Sending feedback using time slots based at least in part on set of timelines

Abstract

Aspects of the present disclosure generally relate to wireless communications. In some aspects, a first user equipment (UE) can receive a sidelink transmission associated with a broadcast type from a second UE. The first UE can transmit hybrid automatic repeat request (HARQ) feedback to the second UE based at least in part on the sidelink transmission, where a slot for transmitting the HARQ feedback is based at least in part on a set of HARQ timelines associated with the broadcast type, and where the set of HARQ timelines is included in a plurality of HARQ timeline sets configured for a sidelink. Numerous other aspects are described.

Description

Technical Field

[0001] Aspects of the present disclosure relate generally to wireless communications, and to techniques and apparatus for sending feedback using time slots based at least in part on a set of timelines. Background Art

[0002] Wireless communication systems are widely deployed to provide a variety of telecommunication services, such as telephony, video, data, messaging, and broadcasting. Typical wireless communication systems may employ multiple access technologies that can support communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). 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).

[0003] A wireless network may include one or more network nodes that support communications for wireless communication devices, such as user equipment (UE) or multiple UEs. A UE may communicate with a network node via downlink communications and uplink communications. A "downlink" (or "DL") refers to a communication link from a network node to a UE, and an "uplink" (or "UL") refers to a communication link from a UE to a network node. Some wireless networks may support device-to-device communications, such as via a local link (e.g., a side link (SL), a wireless local area network (WLAN) link, and / or a wireless personal area network (WPAN) link, among other examples).

[0004] The above-mentioned multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different UEs to communicate at a city, country, region and / or global level. New Radio (NR) (which may be referred to as 5G) is an enhancement set to the LTE mobile standard promulgated by 3GPP. NR is designed to better support mobile broadband Internet access by using orthogonal frequency division multiplexing (OFDM) (CP-OFDM) with a cyclic prefix (CP) on the downlink, using CP-OFDM and / or single carrier frequency division multiplexing (SC-FDM) (also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) on the uplink, and supporting beamforming, multiple input multiple output (MIMO) antenna technology and carrier aggregation to improve spectrum efficiency, reduce costs, improve services, utilize new spectrum, and better integrate with other open standards. As the demand for mobile broadband access continues to increase, further improvements in LTE, NR and other radio access technologies remain useful. Summary of the invention

[0005] In some specific implementations, an apparatus for wireless communication at a first user equipment (UE) includes: a memory; and one or more processors coupled to the memory, the one or more processors configured to: receive a sidelink transmission associated with a broadcast type from a second UE; and send a hybrid automatic repeat request (HARQ) feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink.

[0006] In some specific implementations, an apparatus for performing wireless communications at a first UE includes: a memory; and one or more processors coupled to the memory, the one or more processors configured to: receive sidelink control information (SCI) from a second UE; receive a sidelink transmission from the second UE; and send HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink.

[0007] In some specific implementations, a method of wireless communication performed by a first UE includes: receiving a sidelink transmission associated with a broadcast type from a second UE; and sending HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink.

[0008] In some specific implementations, a method of wireless communication performed by a first UE includes: receiving an SCI from a second UE; receiving a sidelink transmission from the second UE; and sending HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink.

[0009] In some specific implementations, a non-transitory computer-readable medium storing an instruction set for wireless communication includes one or more instructions that, when executed by one or more processors of a first UE, cause the first UE to: receive a sidelink transmission associated with a broadcast type from a second UE; and send HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink.

[0010] In some specific implementations, a non-transitory computer-readable medium storing an instruction set for wireless communication includes one or more instructions that, when executed by one or more processors of a first UE, cause the first UE to: receive an SCI from a second UE; receive a sidelink transmission from the second UE; and send HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink.

[0011] In some specific implementations, a first device for wireless communication includes: a component for receiving a sidelink transmission associated with a broadcast type from a second device; and a component for sending HARQ feedback to the second device based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink.

[0012] In some specific embodiments, a first device for wireless communication includes: a component for receiving an SCI from a second device; a component for receiving a sidelink transmission from the second device; and a component for sending HARQ feedback to the second device based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink.

[0013] The various aspects generally include methods, apparatus, systems, computer program products, non-transitory computer-readable media, user equipment, base stations, network entities, network nodes, wireless communication devices and / or processing systems as fully described herein with reference to the drawings and description and as illustrated in the drawings and description.

[0014] The features and technical advantages of examples according to the present disclosure have been outlined quite extensively above so that the following specific embodiments may be better understood. Additional features and advantages will be described below. The disclosed concepts and specific examples may be easily used as a basis for modifying or designing other structures for achieving the same purpose of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. The characteristics of the concepts disclosed herein, both in terms of their organization and method of operation, and the associated advantages will be better understood by considering the following description in conjunction with the accompanying drawings. Each of the figures in the accompanying drawings is provided for the purpose of illustration and description and not as a definition of limitations to the claims.

[0015] Although various aspects are described in the present disclosure by illustrating some examples, it will be understood by those skilled in the art that such aspects can be implemented in many different arrangements and scenarios. The technology described herein can be implemented using different platform types, devices, systems, shapes, sizes and / or packaging arrangements. For example, some aspects can be implemented via integrated chip implementations or other devices based on non-module components (e.g., end-user devices, vehicles, communication equipment, computing equipment, industrial equipment, retail / shopping equipment, medical equipment and / or artificial intelligence devices). Various aspects can be implemented in chip-level components, modular components, non-modular components, non-chip-level components, device-level components and / or system-level components. The equipment incorporating the various aspects and features described may include additional components and features for implementing and practicing the various aspects claimed and described. For example, the transmission and reception of wireless signals may include one or more components (e.g., hardware components, including antennas, radio frequency chains, power amplifiers, modulators, buffers, processors, interleavers, adders and / or summers) for analog and digital purposes. The various aspects described herein are intended to be practiced in various devices, components, systems, distributed arrangements and / or end-user devices of various sizes, shapes and configurations. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to fully understand the above-mentioned features of the present disclosure, a more specific description of the invention briefly summarized above can be obtained by referring to various aspects (some of which are illustrated in the accompanying drawings). However, it should be noted that the accompanying drawings only illustrate certain typical aspects of the present disclosure and are therefore not to be considered as limiting the scope thereof, as the specification may admit of other equally effective aspects. The same reference numerals in different drawings may identify the same or similar elements.

[0017] Figure 1 is a diagram illustrating an example of a wireless network according to the present disclosure.

[0018] Figure 2 is a diagram illustrating an example of communication between a network node and a user equipment (UE) in a wireless network according to the present disclosure.

[0019] Figure 3 is a diagram illustrating an example of side link transmission according to the present disclosure.

[0020] Figure 4 is a diagram illustrating an example of multiple time-domain physical sidelink feedback channel (PSFCH) opportunities according to the present disclosure.

[0021] Figures 5 to 12 is a diagram illustrating an example associated with sending feedback using time slots based at least in part on a set of timelines according to the present disclosure.

[0022] Figure 13 to Figure 14 is a diagram illustrating example procedures associated with sending feedback using time slots based at least in part on a set of timelines in accordance with the present disclosure.

[0023] Fig.15 is a diagram of an example apparatus for wireless communications according to the present disclosure. DETAILED DESCRIPTION

[0024] The various aspects of the present disclosure are described more fully below with reference to the accompanying drawings. However, the present disclosure can be embodied in many different forms, and should not be interpreted as being limited to any specific structure or function presented throughout the present disclosure. On the contrary, these aspects are provided so that the present disclosure will be thorough and complete, and the scope of the present disclosure will be fully conveyed to those skilled in the art. It should be understood by those skilled in the art that the scope of the present disclosure is intended to cover any aspect of the disclosure disclosed herein, whether it is implemented independently or in combination with any other aspect of the present disclosure. For example, any number of aspects set forth herein may be used to implement a device or practice method. In addition, the scope of the present disclosure is intended to cover such a device or method that is practiced using other structures, functionality, or structure and functionality in addition to or different from the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of the claims.

[0025] Several aspects of telecommunication systems will now be presented with reference to various devices and techniques. These devices and techniques will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as "elements"). These elements can be implemented using hardware, software, or a combination thereof. Whether these elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0026] Although various aspects may be described herein using terms generally associated with 5G or new radio (NR) radio access technologies (RATs), various aspects of the present disclosure may be applicable to other RATs, such as 3G RATs, 4G RATs, and / or post-5G RATs (e.g., 6G).

[0027] Figure 1 1 is a diagram illustrating an example of a wireless network 100 according to the present disclosure. The wireless network 100 may be a 5G (e.g., NR) network and / or a 4G (e.g., Long Term Evolution (LTE)) network, or may include elements of a 5G (e.g., NR) network and / or elements of a 4G (e.g., Long Term Evolution (LTE)) network, as well as other examples. The wireless network 100 may include one or more network nodes 110 (shown as network node 110a, network node 110b, network node 110c, and network node 110d), user equipment (UE) 120 or multiple UEs 120 (shown as UE 120a, UE 120b, UE 120c, UE 120d, and UE 120e), and / or other entities. The network node 110 is a network node that communicates with the UE 120. As shown in the figure, the network node 110 may include one or more network nodes. For example, the network node 110 may be a converged network node, which means that the converged network node is configured to utilize a radio protocol stack that is physically or logically integrated within a single radio access network (RAN) node (e.g., within a single device or unit). As another example, the network node 110 may be a decomposed network node (sometimes referred to as a decomposed base station), which means that the network node 110 is configured to utilize a protocol stack that is physically or logically distributed between 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)).

