WO2025039099A1

WO2025039099A1 - Cyclic prefix extension for sidelink transmissions in shared channel occupancy time

Info

Publication number: WO2025039099A1
Application number: PCT/CN2023/113690
Authority: WO
Inventors: Shaozhen GUO; Changlong Xu; Giovanni Chisci; Chih-Hao Liu; Luanxia YANG; Siyi Chen; Jing Sun; Xiaoxia Zhang; Hao Xu
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2023-08-18
Filing date: 2023-08-18
Publication date: 2025-02-27
Anticipated expiration: 2026-02-18

Abstract

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may select a first cyclic prefix extension (CPE) that reduces a gap, between a previous slot when a transmission by an initiator UE of a channel occupancy time (COT) is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more resource block (RB) sets, and based at least in part on a default CPE not being able to reduce the gap to the size. The UE may attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE. Numerous other aspects are described.

Description

CYCLIC PREFIX EXTENSION FOR SIDELINK TRANSMISSIONS IN SHARED CHANNEL OCCUPANCY TIME

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for using a cyclic prefix extension for sidelink transmissions in a shared channel occupancy time.

BACKGROUND

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, or the like) . 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) .

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

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

SUMMARY

Some aspects described herein relate to a method of wireless communication performed by a user equipment (UE) . The method may include selecting a first cyclic prefix extension (CPE) that reduces a gap, between a previous slot when a transmission by an initiator UE of a channel occupancy time (COT) is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more resource block (RB) sets, and based at least in part on a default CPE not being able to reduce the gap to the size. The method may include attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

Some aspects described herein relate to a method of wireless communication performed by a UE. The method may include selecting a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more RB sets. The method may include attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

Some aspects described herein relate to an apparatus for wireless communication at a UE. The apparatus may include one or more memories and one or more processors coupled to the one or more memories. The one or more processors may be individually or collectively configured to select a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more RB sets, and based at least in part on a default CPE not being able to reduce the gap to the size. The one or more processors may be individually or collectively configured to attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

Some aspects described herein relate to an apparatus for wireless communication at a UE. The apparatus may include one or more memories and one or more processors coupled to the one or more memories. The one or more processors may be individually or collectively configured to select a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more RB sets. The one or more processors may be individually or collectively configured to attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a UE. The set of instructions, when executed by one or more processors of the UE, may cause the UE to select a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more RB sets, and based at least in part on a default CPE not being able to reduce the gap to the size. The set of instructions, when executed by one or more processors of the UE, may cause the UE to attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a UE. The set of instructions, when executed by one or more processors of the UE, may cause the UE to select a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more RB sets. The set of instructions, when executed by one or more processors of the UE, may cause the UE to attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for selecting a first CPE that reduces a gap, between a previous slot when a transmission by another apparatus of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more RB sets, and based at least in part on a default CPE not being able to reduce the gap to the size. The apparatus may include means for attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for selecting a first CPE that reduces a gap, between a previous slot when a transmission by another apparatus of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more RB sets. The apparatus may include means for attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

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

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

While aspects are described in the present disclosure by illustration to some examples, those skilled in the art will understand that such aspects may be implemented in many different arrangements and scenarios. Techniques described herein may be implemented using different platform types, devices, systems, shapes, sizes, and/or packaging arrangements. In some aspects, some aspects may be implemented via integrated chip embodiments or other non-module-component based devices (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail/purchasing devices, medical devices, and/or artificial intelligence devices) . Aspects may be implemented in chip-level components, modular components, non-modular components, non-chip-level components, device-level components, and/or system-level components. Devices incorporating described aspects and features may include additional components and features for implementation and practice of claimed and described aspects. In some aspects, transmission and reception of wireless signals may include one or more components for analog and digital purposes (e.g., hardware components including antennas, radio frequency (RF) chains, power amplifiers, modulators, buffers, processors, interleavers, adders, and/or summers) . It is intended that aspects described herein may be practiced in a wide variety of devices, components, systems, distributed arrangements, and/or end-user devices of varying size, shape, and constitution.

