQ feedback timing indicator field in DCI (for example, DCI 3_0) .

Figure 3 is a diagram illustrating an example 300 of a PUCCH transmission based at least in part on a PSFCH reception.

As shown in Figure 3, a network node may transmit DCI (for example, DCI 3_0) to a first UE (for example, a Tx UE) . The first UE may transmit a PSSCH transmission to a second UE (for example, a receive (Rx) UE) . The second UE may transmit, to the first UE, a PSFCH transmission in slot n. The PSFCH transmission may be based at least in part on a receipt of the PSSCH transmission. The first UE may transmit, to the network node, a PUCCH transmission in slot n+k. The PUCCH transmission may indicate a content of the PSFCH transmission.

When multiple PSFCH candidates are associated with one PSSCH, a reference slot for a PUCCH transmission (for example, slot n) may be a slot after a last PSFCH candidate because an ACK or NACK over a PC-5 interface may be received at the last PSFCH candidate.

Figure 4 is a diagram illustrating an example 400 of a PUCCH transmission based at least in part on multiple PSFCH occasions.

As shown in Figure 4, a network node may transmit DCI (for example, DCI 3_0) to a first UE (for example, a Tx UE) . The first UE may transmit a PSSCH transmission to a second UE (for example, an Rx UE) . Multiple PSFCH occasions (for example, four PSFCH occasions) may be associated with the PSSCH transmission. A reference slot for a PUCCH transmission (for example, slot n) may be a slot after a last PSFCH candidate of the multiple PSFCH occasions. The first UE may transmit, to the network node, the PUCCH transmission in slot n+k.

In some examples, using a last PSFCH occasion as a reference slot for a PUCCH transmission may lead to a relatively large latency for HARQ-ACK feedback to a network node. A UE may receive a PSFCH transmission in an earlier PSFCH transmission before a last PSFCH occasion, so the UE should transmit the HARQ-ACK feedback to the network node as early as possible. For example, when the UE receives the PSFCH transmission in a third PSFCH occasion in slot n’, the UE may transmit the PSFCH transmission in slot n’+k instead of waiting until slot n+k, which may reduce the latency for the HARQ-ACK feedback.

Figure 5 is a diagram illustrating an example 500 of multiple PSFCH occasions and multiple PUCCH occasions.

As shown in Figure 5, a network node may transmit DCI (for example, DCI 3_0) to a first UE (for example, a Tx UE) . The DCI may indicate a PSFCH-to-HARQ feedback timing indicator k. The first UE may transmit a PSSCH transmission to a second UE (for example, an Rx UE) . Multiple PSFCH occasions (for example, four PSFCH occasions) may be associated with the PSSCH transmission. A third PSFCH occasion, of the multiple PSFCH occasions, may be associated with slot n’. A fourth PSFCH occasion, of the multiple PSFCH occasions, may be associated with slot n. In this case, the second UE may transmit a PSFCH transmission in the third PSFCH occasion. The first UE may transmit, to the network node, a PUCCH transmission, in slot n’+k instead of waiting until slot n+k, which may reduce a latency for a HARQ-ACK feedback.

In some examples, using a last PSFCH occasion as a reference slot for a PUCCH transmission may lead to a relatively large latency. Instead, a UE may determine to use an earlier PSFCH occasion, in relation to the last PSFCH occasion. However, when the UE uses the earlier PSFCH occasion (for example, slot n’) , the UE and/or a network node may not be configured to allow a HARQ-ACK feedback in an earlier PUCCH (for example, slot n’+k) . Rather, the UE may only be configured to perform the HARQ-ACK feedback in a later PUCCH (for example, slot n+k) because the last PSFCH occasion is used as a reference slot for the PUCCH transmission. In other words, the UE and/or the network node may follow a PSFCH-to-PUCCH HARQ timeline that does not support the UE transmitting the HARQ-ACK feedback in the earlier PUCCH. As a result, the HARQ-ACK feedback may be associated with the relatively large latency, thereby degrading a performance of the UE and/or the network node.

In various aspects of techniques and apparatuses described herein, a first UE may receive, from a network node, DCI. The DCI may indicate a PSFCH-to-HARQ feedback timing value. The first UE may transmit, to a second UE and in accordance with the DCI, a PSSCH transmission. The first UE may receive, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions. The first UE may transmit, to the network node and based at least in part on the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions. The PSFCH-to-HARQ feedback timing value may be associated with the PUCCH occasion. The PSSCH transmission may be associated with the multiple PUCCH occasions based at least in part on the PSSCH transmission being associated with the multiple PSFCH occasions.

In some aspects, the first UE may be able to transmit the PUCCH transmission based at least in part on a PSFCH-to-PUCCH timeline for multiple PSFCHs for a Mode 1 in SL-U. The PSFCH-to-PUCCH timeline for the multiple PSFCHs may allow the first UE to transmit the PUCCH transmission in an earlier PUCCH occasion within the multiple PUCCH occasions, which may reduce an overall latency and improve a performance of the first UE and/or the network node. The PSFCH-to-PUCCH timeline for the multiple PSFCHs may reduce the overall latency for HARQ-ACK feedback to the network node, even when the first UE receives the PSFCH transmission from the second UE in an earlier PSFCH occasion before a last PSFCH occasion within the multiple PSFCH occasions, thereby improving the performance of the first UE and/or the network node.

Figure 6 is a diagram illustrating an example 600 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels. As shown in Figure 6, example 600 includes communication between a first UE (for example, UE 120a) , a second UE (for example, UE 120b) , and a network node (for example, network node 110) . In some aspects, the first UE, the second UE, and the network node may be included in a wireless network, such as wireless network 100.

In a first operation 602, the first UE may receive, from the network node, DCI. For example, the DCI may be a DCI format 3_0. The DCI may indicate, to the first UE, a resource for a PSSCH transmission.

In a second operation 604, the first UE may transmit, to the second UE and in accordance with the DCI, the PSSCH transmission. The first UE may transmit the PSSCH transmission via a sidelink interface between the first UE and the second UE.

In a third operation 606, the first UE may receive, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions. The multiple PSFCH occasions may be available to allow the second UE to transmit the PSFCH transmission to the first UE. The first UE may receive the PSFCH transmission via a feedback channel between the first UE and the second UE. The PSFCH transmission may indicate whether the PSSCH transmission was successfully received by the second UE. For example, the PSSCH transmission may indicate an ACK or a NACK, depending on whether the PSSCH transmission was successfully received by the second UE.

In a fourth operation 608, the first UE may transmit, to the network node and based at least in part on the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions. The PSSCH transmission may be associated with the multiple PUCCH occasions based at least in part on the PSSCH transmission being associated with the multiple PSFCH occasions. The first UE may be permitted to transmit the PUCCH transmission in one of the multiple PUCCH occasions (for example, an earlier PUCCH occasion, depending on the PSFCH occasion in which the PSFCH transmission was received) , which may reduce an overall latency. The overall latency may be between a first time associated with a transmission of the DCI, by the network node, and a second time associated with a receipt of the PUCCH transmission, by the network node.

In some aspects, each PSFCH occasion of the multiple PSFCH occasions may be associated with one PUCCH occasion of the multiple PUCCH occasions (for example, as shown in Figure 7) . A reference slot for the PUCCH transmission may be a slot of the PSFCH occasion, and a PSFCH-to-HARQ feedback timing value associated with the PUCCH occasion may be indicated via the DCI.

In some aspects, one or more PSFCH occasions, of the multiple PSFCH occasions, may be associated with one PUCCH occasion of the multiple PUCCH occasions (for example, as shown in Figures 8-10) . The multiple PSFCH occasions may be divided into multiple PSFCH occasion groups. A PSFCH occasion group, of the multiple PSFCH occasion groups, may be associated with one PUCCH occasion of the multiple PUCCH occasions. A reference slot for the one PUCCH occasion may be a slot of a last PSFCH occasion, of the multiple PSFCH occasions, within a corresponding group of PSFCH occasions. A PSFCH-to-HARQ feedback timing value associated with the last PSFCH occasion may be indicated via the DCI. The PSFCH occasion group may be based at least in part on a number of PSFCH occasions associated with one PSSCH (N) , a configured or specified number of PUCCH occasions associated with the one PSSCH (M) . A number of PSFCH occasion groups (K) may be based at least in part on the number of PSFCH occasions associated with one PSSCH and the configured or specified number of PUCCH occasions associated with the one PSSCH.

In some aspects, a reference slot for the PUCCH occasion may be configured via radio resource control (RRC) signaling. The first UE may receive, from the network node and via the RRC signaling, an M-bits bitmap based at least in part on M PSFCH occasions being configured for the first UE, where M is an integer (for example, as shown in Figure 11) . A bit of the M-bits bitmap may be associated with an individual PSFCH occasion. The individual PSFCH occasion may be associated with a reference slot for a corresponding PUCCH occasion based at least in part on a value of the bit.

In some aspects, the PUCCH transmission may indicate a Type-1 HARQ-ACK codebook in an uplink slot. The PSSCH transmission may be associated with the multiple PSFCH occasions and the multiple PUCCH occasions. The first UE may determine a set of occasions for candidate PSSCH transmissions with corresponding PSFCH reception occasions for which the first UE is able to multiplex corresponding Type-1 HARQ-ACK codebook information in the PUCCH transmission. The first UE may transmit the PUCCH transmission that indicates the Type-1 HARQ-ACK codebook based at least in part on one or more reference slots specified or configured for the multiple PSFCH occasions. The first UE may construct the Type-1 HARQ-ACK codebook for a slot timing value in a set of slot timing values (for example, as shown in Figure 14) . The first UE, when constructing the Type-1 HARQ-ACK codebook, may determine that a slot that is the slot timing value away from the uplink slot is associated with a sidelink resource pool and includes PSFCH resources, as indicated by a sidelink resource pool bitmap and a sidelink PSFCH period. The first UE, when constructing the Type-1 HARQ-ACK codebook, may determine candidate PSSCH occasions associated with a PSFCH transmission occasion in the slot that is the slot timing value away from the uplink slot based at least in part on a PSFCH period and specified or configured reference slots. The candidate PSSCH occasions may be added to a set of occasions for candidate PSSCH transmissions based at least in part on an ascending order or a descending order of a reference slot index.