[0028] In some examples, the network node 110 is or includes a network node that communicates with the UE 120 via a radio access link, such as an RU. In some examples, the 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, the network node 110 is or includes a network node that communicates with other network nodes 110 via a midhaul link or communicates with the core network via a backhaul link, such as a CU. In some examples, the network node 110 (such as an aggregated network node 110 or a decomposed network node 110) may include multiple network nodes, such as one or more RUs, one or more CUs, and / or one or more DUs. The network node 110 may include, for example, an NR base station, an LTE base station, a Node B, an eNB (e.g., in 4G), a gNB (e.g., in 5G), an access point, a transmit receive point (TRP), a DU, a RU, a CU, a mobility element of a network, a core network node, a network element, a network equipment, a RAN node, or a combination thereof. In some examples, network nodes 110 may be interconnected to each other or to one or more other network nodes 110 in wireless network 100 via various types of fronthaul, midhaul, and / or backhaul interfaces, such as direct physical connections, air interfaces, or virtual networks, using any suitable transport network.

[0029] In some examples, the network node 110 may provide communication coverage for a particular geographic area. In the Third Generation Partnership Project (3GPP), the term "cell" may refer to the coverage area of ​​the network node 110 and / or the network node subsystem serving the coverage area, depending on the context in which the term is used. The network node 110 may provide communication coverage for a macro cell, a pico cell, a femto cell, and / or another type of cell. A macro cell may cover a relatively large geographic area (e.g., a radius of several kilometers) and may allow unrestricted access by a UE 120 with a service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by a UE 120 with a service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by a UE 120 associated with the femto cell (e.g., a UE 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. The network node 110 for a femto cell may be referred to as a femto network node or a home network node. Figure 1In the example shown in , network node 110a may be a macro network node for macro cell 102a, network node 110b may be a pico network node for pico cell 102b, and network node 110c may be a femto network node for femto cell 102c. A network node may support one or more (e.g., three) cells. In some examples, a cell may not necessarily be stationary, and the geographic area of ​​a cell may move depending on the location of a mobile network node 110 (e.g., a mobile network node).

[0030] In some aspects, the term "base station" or "network node" may refer to an aggregated base station, a decomposed base station, an integrated access and backhaul (IAB) node, a relay node, or one or more components thereof. For example, in some aspects, a "base station" or "network node" may refer to a CU, a DU, a RU, a near real-time (near RT) RAN intelligent controller (RIC), or a non-real-time (non-RT) RIC, or a combination thereof. In some aspects, the term "base station" or "network node" may refer to a device configured to perform one or more functions (such as those described herein in conjunction with the network node 110). In some aspects, the term "base station" or "network node" may refer to a plurality of devices configured to perform one or more functions. For example, in some distributed systems, each of a number of different devices (which may be located in the same geographic location or in different geographic locations) may be configured to perform at least a portion of a function, or to repeat the execution of at least a portion of the function, and the term "base station" or "network node" may refer to any one or more of these different devices. In some aspects, the term "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 term "base station" or "network node" may refer to one of the base station functions but not the other. In this way, a single device may include more than one base station.

[0031] The wireless network 100 may include one or more relay stations. A relay station is a network node that can receive transmissions of data from an upstream node (e.g., a network node 110 or a UE 120) and transmit transmissions of data to a downstream node (e.g., a UE 120 or a network node 110). A relay station may be a UE 120 that is capable of relaying transmissions for other UEs 120. Figure 1 In the example shown in , a network node 110d (e.g., a relay network node) may communicate with a network node 110a (e.g., a macro network node) and a UE 120d to facilitate communications 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 base station, a relay network node, a relay node, a relay, etc.

[0032] The wireless network 100 may be a heterogeneous network that includes different types of network nodes 110, such as macro network nodes, pico network nodes, femto network nodes, relay network nodes, etc. These different types of network nodes 110 may have different transmit power levels, different coverage areas, and / or different impacts on interference in the wireless network 100. For example, a macro network node may have a high transmit power level (e.g., 5 watts to 40 watts), while a pico network node, a femto network node, and a relay network node may have a lower transmit power level (e.g., 0.1 watt to 2 watts).

[0033] The network controller 130 may be coupled to or in communication with a set of network nodes 110 and may provide coordination and control for the network nodes 110. The network controller 130 may communicate with the network nodes 110 via a backhaul communication link or a midhaul communication link. The network nodes 110 may also communicate directly with each other or indirectly via a wireless backhaul communication link or a wired backhaul communication link. In some aspects, the network controller 130 may be or may include a CU or a core network device.

[0034] UE 120 can be dispersed throughout the wireless network 100, and each UE 120 can be stationary or mobile. UE 120 can include, for example, an access terminal, a terminal, a mobile station and / or a subscriber unit. UE 120 can be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet computer, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device, a biometric device, a wearable device (e.g., a smart watch, smart clothing, smart glasses, a smart wristband, smart jewelry (e.g., a smart ring or a smart bracelet)), an entertainment device (e.g., a music device, a video device and / or a satellite radio), a vehicle component or sensor, a smart meter / sensor, an industrial manufacturing equipment, a global positioning system device, a UE function of a network node and / or any other suitable device configured to communicate via a wireless or wired medium.

[0035] Some UEs 120 may be considered as machine type communication (MTC) or evolved or enhanced machine type communication (eMTC) UEs. MTC UEs and / or eMTC UEs may include, for example, robots, drones, remote devices, sensors, meters, monitors, and / or location tags that may communicate with a network node, another device (e.g., a remote device), or some other entity. Some UEs 120 may be considered as Internet of Things (IoT) devices and / or may be implemented as NB-IoT (narrowband IoT) devices. Some UEs 120 may be considered as customer premises equipment. UE 120 may be included inside a housing that houses components of UE 120, such as a processor component and / or a memory component. In some examples, the processor component and the memory component may be coupled together. For example, a processor component (e.g., one or more processors) and a memory component (e.g., a memory) may be operably coupled, communicatively coupled, electronically coupled, and / or electrically coupled.

[0036] In general, any number of wireless networks 100 may be deployed in a given geographic area. Each wireless network 100 may support a specific RAT and may operate on one or more frequencies. RAT may be referred to as a radio technology, air interface, etc. Frequency may be referred to as a carrier, frequency channel, etc. In a given geographic area, each frequency may support a single RAT to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

[0037] In some examples, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may communicate directly (e.g., without using network node 110 as an intermediary to communicate with each other) using one or more side link channels. For example, UE 120 may communicate using peer-to-peer (P2P) communication, device-to-device (D2D) communication, vehicle-to-everything (V2X) protocols (e.g., which may include vehicle-to-vehicle (V2V) protocols, vehicle-to-infrastructure (V2I) protocols, or vehicle-to-pedestrian (V2P) protocols), and / or mesh networks. In such examples, UE 120 may perform scheduling operations, resource selection operations, and / or other operations described elsewhere herein as being performed by network node 110.

[0038] The devices of the wireless network 100 may communicate using an electromagnetic spectrum that may be subdivided into various categories, bands, channels, etc., based on frequency or wavelength. For example, the devices of the wireless network 100 may communicate using one or more operating bands. In 5G NR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz-7.125 GHz) and FR2 (24.25 GHz-52.6 GHz). It should be understood that, although a portion of FR1 is greater than 6 GHz, FR1 is often (interchangeably) referred to as the "below 6 GHz" band in various documents and articles. A similar naming problem sometimes occurs with respect to FR2, which is often (interchangeably) referred to as the "millimeter wave" band in documents and articles, although different from the extremely high frequency (EHF) band (30 GHz-300 GHz) identified as the "millimeter wave" band by the International Telecommunication Union (ITU).

[0039] The frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Recent 5G NR research has identified the operating bands for these mid-band frequencies as frequency range designation FR3 (7.125GHz-24.25GHz). The bands falling within FR3 can inherit FR1 characteristics and / or FR2 characteristics, so the features of FR1 and / or FR2 can be effectively extended to mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operations to more than 52.6GHz. For example, three higher operating bands have been identified as frequency range designation FR4a or FR4-1 (52.6GHz-71GHz), FR4 (52.6GHz-114.25GHz) and FR5 (114.25GHz300GHz). Each of these higher frequency bands falls within the EHF band.

[0040] In view of the above examples, unless otherwise specifically stated, it should be understood that if the term "below 6 GHz" or the like is used herein, the term may broadly refer to frequencies that may be lower than 6 GHz, may be within FR1, or may include mid-band frequencies. In addition, unless otherwise specifically stated, it should be understood that if the term "millimeter wave" or the like is used herein, the term may broadly refer to frequencies that may include mid-band frequencies, may be within FR2, FR4, FR4-a or FR4-1, and / or FR5, or may be within the EHF band. It is contemplated that the frequencies included in these operating bands (e.g., FR1, FR2, FR3, FR4, FR4-a, FR4-1, and / or FR5) may be modified, and the techniques described herein are applicable to those modified frequency ranges.

[0041] In some aspects, a first UE (e.g., UE 120a) may include a communication manager 140. As described in more detail elsewhere herein, the communication manager 140 may receive a sidelink transmission associated with a broadcast type from a second UE (e.g., UE 120e); and send a hybrid automatic repeat request (HARQ) feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink. Additionally or alternatively, the communication manager 140 may perform one or more other operations described herein.

[0042] In some aspects, the communication manager 140 may receive sidelink control information (SCI) from the second UE; receive a sidelink transmission from the second UE; and send HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink. Additionally or alternatively, the communication manager 140 may perform one or more other operations described herein.