BRIEF DESCRIPTION OF THE DRAWINGS

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

Fig. 1 is a diagram illustrating an example of a wireless network, in accordance with the present disclosure.

Fig. 2 is a diagram illustrating an example of a network node in communication with a user equipment (UE) in a wireless network, in accordance with the present disclosure.

Fig. 3 is a diagram illustrating an example of sidelink communications, in accordance with the present disclosure.

Fig. 4 is a diagram illustrating an example of sidelink communications and access link communications, in accordance with the present disclosure.

Fig. 5 is a diagram illustrating an example of selecting sidelink resources, in accordance with the present disclosure.

Fig. 6 is a diagram illustrating an examples of cycle prefix extensions (CPEs) based on detection of a reservation, in accordance with the present disclosure.

Fig. 7 is a diagram illustrating an example of channel occupancy time (COT) sharing issues, in accordance with the present disclosure.

Fig. 8 is a diagram illustrating an example of a COT sharing offset, in accordance with the present disclosure.

Fig. 9 is a diagram illustrating examples of a gap between sidelink transmissions, in accordance with the present disclosure.

Fig. 10 is a diagram illustrating an example of a shared COT, in accordance with the present disclosure.

Fig. 11 is a diagram illustrating an example of selecting a CPE in a shared COT, in accordance with the present disclosure.

Fig. 12 is a diagram illustrating an example of selecting a CPE in a shared COT, in accordance with the present disclosure.

Fig. 13 is a diagram illustrating an example of selecting a CPE in a shared COT, in accordance with the present disclosure.

Fig. 14 is a diagram illustrating examples of selecting a CPE in a shared COT, in accordance with the present disclosure.

Fig. 15 is a diagram illustrating examples of selecting a CPE in a shared COT, in accordance with the present disclosure.

Fig. 16 is a diagram illustrating examples of selecting a CPE in a shared COT, in accordance with the present disclosure.

Fig. 17 is a diagram illustrating an example of selecting a CPE based on one or more conditions, in accordance with the present disclosure.

Fig. 18 is a diagram illustrating examples of selecting a CPE in a shared COT, in accordance with the present disclosure.

Fig. 19 is a diagram illustrating an example process performed, in some aspects, at a UE or an apparatus of a UE, in accordance with the present disclosure.

Fig. 20 is a diagram illustrating an example process performed, in some aspects, at a UE or an apparatus of a UE, in accordance with the present disclosure.

Fig. 21 is a diagram of an example apparatus for wireless communication, in accordance with the present disclosure.

DETAILED DESCRIPTION

User equipments (UEs) may operate in unlicensed sidelink (SL-U) . If a UE (e.g., channel occupancy time (COT) initiator) determines that a channel is clear, the UE may treat the channel as clear for a maximum duration of time, or a COT. If the UE does not need to use the whole COT for a transmission or reception, the UE may share the COT with another UE (e.g., responding UE) . The responding UE may transmit a sidelink communication that follows a sidelink communication by the COT initiator UE after a gap as follows. 1) If the gap is at least 25 microseconds (μs) , the responding UE may transmit the sidelink communication on the shared channel after performing Type 2A sidelink channel access procedures. 2) If the gap is equal to 16 μs, the responding UE may transmit the sidelink transmission on the shared channel after performing Type 2B sidelink channel access procedures. 3) If the gap is up to 16 μs and the transmission is limited to 584 μs, the responding UE may transmit the sidelink transmission on the channel after performing Type 2C sidelink channel access.

In some examples, a responding UE may transmit a cyclic prefix extension (CPE) , which includes a start of a transmission in a gap between a first communication and a second communication. The UE may transmit the CPE in order to start transmission at a starting position that is before a scheduled first symbol of the second communication. The COT initiator UE may transmit a communication in a first slot. There may be a gap between the first slot and a second slot. If the gap is greater than a size that protects transmissions in a shared COT, the responding UE may need to perform Type 2A channel access. If the gap is the size (or no greater than the size) that protects sidelink transmissions in a shared COT, the UE may transmit a communication in the second slot using Type 2B or 2C channel access.