In some aspects, the PSSCH transmission may be associated with the multiple PSFCH occasions and the multiple PUCCH occasions. The PUCCH transmission may indicate a Type-2 HARQ-ACK codebook. The DCI may indicate multiple counter sidelink assignment index (SAI) fields, and each counter SAI field may be associated with one PUCCH occasion of the multiple PUCCH occasions (for example, as shown in Figure 15) . The DCI may indicate multiple PUCCH resource indicator (PRI) fields, and each PRI field may be associated with one PUCCH occasion of the multiple PUCCH occasions.

In some aspects, the first UE, when transmitting the PUCCH transmission, may transmit HARQ-ACK feedback on the PUCCH occasion of the multiple PUCCH occasions. HARQ-ACK feedback on the PUCCH occasion may be based at least in part on HARQ-ACK feedback received, from the second UE, from the associated PSFCH occasions before a reference slot of the PUCCH occasion.

In some aspects, the PSSCH transmission may be unicast. The first UE may receive, from the second UE, at least one ACK on the PSFCH occasion, of the multiple PSFCH occasions, before the reference slot of the PUCCH occasion (for example, as shown in Figure 16) . The first UE, when transmitting the HARQ-ACK feedback, may transmit an ACK. In some aspects, the PSSCH transmission may be a groupcast associated with ACK and NACK based feedback (e.g., groupcast type 2) . The first UE may receive, from each of the second UE or a third UE, at least one ACK for the second UE and the third UE on one or more PSFCH occasions, of the multiple PSFCH occasions, before the reference slot of the PUCCH occasion. The first UE, when transmitting the HARQ-ACK feedback, may transmit an ACK. In some aspects, the first UE, when transmitting the HARQ-ACK feedback, for a groupcast associated with NACK-only feedback (e.g., groupcast type 1) , may transmit a NACK on each PUCCH occasion except a last PUCCH occasion of the multiple PUCCH occasions. An ACK may be transmitted for the last PUCCH occasion based at least in part on a detection of an absence of a PSFCH on each PSFCH occasion before a reference slot of the last PUCCH occasion. In some aspects, when transmitting the PUCCH transmission, the first UE may transmit, for each HARQ-ACK feedback, an indication of whether a real ACK, a virtual ACK, a real NACK, or a virtual NACK is reported.

In some aspects, for a sidelink mode 1 operation, when a PSSCH is associated with multiple PSFCH occasions, the PSSCH may be associated with multiple PUCCH occasions. The PSSCH transmission, from the first UE (for example, a Tx UE) to the second UE (for example, an Rx UE) , may be associated with the multiple PSFCH occasions, and the PSSCH transmission may be associated with the multiple PUCCH occasions.

In some aspects, each PSFCH occasion of the multiple PSFCH occasions may be associated with one PUCCH occasion. A reference slot for an n-th PUCCH transmission (for example, n = 1, 2, …, N) may be a slot of an n-th PSFCH occasion, where k is a PSFCH-to-HARQ feedback timing value indicated by a DCI (for example, DCI 3_0) .

Figure 7 is a diagram illustrating an example 700 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 7, a network node may transmit DCI (for example, DCI 3_0) to a first UE (for example, a Tx UE) . The first UE may transmit a PSSCH transmission to a second UE (for example, an Rx UE) . Multiple PSFCH occasions (for example, four PSFCH occasions) may be associated with the PSSCH transmission, and each PSFCH occasion, of the multiple PSFCH occasions, may be associated with a separate PUCCH occasion. For example, a first PSFCH occasion associated with slot n₀ may be associated with a first PUCCH occasion associated with slot n₀ + k, a second PSFCH occasion associated with slot n₁ may be associated with a second PUCCH occasion associated with slot n₁ + k, a third PSFCH occasion associated with slot n₂ may be associated with a third PUCCH occasion associated with slot n₂ + k, and a fourth PSFCH occasion associated with slot n₃ may be associated with a fourth PUCCH occasion associated with slot n₃ + k.

In some aspects, one or more PSFCH occasions may be mapped to one PUCCH occasion. In some aspects, PSFCH occasions may be divided into multiple groups, and each group may be mapped to one PUCCH occasion. A reference slot for a PUCCH occasion may be a slot of a last PSFCH occasion within a corresponding group of PSFCH occasions, where k is a PSFCH-to-HARQ feedback timing value indicated by DCI (for example, DCI 3_0) . A PSFCH occasion group may be determined based on defined rules. In a first alternative, a first PSFCH occasion group may include PSFCH occasion 1, …, N- (K-1) *ceil (N/K) , and a second to last PSFCH occasion group may include PSFCH occasion N- (K-k+1) *ceil (N/K) +1, …, N- (K-k) *ceil (N/K) , where k = 2, …, K. In a second alternative, a first to (K-1) th PSFCH occasion group may include PSFCH occasion (k-1) *ceil (N/K) +1, …, k*ceil (N/K) , where k=1, …, K-1, and a last PSFCH occasion group may include PSFCH occasion (K-1) *ceil (N/K) +1, …, N. Further, N is a number of PSFCH occasions associated with one PSSCH, M is a configured or specified number of PUCCH occasions associated with one PSSCH, and K = ceil (N/M) is a number of PSFCH occasion groups.

Figure 8 is a diagram illustrating an example 800 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 8, a network node may transmit DCI (for example, DCI 3_0) to a first UE (for example, a Tx UE) . The first UE may transmit a PSSCH transmission to a second UE (for example, an Rx UE) . Multiple PSFCH occasions (for example, four PSFCH occasions) may be associated with the PSSCH transmission, and one or more PSFCH occasions may be mapped to one PUCCH occasion. For example, when N = 4, M = 2, the number of PSFCH occasion groups is K = ceil (N/M) = 2, a first PSFCH occasion associated with slot n₀ and a second PSFCH occasion associated with slot n₁ may be associated with a first group. The first group may be associated with a first PUCCH occasion associated with slot n₁ + k. The second PSFCH occasion, being the last PSFCH occasion in the first group, may be the reference slot for the first PUCCH occasion. A third PSFCH occasion associated with slot n₂ and a fourth PSFCH occasion associated with slot n₃ may be associated with a second group. The second group may be associated with a second PUCCH occasion associated with slot n₃ + k. The fourth PSFCH occasion, being the last PSFCH occasion in the second group, may be the reference slot for the second PUCCH occasion.

Figure 9 is a diagram illustrating an example 900 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 9, when N = 3, M = 2, the number of PSFCH occasion groups is K = ceil (N/M) = 2, and when a first alternative is employed, a first PSFCH occasion associated with slot n₀ may be associated with a first group. The first group may be associated with a first PUCCH occasion associated with slot n₀ + k. The first PSFCH occasion, being the last PSFCH occasion in the first group, may be the reference slot for the first PUCCH occasion. A second PSFCH occasion associated with slot n₁ and a third PSFCH occasion associated with slot n₂ may be associated with a second group. The second group may be associated with a second PUCCH occasion associated with slot n₂ + k. The third PSFCH occasion, being the last PSFCH occasion in the second group, may be the reference slot for the second PUCCH occasion.

Figure 10 is a diagram illustrating an example 1000 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 10, when N = 3, M = 2, the number of PSFCH occasion groups is K = ceil (N/M) = 2, and when a second alternative is employed, a first PSFCH occasion associated with slot n₀ and a second PSFCH occasion associated with slot n₁ may be associated with a first group. The first group may be associated with a first PUCCH occasion associated with slot n₁ + k. The second PSFCH occasion, being the last PSFCH occasion in the first group, may be the reference slot for the first PUCCH occasion. A third PSFCH occasion associated with slot n₂ may be associated with a second group. The second group may be associated with a second PUCCH occasion associated with slot n₂ + k. The third PSFCH occasion, being the last PSFCH occasion in the second group, may be the reference slot for the second PUCCH occasion.

In some aspects, a reference slot for each PUCCH occasion may be configured via RRC signaling. When M PSFCH occasions are configured, an M-bits bitmap may be configured, where each bit may be associated with a PSFCH occasion. When a bit value for a corresponding PSFCH is set to 1, a PSFCH may be a reference slot for a corresponding PUCCH occasion.

Figure 11 is a diagram illustrating an example 1100 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 11, a network node may transmit DCI (for example, DCI 3_0) to a first UE (for example, a Tx UE) . The first UE may transmit a PSSCH transmission to a second UE (for example, an Rx UE) . Four PSFCH occasions may be associated with the PSSCH transmission, and one or more PSFCH occasions may be mapped to one PUCCH occasion. For example, a first PSFCH occasion associated with slot n₀ and a second PSFCH occasion associated with slot n₁ may be associated with a first PUCCH occasion associated with slot n₁ + k. A third PSFCH occasion associated with slot n₂ and a fourth PSFCH occasion associated with slot n₃ may be associated with a second PUCCH occasion associated with slot n₃ + k. When the four PSFCH occasions are configured, a 4-bit bitmap may be configured via RRC signaling, where each bit may be associated with a PSFCH occasion. In the 4-bit bitmap, a second bit may be set to 1, which may indicate that the second PSFCH occasion is the reference slot for the first PUCCH occasion, and a fourth bit may be set to 1, which may indicate that the fourth PSFCH occasion is the reference slot for the second PUCCH occasion.