[0043] As indicated above, Figure 1 are provided as examples. Other examples can be found in the Figure 1 The examples described are different.

[0044] Figure 2 2 is a diagram illustrating an example 200 of a network node 110 communicating with a UE 120 in a wireless network 100 according to the present disclosure. The network node 110 may be equipped with a set of antennas 234a to 234t, such as T antennas (T≥1). The UE 120 may be equipped with a set of antennas 252a to 252r, such as R antennas (R≥1). The network node 110 of example 200 includes one or more radio frequency components, such as an antenna 234 and a modem 254. In some examples, the 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 a radio frequency component that facilitates direct communication with the UE 120, such as one or more CUs or one or more DUs.

[0045] At network node 110, transmit processor 220 may receive data intended for UE 120 (or a set of UEs 120) from data source 212. Transmit processor 220 may select one or more modulation and coding schemes (MCS) for UE 120 based at least in part on one or more channel quality indicators (CQIs) received from UE 120. Network node 110 may process (e.g., code and modulate) the data for UE 120 based at least in part on the MCS selected for UE 120, and may provide data symbols for UE 120. Transmit processor 220 may process system information (e.g., for semi-static resource allocation information (SRPI)) and control information (e.g., CQI requests, grants, and / or upper layer signaling), and provide overhead symbols and control symbols. The transmit processor 220 may generate reference symbols for reference signals (e.g., cell-specific reference signals (CRS) or demodulation reference signals (DMRS)) and synchronization signals (e.g., primary synchronization signals (PSS) or secondary synchronization signals (SSS)). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on ​​data symbols, control symbols, overhead symbols, and / or reference symbols, where applicable, and may provide a set of output symbol streams (e.g., T output symbol streams) to a corresponding set of modems 232 (e.g., T modems) (shown as modems 232a to 232t). For example, each output symbol stream may be provided to a modulator component (shown as MOD) of the modem 232. Each modem 232 may process a corresponding output symbol stream (e.g., for OFDM) using a corresponding modulator component to obtain an output sample stream. Each modem 232 may also process (e.g., convert to analog, amplify, filter, and / or upconvert) the output sample stream using a corresponding modulator component to obtain a downlink signal. The modems 232a through 232t may transmit a set of downlink signals (eg, T downlink signals) via a corresponding set of antennas 234 (eg, T antennas) (shown as antennas 234a through 234t).

[0046] At the UE 120, a set of antennas 252 (shown as antennas 252a to 252r) may receive downlink signals from the network node 110 and / or other network nodes 110 and may provide a set of received signals (e.g., R received signals) to a set of modems 254 (e.g., R modems) (shown as modems 254a to 254r). For example, each received signal may be provided to a demodulator component (shown as DEMOD) of the modem 254. Each modem 254 may use a corresponding demodulator component to condition (e.g., filter, amplify, downconvert, and / or digitize) the received signal to obtain input samples. Each modem 254 may use a demodulator component to further process the input samples (e.g., for OFDM) to obtain received symbols. A MIMO detector 256 may obtain received symbols from the modem 254, may perform MIMO detection on the received symbols where applicable, and may provide detected symbols. The receive processor 258 may process (e.g., demodulate and decode) the detected symbols, may provide decoded data for the UE 120 to the data sink 260, and may provide decoded control information and system information to the controller / processor 280. The term "controller / processor" may refer to one or more controllers, one or more processors, or a combination thereof. The channel processor may determine a reference signal received power (RSRP) parameter, a received signal strength indicator (RSSI) parameter, a reference signal received quality (RSRQ) parameter, and / or a CQI parameter, among other things. In some examples, one or more components of the UE 120 may be included in the housing 284.

[0047] 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.

[0048] One or more antennas (e.g., antennas 234a to 234t and / or antennas 252a to 252r) may include, or may be included within, one or more antenna panels, one or more antenna groups, one or more groups of antenna elements, and / or one or more antenna arrays, etc. An antenna panel, an antenna group, a group of antenna elements, and / or an antenna array may include one or more antenna elements (in a single housing or multiple housings), a group of coplanar antenna elements, a group of non-coplanar antenna elements, and / or may be coupled to one or more transmit and / or receive components (such as, Figure 2 One or more antenna elements of one or more components).

[0049] On the uplink, at the UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information from a controller / processor 280 (e.g., for reports including RSRP, RSSI, RSRQ, and / or CQI). The transmit processor 264 may generate reference symbols for one or more reference signals. The symbols from the transmit processor 264 may be pre-decoded by a TX MIMO processor 266, where applicable, further processed by a modem 254 (e.g., 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 an antenna 252, a modem 254, a MIMO detector 256, a receive processor 258, a transmit processor 264, and / or a TX MIMO processor 266. The transceiver may be used by a processor (eg, controller / processor 280) and memory 282 to perform the functions described herein (eg, with reference to Figures 5 to 15 ) or any aspects of any of the methods described herein.

[0050] At the network node 110, uplink signals from the UE 120 and / or other UEs may be received by the antenna 234, processed by the modem 232 (e.g., a demodulator component (shown as DEMOD) of the modem 232), detected by the MIMO detector 236 (where applicable), and further processed by the receive processor 238 to obtain decoded data and control information transmitted by the UE 120. The receive processor 238 may provide the decoded data to the data sink 239 and 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 communication and / or uplink communication. 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 antenna 234, modem 232, MIMO detector 236, receive processor 238, transmit processor 220, and / or TX MIMO processor 230. The transceiver may be used by a processor (e.g., controller / processor 240) and memory 242 to perform the operations described herein (e.g., with reference to Figures 5 to 15 ) or any aspects of any of the methods described herein.

[0051] The controller / processor 240 of the network node 110, the controller / processor 280 of the UE 120, and / or Figure 2 Any other components of the may perform one or more techniques associated with sending feedback using time slots based at least in part on a set of timelines, 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, and / or Figure 2 Any other component of may perform or direct e.g. Fig.13 The process of 1300 Fig.14 1400 and / or operations of other processes as described herein. Memory 242 and memory 282 may store data and program codes for network node 110 and UE 120, respectively. In some examples, memory 242 and / or memory 282 may include a non-transitory computer-readable medium storing one or more instructions (e.g., code and / or program code) for wireless communication. For example, the one or more instructions, when executed by one or more processors of network node 110 and / or UE 120 (e.g., directly, or after compilation, conversion, and / or interpretation), may cause the one or more processors, UE 120, and / or network node 110 to perform or direct, for example, Fig.13 The process of 1300 Fig.14 The process 1400 and / or operations of other processes as described herein. In some examples, executing instructions may include running instructions, converting instructions, compiling instructions, and / or interpreting instructions, etc.

[0052] In some aspects, a first UE (e.g., UE 120a) includes means for receiving a sidelink transmission associated with a broadcast type from a second UE (e.g., UE 120e); and / or means for sending HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink. In some aspects, the first UE includes means for receiving an SCI from the second UE; means for receiving the sidelink transmission from the second UE; and / or means for sending HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink. Means for the first UE to perform the operations described herein may include, for example, one or more of the 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.

[0053] Although Figure 2 The blocks in the 2000 and 2010 are illustrated as distinct components, but the functionality described above for these blocks may be implemented in a single hardware, software, or combined component or in various combinations of components. For example, the functionality described with respect to the transmit processor 264, the receive processor 258, and / or the TX MIMO processor 266 may be performed by or under the control of the controller / processor 280.

[0054] As indicated above, Figure 2 are provided as examples. Other examples can be found in the Figure 2 The examples described are different.

[0055] The deployment of a communication system (such as a 5G NR system) can be arranged in a variety of ways with various components or components. In a 5G NR system or network, a network node, a network entity, a mobility element of a network, a RAN node, a core network node, a network element, a base station or network equipment can be implemented in an aggregated or decomposed architecture. For example, a base station (such as a node B (NB), an evolved NB (eNB), an NR BS, a 5G NB, an access point (AP), a TRP or a cell, etc.) or one or more units (or one or more components) performing base station functionality can be implemented as an aggregated base station (also referred to as an independent base station or a monolithic base station) or a decomposed base station. "Network entity" or "network node" may refer to a decomposed base station or one or more units of a decomposed base station (such as one or more CUs, one or more DUs, one or more RUs, or a combination thereof).

[0056] An aggregated base station (e.g., an aggregated network node) may be configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node (e.g., within a single device or unit). A decomposed base station (e.g., a decomposed network node) may be configured to utilize a protocol stack that is physically or logically distributed between two or more units (such as one or more CUs, one or more DUs, or one or more RUs). In some examples, a CU may be implemented within a network node, and one or more DUs may be co-located with the CU, or alternatively, may be geographically or virtually distributed across one or more other network nodes. A DU may be implemented to communicate with one or more RUs. Each of a CU, a DU, and a RU may also be implemented as a virtual unit, such as a virtual central unit (VCU), a virtual distributed unit (VDU), or a virtual radio unit (VRU), and the like.

[0057] Base station type operations or network designs may take into account the aggregated nature of base station functionality. For example, a decomposed base station may be utilized in an IAB network, an open radio access network (O-RAN (such as a network configuration initiated by the O-RAN Alliance)), or a virtualized radio access network (vRAN, also known as a cloud radio access network (C-RAN)) to facilitate the scaling of a communication system by separating base station functionality into one or more units that can be deployed separately. A decomposed base station may include functionality implemented across two or more units at various physical locations, as well as functionality implemented virtually for at least one unit, which may enable flexibility in network design. Individual units of a decomposed base station may be configured for wired or wireless communication with at least one other unit of the decomposed base station.