In some aspects, a UE may operate in different cases. For Case 1, if the default CPE cannot ensure that a size of a gap is less than or equal to 16 microseconds (μs) , Type 2B and Type 2C cannot be used for UE0, even if UE0 detects initiator UE’s transmission is terminated in the previous slot. For Case 2, if the randomly selected CPE cannot ensure that the size of the gap is less than or equal to 16 μs, Type 2B and Type 2C cannot be used for UE0, even if UE0 detects the UE initiator’s transmission is terminated in the previous slot. If the size of the gap cannot be ensured for the default CPE or the selected CPE, some UE transmissions may be blocked, including for the UE initiator or for a high priority UE.

A UE may intend to transmit a communication on a current slot. According to various aspects described herein, the UE may select a first CPE that ensures that a size of the gap (e.g., ≤ 16 μs) between a previous slot and the current slot protects consecutive sidelink transmissions in a shared COT (transmissions in consecutive slots) , based on one or more conditions related to whether a transmission or reservation is detected. The UE may select the first CPE based at least in part on detecting a transmission or reservation in a current slot and detecting that a UE initiator of the COT terminated a transmission in a previous slot. The UE may select the first CPE further based at least in part on the default CPE for the UE not ensuring that the gap is the size that protects sidelink transmissions in a shared COT.

By selecting a CPE that ensures that gap when the default CPE does not and when a transmission or reservation is detected, the UE may protect sidelink transmissions in a shared COT. Protecting sidelink transmissions in a shared COT may improve the resource utilization and conserve signaling resources.

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

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

While aspects may be described herein using terminology commonly associated with a 5G or New Radio (NR) radio access technology (RAT) , aspects of the present disclosure can be applied to other RATs, such as a 3G RAT, a 4G RAT, and/or a RAT subsequent to 5G (e.g., 6G) .

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

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

In some examples, a network node 110 may provide communication coverage for a particular geographic area. In the Third Generation Partnership Project (3GPP) , the term “cell” can refer to a coverage area of a network node 110 and/or a network node subsystem serving this coverage area, depending on the context in which the term is used. A network node 110 may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another type of cell. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs 120 with service subscriptions. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs 120 with service subscriptions. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs 120 having association with the femto cell (e.g., UEs 120 in a closed subscriber group (CSG) ) . A network node 110 for a macro cell may be referred to as a macro network node. A network node 110 for a pico cell may be referred to as a pico network node. A network node 110 for a femto cell may be referred to as a femto network node or an in-home network node. In the example shown in Fig. 1, the network node 110a may be a macro network node for a macro cell 102a, the network node 110b may be a pico network node for a pico cell 102b, and the network node 110c may be a femto network node for a femto cell 102c. A network node may support one or multiple (e.g., three) cells. In some examples, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a network node 110 that is mobile (e.g., a mobile network node) .

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

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

The wireless network 100 may be a heterogeneous network that includes network nodes 110 of different types, such as macro network nodes, pico network nodes, femto network nodes, relay network nodes, or the like. 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. In some aspects, macro network nodes may have a high transmit power level (e.g., 5 to 40 watts) whereas pico network nodes, femto network nodes, and relay network nodes may have lower transmit power levels (e.g., 0.1 to 2 watts) .

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

The UEs 120 may be dispersed throughout the wireless network 100, and each UE 120 may be stationary or mobile. A UE 120 may include, in some aspects, an access terminal, a terminal, a mobile station, and/or a subscriber unit. A UE 120 may 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, 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 vehicular component or sensor, a smart meter/sensor, industrial manufacturing equipment, a global positioning system device, a UE function of a network node, and/or any other suitable device that is configured to communicate via a wireless or wired medium.