In some aspects, for a Type-1 HARQ-ACK codebook, a first UE (for example, a Tx UE) may determine a set of M_A occasions for candidate PSSCH transmissions with corresponding PSFCH reception occasions, for which the first UE may multiplex corresponding HARQ-ACK information in a PUCCH transmission in slot n_u. The first UE may transmit the Type-1 HARQ-ACK codebook based at least in part on a set of slot timing values K1 associated with a sidelink bandwidth part (BWP) , where K1 may be provided by a sidelink PSFCH-to-PUCCH (sl-PSFCH-ToPUCCH) parameter for DCI format 3_0 or a sidelink PSFCH-to-PUCCH configured grant (CG) type 1 (sl-PSFCH-ToPUCCH-CG-Type1) . The Type-1 HARQ-ACK codebook may be based at least in part on a between a sidelink subcarrier spacing (SCS) configuration μ_SL and an uplink SCS configuration μ_UL provided by a subcarrier spacing (subcarrierSpacing) parameter in a sidelink BWP configuration (SL-BWP-Config) or a sidelink BWP common configuration (SL-BWP-ConfigCommon) , and an uplink BWP (BWP-Uplink) parameter for a sidelink BWP and an active uplink BWP, respectively. The Type-1 HARQ-ACK codebook may be based at least in part on a configured sidelink resource pool bitmap. The Type-1 HARQ-ACK codebook may be based at least in part on a value of a period of PSFCH transmission occasion resources for a sidelink resource pool provided by a respective sidelink PSFCH period (sl-PSFCH-period) parameter.

In some aspects, for each K1 in a set of K1 values in descending order, the first UE may perform a first step and a second step. In the first step, when slot n_u –K1 is associated with the sidelink resource pool and includes PSFCH resources, as indicated by the sidelink resource pool bitmap and the sl-PSFCH-Period parameter, the first UE may move to the second step. Otherwise, the first UE may move to a next K1 value. In the second step, the first UE may determine candidate PSSCH occasions associated with a PSFCH transmission occasion in slot n_u –K1 based at least in part on a PSFCH period.

Figure 12 is a diagram illustrating an example 1200 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 12, a sidelink resource pool bitmap may indicate sidelink slots, where a 1 may represent a sidelink slot and a 0 may represent a non-sidelink slot. A sidelink slot may be associated with a PSFCH occasion. As an example, the set of K1 values may be {1, 2, 4, 5, 6} based at least in part on RRC signaling, a sl-PSFCH-Period = 2, and a sidelink minimum time gap for PSFCH (sl-MinTimeGapPSFCH) = 2. A PUCCH transmission may be transmitted in slot n_u. A UE (for example, a first UE) may determine, based at least in part on the sidelink resource pool bitmap, that slot n_u-6 is associated with a sidelink resource pool and includes PSFCH resources. For K1 = 6, slot n_u-6 may be associated with the sidelink resource pool and may include PSFCH resources. The UE may determine, based at least in part on the sl-PSFCH-Period and the sl-MinTimeGapPSFCH, candidate PSSCH occasions associated with a PSFCH transmission occasion in slot n_u-6. For example, the UE may determine that the associated candidate PSSCH occasions include slots {n_s1, n_s2} . For a PSFCH occasion in slot n_u-6, the associated candidate PSSCH occasions may include slots {n_s1, n_s2} . The UE may determine, based at least in part on the sidelink resource pool bitmap, that slot n_u-5 is associated with the sidelink resource pool but does not include PSFCH resources. The UE may determine, based at least in part on the sidelink resource pool bitmap, that slot n_u-4 is not associated with the sidelink resource pool and does not include PSFCH resources. The UE may determine, based at least in part on the sidelink resource pool bitmap, that slot n_u-2 is associated with a sidelink resource pool and includes PSFCH resources. For K1 = 2, slot n_u-2 may be associated with the sidelink resource pool and may include PSFCH resources. The UE may determine, based at least in part on the sl-PSFCH-Period and the sl-MinTimeGapPSFCH, candidate PSSCH occasions associated with a PSFCH transmission occasion in slot n_u-2. For example, the UE may determine that the associated candidate PSSCH occasions include slots {n_s3, n_s4} . For a PSFCH occasion in slot n_u-2, the associated candidate PSSCH occasions may include slots {n_s3, n_s4} . The UE may determine, based at least in part on the sidelink resource pool bitmap, that slot n_u-1 is associated with the sidelink resource pool but does not include PSFCH resources.

In some aspects, for a PSSCH associated with one PSFCH, for a given PSFCH transmission occasion, a number of candidate PSSCH occasions associated with the given PSFCH transmission occasion may be no more than N_PSFCH, which may correspond to a number of sidelink slots within a PSFCH period. For a PSSCH associated with multiple PSFCH occasions, when the PSSCH is mapped to multiple PUCCH occasions, for example, multiple reference slots for PUCCH are configured, a number of candidate PSSCH occasions may be a multiple of N_PSFCH, which may be related to a number of reference slots used for a PUCCH. Thus, a Type-1 codebook may need to be enhanced for multiple PSFCH occasions with multiple reference slots.

Figure 13 is a diagram illustrating an example 1300 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 13, a plurality of sidelink slots may include slots n_s1, n_s2, n_s3, n_s4, n_s5, and n_s6. The slots n_s2, n_s4, and n_s6 may be associated with PSFCH occasions, respectively. A reference slot 1302 may be a first reference slot for slot n_s, 3 and n_s, 4. The reference slot 1302 may be a second reference slot for slot n_s, 1 and n_s, 2. A reference slot 1304 may be a first reference slot for slot n_s, 5 and n_s, 6. The reference slot 1304 may be a second reference slot for slot n_s, 3 and n_s, 4. Slot n_s, 1 and n_s, 2 may be associated with two reference slots, and slot n_s, 3 and n_s, 4 may be associated with two reference slots. A PUCCH transmission may be transmitted in slot n_u. The reference slot 1302 may be associated with slot n_u-K_1, 1. The reference slot 1304 may be associated with slot n_u-K_1, 2. In this case, multiple reference slots for a PUCCH may be configured. However, a Type-1 codebook may need to be enhanced for multiple PSFCH occasions with multiple reference slots.

In some aspects, for a Type-1 HARQ-ACK codebook, when a PSSCH is associated with multiple PSFCH occasions and multiple PUCCH occasions, a first UE may determine a set of M_A occasions for candidate PSSCH transmissions with corresponding PSFCH reception occasions for which the first UE may multiplex corresponding HARQ-ACK information in a PUCCH transmission in slot n_u. The first UE may transmit the Type-1 HARQ-ACK codebook based at least in part on reference slot (s) specified/configured for the multiple PSFCH occasions, in addition to existing parameters/configurations. The existing parameters/configurations may include a set of slot timing values K1, a ratioa configured sidelink resource pool bitmap, and/or a value of a period of PSFCH transmission occasion resources.

In some aspects, during a Type-1 HARQ-ACK codebook construction procedure, for each K1 in a set of K1 values in descending order, the first UE may perform a first step and a second step. In the first step, when slot n_u –K1 is associated with a sidelink resource pool and includes PSFCH resources, as indicated by the sidelink resource pool bitmap and an sl-PSFCH-Period parameter, the first UE may move to the second step. Otherwise, the first UE may move to a next K1 value. In the second step, the first UE may determine candidate PSSCH occasions associated with a PSFCH transmission occasion in slot n_u –K1 based at least in part on a PSFCH period and the specified/configured reference slots. The PSSCH occasions may be added to the set of M_A occasions for candidate PSSCH transmissions based at least in part on an ascending/descending order of a reference slot index. The PSSCH occasions with slot n_u –K1 as a first/last reference slot may be added first, and then PSSCH occasions with slot n_u –K1 as a second/second last reference slot may be added.

Figure 14 is a diagram illustrating an example 1400 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 14, a plurality of sidelink slots may include slots n_s1, n_s2, n_s3, n_s4, n_s5, and n_s6. The slots n_s2, n_s4, and n_s6 may be associated with PSFCH occasions, respectively. A reference slot 1402 may be a first reference slot for slot n_s, 3 and n_s, 4. The reference slot 1402 may be a second reference slot for slot n_s, 1 and n_s, 2. A reference slot 1404 may be a first reference slot for slot n_s, 5 and n_s, 6. The reference slot 1404 may be a second reference slot for slot n_s, 3 and n_s, 4. A PUCCH transmission may be transmitted in slot n_u. In this case, multiple reference slots for a PUCCH may be configured.

In some aspects, for K1 = 6, in a first step, a first UE may determine that slot n_u-6 is associated with a sidelink resource pool and may include PSFCH resources. The first UE may move to a second step. In the second step, the first UE may determine candidate PSSCH occasions with corresponding PSFCH occasions in slot n_u-6. Firstly, the first UE may determine the candidate PSSCH occasions with slot n_u-6 as a second reference slot, for example, candidate PSSCH occasions in slot n_s, 1 and n_s, 2. Then the first UE may determine the candidate PSSCH occasions with slot n_u-6 as a first reference slot, for example, candidate PSSCH occasions in slot n_s, 3 and n_s, 4. Thus, for slot n_u-6, the candidate PSSCH occasions may be {n_s, 1, n_s, 2, n_s, 3, n_s, 4} .

In some aspects, for K1 = 5, in a first step, the first UE may determine that slot n_u-5 is associated with the sidelink resource pool but does not include PSFCH resources, so the first UE may move to a next K1. For K1 = 4, in a first step, the first UE may determine that slot n_u-4 is not associated with the sidelink resource pool and does not include PSFCH resources, so the first UE may move to a next K1. For K1 = 2, in a first step, the first UE may determine that slot n_u-6 is associated with the sidelink resource pool and may include PSFCH resources. The first UE may move to a second step. In the second step, the first UE may determine candidate PSSCH occasions with corresponding PSFCH occasions in slot n_u-2. Firstly, the first UE may determine the candidate PSSCH occasions with slot n_u-2 as a second reference slot, for example, candidate PSSCH occasions in slot n_s, 3 and n_s, 4. Then the first UE may determine the candidate PSSCH occasions with slot n_u-6 as a first reference slot, for example, candidate PSSCH occasions in slot n_s, 5 and n_s, 6. Thus, for slot n_u-2, the candidate PSSCH occasions may be {n_s, 3, n_s, 4, n_s, 5, n_s, 6} . For K1 = 1, in a first step, the first UE may determine that slot n_u-1 is associated with the sidelink resource pool but does not include PSFCH resources.