[0058] NR V2X / sidelink designs may target deployment in licensed spectrum, which may involve sharing spectrum in a licensed cellular band, or using dedicated spectrum for an intelligent transport system (ITS). Cellular V2X communications may be deployed in unlicensed spectrum, as licensed / ITS spectrum for NR V2X may not be guaranteed in some areas. However, unlicensed spectrum may be shared by other technologies (e.g., Wi-Fi), and access to unlicensed spectrum may be subject to regulatory requirements. One regulatory requirement may include listen before talk (LBT), in which a device needs to perform sensing (e.g., listening) before transmitting (e.g., speaking). In LBT, a device may measure the amount of energy in a frequency band, and when the energy meets a threshold (e.g., the energy is below a threshold), the device may be able to transmit using the frequency band. LBT may include Category (CAT) 2 LBT (which may be LBT without random backoff) or CAT 4 LBT (which may be LBT with random backoff with a contention window of variable size).

[0059] NR V2X / sidelink HARQ feedback mechanism can be used for licensed / ITS spectrum. The first UE can send sidelink data via a sidelink channel. Depending on whether the sidelink data is successfully decoded by the second UE, the second UE can send HARQ feedback to the second UE. The HARQ feedback can be a HARQ acknowledgment (ACK) or negative acknowledgment (NACK) feedback. HARQ feedback can be sent via the PSFCH using (pre) configured physical sidelink feedback channel (PSFCH) resources, which can be done once every N time slots (N=0, 1, 2, 4). When the HARQ feedback is for ACK / NACK-based multicast communication (e.g., multicast option 2), the PSFCH resources used to send HARQ feedback corresponding to the physical sidelink shared channel (PSSCH) can be based at least in part on the time / frequency position of the HARQ feedback transmission, the transmitter UE identifier (ID), and / or the receiver UE ID. Each HARQ feedback can be sent using one physical resource block (PRB) and two OFDM symbols in the PSFCH resource.

[0060] Multiple PSFCH resources corresponding to PSSCH transmissions can be configured. Multiple resources can be used for groupcast HARQ feedback, so different Rx UEs in the group can send HARQ feedback in different PSFCH resources. Multiple Tx UEs can send sidelink data in the same resource, causing sidelink data collisions, in which case multiple HARQ resource mappings can mitigate HARQ collisions.

[0061] Figure 3 is a diagram illustrating an example 300 of sidelink transmission according to the present disclosure.

[0062] As shown in reference numeral 302, a time slot may include a physical sidelink control channel (PSCCH) resource, a PSSCH resource, and a PSFCH resource. Sidelink data transmission may be performed using PSCCH resources or PSSCH resources. HARQ feedback may be sent using PSFCH resources. As shown in reference numeral 304, PSSCH transmission may correspond to multiple configured PSFCH resources.

[0063] As indicated above, Figure 3 are provided as examples. Other examples can be found in the Figure 3 The examples described are different.

[0064] Multiple time domain PSFCH opportunities via different HARQ timelines may be employed, which may reduce the probability of LBT failure for HARQ feedback transmission for sidelink communications. Multiple HARQ timelines may be defined such that one PSSCH has more than one PSFCH opportunity in the time domain. Additional time domain opportunities may be accommodated by using different PSFCH resource sets for different timelines or alternatively by partitioning the current PSFCH resource set into static / orthogonal subsets (e.g., odd indices may be associated with a first HARQ timeline, and even indices may be associated with a second HARQ timeline).

[0065] Figure 4 is a diagram illustrating an example 400 of multiple time-domain PSFCH opportunities according to the present disclosure.

[0066] like Figure 4 As shown in , multiple HARQ timelines are configured so that the PSSCH can be associated with more than one PSFCH opportunity in the time domain. The PSSCH can be associated with a first PSFCH resource set, which can be associated with a first HARQ timeline in multiple HARQ timelines in the time domain. The PSSCH can be associated with a second PSFCH resource set, which can be associated with a second HARQ timeline in multiple HARQ timelines in the time domain.

[0067] As indicated above, Figure 4 are provided as examples. Other examples can be found in the Figure 4 The examples described are different.

[0068] For each PSFCH reception opportunity, from a certain number of PSFCH reception opportunities, the UE (e.g., Tx UE) can generate HARQ feedback information to report to a higher layer. For unicast PSSCH transmission, the UE can report the same value (e.g., ACK / NACK) received via PSFCH to a higher layer. When no PSFCH is detected, the UE can regard the HARQ feedback information as NACK. For multicast option 2 (e.g., feedback based on ACK / NACK), when multiple expected PSFCH resources (e.g., all expected PSFCH resources) from a group of Rx UEs are received and carry ACK, the UE can report ACK to a higher layer. When at least one received PSFCH resource carries NACK, or if some expected PSFCH resources are not detected, the UE can report NACK to a higher layer. For multicast option 1 (e.g., only NACK feedback), when the UE determines that there is no PSFCH reception for the PSFCH reception opportunity, the UE can report ACK to a higher layer, otherwise the UE can report NACK to a higher layer. For unicast and multicast option 2, the UE may report NACK to higher layers when no PSFCH is detected in the expected PSFCH resources. For multicast option 1, the UE may report ACK to higher layers when no PSFCH is detected in the expected PSFCH resources.

[0069] For unlicensed bands, the Rx UE may need to perform sensing (e.g., listening) before sending a PSFCH transmission (e.g., talking). When the Rx UE fails to decode the PSSCH transmission and needs to send a NACK on the corresponding PSFCH resource, the Rx UE may fail to send a NACK on the corresponding PSFCH resource when the LBT is unsuccessful. Therefore, the Tx UE may fail to detect PSFCH reception on the corresponding PSFCH opportunity. For unicast PSSCH and multicast option 2, the UE may report a NACK in response to the absence of a PSFCH transmission. However, for multicast option 1 (e.g., only NACK feedback), the absence of PSFCH reception can infer an ACK. Therefore, if a NACK fails to be sent due to a failure of LBT for at least one Rx UE, the Tx UE may refresh the HARQ buffer of the associated side link process, and retransmission of the PSSCH transmission may no longer be possible. The absence of PSFCH reception may be due to the failure of the NACK due to the failure of the LBT, rather than the failure of the ACK.

[0070] In various aspects of the techniques and apparatus described herein, a first UE may receive a sidelink transmission associated with a broadcast type from a second UE. The broadcast type may be unicast, multicast option 1, or multicast option 2. The first UE may send HARQ feedback to the second UE based at least in part on the sidelink transmission. The time slot for sending the HARQ feedback may be based at least in part on a HARQ timeline set associated with the broadcast type. In other words, the first UE may determine the time slot for sending the HARQ feedback based at least in part on a HARQ timeline set corresponding to the broadcast type. The HARQ timeline set may be included in a plurality of HARQ timeline sets configured for the sidelink. Thus, a plurality of HARQ timelines may be (pre)configured or designated for the sidelink, wherein each HARQ timeline set may be (pre)configured or designated for a given broadcast type.

[0071] In some aspects, adaptive multiple opportunities for PSFCH based at least in part on the type of broadcast can be employed because LBT failure can be more detrimental for multicast option 1 as opposed to unicast or multicast option 2. Adaptive multiple time domain opportunities for PSFCH based at least in part on the type of broadcast can be employed. Additionally, adaptive multiple frequency domain opportunities for PSFCH can be employed.

[0072] Figure 5 is a diagram illustrating an example 500 associated with sending feedback using time slots based at least in part on a set of timelines according to the present disclosure. Figure 5 As shown in , example 500 includes communications between a first UE (eg, UE 120a) and a second UE (eg, UE 120e). In some aspects, the first UE and the second UE may be included in a wireless network (such as wireless network 100).

[0073] As shown by reference numeral 502, the first UE may receive a sidelink transmission associated with a broadcast type from the second UE. The first UE may receive the sidelink transmission via a sidelink channel between the first UE and the second UE. The broadcast type may be unicast, groupcast with HARQ feedback based only on NACK (e.g., groupcast option 1), or groupcast with HARQ feedback based on ACK / NACK (e.g., groupcast option 2). In other words, the sidelink transmission may be associated with unicast, groupcast with HARQ feedback based only on NACK, or groupcast with HARQ feedback based on ACK / NACK. The sidelink transmission may be associated with an unlicensed band (e.g., the sidelink transmission may be performed using a frequency within an unlicensed band).

[0074] As indicated by reference numeral 504, the first UE may send HARQ feedback to the second UE based at least in part on the sidelink transmission. The time slot for sending the HARQ feedback may be based at least in part on a HARQ timeline set associated with the broadcast type, wherein the HARQ timeline set may be included in a plurality of HARQ timeline sets configured for the sidelink. The first UE may determine the time slot for sending the HARQ feedback based at least in part on the HARQ timeline set corresponding to the broadcast type.

[0075] In some aspects, such as Figure 6 As shown in the example in, multiple HARQ timeline sets can be (pre)configured or specified for the side link, and each set can be (pre)configured or specified for a given broadcast type. For a given broadcast type, the UE can determine the time slot for HARQ feedback transmission based at least in part on the HARQ timeline set corresponding to the given broadcast type. For example, two sets of HARQ timelines can be specified, where the first set of HARQ timelines can include two HARQ timelines (k1, k2), and the second set of HARQ timelines can include four HARQ timelines (k1', k2', k3', k4'). The first set of HARQ timelines can be used for unicast / multicast option 2, and the second set of HARQ timelines can be used for multicast option 1.