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

In general, any number of wireless networks 100 may be deployed in a given geographic area. Each wireless network 100 may support a particular RAT and may operate on one or more frequencies. A RAT may be referred to as a radio technology, an air interface, or the like. A frequency may be referred to as a carrier, a frequency channel, or the like. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

In some examples, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may communicate directly using one or more sidelink channels (e.g., without using a network node 110 as an intermediary to communicate with one another) . In some aspects, the UEs 120 may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, or a vehicle-to-pedestrian (V2P) protocol) , and/or a mesh network. In such examples, a UE 120 may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by the network node 110.

Devices of the wireless network 100 may communicate using the electromagnetic spectrum, which may be subdivided by frequency or wavelength into various classes, bands, channels, or the like. In some aspects, 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 referred to (interchangeably) as a “Sub-6 GHz” band in various documents and articles. A similar nomenclature issue sometimes occurs with regard to FR2, which is often referred to (interchangeably) as a “millimeter wave” band in documents and articles, despite being different from the extremely high frequency (EHF) band (30 GHz –300 GHz) which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band.

The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Recent 5G NR studies have identified an operating band for these mid-band frequencies as frequency range designation FR3 (7.125 GHz –24.25 GHz) . Frequency bands falling within FR3 may inherit FR1 characteristics and/or FR2 characteristics, and thus may effectively extend features of FR1 and/or FR2 into mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operation beyond 52.6 GHz. In some aspects, three higher operating bands have been identified as frequency range designations FR4a or FR4-1 (52.6 GHz –71 GHz) , FR4 (52.6 GHz –114.25 GHz) , and FR5 (114.25 GHz –300 GHz) . Each of these higher frequency bands falls within the EHF band.

With the above examples in mind, unless specifically stated otherwise, it should be understood that the term “sub-6 GHz” or the like, if used herein, may broadly represent frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. Further, unless specifically stated otherwise, it should be understood that the term “millimeter wave” or the like, if used herein, may broadly represent frequencies that may include mid-band frequencies, may be within FR2, FR4, 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 techniques described herein are applicable to those modified frequency ranges.

In some aspects, a UE (e.g., UE 120) may include a communication manager 140. As described in more detail elsewhere herein, the communication manager 140 may select a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more resource block (RB) sets, and based at least in part on a default CPE not being able to reduce the gap to the size. The communication manager 140 may attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

In some aspects, the communication manager 140 may select a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more RB sets. The communication manager 140 may attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE. Additionally, or alternatively, the communication manager 140 may perform one or more other operations described herein.

As indicated above, Fig. 1 is provided as an example. Other examples may differ from what is described with regard to Fig. 1.

Fig. 2 is a diagram illustrating an example 200 of a network node 110 in communication with a UE 120 in a wireless network 100, in accordance with the present disclosure. The network node 110 may be equipped with a set of antennas 234a through 234t, such as T antennas (T ≥ 1) . The UE 120 may be equipped with a set of antennas 252a through 252r, such as R antennas (R ≥ 1) . The network node 110 of example 200 includes one or more radio frequency components, such as antennas 234 and a modem 232. In some examples, a network node 110 may include an interface, a communication component, or another component that facilitates communication with the UE 120 or another network node. Some network nodes 110 may not include radio frequency components that facilitate direct communication with the UE 120, such as one or more CUs, or one or more DUs.

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

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

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

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

On the uplink, at the UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information (e.g., for reports that include RSRP, RSSI, RSRQ, and/or CQI) from the controller/processor 280. The transmit processor 264 may generate reference symbols for one or more reference signals. The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by the modems 254 (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 the antenna (s) 252, the modem (s) 254, the MIMO detector 256, the receive processor 258, the transmit processor 264, and/or the TX MIMO processor 266. The transceiver may be used by a processor (e.g., the controller/processor 280) and the memory 282 to perform aspects of any of the methods described herein (e.g., with reference to Figs. 3-21) .