In some aspects, for K1 = 6, a first reference slot may be associated with slot n_s, 3 and n_s, 4 and a second reference slot may be associated with slot n_s, 1 and n_s, 2. For K1 = 2, a first reference slot may be associated with slot n_s, 5 and n_s, 6 and a second reference slot may be associated with slot n_s, 3 and n_s, 4.

In some aspects, for a Type-2 HARQ-ACK codebook, when a PSSCH may be associated with multiple PSFCH occasions and multiple PUCCH occasions, multiple counter sidelink assignment index (SAI) fields may be introduced in DCI (for example, DCI format 3_0) . Each counter SAI field may be associated with one PUCCH occasion. In some aspects, multiple PUCCH resource indicator (PRI) fields may be introduced in DCI (for example, DCI format 3_0) . Each PRI field may be associated with one PUCCH occasion.

Figure 15 is a diagram illustrating an example 1500 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 15, a first UE (UE 0) may transmit a first PSSCH transmission (PSSCH #1) to a second UE (UE 1) . The first PSSCH transmission may be associated with a first PSFCH occasion, which may be associated with a first PUCCH occasion (e.g., PUCCH y) . The first UE may transmit a second PSSCH transmission (PSSCH #2) to a third UE (UE 2) . The second PSSCH transmission may be associated with a second PSFCH occasion, which may be associated with a first PUCCH occasion (e.g., PUCCH y) , and a third PSFCH occasion which may be associated with a second PUCCH occasion (e.g., PUCCH z) . A third PSSCH transmission (PSSCH #3) may be associated with a third PSFCH occasion, which may be associated with the second PUCCH occasion (e.g., PUCCH z) . A network node may transmit DCI via a PDCCH (for example, PDCCH #2) , which may be associated with the second PSSCH transmission. The DCI may indicate a first counter SAI (for example, 2) , a second counter SAI (for example, 1) , a first PRI field (for example, y) , and a second PRI field (for example, z) . The first counter SAI may indicate a HARQ-ACK bit location of PSSCH#2 in the first PUCCH occasion (e.g., PUCCH y) . The second counter SAI may indicate a HARQ-ACK bit location of PSSCH#2 in the second PUCCH occasion (e.g., PUCCH z) . The first PRI field may indicate a PUCCH resource for HARQ-ACK of PSSCH#2 in the first PUCCH occasion (e.g., PUCCH y) . The second PRI field may indicate a PUCCH resource for HARQ-ACK of PSSCH#2 in the second PUCCH occasion (e.g., PUCCH z) .

In some aspects, a first UE may report, to a network node, HARQ-ACK on a PUCCH with multiple PUCCH occasions. For each PUCCH occasion, the first UE may report HARQ-ACK feedback accordingly. The first UE report HARQ-ACK feedback based at least in part on HARQ-ACK feedback received from any associated PSFCH occasions before a reference slot of the PUCCH occasion. For unicast, when the first UE receives, from a second UE, at least one ACK on one of the multiple PSFCH occasions before the reference slot of the PUCCH occasion, the first UE may report, to the network node, an ACK. Otherwise, the first UE may report a NACK to the network node. For groupcast option 2, when the first UE receives at least one ACK for every second UE (for example, every Rx UE) on the PSFCH occasions before the reference slot of the PUCCH occasion, the first UE may report, to the network node, an ACK. Otherwise, the first UE may report, to the network node, a NACK. For groupcast option 1, the first UE may always report, to the network node, a NACK on the PUCCH occasions, except a last PUCCH occasion. For the last PUCCH occasion, the first UE may report, to the network node, an ACK when the first UE detects an absence of a PSFCH on every PSFCH occasion before a reference slot of the last PUCCH occasion. Otherwise, the first UE may report, to the network node, a NACK.

In some aspects, for each HARQ-ACK feedback, the first UE may indicate, to the network node, whether a real ACK/NACK is reported or a virtual ACK/NACK is reported, which may assist the network node to make scheduling decisions based at least in part on a received PUCCH. Without such an indication, when a NACK is received, the network node may be unable to distinguish whether the NACK is because the first UE has not received, from the second UE, a HARQ-ACK feedback in an associated PSFCH occasion, or because the first UE fails to decode a PSSCH.

Figure 16 is a diagram illustrating an example 1600 associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 16, a network node may transmit DCI (for example, DCI 3_0) to a first UE (for example, a Tx UE) . The first UE may transmit a PSSCH transmission to a second UE (for example, Rx UE 1) . Multiple PSFCH occasions may be associated with the PSSCH transmission, and the multiple PSFCH occasions may be mapped to multiple PUCCH occasions. For example, a first PSFCH occasion associated with slot n₀ and a second PSFCH occasion associated with slot n₁ may be associated with a first PUCCH occasion associated with slot n₁ + k. A third PSFCH occasion associated with slot n₂ and a fourth PSFCH occasion associated with slot n₃ may be associated with a second PUCCH occasion associated with slot n₃ + k. The second PSFCH occasion may be a reference slot for the first PUCCH occasion. The fourth PSFCH occasion may be a reference slot for the second PUCCH occasion.

In some aspects, for unicast, the first PSFCH occasion may be associated with nothing, the second PSFCH occasion may be associated with an ACK, the third PSFCH occasion may be associated with nothing, and the fourth PSFCH occasion may be associated with nothing. In the first PUCCH occasion, the first UE may report, to the network node, an ACK since the first UE receives at least one ACK from the second UE on the reference slot of the first PUCCH occasion (i.e., 2^nd PSFCH occasion) . In the second PUCCH occasion, the first UE may report, to the network node, an ACK. Alternatively, in the first PUCCH occasion, the first UE may report, to the network node, an ACK and an indication that the ACK is a real ACK. In the second PUCCH occasion, the first UE may report, to the network node, an ACK and an indication that the ACK is a real ACK.

In some aspects, for groupcast option 2, and from the second UE, the first PSFCH occasion may be associated with an ACK. From a third UE (for example, Rx UE 2) , the first PSFCH occasion may be associated with nothing, the second PSFCH occasion may be associated with nothing, and the third PSFCH occasion may be associated with an ACK. In the first PUCCH occasion, the first UE may report, to the network node, a NACK since ACK has not been received from the third UE. In the second PUCCH occasion, the first UE may report, to the network node, an ACK since ACK has been received for every Rx UE (i.e., the second UE and the third UE) . Alternatively, in the first PUCCH occasion, the first UE may report, a NACK and an indication that the NACK is a virtual NACK. In the second PUCCH occasion, the first UE may report, to the network node, an ACK and an indication that the ACK is a real ACK.

In some aspects, for groupcast option 1, and from the second/third UE, the first PSFCH occasion may be associated with nothing, the second PSFCH occasion may be associated with nothing, the third PSFCH occasion may be associated with nothing, and the fourth PSFCH occasion may be associated with a NACK. In the first PUCCH occasion, the first UE may report, to the network node, a NACK. In the second PUCCH occasion, the first UE may report, to the network node, a NACK. Alternatively, in the first PUCCH occasion, the first UE may report, a NACK and an indication that the NACK is a virtual NACK. In the second PUCCH occasion, the first UE may report, to the network node, a NACK and an indication that the NACK is a real NACK.

Figure 17 is a flowchart illustrating an example process 1700 performed, for example, at a first UE or an apparatus of a first UE that supports a PSFCH and PUCCH timeline for multiple PSFCH channels. Example process 1700 is an example where the apparatus or the first UE (for example, UE 120a) performs operations associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As further shown in Figure 17, in some aspects, process 1700 may include transmitting, to a second UE, a PSSCH transmission (block 1710) . For example, the first UE (such as by using communication manager 140 or transmission component 1904, depicted in Figure 19) may transmit, to a second UE, a PSSCH transmission, as described above.

As further shown in Figure 17, in some aspects, process 1700 may include receiving, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions (block 1720) . For example, the first UE (such as by using communication manager 140 or reception component 1902, depicted in Figure 19) may receive, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, as described above.

As further shown in Figure 17, in some aspects, process 1700 may include transmitting, responsive to the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions (block 1730) . For example, the first UE (such as by using communication manager 140 or transmission component 1904, depicted in Figure 19) may transmit, responsive to the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions, as described above.

Process 1700 may include additional aspects, such as any single aspect or any combination of aspects described below or in connection with one or more other processes described elsewhere herein.

In a first additional aspect, each PSFCH occasion of the multiple PSFCH occasions is associated with one PUCCH occasion of the multiple PUCCH occasions.

In a second additional aspect, alone or in combination with the first aspect, a reference slot for the PUCCH transmission is a slot of the PSFCH occasion, and a PSFCH-to-HARQ feedback timing value associated with the PUCCH occasion is indicated via DCI.

In a third additional aspect, alone or in combination with one or more of the first and second aspects, one or more PSFCH occasions, of the multiple PSFCH occasions, are associated with one PUCCH occasion of the multiple PUCCH occasions.

In a fourth additional aspect, alone or in combination with one or more of the first through third aspects, the multiple PSFCH occasions are divided into multiple PSFCH occasion groups, and a PSFCH occasion group, of the multiple PSFCH occasion groups, is associated with one PUCCH occasion of the multiple PUCCH occasions.

In a fifth additional aspect, alone or in combination with one or more of the first through fourth aspects, a reference slot for the one PUCCH occasion is a slot of a last PSFCH occasion, of the multiple PSFCH occasions, within a corresponding group of PSFCH occasions, and a PSFCH-to-HARQ feedback timing value associated with the last PSFCH occasion is indicated via DCI.

In a sixth additional aspect, alone or in combination with one or more of the first through fifth aspects, the PSFCH occasion group is in accordance with a number of PSFCH occasions associated with one PSSCH, and a configured or specified number of PUCCH occasions associated with the one PSSCH.