[0076] In some aspects, multiple PSFCH resource sets may be configured for HARQ feedback transmission based at least in part on a HARQ timeline in a union of multiple HARQ timeline sets, where each PSFCH resource set may have an associated HARQ timeline. Figure 7 As shown in the example in FIG. 1 , different PSFCH resource sets in multiple PSFCH resource sets can be frequency-division multiplexed. Figure 8 As shown in the example in, different PSFCH resource sets in multiple PSFCH resource sets can be time-division multiplexed in different time slots or symbols. Fig. 9 As shown in the example in, different PSFCH resource sets in multiple PSFCH resource sets can be frequency-division multiplexed and time-division multiplexed.

[0077] In some aspects, multiple HARQ timeline sets may be enabled based at least in part on HARQ feedback resource mapping. Multiple PSFCH resource sets may be (pre)configured based at least in part on HARQ timelines in the union of multiple HARQ timeline sets. For example, two sets of HARQ timelines may be specified, wherein a first set of HARQ timelines may include two HARQ timelines (k1, k2), and a second set of HARQ timelines may include four timelines (k1', k2', k3', k4'), wherein k1'=k1, k2'=k2, then the union of the first set and the second set may be (k1', k2', k3', k4'). In this case, four PSFCH resource sets may be (pre)configured for HARQ feedback transmission, and each resource set may have an associated HARQ timeline.

[0078] In some aspects, a single PSFCH resource set may be configured for multiple HARQ timeline sets. A PSFCH resource subset of a single PSFCH resource set may be determined based at least in part on a time domain location and a frequency domain location of a sidelink transmission. The HARQ feedback resource of the PSFCH resource subset may be based at least in part on a first UE identifier, a second UE identifier, and a HARQ timeline index for sending HARQ feedback. The HARQ timeline indexes for the HARQ timeline sets in the multiple HARQ timeline sets may be sorted in increasing or decreasing order.

[0079] In some aspects, a single PSFCH resource set may be (pre)configured for multiple HARQ timeline sets, but the HARQ feedback resources may be determined based at least in part on the HARQ timeline index. The HARQ timeline index may be sorted in increasing / decreasing order of the HARQ timeline sets. For example, two sets of HARQ timelines may be specified, wherein a first set of HARQ timelines may include two HARQ timelines (k1, k2), and a second set of HARQ timelines may include four timelines (k1', k2', k3', k4'). Thus, the HARQ timeline index may be m=0, 1, 2, 3, 4, 5, which may correspond to (k1, k2, k1', k2', k3', k4'), respectively.

[0080] In some aspects, the UE may initially determine a subset of HARQ feedback resources in a HARQ feedback resource set. The HARQ feedback resource subset may be based at least in part on the PSSCH time and frequency location. The UE may then determine the HARQ feedback resource based on the HARQ feedback resource subset, which may be based at least in part on the Tx UEID (P ID ), Rx UE member ID (MID ) and a HARQ timeline index (m, m=0, 1, ..., M-1) for HARQ feedback transmission, where M is a defined integer. For example, (mod: modulo operator).

[0081] In some aspects, multiple PSFCH resource sets may be configured based at least in part on multiple HARQ timeline sets. A PSFCH resource set in a plurality of PSFCH resource sets may be associated with a HARQ timeline set. For each HARQ timeline set in a plurality of HARQ timeline sets, a PSFCH resource subset in an associated PSFCH resource set may be determined based at least in part on a time domain location and a frequency domain location of a sidelink transmission. A HARQ feedback resource for a PSFCH resource subset may be based at least in part on a HARQ timeline index in the HARQ timeline set, a first UE identifier, and a second UE identifier.

[0082] In some aspects, multiple PSFCH resource sets may be (pre-)configured based at least in part on multiple HARQ timeline sets, where each PSFCH resource set may be associated with a HARQ timeline set, such as Fig.10 As shown in the example in . Within each HARQ timeline set, the HARQ feedback resource can be determined based at least in part on the index of the HARQ timeline in the set. Different PSFCH resource sets can be frequency-division multiplexed and / or time-division multiplexed. For example, two sets of HARQ timelines can be specified, where the first set of HARQ timelines can include two HARQ timelines (k1, k2), and the second set of HARQ timelines can include four timelines (k1', k2', k3', k4'). In this case, two PSFCH resource sets can be (pre-)configured for HARQ feedback transmission, and each PSFCH resource set can be associated with a HARQ timeline set.

[0083] In some aspects, for a first set of HARQ timelines, M1 HARQ timelines may be specified or configured, and for a second set of HARQ timelines, M2 HARQ timelines may be specified or configured. The UE may first determine a subset of HARQ feedback resources in each PSFCH resource set, which may be based at least in part on the PSSCH time and frequency location. For example, the first subset of HARQ feedback resources may include the first subset of HARQ feedback resources in the first PSFCH resource set. HARQ feedback resources, and the second subset of HARQ feedback resources may include the second PSFCH resource set The UE may then determine a HARQ feedback resource based on each subset of HARQ feedback resources, the HARQ feedback resource being based at least in part on the Tx UE ID (P ID ), Rx UE member ID (M ID ) and a HARQ timeline index for HARQ feedback transmission in a corresponding HARQ timeline set. The first HARQ feedback resource is determined, where m=0, 1, ..., M1-1. to determine the second HARQ feedback resource, where m=0, 1, ..., M2-1.

[0084] As indicated above, Figure 5 are provided as examples. Other examples can be found in the Figure 5 The examples described are different.

[0085] Figure 6 is a diagram illustrating an example 600 associated with sending feedback using time slots based at least in part on a set of timelines in accordance with the present disclosure.

[0086] like Figure 6 As shown in , two sets of HARQ timelines may be specified. The first set of HARQ timelines may include two HARQ timelines (k1, k2). The two HARQ timelines may be associated with two PSFCH opportunities. The first set of HARQ timelines may be used for unicast or multicast option 2. The second set of HARQ timelines may include four HARQ timelines (k1', k2', k3', k4'). The second set of HARQ timelines may be used for multicast option 1. The four HARQ timelines may be associated with four PSFCH opportunities, which may partially overlap with the two PSFCH opportunities associated with the first set of HARQ timelines.

[0087] As indicated above, Figure 6 are provided as examples. Other examples can be found in the Figure 6 The examples described are different.

[0088] Figure 7 is a diagram illustrating an example 700 associated with sending feedback using time slots based at least in part on a set of timelines in accordance with the present disclosure.

[0089] like Figure 7As shown in , different PSFCH resource sets can be frequency-division multiplexed. Different PSFCH resource sets may include a first PSFCH resource set, a second PSFCH resource set, a third PSFCH resource set, and a fourth PSFCH resource set. Each of the first PSFCH resource set, the second PSFCH resource set, the third PSFCH resource set, and the fourth PSFCH resource set may be associated with a HARQ timeline. For example, the first PSFCH resource set may be associated with a first HARQ timeline (k1'), the second PSFCH resource set may be associated with a second HARQ timeline (k2'), the third PSFCH resource set may be associated with a third HARQ timeline (k3'), and the fourth PSFCH resource set may be associated with a fourth HARQ timeline (k4').

[0090] As indicated above, Figure 7 are provided as examples. Other examples can be found in the Figure 7 The examples described are different.

[0091] Figure 8 is a diagram illustrating an example 800 associated with sending feedback using time slots based at least in part on a set of timelines in accordance with the present disclosure.

[0092] like Figure 8 As shown in , different PSFCH resource sets may be time-division multiplexed on different time slots / symbols. Different PSFCH resource sets may include a first PSFCH resource set, a second PSFCH resource set, a third PSFCH resource set, and a fourth PSFCH resource set, and each PSFCH resource set may have an associated HARQ timeline.

[0093] As indicated above, Figure 8 are provided as examples. Other examples can be found in the Figure 8 The examples described are different.

[0094] Fig. 9 is a diagram illustrating an example 900 associated with sending feedback using time slots based at least in part on a set of timelines in accordance with the present disclosure.

[0095] like Fig. 9 As shown in , different PSFCH resource sets may be frequency-division multiplexed and time-division multiplexed. Different PSFCH resource sets may include a first PSFCH resource set, a second PSFCH resource set, a third PSFCH resource set, and a fourth PSFCH resource set, and each PSFCH resource set may have an associated HARQ timeline.

[0096] As indicated above, Fig. 9 are provided as examples. Other examples can be found in the Fig. 9 The examples described are different.

[0097] Fig.10 is a diagram illustrating an example 1000 associated with sending feedback using time slots based at least in part on a set of timelines in accordance with the present disclosure.

[0098] like Fig.10 As shown in , different PSFCH resource sets can be frequency-division multiplexed, where each PSFCH resource set can be associated with a set of HARQ timelines. For example, a first PSFCH resource set can be associated with a first set of HARQ timelines, and a second PSFCH resource set can be associated with a second set of HARQ timelines. The first set of HARQ timelines can include four timelines (k1', k2', k3', k4'), and the second set of HARQ timelines can include two timelines (k1, k2).

[0099] As indicated above, Fig.10 are provided as examples. Other examples can be found in the Fig.10 The examples described are different.

[0100] Fig.11 1 is a diagram illustrating an example 1100 associated with sending feedback using time slots based at least in part on a set of timelines according to the present disclosure. Fig.11 As shown in , example 1100 includes communication between a first UE (eg, UE 120a) and a second UE (eg, UE 120e). In some aspects, the first UE and the second UE may be included in a wireless network (such as wireless network 100).

[0101] As shown by reference numeral 1102, the first UE may receive SCI from the second UE. The SCI may carry information associated with the sidelink transmission. The SCI may indicate a HARQ timeline subset, wherein the HARQ timeline subset may be included in a plurality of HARQ timelines configured for the sidelink.