At the network node 110, the uplink signals from UE 120 and/or other UEs may be received by the antennas 234, processed by the modem 232 (e.g., a demodulator component, shown as DEMOD, of the modem 232) , detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by the UE 120. The receive processor 238 may provide the decoded data to a data sink 239 and provide the decoded control information to the controller/processor 240. The network node 110 may include a communication unit 244 and may communicate with the network controller 130 via the communication unit 244. The network node 110 may include a scheduler 246 to schedule one or more UEs 120 for downlink and/or uplink communications. In some examples, the modem 232 of the network node 110 may include a modulator and a demodulator. In some examples, the network node 110 includes a transceiver. The transceiver may include any combination of the antenna (s) 234, the modem (s) 232, the MIMO detector 236, the receive processor 238, the transmit processor 220, and/or the TX MIMO processor 230. The transceiver may be used by a processor (e.g., the controller/processor 240) and the memory 242 to perform aspects of any of the methods described herein (e.g., with reference to Figs. 3-21) .

A controller/processor 240 of the network node 110, the controller/processor 280 of the UE 120, and/or any other component (s) of Fig. 2 may perform one or more techniques associated with selecting a CPE in a COT, as described in more detail elsewhere herein. In some aspects, the controller/processor 240 of the network node 110, the controller/processor 280 of the UE 120, and/or any other component (s) of Fig. 2 may perform or direct operations of, in some aspects, process 1900 of Fig. 19, process 2000 of Fig. 12, and/or other processes as described herein. The memory 242 and the memory 282 may store data and program codes for the network node 110 and the UE 120, respectively. In some examples, the memory 242 and/or the 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. In some aspects, the one or more instructions, when executed (e.g., directly, or after compiling, converting, and/or interpreting) by one or more processors of the network node 110 and/or the UE 120, may cause the one or more processors, the UE 120, and/or the network node 110 to perform or direct operations of, in some aspects, process 1900 of Fig. 19, process 2000 of Fig. 12. In some examples, executing instructions may include running the instructions, converting the instructions, compiling the instructions, and/or interpreting the instructions, among other examples.

In some aspects, a UE (e.g., a UE 120) includes means for selecting a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more RB sets, and based at least in part on a default CPE not being able to reduce the gap to the size; and/or means for attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE. The means for the UE to perform operations described herein may include, in some aspects, one or more of communication manager 140, antenna 252, modem 254, MIMO detector 256, receive processor 258, transmit processor 264, TX MIMO processor 266, controller/processor 280, or memory 282.

In some aspects, the UE includes means for selecting a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more RB sets; and/or means for attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

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

While blocks in Fig. 2 are illustrated as distinct components, the functions described above with respect to the blocks may be implemented in a single hardware, software, or combination component or in various combinations of components. In some aspects, the functions 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.

As indicated above, Fig. 2 is provided as an example. Other examples may differ from what is described with regard to Fig. 2.

Deployment of communication systems, such as 5G NR systems, may be arranged in multiple manners with various components or constituent parts. In a 5G NR system, or network, a network node, a network entity, a mobility element of a network, a RAN node, a core network node, a network element, a base station, or a network equipment may be implemented in an aggregated or disaggregated architecture. In some aspects, a base station (such as a Node B (NB) , an evolved NB (eNB) , an NR base station, a 5G NB, an access point (AP) , a TRP, or a cell, among other examples) , or one or more units (or one or more components) performing base station functionality, may be implemented as an aggregated base station (also known as a standalone base station or a monolithic base station) or a disaggregated base station. “Network entity” or “network node” may refer to a disaggregated base station, or to one or more units of a disaggregated base station (such as one or more CUs, one or more DUs, one or more RUs, or a combination thereof) .

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

Base station-type operation or network design may consider aggregation characteristics of base station functionality. In some aspects, disaggregated base stations may be utilized in an IAB network, an open radio access network (O-RAN (such as the network configuration sponsored by the O-RAN Alliance) ) , or a virtualized radio access network (vRAN, also known as a cloud radio access network (C-RAN) ) to facilitate scaling of communication systems by separating base station functionality into one or more units that can be individually deployed. A disaggregated base station may include functionality implemented across two or more units at various physical locations, as well as functionality implemented for at least one unit virtually, which can enable flexibility in network design. The various units of the disaggregated base station can be configured for wired or wireless communication with at least one other unit of the disaggregated base station.