In a seventh additional aspect, alone or in combination with one or more of the first through sixth aspects, a reference slot for the PUCCH occasion is configured via RRC signaling.

In an eighth additional aspect, alone or in combination with one or more of the first through seventh aspects, process 1700 includes receiving, via the RRC signaling, an M-bits bitmap in accordance with M PSFCH occasions being configured for the first UE, wherein M is an integer and a bit of the M-bits bitmap is associated with an individual PSFCH occasion, and the individual PSFCH occasion is associated with a reference slot for a corresponding PUCCH occasion in accordance with a value of the bit.

In a ninth additional aspect, alone or in combination with one or more of the first through eighth aspects, the PUCCH transmission indicates a Type-1 HARQ-ACK codebook in an uplink slot, and the PSSCH transmission is associated with the multiple PSFCH occasions and the multiple PUCCH occasions.

In a tenth additional aspect, alone or in combination with one or more of the first through ninth aspects, a set of occasions are associated with candidate PSSCH transmissions with corresponding PSFCH reception occasions for which the first UE is able to multiplex corresponding Type-1 HARQ-ACK codebook information in the PUCCH transmission.

In an eleventh additional aspect, alone or in combination with one or more of the first through tenth aspects, process 1700 includes transmitting the PUCCH transmission that indicates the Type-1 HARQ-ACK codebook in accordance with one or more reference slots specified or configured for the multiple PSFCH occasions.

In a twelfth additional aspect, alone or in combination with one or more of the first through eleventh aspects, process 1700 includes constructing the Type-1 HARQ-ACK codebook for a slot timing value in a set of slot timing values.

In a thirteenth additional aspect, alone or in combination with one or more of the first through twelfth aspects, process 1700 includes constructing the Type-1 HARQ-ACK codebook in accordance with: a slot that is the slot timing value away from the uplink slot that is associated with a sidelink resource pool and includes PSFCH resources, as indicated by a sidelink resource pool bitmap and a sidelink PSFCH period, and candidate PSSCH occasions associated with a PSFCH transmission occasion in the slot that is the slot timing value away from the uplink slot in accordance with a PSFCH period and specified or configured reference slots.

In a fourteenth additional aspect, alone or in combination with one or more of the first through thirteenth aspects, the candidate PSSCH occasions are added to a set of occasions for candidate PSSCH transmissions in accordance with an ascending order or a descending order of a reference slot index.

In a fifteenth additional aspect, alone or in combination with one or more of the first through fourteenth aspects, the PSSCH transmission is associated with the multiple PSFCH occasions and the multiple PUCCH occasions, and the PUCCH transmission indicates a Type-2 HARQ-ACK codebook.

In a sixteenth additional aspect, alone or in combination with one or more of the first through fifteenth aspects, process 1700 includes receiving DCI, wherein the DCI indicates multiple counter SAI fields, and each counter SAI field is associated with one PUCCH occasion of the multiple PUCCH occasions.

In a seventeenth additional aspect, alone or in combination with one or more of the first through sixteenth aspects, process 1700 includes receiving DCI, wherein the DCI indicates multiple PRI fields, and each PRI field is associated with one PUCCH occasion of the multiple PUCCH occasions.

In an eighteenth additional aspect, alone or in combination with one or more of the first through seventeenth aspects, process 1700 includes transmitting HARQ-ACK feedback on the PUCCH occasion of the multiple PUCCH occasions, wherein HARQ-ACK feedback on the PUCCH occasion is in accordance with HARQ-ACK feedback received, from the second UE, from the associated PSFCH occasions before a reference slot of the PUCCH occasion.

In a nineteenth additional aspect, alone or in combination with one or more of the first through eighteenth aspects, the PSSCH transmission is unicast, and process 1700 includes receiving, from the second UE, at least one ACK on the PSFCH occasion, of the multiple PSFCH occasions, before the reference slot of the PUCCH occasion, and transmitting an ACK.

In a twentieth additional aspect, alone or in combination with one or more of the first through nineteenth aspects, the PSSCH transmission is a groupcast associated with ACK and NACK based feedback, and process 1700 includes receiving, from each of the second UE and a third UE, at least one ACK for the second UE and the third UE on one or more PSFCH occasions, of the multiple PSFCH occasions, before the reference slot of the PUCCH occasion, and transmitting an ACK.

In a twenty-first additional aspect, alone or in combination with one or more of the first through twentieth aspects, process 1700 includes transmitting, for a groupcast associated with NACK-only feedback, a NACK on each PUCCH occasion except a last PUCCH occasion of the multiple PUCCH occasions, wherein an ACK is transmitted for the last PUCCH occasion in accordance with a detection of an absence of a PSFCH on each PSFCH occasion before a reference slot of the last PUCCH occasion.

In a twenty-second additional aspect, alone or in combination with one or more of the first through twenty-first aspects, process 1700 includes transmitting, for each HARQ-ACK feedback, an indication of whether a real ACK, a virtual ACK, a real NACK, or a virtual NACK is reported.

Figure 18 is a flowchart illustrating an example process 1800 performed, for example, at a network node or an apparatus of a network node that supports a PSFCH and PUCCH timeline for multiple PSFCH channels. Example process 1800 is an example where the apparatus or the network node (for example, network node 110) performs operations associated with a PSFCH and PUCCH timeline for multiple PSFCH channels.

As shown in Figure 18, in some aspects, process 1800 may include transmitting DCI (block 1810) . For example, the network node (such as by using communication manager 150 or transmission component 2004, depicted in Figure 20) may transmit DCI, as described above.

As further shown in Figure 18, in some aspects, process 1800 may include receiving, in accordance with a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a PSSCH transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions (block 1820) . For example, the network node (such as by using communication manager 150 or reception component 2002, depicted in Figure 20) may receive, in accordance with a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a PSSCH transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions, as described above.

Process 1800 may include additional aspects, such as any single aspect or any combination of aspects described below or in connection with one or more other processes described elsewhere herein.

In a second additional aspect, alone or in combination with the first aspect, a reference slot for the PUCCH transmission is a slot of the PSFCH occasion, and a PSFCH-to-HARQ feedback timing value associated with the PUCCH occasion is indicated via the DCI.

In a fifth additional aspect, alone or in combination with one or more of the first through fourth aspects, a reference slot for the one PUCCH occasion is a slot of a last PSFCH occasion, of the multiple PSFCH occasions, within a corresponding group of PSFCH occasions, and a PSFCH-to-HARQ feedback timing value associated with the last PSFCH occasion is indicated via the DCI.

In an eighth additional aspect, alone or in combination with one or more of the first through seventh aspects, process 1800 includes transmitting, via the RRC signaling, an M-bits bitmap in accordance with M PSFCH occasions being configured for a UE, wherein M is an integer and a bit of the M-bits bitmap is associated with an individual PSFCH occasion, and the individual PSFCH occasion is associated with a reference slot for a corresponding PUCCH occasion in accordance with a value of the bit.

In a tenth additional aspect, alone or in combination with one or more of the first through ninth aspects, process 1800 includes receiving the PUCCH transmission that indicates the Type-1 HARQ-ACK codebook in accordance with one or more reference slots specified or configured for the multiple PSFCH occasions.

In an eleventh additional aspect, alone or in combination with one or more of the first through tenth aspects, the Type-1 HARQ-ACK codebook is constructed for a slot timing value in a set of slot timing values.

In a twelfth additional aspect, alone or in combination with one or more of the first through eleventh aspects, the PSSCH transmission is associated with the multiple PSFCH occasions and the multiple PUCCH occasions, and the PUCCH transmission indicates a Type-2 HARQ-ACK codebook.

In a thirteenth additional aspect, alone or in combination with one or more of the first through twelfth aspects, the DCI indicates multiple counter SAI fields, and each counter SAI field is associated with one PUCCH occasion of the multiple PUCCH occasions.

In a fourteenth additional aspect, alone or in combination with one or more of the first through thirteenth aspects, the DCI indicates multiple PRI fields, and each PRI field is associated with one PUCCH occasion of the multiple PUCCH occasions.

In a fifteenth additional aspect, alone or in combination with one or more of the first through fourteenth aspects, process 1800 includes receiving HARQ-ACK feedback on the PUCCH occasion of the multiple PUCCH occasions, wherein HARQ-ACK feedback is reported by a first UE for the PUCCH occasion in accordance with HARQ-ACK feedback, received by the first UE from a second UE, from the associated PSFCH occasions before a reference slot of the PUCCH occasion.

In a sixteenth additional aspect, alone or in combination with one or more of the first through fifteenth aspects, process 1800 includes receiving, for each HARQ-ACK feedback, an indication of whether a real ACK, a virtual ACK, a real NACK, or a virtual NACK is reported.

Figure 19 is a diagram of an example apparatus 1900 for wireless communication that supports a PSFCH and PUCCH timeline for multiple PSFCH channels. The apparatus 1900 may be a first UE, or a first UE may include the apparatus 1900. In some aspects, the apparatus 1900 includes a reception component 1902, a transmission component 1904, and a communication manager 140, which may be in communication with one another (for example, via one or more buses) . As shown, the apparatus 1900 may communicate with another apparatus 1906 (such as a UE, a network node, or another wireless communication device) using the reception component 1902 and the transmission component 1904.

In some aspects, the apparatus 1900 may be configured to and/or operable to perform one or more operations described herein in connection with Figures 6-16. Additionally or alternatively, the apparatus 1900 may be configured to and/or operable to perform one or more processes described herein, such as process 1700 of Figure 17. In some aspects, the apparatus 1900 may include one or more components of the first UE described above in connection with Figure 2.

The reception component 1902 may receive communications, such as reference signals, control information, and/or data communications, from the apparatus 1906. The reception component 1902 may provide received communications to one or more other components of the apparatus 1900, such as the communication manager 140. In some aspects, the reception component 1902 may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples) , and may provide the processed signals to the one or more other components. In some aspects, the reception component 1902 may include one or more antennas, one or more modems, one or more demodulators, one or more MIMO detectors, one or more receive processors, one or more controllers/processors, and/or one or more memories of the first UE described above in connection with Figure 2.