[0102] As shown by reference numeral 1104, the first UE may receive a sidelink transmission from the second UE. The first UE may receive the sidelink transmission based at least in part on the SCI. The first UE may receive the sidelink transmission via a sidelink channel between the first UE and the second UE. The sidelink transmission may be associated with an unlicensed band.

[0103] As indicated by reference numeral 1106, the first UE may send HARQ feedback to the second UE based at least in part on the sidelink transmission. The time slot for sending the HARQ feedback may be based at least in part on a HARQ timeline subset indicated by the SCI, wherein the HARQ timeline subset may be included in a plurality of HARQ timelines configured for the sidelink. The SCI may indicate a number of HARQ timelines associated with the HARQ timeline subset, wherein the number of HARQ timelines among the plurality of HARQ timelines may be used to send the HARQ feedback. The SCI may indicate a plurality of HARQ timeline code points, and a HARQ timeline code point among the plurality of HARQ timeline code points may indicate a HARQ timeline subset.

[0104] In some aspects, multiple HARQ timelines may be (pre)configured or designated for the sidelink, and a subset of HARQ timelines may be indicated by the SCI. In a first approach, the number of HARQ timelines may be indicated by the SCI, and a first plurality of HARQ timelines may be used. For example, four HARQ timelines (k1, k2, k3, k4) may be configured, and the number of HARQ timelines indicated by the SCI may be N, in which case the first N HARQ timelines of the four HARQ timelines may be used for HARQ feedback. In a second approach, multiple HARQ timeline code points may be indicated by the SCI, and each HARQ timeline code point may indicate one or more HARQ timelines. For example, four HARQ timelines may be configured, in which case up to N HARQ timelines may be indicated. code points, each of which can indicate one or more HARQ timelines.

[0105] In some aspects, in the first method, the number of HARQ timelines may be indicated by the SCI. For index "0", the number of HARQ timelines may be one, which may correspond to the first HARQ timeline (k1). For index "1", the number of HARQ timelines may be two, which may correspond to the first HARQ timeline and the second HARQ timeline (k1, k2). For index "2", the number of HARQ timelines may be three, which may correspond to the first HARQ timeline, the second HARQ timeline, and the third HARQ timeline (k1, k2, k3). For index "3", the number of HARQ timelines may be four, which may correspond to the first HARQ timeline, the second HARQ timeline, the third HARQ timeline, and the fourth HARQ timeline (k1, k2, k3, k4).

[0106] In some aspects, in the second method, multiple HARQ timeline code points may be indicated by the SCI. Code point "0000" may correspond to HARQ timeline (k1), code point "0001" may correspond to HARQ timeline (k2), code point "0010" may correspond to HARQ timeline (k3), code point "0011" may correspond to HARQ timeline (k4), code point "0100" may correspond to HARQ timeline (k1, k2), code point "0101" may correspond to HARQ timeline (k1, k3), code point "0110" may correspond to HARQ timeline (k1, k4), code point "0111" may correspond to HARQ timeline (k2, k3 ...4), code point "0110" may correspond to HARQ timeline (k2, k3), code point "0111" may correspond to HARQ timeline (k2, k3), code point "0100" may correspond to HARQ timeline (k1, k2), code point "0101" may correspond to HARQ timeline (k1, k3), code point "0110" may correspond to HARQ timeline (k1, k4), code point "0111" may correspond to HARQ timeline (k2, k3), code point "0100" may correspond to HARQ timeline (k1, k3), code point "0110" may correspond to HARQ timeline (k2, k3), code point "0111" may correspond to HARQ time Corresponding to the HARQ timeline (k2, k4), the code point "1001" may correspond to the HARQ timeline (k3, k4), the code point "1010" may correspond to the HARQ timeline (k1, k2, k3), the code point "1011" may correspond to the HARQ timeline (k1, k2, k4), the code point "1100" may correspond to the HARQ timeline (k1, k3, k4), the code point "1101" may correspond to the HARQ timeline (k2, k3, k4), the code point "1100" may correspond to the HARQ timeline (k1, k2, k3, k4), and the code point "1111" may be reserved.

[0107] As indicated above, Fig.11 are provided as examples. Other examples can be found in the Fig.11 The examples described are different.

[0108] Fig.12 is a diagram illustrating an example 1200 associated with sending feedback using time slots based at least in part on a set of timelines in accordance with the present disclosure.

[0109] like Fig.12 As shown in , the first SCI may indicate two HARQ timelines (k1, k2). The two HARQ timelines may correspond to two time domain opportunities. The second SCI may indicate four HARQ timelines (k1, k2, k3, k4). The four HARQ timelines may correspond to four time domain opportunities. The two HARQ timelines and the four HARQ timelines may be indicated via the SCI according to a plurality of HARQ timelines that are (pre) configured or designated for the side link.

[0110] As indicated above, Fig.12 are provided as examples. Other examples can be found in the Fig.12 The examples described are different.

[0111] Fig.13is a diagram illustrating an example process 1300 performed, for example, by a first UE in accordance with the present disclosure. The example process 1300 is an example in which a first UE (eg, UE 120a) performs operations associated with sending feedback using time slots based at least in part on a set of timelines.

[0112] like Fig.13 As shown in FIG. 1 , in some aspects, process 1300 may include receiving a sidelink transmission associated with a broadcast type from a second UE (block 1310). For example, a first UE (e.g., using Fig.15 The communication manager 140 and / or receiving component 1502 depicted in FIG. 1 may receive a sidelink transmission associated with a broadcast type from a second UE, as described above.

[0113] like Fig.13 As further shown in FIG. 1 , in some aspects, process 1300 may include sending HARQ feedback to a second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink (block 1320). For example, a first UE (e.g., using Fig.15 The communication manager 140 and / or the sending component 1504 depicted in the figure can send HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein the time slot for sending the HARQ feedback is based at least in part on the HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in the multiple HARQ timeline sets configured for the sidelink, as described above.

[0114] Process 1300 may include additional aspects, such as any single aspect or any combination of aspects described below and / or in conjunction with one or more other processes described elsewhere herein.

[0115] In a first aspect, process 1300 includes determining a time slot for sending HARQ feedback based at least in part on a set of HARQ timelines corresponding to a broadcast type.

[0116] In a second aspect, alone or in combination with the first aspect, the broadcast type is one of unicast, groupcast with NACK-only based HARQ feedback, or groupcast with ACK / NACK based HARQ feedback.

[0117] In a third aspect, either alone or in combination with one or more of the first and second aspects, multiple PSFCH resource sets are configured for HARQ feedback transmission based at least in part on a HARQ timeline in a union of multiple HARQ timeline sets, and each PSFCH resource set has an associated HARQ timeline.

[0118] In a fourth aspect, alone or in combination with one or more of the first to third aspects, different PSFCH resource sets among the plurality of PSFCH resource sets are frequency division multiplexed.

[0119] In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, different PSFCH resource sets among the plurality of PSFCH resource sets are time division multiplexed in different time slots or symbols.

[0120] In a sixth aspect, alone or in combination with one or more of the first to fifth aspects, different PSFCH resource sets among the plurality of PSFCH resource sets are frequency division multiplexed and time division multiplexed.

[0121] In the seventh aspect, alone or in combination with one or more of the first to sixth aspects, a single PSFCH resource set is configured for multiple HARQ timeline sets; a PSFCH resource subset of the single PSFCH resource set is determined at least in part based on the time domain position and frequency domain position of the side link transmission, and the HARQ feedback resource of the PSFCH resource subset is at least in part based on the first UE identifier, the second UE identifier, and the HARQ timeline index for sending HARQ feedback; and the HARQ timeline indexes of the HARQ timeline sets in the multiple HARQ timeline sets are sorted in ascending or descending order.

[0122] In an eighth aspect, either alone or in combination with one or more of the first to seventh aspects, multiple PSFCH resource sets are configured at least in part based on multiple HARQ timeline sets, and the PSFCH resource sets in the multiple PSFCH resource sets are associated with the HARQ timeline sets.

[0123] In the ninth aspect, alone or in combination with one or more of the first to eighth aspects, for each HARQ timeline set in a plurality of HARQ timeline sets, a PSFCH resource subset in an associated PSFCH resource set is determined at least in part based on a time domain position and a frequency domain position of a side link transmission, and the HARQ feedback resources of the PSFCH resource subset are at least in part based on a HARQ timeline index, a first UE identifier, and a second UE identifier in the HARQ timeline set.

[0124] In a tenth aspect, alone or in combination with one or more of the first to ninth aspects, the sidelink transmission is associated with an unlicensed band.

[0125] although Fig.13 An example block diagram of process 1300 is shown, but in some aspects, process 1300 may include Fig.13 The blocks depicted in the process 1300 may include additional blocks, fewer blocks, different blocks, or blocks arranged in a different manner than those depicted in the process 1300. Additionally or alternatively, two or more blocks in the blocks of the process 1300 may be performed in parallel.

[0126] Fig.14 is a diagram illustrating an example process 1400 performed, for example, by a first UE in accordance with the present disclosure. Example process 1400 is an example in which a first UE (eg, UE 120) performs operations associated with sending feedback using time slots based at least in part on a set of timelines.

[0127] like Fig.14 As shown in FIG. 14 , in some aspects, process 1400 may include receiving an SCI from a second UE (block 1410). For example, a first UE (e.g., using Fig.15 The communication manager 140 and / or receiving component 1502 depicted in FIG. 1 may receive the SCI from the second UE, as described above.