Fig. 3 is a diagram illustrating an example 300 of sidelink communications, in accordance with the present disclosure.

As shown in Fig. 3, a first UE 305-1 may communicate with a second UE 305-2 (and one or more other UEs 305) via one or more sidelink channels 310. The UEs 305-1 and 305-2 may communicate using the one or more sidelink channels 310 for P2P communications, D2D communications, V2X communications (e.g., which may include V2V communications, V2I communications, and/or V2P communications) and/or mesh networking. In some aspects, the UEs 305 (e.g., UE 305-1 and/or UE 305-2) may correspond to one or more other UEs described elsewhere herein, such as UE 120. In some aspects, the one or more sidelink channels 310 may use a PC5 interface and/or may operate in a high frequency band (e.g., the 5.9 GHz band) . Additionally, or alternatively, the UEs 305 may synchronize timing of transmission time intervals (TTIs) (e.g., frames, subframes, slots, or symbols) using global navigation satellite system (GNSS) timing.

As further shown in Fig. 3, the one or more sidelink channels 310 may include a physical sidelink control channel (PSCCH) 315, a physical sidelink shared channel (PSSCH) 320, and/or a physical sidelink feedback channel (PSFCH) 325. The PSCCH 315 may be used to communicate control information, similar to a physical downlink control channel (PDCCH) and/or a physical uplink control channel (PUCCH) used for cellular communications with a network node 110 via an access link or an access channel. The PSSCH 320 may be used to communicate data, similar to a physical downlink shared channel (PDSCH) and/or a physical uplink shared channel (PUSCH) used for cellular communications with a network node 110 via an access link or an access channel. In some aspects, the PSCCH 315 may carry sidelink control information (SCI) 330, which may indicate various control information used for sidelink communications, such as one or more resources (e.g., time resources, frequency resources, and/or spatial resources) where a transport block (TB) 335 may be carried on the PSSCH 320. The TB 335 may include data. The PSFCH 325 may be used to communicate sidelink feedback 340, such as hybrid automatic repeat request (HARQ) feedback (e.g., acknowledgement or negative acknowledgement (ACK/NACK) information) , transmit power control (TPC) , and/or a scheduling request (SR) .

Although shown on the PSCCH 315, in some aspects, the SCI 330 may include multiple communications in different stages, such as a first stage SCI (SCI-1) and a second stage SCI (SCI-2) . The SCI-1 may be transmitted on the PSCCH 315. The SCI-2 may be transmitted on the PSSCH 320. The SCI-1 may include, in some aspects, an indication of one or more resources (e.g., time resources, frequency resources, and/or spatial resources) on the PSSCH 320, information for decoding sidelink communications on the PSSCH, a quality of service (QoS) priority value, a resource reservation period, a PSSCH DMRS pattern, an SCI format for the SCI-2, a beta offset for the SCI-2, a quantity of PSSCH DMRS ports, and/or an MCS. The SCI-2 may include information associated with data transmissions on the PSSCH 320, such as a HARQ process ID, a new data indicator (NDI) , a source identifier, a destination identifier, and/or a channel state information (CSI) report trigger.

In some aspects, the one or more sidelink channels 310 may use resource pools. In some aspects, a scheduling assignment (e.g., included in SCI 330) may be transmitted in sub-channels using specific RBs across time. In some aspects, data transmissions (e.g., on the PSSCH 320) associated with a scheduling assignment may occupy adjacent RBs in the same subframe as the scheduling assignment (e.g., using frequency division multiplexing) . In some aspects, a scheduling assignment and associated data transmissions are not transmitted on adjacent RBs.