The transmission component 1904 may transmit communications, such as reference signals, control information, and/or data communications, to the apparatus 1906. In some aspects, the communication manager 140 may generate communications and may transmit the generated communications to the transmission component 1904 for transmission to the apparatus 1906. In some aspects, the transmission component 1904 may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples) , and may transmit the processed signals to the apparatus 1906. In some aspects, the transmission component 1904 may include one or more antennas, one or more modems, one or more modulators, one or more transmit MIMO processors, one or more transmit processors, one or more controllers/processors, and/or one or more memories of the first UE described above in connection with Figure 2. In some aspects, the transmission component 1904 may be co-located with the reception component 1902 in one or more transceivers.

The communication manager 140 may transmit or may cause the transmission component 1904 to transmit, to a second UE, a PSSCH transmission. The communication manager 140 may receive or may cause the reception component 1902 to receive, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions. The communication manager 140 may transmit or may cause the transmission component 1904 to transmit, responsive to the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions. In some aspects, the communication manager 140 may perform one or more operations described elsewhere herein as being performed by one or more components of the communication manager 140.

The communication manager 140 may include one or more controllers/processors, and/or one or more memories of the first UE described above in connection with Figure 2. In some aspects, the communication manager 140 includes a set of components. Alternatively, the set of components may be separate and distinct from the communication manager 140. In some aspects, one or more components of the set of components may include or may be implemented within one or more controllers/processors and/or one or more memories of the first UE described above in connection with Figure 2. Additionally or alternatively, one or more components of the set of components may be implemented at least in part as software stored in one or more memories. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by one or more controllers or one or more processors to perform the functions or operations of the component.

The transmission component 1904 may transmit, to a second UE, a PSSCH transmission. The reception component 1902 may receive, from the second UE, a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions. The transmission component 1904 may transmit, responsive to the PSFCH transmission, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

Figure 20 is a diagram of an example apparatus 2000 for wireless communication that supports a PSFCH and PUCCH timeline for multiple PSFCH channels. The apparatus 2000 may be a network node, or a network node may include the apparatus 2000. In some aspects, the apparatus 2000 includes a reception component 2002, a transmission component 2004, and a communication manager 150, which may be in communication with one another (for example, via one or more buses) . As shown, the apparatus 2000 may communicate with another apparatus 2006 (such as a UE, a network node, or another wireless communication device) using the reception component 2002 and the transmission component 2004.

In some aspects, the apparatus 2000 may be configured to and/or operable to perform one or more operations described herein in connection with Figures 6-16. Additionally or alternatively, the apparatus 2000 may be configured to and/or operable to perform one or more processes described herein, such as process 1800 of Figure 18. In some aspects, the apparatus 2000 may include one or more components of the network node described above in connection with Figure 2.

The reception component 2002 may receive communications, such as reference signals, control information, and/or data communications, from the apparatus 2006. The reception component 2002 may provide received communications to one or more other components of the apparatus 2000, such as the communication manager 150. In some aspects, the reception component 2002 may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples) , and may provide the processed signals to the one or more other components. In some aspects, the reception component 2002 may include one or more antennas, one or more modems, one or more demodulators, one or more MIMO detectors, one or more receive processors, one or more controllers/processors, and/or one or more memories of the network node described above in connection with Figure 2.

The transmission component 2004 may transmit communications, such as reference signals, control information, and/or data communications, to the apparatus 2006. In some aspects, the communication manager 150 may generate communications and may transmit the generated communications to the transmission component 2004 for transmission to the apparatus 2006. In some aspects, the transmission component 2004 may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples) , and may transmit the processed signals to the apparatus 2006. In some aspects, the transmission component 2004 may include one or more antennas, one or more modems, one or more modulators, one or more transmit MIMO processors, one or more transmit processors, one or more controllers/processors, and/or one or more memories of the network node described above in connection with Figure 2. In some aspects, the transmission component 2004 may be co-located with the reception component 2002 in one or more transceivers.

The communication manager 150 may transmit or may cause the transmission component 2004 to transmit DCI. The communication manager 150 may receive or may cause the reception component 2002 to receive, in accordance with a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a PSSCH transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions. In some aspects, the communication manager 150 may perform one or more operations described elsewhere herein as being performed by one or more components of the communication manager 150.

The communication manager 150 may include one or more controllers/processors, one or more memories, one or more schedulers, and/or one or more communication units of the network node described above in connection with Figure 2. In some aspects, the communication manager 150 includes a set of components. Alternatively, the set of components may be separate and distinct from the communication manager 150. In some aspects, one or more components of the set of components may include or may be implemented within one or more controllers/processors, one or more memories, one or more schedulers, and/or one or more communication units of the network node described above in connection with Figure 2. Additionally or alternatively, one or more components of the set of components may be implemented at least in part as software stored in one or more memories. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by one or more controllers or one or more processors to perform the functions or operations of the component.

The transmission component 2004 may transmit DCI. The reception component 2002 may receive, in accordance with a PSFCH transmission during a PSFCH occasion of multiple PSFCH occasions, a PUCCH transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a PSSCH transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

The number and arrangement of components shown in Figure 20 are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in Figure 20. Furthermore, two or more components shown in Figure 20 may be implemented within a single component, or a single component shown in Figure 20 may be implemented as multiple, distributed components. Additionally or alternatively, a set of (one or more) components shown in Figure 20 may perform one or more functions described as being performed by another set of components shown in Figure 20.

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

Aspect 1: A method of wireless communication performed at a first user equipment (UE) , comprising: transmitting, to a second UE, a physical sidelink shared channel (PSSCH) transmission; receiving, from the second UE, a physical sidelink feedback channel (PSFCH) transmission during a PSFCH occasion of multiple PSFCH occasions; and transmitting, responsive to the PSFCH transmission, a physical uplink control channel (PUCCH) transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

Aspect 2: The method of Aspect 1, wherein each PSFCH occasion of the multiple PSFCH occasions is associated with one PUCCH occasion of the multiple PUCCH occasions.

Aspect 3: The method of any of Aspects 1-2, wherein a reference slot for the PUCCH transmission is a slot of the PSFCH occasion, and a PSFCH to hybrid automatic repeat request (HARQ) feedback timing value associated with the PUCCH occasion is indicated via downlink control information (DCI) .

Aspect 4: The method of any of Aspects 1-3, wherein one or more PSFCH occasions, of the multiple PSFCH occasions, are associated with one PUCCH occasion of the multiple PUCCH occasions.

Aspect 5: The method of Aspect 4, wherein the multiple PSFCH occasions are divided into multiple PSFCH occasion groups, and a PSFCH occasion group, of the multiple PSFCH occasion groups, is associated with one PUCCH occasion of the multiple PUCCH occasions.

Aspect 6: The method of Aspect 5, wherein a reference slot for the one PUCCH occasion is a slot of a last PSFCH occasion, of the multiple PSFCH occasions, within a corresponding group of PSFCH occasions, and a PSFCH to hybrid automatic repeat request (HARQ) feedback timing value associated with the last PSFCH occasion is indicated via downlink control information (DCI) .

Aspect 7: The method of Aspect 5, wherein the PSFCH occasion group is in accordance with a number of PSFCH occasions associated with one PSSCH, and a configured or specified number of PUCCH occasions associated with the one PSSCH.

Aspect 8: The method of any of Aspects 1-7, wherein a reference slot for the PUCCH occasion is configured via radio resource control (RRC) signaling.

Aspect 9: The method of Aspect 8, further comprising: receiving, via the RRC signaling, an M-bits bitmap in accordance with M PSFCH occasions being configured for the first UE, wherein M is an integer and a bit of the M-bits bitmap is associated with an individual PSFCH occasion, and the individual PSFCH occasion is associated with a reference slot for a corresponding PUCCH occasion in accordance with a value of the bit.

Aspect 10: The method of any of Aspects 1-9, wherein the PUCCH transmission indicates a Type-1 hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook in an uplink slot, and the PSSCH transmission is associated with the multiple PSFCH occasions and the multiple PUCCH occasions.

Aspect 11: The method of Aspect 10, wherein a set of occasions are associated with candidate PSSCH transmissions with corresponding PSFCH reception occasions for which the first UE is able to multiplex corresponding Type-1 HARQ-ACK codebook information in the PUCCH transmission.

Aspect 12: The method of Aspect 10, wherein transmitting the PUCCH transmission that indicates the Type-1 HARQ-ACK codebook is in accordance with one or more reference slots specified or configured for the multiple PSFCH occasions.

Aspect 13: The method of Aspect 10, further comprising: constructing the Type-1 HARQ-ACK codebook for a slot timing value in a set of slot timing values.

Aspect 14: The method of Aspect 13, wherein constructing the Type-1 HARQ-ACK codebook is in accordance with: a slot that is the slot timing value away from the uplink slot that is associated with a sidelink resource pool and includes PSFCH resources, as indicated by a sidelink resource pool bitmap and a sidelink PSFCH period; and candidate PSSCH occasions associated with a PSFCH transmission occasion in the slot that is the slot timing value away from the uplink slot in accordance with a PSFCH period and specified or configured reference slots.

Aspect 15: The method of Aspect 14, wherein the candidate PSSCH occasions are added to a set of occasions for candidate PSSCH transmissions in accordance with an ascending order or a descending order of a reference slot index.

Aspect 16: The method of any of Aspects 1-15, wherein the PSSCH transmission is associated with the multiple PSFCH occasions and the multiple PUCCH occasions, and the PUCCH transmission indicates a Type-2 hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook.

Aspect 17: The method of Aspect 16, further comprising: receiving downlink control information (DCI) , wherein the DCI indicates multiple counter sidelink assignment index (SAI) fields, and each counter SAI field is associated with one PUCCH occasion of the multiple PUCCH occasions.