[0128] like Fig.14 As further shown in FIG. 14 , in some aspects, process 1400 may include receiving a sidelink transmission from a second UE (block 1420). For example, a first UE (e.g., using Fig.15 The communication manager 140 and / or receiving component 1502 depicted in the figure can receive the side link transmission from the second UE, as described above.

[0129] like Fig.14 As further shown in FIG. 14 , in some aspects, process 1400 may include sending HARQ feedback to a second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink (block 1430). For example, a first UE (e.g., using Fig.15 The communication manager 140 and / or the sending component 1504 depicted in the figure can send HARQ feedback to the second UE based at least in part on the side link transmission, wherein the time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in the multiple HARQ timelines configured for the side link, as described above.

[0130] Process 1400 may include additional aspects, such as any single aspect or any combination of aspects described below and / or in conjunction with one or more other processes described elsewhere herein.

[0131] In a first aspect, the SCI indicates a number of HARQ timelines associated with the HARQ timeline subset, and the number of HARQ timelines among a plurality of HARQ timelines is used to send HARQ feedback.

[0132] In a second aspect, alone or in combination with the first aspect, the SCI indicates a plurality of HARQ timeline codepoints, and a HARQ timeline codepoint of the plurality of HARQ timeline codepoints indicates a HARQ timeline subset.

[0133] In a third aspect, alone or in combination with one or more of the first and second aspects, the sidelink transmission is associated with an unlicensed band.

[0134] although Fig.14 An example block diagram of process 1400 is shown, but in some aspects, process 1400 may include Fig.14 The blocks depicted in the process 1400 may include additional blocks, fewer blocks, different blocks, or blocks arranged in a different manner than those depicted in the process 1400. Additionally or alternatively, two or more blocks in the blocks of the process 1400 may be performed in parallel.

[0135] Fig.15 1 is a diagram of an example apparatus 1500 for wireless communication. Apparatus 1500 may be a first UE, or the first UE may include apparatus 1500. In some aspects, apparatus 1500 includes a receiving component 1502 and a transmitting component 1504 that may communicate with each other (e.g., via one or more buses and / or one or more other components). As shown, apparatus 1500 may communicate with another apparatus 1506 (such as a UE, a base station, or another wireless communication device) using receiving component 1502 and transmitting component 1504. As further shown, apparatus 1500 may include a communication manager 140. Communication manager 140 may include, among other things, a determining component 1508.

[0136] In some aspects, the apparatus 1500 may be configured to perform the Figures 5 to 12 Additionally or alternatively, the apparatus 1500 may be configured to perform one or more processes described herein, such as Fig.13 The process of 1300 Fig.14 In some aspects, the apparatus 1500 and / or Fig.15 One or more of the components shown in the figure may include a combination of Figure 2 Additionally or alternatively, Fig.15 One or more of the components shown in the figure may be combined with Figure 2 Additionally or alternatively, one or more components in a set of components may be implemented at least in part as software stored in a memory. For example, a component (or a portion of a component) may be implemented as instructions or codes stored in a non-transitory computer-readable medium and executable by a controller or processor to perform the function or operation of the component.

[0137] The receiving component 1502 may receive communications, such as reference signals, control information, data communications, or combinations thereof, from the apparatus 1506. The receiving component 1502 may provide the received communications to one or more other components of the apparatus 1500. In some aspects, the receiving component 1502 may perform signal processing (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, demapping, equalization, interference cancellation, or decoding) on ​​the received communications and may provide the processed signals to one or more other components of the apparatus 1500. In some aspects, the receiving component 1502 may include combining Figure 2 One or more antennas, modems, demodulators, MIMO detectors, receive processors, controllers / processors, memories, or combinations thereof of the described first UE.

[0138] Transmit component 1504 may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to device 1506. In some aspects, one or more other components of device 1500 may generate communications and may provide the generated communications to transmit component 1504 for transmission to device 1506. In some aspects, transmit component 1504 may perform signal processing (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, etc.) on the generated communications and may transmit the processed signals to device 1506. In some aspects, transmit component 1504 may include combining Figure 2 One or more antennas, modems, modulators, transmit MIMO processors, transmit processors, controllers / processors, memories, or combinations thereof of the described first UE. In some aspects, the transmit component 1504 can be co-located with the receive component 1502 in a transceiver.

[0139] The receiving component 1502 may receive a sidelink transmission associated with the broadcast type from the second UE. The sending component 1504 may send HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on the HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink. The determining component 1508 may determine a time slot for sending the HARQ feedback based at least in part on the HARQ timeline set corresponding to the broadcast type.

[0140] The receiving component 1502 may receive the SCI from the second UE. The receiving component 1502 may receive the sidelink transmission from the second UE. The transmitting component 1504 may send HARQ feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink.

[0141] Fig.15 The number and arrangement of components shown in the figure are provided as examples. In practice, there may be Fig.15 The components shown in the figure may include additional components, fewer components, different components, or components arranged in a different manner. Fig.15 Two or more components shown in the figure may be implemented in a single component, or Fig.15 The single component shown in can be implemented as multiple distributed components. Additionally or alternatively, Fig.15 A set (one or more) of components shown in the figure may perform the operations described as being performed by Fig.15 One or more functions performed by another group of components shown in the figure.

[0142] The following provides an overview of some aspects of the disclosure:

[0143] Aspect 1: A method of wireless communication performed by a first user equipment (UE), comprising: receiving a sidelink transmission associated with a broadcast type from a second UE; and sending a hybrid automatic repeat request (HARQ) feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink.

[0144] Aspect 2: The method according to aspect 1, further comprising: determining the time slot for sending the HARQ feedback based at least in part on the HARQ timeline set corresponding to the broadcast type.

[0145] Aspect 3: The method according to any one of aspects 1 to 2, wherein the broadcast type is one of: unicast, groupcast with HARQ feedback based only on negative acknowledgement (NACK), or groupcast with HARQ feedback based on acknowledgement or NACK.

[0146] Aspect 4: A method according to any one of Aspects 1 to 3, wherein multiple physical sidelink feedback channel (PSFCH) resource sets are configured for HARQ feedback transmission based at least in part on a HARQ timeline in a union of the multiple HARQ timeline sets, and wherein each PSFCH resource set has an associated HARQ timeline.

[0147] Aspect 5: The method according to aspect 4, wherein different PSFCH resource sets among the multiple PSFCH resource sets are frequency division multiplexed.

[0148] Aspect 6: The method according to aspect 4, wherein different PSFCH resource sets among the multiple PSFCH resource sets are time-division multiplexed in different time slots or symbols.

[0149] Aspect 7: The method according to aspect 4, wherein different PSFCH resource sets among the multiple PSFCH resource sets are frequency division multiplexed and time division multiplexed.

[0150] Aspect 8: A method according to any one of Aspects 1 to 7, wherein a single physical sidelink feedback channel (PSFCH) resource set is configured for the multiple HARQ timeline sets; a PSFCH resource subset of the single PSFCH resource set is determined at least in part based on the time domain position and frequency domain position of the sidelink transmission, and the HARQ feedback resources of the PSFCH resource subset are at least in part based on a first UE identifier, a second UE identifier, and a HARQ timeline index for sending the HARQ feedback; and the HARQ timeline indexes of the HARQ timeline sets in the multiple HARQ timeline sets are sorted in increasing or decreasing order.

[0151] Aspect 9: A method according to any one of Aspects 1 to 8, wherein multiple physical sidelink feedback channel (PSFCH) resource sets are configured at least in part based on the multiple HARQ timeline sets, and the PSFCH resource sets in the multiple PSFCH resource sets are associated with the HARQ timeline sets.

[0152] Aspect 10: A method according to Aspect 9, wherein for each HARQ timeline set in the multiple HARQ timeline sets, a PSFCH resource subset in the associated PSFCH resource set is determined at least in part based on the time domain position and frequency domain position of the side link transmission, and the HARQ feedback resource of the PSFCH resource subset is at least in part based on the HARQ timeline index, the first UE identifier and the second UE identifier in the HARQ timeline set.

[0153] Aspect 11: The method according to any one of aspects 1 to 10, wherein the sidelink transmission is associated with an unlicensed band.

[0154] Aspect 12: A method of wireless communication performed by a first user equipment (UE), comprising: receiving sidelink control information (SCI) from a second UE; receiving a sidelink transmission from the second UE; and sending a hybrid automatic repeat request (HARQ) feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink.

[0155] Aspect 13: The method according to aspect 12, wherein the SCI indicates the number of HARQ timelines associated with the HARQ timeline subset, and wherein the number of HARQ timelines among the plurality of HARQ timelines are used to send the HARQ feedback.

[0156] Aspect 14: The method according to any one of Aspects 12 to 13, wherein the SCI indicates a plurality of HARQ timeline code points, and a HARQ timeline code point in the plurality of HARQ timeline code points indicates the HARQ timeline subset.

[0157] Aspect 15: The method according to any one of aspects 12 to 14, wherein the sidelink transmission is associated with an unlicensed band.

[0158] Aspect 16: An apparatus for wireless communication at a device, comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform one or more of the methods described in Aspects 1 to 15.

[0159] Aspect 17: A device for wireless communication, comprising: a memory; and one or more processors coupled to the memory, the one or more processors configured to execute the method according to one or more of aspects 1 to 15.

[0160] Aspect 18: An apparatus for wireless communication, comprising: at least one component for performing the method according to one or more of aspects 1 to 15.

[0161] Aspect 19: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method according to one or more of aspects 1 to 15.

[0162] Aspect 20: A non-transitory computer-readable medium storing an instruction set for wireless communication, the instruction set comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform one or more of the methods described in aspects 1 to 15.