In some aspects, a UE 305 may operate using a sidelink transmission mode (e.g., Mode 1) where resource selection and/or scheduling is performed by a network node 110 (e.g., a base station, a CU, or a DU) . In some aspects, the UE 305 may receive a grant (e.g., in downlink control information (DCI) or in a radio resource control (RRC) message, such as for configured grants) from the network node 110 (e.g., directly or via one or more network nodes) for sidelink channel access and/or scheduling. In some aspects, a UE 305 may operate using a transmission mode (e.g., Mode 2) where resource selection and/or scheduling is performed by the UE 305 (e.g., rather than a network node 110) . In some aspects, the UE 305 may perform resource selection and/or scheduling by sensing channel availability for transmissions. In some aspects, the UE 305 may measure an RSSI parameter (e.g., a sidelink-RSSI (S-RSSI) parameter) associated with various sidelink channels, may measure an RSRP parameter (e.g., a PSSCH-RSRP parameter) associated with various sidelink channels, and/or may measure an RSRQ parameter (e.g., a PSSCH-RSRQ parameter) associated with various sidelink channels, and may select a channel for transmission of a sidelink communication based at least in part on the measurement (s) .

Additionally, or alternatively, the UE 305 may perform resource selection and/or scheduling using SCI 330 received in the PSCCH 315, which may indicate occupied resources and/or channel parameters. Additionally, or alternatively, the UE 305 may perform resource selection and/or scheduling by determining a channel busy ratio (CBR) associated with various sidelink channels, which may be used for rate control (e.g., by indicating a maximum number of resource blocks that the UE 305 can use for a particular set of subframes) .

In the transmission mode where resource selection and/or scheduling is performed by a UE 305, the UE 305 may generate sidelink grants, and may transmit the grants in SCI 330. A sidelink grant may indicate, in some aspects, one or more parameters (e.g., transmission parameters) to be used for an upcoming sidelink transmission, such as one or more resource blocks to be used for the upcoming sidelink transmission on the PSSCH 320 (e.g., for TBs 335) , one or more subframes to be used for the upcoming sidelink transmission, and/or an MCS to be used for the upcoming sidelink transmission. In some aspects, a UE 305 may generate a sidelink grant that indicates one or more parameters for semi-persistent scheduling (SPS) , such as a periodicity of a sidelink transmission. Additionally, or alternatively, the UE 305 may generate a sidelink grant for event-driven scheduling, such as for an on-demand sidelink message.

As indicated above, Fig. 3 is provided as an example. Other examples may differ from what is described with respect to Fig. 3.

Fig. 4 is a diagram illustrating an example 400 of sidelink communications and access link communications, in accordance with the present disclosure.

As shown in Fig. 4, a transmitter (Tx) /receiver (Rx) UE 405 and an Rx/Tx UE 410 may communicate with one another via a sidelink, as described above in connection with Fig. 3. As further shown, in some sidelink modes, a network node 110 may communicate with the Tx/Rx UE 405 (e.g., directly or via one or more network nodes) , such as via a first access link. Additionally, or alternatively, in some sidelink modes, the network node 110 may communicate with the Rx/Tx UE 410 (e.g., directly or via one or more network nodes) , such as via a first access link. The Tx/Rx UE 405 and/or the Rx/Tx UE 410 may correspond to one or more UEs described elsewhere herein, such as the UE 120 of Fig. 1. Thus, a direct link between UEs 120 (e.g., via a PC5 interface) may be referred to as a sidelink, and a direct link between a network 110 and a UE 120 (e.g., via a Uu interface) may be referred to as an access link. Sidelink communications may be transmitted via the sidelink, and access link communications may be transmitted via the access link. An access link communication may be either a downlink communication (from a network node 110 to a UE 120) or an uplink communication (from a UE 120 to a network node 110) .

As indicated above, Fig. 4 is provided as an example. Other examples may differ from what is described with respect to Fig. 4.

Fig. 5 is a diagram illustrating an example 500 of selecting sidelink resources, in accordance with the present disclosure. Example 500 shows a UE 502 (e.g., a UE 120) that may receive communications on a sidelink channel from other UEs, such as UE 504, UE 506, and/or UE 508.