Aspect 18: The method of Aspect 16, further comprising: receiving downlink control information (DCI) , wherein the DCI indicates multiple PUCCH resource indicator (PRI) fields, and each PRI field is associated with one PUCCH occasion of the multiple PUCCH occasions.

Aspect 19: The method of any of Aspects 1-18, wherein transmitting the PUCCH transmission comprises transmitting hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback on the PUCCH occasion of the multiple PUCCH occasions, wherein HARQ-ACK feedback on the PUCCH occasion is in accordance with HARQ-ACK feedback received, from the second UE, from the associated PSFCH occasions before a reference slot of the PUCCH occasion.

Aspect 20: The method of Aspect 19, wherein the PSSCH transmission is unicast, and further comprising: receiving, from the second UE, at least one acknowledgement (ACK) on the PSFCH occasion, of the multiple PSFCH occasions, before the reference slot of the PUCCH occasion, wherein transmitting the HARQ-ACK feedback comprises transmitting an ACK.

Aspect 21: The method of Aspect 19, wherein the PSSCH transmission is a groupcast associated with ACK and negative acknowledgement (NACK) based feedback, and further comprising: receiving, from each of the second UE and a third UE, at least one acknowledgement (ACK) for the second UE and the third UE on one or more PSFCH occasions, of the multiple PSFCH occasions, before the reference slot of the PUCCH occasion, wherein transmitting the HARQ-ACK feedback comprises transmitting an ACK.

Aspect 22: The method of Aspect 19, wherein transmitting the HARQ-ACK feedback, for a groupcast associated with NACK-only feedback, comprises transmitting a negative acknowledgement (NACK) on each PUCCH occasion except a last PUCCH occasion of the multiple PUCCH occasions, wherein an acknowledgement (ACK) is transmitted for the last PUCCH occasion in accordance with a detection of an absence of a PSFCH on each PSFCH occasion before a reference slot of the last PUCCH occasion.

Aspect 23: The method of any of Aspects 1-22, wherein transmitting the PUCCH transmission comprises transmitting, for each hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback, an indication of whether a real acknowledgement (ACK) , a virtual ACK, a real negative acknowledgement (NACK) , or a virtual NACK is reported.

Aspect 24: A method of wireless communication performed at a network node, comprising: transmitting downlink control information (DCI) ; and receiving, in accordance with a physical sidelink feedback channel (PSFCH) transmission during a PSFCH occasion of multiple PSFCH occasions, a physical uplink control channel (PUCCH) transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a physical sidelink shared channel (PSSCH) transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.

Aspect 25: The method of Aspect 24, wherein each PSFCH occasion of the multiple PSFCH occasions is associated with one PUCCH occasion of the multiple PUCCH occasions.

Aspect 26: The method of any of Aspects 24-25, wherein a reference slot for the PUCCH transmission is a slot of the PSFCH occasion, and a PSFCH to hybrid automatic repeat request (HARQ) feedback timing value associated with the PUCCH occasion is indicated via the DCI.

Aspect 27: The method of any of Aspects 24-26, wherein one or more PSFCH occasions, of the multiple PSFCH occasions, are associated with one PUCCH occasion of the multiple PUCCH occasions.

Aspect 28: The method of Aspect 27, wherein the multiple PSFCH occasions are divided into multiple PSFCH occasion groups, and a PSFCH occasion group, of the multiple PSFCH occasion groups, is associated with one PUCCH occasion of the multiple PUCCH occasions.

Aspect 29: The method of Aspect 28, wherein a reference slot for the one PUCCH occasion is a slot of a last PSFCH occasion, of the multiple PSFCH occasions, within a corresponding group of PSFCH occasions, and a PSFCH to hybrid automatic repeat request (HARQ) feedback timing value associated with the last PSFCH occasion is indicated via the DCI.

Aspect 30: The method of Aspect 28, wherein the PSFCH occasion group is in accordance with a number of PSFCH occasions associated with one PSSCH, and a configured or specified number of PUCCH occasions associated with the one PSSCH.

Aspect 31: The method of any of Aspects 24-30, wherein a reference slot for the PUCCH occasion is configured via radio resource control (RRC) signaling.

Aspect 32: The method of Aspect 31, further comprising: transmitting, via the RRC signaling, an M-bits bitmap in accordance with M PSFCH occasions being configured for a user equipment (UE) , wherein M is an integer and a bit of the M-bits bitmap is associated with an individual PSFCH occasion, and the individual PSFCH occasion is associated with a reference slot for a corresponding PUCCH occasion in accordance with a value of the bit.

Aspect 33: The method of any of Aspects 24-32, wherein the PUCCH transmission indicates a Type-1 hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook in an uplink slot, and the PSSCH transmission is associated with the multiple PSFCH occasions and the multiple PUCCH occasions.

Aspect 34: The method of Aspect 33, wherein receiving the PUCCH transmission that indicates the Type-1 HARQ-ACK codebook is in accordance with one or more reference slots specified or configured for the multiple PSFCH occasions.

Aspect 35: The method of Aspect 33, wherein the Type-1 HARQ-ACK codebook is constructed for a slot timing value in a set of slot timing values.

Aspect 36: The method of any of Aspects 24-35, wherein the PSSCH transmission is associated with the multiple PSFCH occasions and the multiple PUCCH occasions, and the PUCCH transmission indicates a Type-2 hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook.

Aspect 37: The method of Aspect 36, wherein the DCI indicates multiple counter sidelink assignment index (SAI) fields, and each counter SAI field is associated with one PUCCH occasion of the multiple PUCCH occasions.

Aspect 38: The method of Aspect 36, wherein the DCI indicates multiple PUCCH resource indicator (PRI) fields, and each PRI field is associated with one PUCCH occasion of the multiple PUCCH occasions.

Aspect 39: The method of any of Aspects 24-38, wherein receiving the PUCCH transmission comprises receiving hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback on the PUCCH occasion of the multiple PUCCH occasions, wherein HARQ-ACK feedback is reported by a first user equipment (UE) for the PUCCH occasion in accordance with HARQ-ACK feedback, received by the first UE from a second UE, from the associated PSFCH occasions before a reference slot of the PUCCH occasion.

Aspect 40: The method of any of Aspects 24-39, wherein receiving the PUCCH transmission comprises receiving, for each hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback, an indication of whether a real acknowledgement (ACK) , a virtual ACK, a real negative acknowledgement (NACK) , or a virtual NACK is reported.

Aspect 41: An apparatus for wireless communication at a device, the apparatus comprising one or more processors; one or more memories coupled with the one or more processors; and instructions stored in the one or more memories and executable by the one or more processors to cause the apparatus to perform the method of one or more of Aspects 1-23.

Aspect 42: An apparatus for wireless communication at a device, the apparatus comprising one or more memories and one or more processors coupled to the one or more memories, the one or more processors configured to cause the device to perform the method of one or more of Aspects 1-23.

Aspect 43: An apparatus for wireless communication, the apparatus comprising at least one means for performing the method of one or more of Aspects 1-23.

Aspect 44: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by one or more processors to perform the method of one or more of Aspects 1-23.

Aspect 45: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more of Aspects 1-23.

Aspect 46: A device for wireless communication, the device comprising a processing system that includes one or more processors and one or more memories coupled with the one or more processors, the processing system configured to cause the device to perform the method of one or more of Aspects 1-23.

Aspect 47: An apparatus for wireless communication at a device, the apparatus comprising one or more processors; one or more memories coupled with the one or more processors; and instructions stored in the one or more memories and executable by the one or more processors to cause the apparatus to perform the method of one or more of Aspects 24-40.

Aspect 48: An apparatus for wireless communication at a device, the apparatus comprising one or more memories and one or more processors coupled to the one or more memories, the one or more processors configured to cause the device to perform the method of one or more of Aspects 24-40.

Aspect 49: An apparatus for wireless communication, the apparatus comprising at least one means for performing the method of one or more of Aspects 24-40.

Aspect 50: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by one or more processors to perform the method of one or more of Aspects 24-40.

Aspect 51: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more of Aspects 24-40.

Aspect 52: A device for wireless communication, the device comprising a processing system that includes one or more processors and one or more memories coupled with the one or more processors, the processing system configured to cause the device to perform the method of one or more of Aspects 24-40.

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

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

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

As used herein, the term “determine” or “determining” encompasses a wide variety of actions and, therefore, “determining” can include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, a database or another data structure) , identifying, inferring, ascertaining, measuring, and the like. Also, “determining” can include receiving (such as receiving information or receiving an indication) , accessing (such as accessing data stored in memory) , transmitting (such as transmitting information) and the like. Also, “determining” can include resolving, selecting, obtaining, choosing, establishing and other such similar actions. The term “identify” or “identifying” also encompasses a wide variety of actions and, therefore, “identifying” can include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, a database or another data structure) , inferring, ascertaining, measuring, and the like. Also, “identifying” can include receiving (such as receiving information or receiving an indication) , accessing (such as accessing data stored in memory) , transmitting (such as transmitting information) and the like. Also, “identifying” can include resolving, selecting, obtaining, choosing, establishing and other such similar actions.

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

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items and may be used interchangeably with “one or more. ” Further, as used herein, the article “the” is intended to include one or more items referenced in connection with the article “the” and may be used interchangeably with “the one or more. ” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items and may be used interchangeably with “one or more. ” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used herein, the terms “has, ” “have, ” “having, ” and similar terms are intended to be open-ended terms that do not limit an element that they modify (for example, an element “having” A may also have B) . Further, as used herein, “based on” is intended to be interpreted in the inclusive sense, unless otherwise explicitly indicated. For example, “based on” may be used interchangeably with “based at least in part on, ” “associated with” , or “in accordance with” unless otherwise explicitly indicated. Specifically, unless a phrase refers to “based on only ‘a, ’ ” or the equivalent in context, whatever it is that is “based on ‘a, ’ ” or “based at least in part on ‘a, ’ ” may be based on “a” alone or based on a combination of “a” and one or more other factors, conditions or information. . Also, as used herein, the term “or” is intended to be inclusive when used in a series and may be used interchangeably with “and/or, ” unless explicitly stated otherwise (for example, if used in combination with “either” or “only one of” ) .