[0163] 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 these aspects.

[0164] As used herein, the term "component" is intended to be broadly interpreted as a combination of hardware and / or hardware and software. Whether referred to as software, firmware, middleware, microcode, hardware description language or other names, "software" should be broadly interpreted as meaning instructions, instruction sets, codes, code segments, program codes, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures and / or functions, etc. As used herein, a "processor" is implemented in a combination of hardware and / or hardware and software. It will be apparent that the systems and / or methods described herein can be implemented by a combination of hardware and / or hardware and software in different forms. The actual dedicated control hardware or software code used to implement these systems and / or methods does not limit various aspects. Therefore, there is no reference to a specific software code herein to describe the operation and behavior of the system and / or method, because those skilled in the art will understand that software and hardware can be designed to implement the system and / or method based at least in part on the description herein.

[0165] As used herein, "satisfying a threshold" may refer to a value being greater than a threshold, greater than or equal to a threshold, less than a threshold, less than or equal to a threshold, equal to a threshold, not equal to a threshold, etc., depending on the context.

[0166] Although the specific combination of features is described in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. Many of these features can be combined in a manner that is not specifically described in the claims and / or is not disclosed in the specification. The disclosure of various aspects includes each dependent claim combined with each other claim in the claim set. As used herein, the phrase "at least one of" the list of items refers to any combination of these items (it includes a single member). 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, and any combination with multiple identical elements (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).

[0167] Any element, action or instruction used herein should not be interpreted as critical or necessary unless explicitly stated. In addition, as used herein, the article "one" is intended to include one or more items, and can be used interchangeably with "one or more". In addition, as used herein, the article "said" is intended to include one or more items connected to the article "said", and can be used interchangeably with "one or more". In addition, as used herein, the terms "group" and "group" are intended to include one or more items, and can be used interchangeably with "one or more". If only one item is intended to be referred to, the phrase "only one" or similar terms will be used. In addition, as used herein, the terms "have", "have", "have" etc. are intended to be open terms, which do not limit the elements they modify (for example, "having" A elements can also have B). In addition, the phrase "based on" is intended to represent "based at least in part", unless explicitly stated otherwise. Furthermore, as used herein, the term "or" when used in a series is intended to be open-ended and used interchangeably with "and / or" unless explicitly stated otherwise (e.g., if used in conjunction with "either" or "only one of").

Claims

1. An apparatus for wireless communication at a first user equipment (UE), the apparatus comprising: Memory; and one or more processors coupled to the memory, the one or more processors configured to: receiving a sidelink transmission associated with the broadcast type from a second UE; and and sending hybrid automatic repeat request (HARQ) feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink.

2. The apparatus of claim 1 , wherein the one or more processors are further configured to: The time slot for sending the HARQ feedback is determined based at least in part on the set of HARQ timelines corresponding to the broadcast type.

3. The apparatus of claim 1, wherein the broadcast type is one of: unicast, groupcast with HARQ feedback based only on negative acknowledgement (NACK), or groupcast with HARQ feedback based on either acknowledgement or NACK.

4. An apparatus according to claim 1, wherein multiple physical sidelink feedback channel (PSFCH) resource sets are configured for HARQ feedback transmission based at least in part on the HARQ timelines in the union of the multiple HARQ timeline sets, and wherein each PSFCH resource set has an associated HARQ timeline.

5. The apparatus of claim 4, wherein different PSFCH resource sets among the plurality of PSFCH resource sets are frequency division multiplexed. 6 . The apparatus according to claim 4 , wherein different PSFCH resource sets among the multiple PSFCH resource sets are time-division multiplexed in different time slots or symbols.

7. The apparatus of claim 4, wherein different PSFCH resource sets among the plurality of PSFCH resource sets are frequency division multiplexed and time division multiplexed.

8. The device according to claim 1, wherein: a single physical sidelink feedback channel (PSFCH) resource set configured for the multiple HARQ timeline sets; A PSFCH resource subset of the single PSFCH resource set is determined based at least in part on a time domain location and a frequency domain location of the sidelink transmission, and a HARQ feedback resource of the PSFCH resource subset is based at least in part on a first UE identifier, a second UE identifier, and a HARQ timeline index for sending the HARQ feedback; and The HARQ timeline indexes for the HARQ timeline sets in the plurality of HARQ timeline sets are sorted in increasing or decreasing order.

9. An apparatus according to claim 1, wherein multiple physical sidelink feedback channel (PSFCH) resource sets are configured at least in part based on the multiple HARQ timeline sets, and the PSFCH resource sets in the multiple PSFCH resource sets are associated with the HARQ timeline sets.

10. An apparatus according to claim 9, wherein for each HARQ timeline set in the multiple HARQ timeline sets, a PSFCH resource subset in the associated PSFCH resource set is determined at least in part based on the time domain position and frequency domain position of the side link transmission, and the HARQ feedback resources of the PSFCH resource subset are at least in part based on the HARQ timeline index, the first UE identifier and the second UE identifier in the HARQ timeline set.

11. The apparatus of claim 1, wherein the sidelink transmission is associated with an unlicensed frequency band.

12. An apparatus for wireless communication at a first user equipment (UE), comprising: Memory; and one or more processors coupled to the memory, the one or more processors configured to: receiving sidelink control information (SCI) from a second UE; receiving a sidelink transmission from the second UE; and and sending a hybrid automatic repeat request (HARQ) feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink.

13. The apparatus of claim 12, wherein the SCI indicates a number of HARQ timelines associated with the HARQ timeline subset, and wherein the number of HARQ timelines among the plurality of HARQ timelines are used to send the HARQ feedback.

14. The apparatus of claim 12, wherein the SCI indicates a plurality of HARQ timeline code points, and a HARQ timeline code point of the plurality of HARQ timeline code points indicates the HARQ timeline subset.

15. The apparatus of claim 12, wherein the sidelink transmission is associated with an unlicensed frequency band.

16. A method of wireless communication performed by a first user equipment (UE), the method comprising: receiving a sidelink transmission associated with the broadcast type from a second UE; as well as and sending hybrid automatic repeat request (HARQ) feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline set associated with the broadcast type, and wherein the HARQ timeline set is included in a plurality of HARQ timeline sets configured for the sidelink.

17. The method according to claim 16, further comprising: The time slot for sending the HARQ feedback is determined based at least in part on the set of HARQ timelines corresponding to the broadcast type.

18. The method of claim 16, wherein the broadcast type is one of: unicast, groupcast with HARQ feedback based only on negative acknowledgement (NACK), or groupcast with HARQ feedback based on either acknowledgement or NACK.

19. A method according to claim 16, wherein multiple physical sidelink feedback channel (PSFCH) resource sets are configured for HARQ feedback transmission based at least in part on the HARQ timelines in the union of the multiple HARQ timeline sets, and wherein each PSFCH resource set has an associated HARQ timeline.

20. The method of claim 19, wherein different PSFCH resource sets among the plurality of PSFCH resource sets are frequency division multiplexed.

21. The method according to claim 19, wherein different PSFCH resource sets among the multiple PSFCH resource sets are time-division multiplexed in different time slots or symbols.

22. The method of claim 19, wherein different PSFCH resource sets among the plurality of PSFCH resource sets are frequency division multiplexed and time division multiplexed.

23. The method of claim 16, wherein: a single physical sidelink feedback channel (PSFCH) resource set configured for the multiple HARQ timeline sets; A PSFCH resource subset of the single PSFCH resource set is determined based at least in part on a time domain location and a frequency domain location of the sidelink transmission, and a HARQ feedback resource of the PSFCH resource subset is based at least in part on a first UE identifier, a second UE identifier, and a HARQ timeline index for sending the HARQ feedback; and The HARQ timeline indexes for the HARQ timeline sets in the plurality of HARQ timeline sets are sorted in increasing or decreasing order.

24. The method of claim 16, wherein a plurality of physical sidelink feedback channel (PSFCH) resource sets are configured at least in part based on the plurality of HARQ timeline sets, and a PSFCH resource set in the plurality of PSFCH resource sets is associated with the HARQ timeline set.

25. A method according to claim 24, wherein for each HARQ timeline set in the multiple HARQ timeline sets, a PSFCH resource subset in the associated PSFCH resource set is determined at least in part based on the time domain position and frequency domain position of the side link transmission, and the HARQ feedback resources of the PSFCH resource subset are at least in part based on the HARQ timeline index, the first UE identifier and the second UE identifier in the HARQ timeline set.

26. The method of claim 16, wherein the sidelink transmission is associated with an unlicensed frequency band.

27. A method of wireless communication performed by a first user equipment (UE), the method comprising: receiving sidelink control information (SCI) from a second UE; receiving a sidelink transmission from the second UE; as well as and sending a hybrid automatic repeat request (HARQ) feedback to the second UE based at least in part on the sidelink transmission, wherein a time slot for sending the HARQ feedback is based at least in part on a HARQ timeline subset indicated by the SCI, and wherein the HARQ timeline subset is included in a plurality of HARQ timelines configured for the sidelink.

28. The method of claim 27, wherein the SCI indicates a number of HARQ timelines associated with the HARQ timeline subset, and wherein the number of HARQ timelines among the plurality of HARQ timelines are used to send the HARQ feedback.

29. The method of claim 27, wherein the SCI indicates a plurality of HARQ timeline code points, and a HARQ timeline code point of the plurality of HARQ timeline code points indicates the HARQ timeline subset.

30. The method of claim 27, wherein the sidelink transmission is associated with an unlicensed frequency band.

Images