Claims

An apparatus for wireless communication at a first user equipment (UE) , comprising:

one or more memories storing processor-readable code; and

one or more processors coupled with the one or more memories, at least one of the one or more processors operable to cause the first UE to:

transmit, to a second UE, a physical sidelink shared channel (PSSCH) transmission;

receive, from the second UE, a physical sidelink feedback channel (PSFCH) transmission during a PSFCH occasion of multiple PSFCH occasions; and

transmit, responsive to the PSFCH transmission, a physical uplink control channel (PUCCH) transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.
The apparatus of claim 1, wherein each PSFCH occasion of the multiple PSFCH occasions is associated with one PUCCH occasion of the multiple PUCCH occasions.
The apparatus of claim 1, wherein a reference slot for the PUCCH transmission is a slot of the PSFCH occasion, and a PSFCH to hybrid automatic repeat request (HARQ) feedback timing value associated with the PUCCH occasion is indicated via downlink control information (DCI) .
The apparatus of claim 1, wherein one or more PSFCH occasions, of the multiple PSFCH occasions, are associated with one PUCCH occasion of the multiple PUCCH occasions.
The apparatus of claim 4, wherein the multiple PSFCH occasions are divided into multiple PSFCH occasion groups, and a PSFCH occasion group, of the multiple PSFCH occasion groups, is associated with one PUCCH occasion of the multiple PUCCH occasions.
The apparatus of claim 5, wherein a reference slot for the one PUCCH occasion is a slot of a last PSFCH occasion, of the multiple PSFCH occasions, within a corresponding group of PSFCH occasions, and a PSFCH to hybrid automatic repeat request (HARQ) feedback timing value associated with the last PSFCH occasion is indicated via downlink control information (DCI) .
The apparatus of claim 5, wherein the PSFCH occasion group is in accordance with a number of PSFCH occasions associated with one PSSCH, and a configured or specified number of PUCCH occasions associated with the one PSSCH.
The apparatus of claim 1, wherein a reference slot for the PUCCH occasion is configured via radio resource control (RRC) signaling.
The apparatus of claim 8, wherein at least one processor of the one or more processors is configured to:

receive, via the RRC signaling, an M-bits bitmap in accordance with M PSFCH occasions being configured for the first UE, wherein M is an integer and a bit of the M-bits bitmap is associated with an individual PSFCH occasion, and the individual PSFCH occasion is associated with a reference slot for a corresponding PUCCH occasion in accordance with a value of the bit.
The apparatus of claim 1, wherein the PUCCH transmission indicates a Type-1 hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook in an uplink slot, and the PSSCH transmission is associated with the multiple PSFCH occasions and the multiple PUCCH occasions.
The apparatus of claim 10, wherein a set of occasions are associated with candidate PSSCH transmissions with corresponding PSFCH reception occasions for which the first UE is able to multiplex corresponding Type-1 HARQ-ACK codebook information in the PUCCH transmission.
The apparatus of claim 10, wherein at least one processor of the one or more processors is configured to transmit the PUCCH transmission that indicates the Type-1 HARQ-ACK codebook in accordance with one or more reference slots specified or configured for the multiple PSFCH occasions.
The apparatus of claim 10, wherein at least one processor of the one or more processors is configured to:

construct the Type-1 HARQ-ACK codebook for a slot timing value in a set of slot timing values.
The apparatus of claim 13, wherein at least one processor of the one or more processors is configured to construct the Type-1 HARQ-ACK codebook in accordance with:

a slot that is the slot timing value away from the uplink slot that is associated with a sidelink resource pool and includes PSFCH resources, as indicated by a sidelink resource pool bitmap and a sidelink PSFCH period; and

candidate PSSCH occasions associated with a PSFCH transmission occasion in the slot that is the slot timing value away from the uplink slot in accordance with a PSFCH period and specified or configured reference slots.
The apparatus of claim 14, wherein the candidate PSSCH occasions are added to a set of occasions for candidate PSSCH transmissions in accordance with an ascending order or a descending order of a reference slot index.
The apparatus of claim 1, wherein the PSSCH transmission is associated with the multiple PSFCH occasions and the multiple PUCCH occasions, and the PUCCH transmission indicates a Type-2 hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook.
The apparatus of claim 16, wherein at least one processor of the one or more processors is configured to:

receive downlink control information (DCI) , wherein the DCI indicates multiple counter sidelink assignment index (SAI) fields, and each counter SAI field is associated with one PUCCH occasion of the multiple PUCCH occasions.
The apparatus of claim 16, wherein at least one processor of the one or more processors is configured to:

receive downlink control information (DCI) , wherein the DCI indicates multiple PUCCH resource indicator (PRI) fields, and each PRI field is associated with one PUCCH occasion of the multiple PUCCH occasions.
The apparatus of claim 1, wherein at least one processor of the one or more processors, when transmitting the PUCCH transmission, is configured to:

transmit hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback on the PUCCH occasion of the multiple PUCCH occasions, wherein HARQ-ACK feedback on the PUCCH occasion is in accordance with HARQ-ACK feedback received, from the second UE, from the associated PSFCH occasions before a reference slot of the PUCCH occasion.
The apparatus of claim 19, wherein the PSSCH transmission is unicast, and wherein at least one processor of the one or more processors is configured to:

receive, from the second UE, at least one acknowledgement (ACK) on the PSFCH occasion, of the multiple PSFCH occasions, before the reference slot of the PUCCH occasion,

wherein at least one processor of the one or more processors, when transmitting the HARQ-ACK feedback, is configured to transmit an ACK.
The apparatus of claim 19, wherein the PSSCH transmission is a groupcast associated with ACK and negative acknowledgement (NACK) based feedback, and wherein at least one processor of the one or more processors is configured to:

receive, from each of the second UE and a third UE, at least one acknowledgement (ACK) for the second UE and the third UE on one or more PSFCH occasions, of the multiple PSFCH occasions, before the reference slot of the PUCCH occasion,

wherein at least one processor of the one or more processors, when transmitting the HARQ-ACK feedback, is configured to transmit an ACK.
The apparatus of claim 19, wherein at least one processor of the one or more processors, when transmitting the HARQ-ACK feedback, for a groupcast associated with NACK-only feedback, is configured to:

transmit a negative acknowledgement (NACK) on each PUCCH occasion except a last PUCCH occasion of the multiple PUCCH occasions, wherein an acknowledgement (ACK) is transmitted for the last PUCCH occasion in accordance with a detection of an absence of a PSFCH on each PSFCH occasion before a reference slot of the last PUCCH occasion.
The apparatus of claim 1, wherein at least one processor of the one or more processors, when transmitting the PUCCH transmission, is configured to:

transmit, for each hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback, an indication of whether a real acknowledgement (ACK) , a virtual ACK, a real negative acknowledgement (NACK) , or a virtual NACK is reported.
An apparatus for wireless communication at a network node, comprising:

one or more memories storing processor-readable code; and

one or more processors coupled with the one or more memories, at least one of the one or more processors operable to cause the network node to:

transmit downlink control information (DCI) ; and

receive, in accordance with a physical sidelink feedback channel (PSFCH) transmission during a PSFCH occasion of multiple PSFCH occasions, a physical uplink control channel (PUCCH) transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a physical sidelink shared channel (PSSCH) transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.
The apparatus of claim 24, wherein at least one processor of the one or more processors is configured to:

transmit, via radio resource control (RRC) signaling, an M-bits bitmap in accordance with M PSFCH occasions being configured for a user equipment (UE) , wherein M is an integer and a bit of the M-bits bitmap is associated with an individual PSFCH occasion, and the individual PSFCH occasion is associated with a reference slot for a corresponding PUCCH occasion in accordance with a value of the bit.
The apparatus of claim 24, wherein at least one processor of the one or more processors is configured to:

receive the PUCCH transmission that indicates a Type-1 hybrid automatic repeat request acknowledgement (HARQ-ACK) codebook in accordance with one or more reference slots specified or configured for the multiple PSFCH occasions.
The apparatus of claim 24, wherein at least one processor of the one or more processors, when receiving the PUCCH transmission, is configured to:

receive hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback on the PUCCH occasion of the multiple PUCCH occasions, wherein HARQ-ACK feedback is reported by a first user equipment (UE) for the PUCCH occasion in accordance with HARQ-ACK feedback, received by the first UE from a second UE, from the associated PSFCH occasions before a reference slot of the PUCCH occasion.
The apparatus of claim 24, wherein at least one processor of the one or more processors, when receiving the PUCCH transmission, is configured to:

receive, for each hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback, an indication of whether a real acknowledgement (ACK) , a virtual ACK, a real negative acknowledgement (NACK) , or a virtual NACK is reported.
A method of wireless communication performed at a first user equipment (UE) , comprising:

transmitting, to a second UE, a physical sidelink shared channel (PSSCH) transmission;

receiving, from the second UE, a physical sidelink feedback channel (PSFCH) transmission during a PSFCH occasion of multiple PSFCH occasions; and

transmitting, responsive to the PSFCH transmission, a physical uplink control channel (PUCCH) transmission during a PUCCH occasion of multiple PUCCH occasions, and the PSSCH transmission is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.
A method of wireless communication performed at a network node, comprising:

transmitting downlink control information (DCI) ; and

receiving, in accordance with a physical sidelink feedback channel (PSFCH) transmission during a PSFCH occasion of multiple PSFCH occasions, a physical uplink control channel (PUCCH) transmission during a PUCCH occasion of multiple PUCCH occasions, wherein a physical sidelink shared channel (PSSCH) transmission in accordance with the DCI is associated with the multiple PUCCH occasions in accordance with the PSSCH transmission being associated with multiple PSFCH occasions.