As described in connection with Fig. 5, UE 504 is a transmitting UE that is transmitting communications to UE 502, which is a receiving UE. UE 504 may use a report from UE 502, which may act as a reporting UE that reports available sidelink resources, preferred sidelink resources, non-preferred sidelink resources, or sidelink resource conflicts. Example 500 shows an availability report from UE 502 to UE 504 and a communication from UE 504 to UE 502.

If UE 504 is to transmit a communication to UE 502, UE 504 may sense the sidelink channel in a sensing window to determine which sidelink resources (e.g., subcarriers, subchannels) are available. UE 504 may use a listen-before-talk (LBT) procedure to sense the channel. The LBT procedure maybe a Type 1 LBT procedure, where UE 504 listens for multiple slots (e.g., 9 milliseconds (ms) ) and uses a counter. A sidelink resource may be considered available if the sidelink resource was clear or had a signal energy (e.g., RSRP) that satisfied an availability threshold (e.g., measured interference or energy on the channel is lower than a maximum decibel-milliwatts (dBm) or dB, RSRP threshold) . The availability threshold may be configured or preconfigured per transmission priority and receive priority pair. UE 504 may measure DMRSs on a PSCCH or a PSSCH, according to a configuration.

In some aspects, UE 504 may prepare to transmit a communication to UE 502. UE 504 may have already sensed previous sidelink resources and successfully decoded SCI from UE 506 and UE 508. UE 504 may try to reserve sidelink resources, and thus may check the availability of the future sidelink resources reserved by UE 506 and UE 508 by sensing the sidelink channel in the sensing window. UE 504 may measure an RSRP of a signal from UE 508 in sidelink resource 510, and an RSRP of a signal from UE 506 in sidelink resource 512. If an observed RSRP (RSRP projection) satisfies the RSRP threshold (e.g., is lower than a maximum RSRP) , the corresponding sidelink resource may be available for reservations by UE 504. UE 504 may reserve the sidelink resource (which may be a random selection from available resources) . In some aspects, UE 504 may select and reserve sidelink resource 514 for transmission. This may be in a time slot after which UE 506 and UE 508 had used sidelink resources, and UE 504 may have sensed these sidelink resources earlier. UE 504 may select and reserve sidelink resources only upon reaching a threshold level (e.g., 20%, 30%, or 50%availability) . UE 504 may increase or decrease the RSRP threshold as necessary to arrive at the threshold level. UE 504 may select and reserve sidelink resources in the current slot and up to two (or more) future slots. Reservations may be aperiodic or periodic (e.g., SCI signals period between 0 ms and 1000 ms) . Periodic resource reservation may be disabled.

There may be a resource selection trigger to trigger selection of sidelink resources after a processing time T_proc, ₀, and before another processing time T_proc, ₁ before a resource selection window from which sidelink resources are available. The resource selection window may be a time window from which sidelink resources may be selected, and the resource selection window may extend for a remaining packet delay budget (PDB) .

As indicated above, Fig. 5 is provided as an example. Other examples may differ from what is described with regard to Fig. 5.

Fig. 6 is a diagram illustrating an examples 600, 602, and 604 of CPEs based on detection of a reservation, in accordance with the present disclosure.

When a UE performs Type 1 channel access to initiate a COT for a PSCCH/PSSCH transmission, one of two schemes may be used. In a first scheme, the UE selects a preconfigured default CPE with its default starting position for a communication in a slot. In a second scheme, the UE selects a candidate CPE, with its candidate starting position, from among one or multiple CPE starting candidates, for the slot. The candidate CPEs may be preconfigured per priority of the PSCCH/PSSCH per resource pool. In some aspects, if a resource reservation is transmitted or resource reservations are detected for the slot and the one or more RB sets of the intended PSCCH/PSSCH transmission, the UE may apply the first scheme. Otherwise, the UE may apply the second scheme.

Example 600 shows SCI₀ and SCI₁ that indicate reservations. If reservations are detected, the UE may use a default CPE for a communication in a slot and an RB set. Example 602 shows that if reservations are detected for the same sidelink resource (same slot and same RB set) , and an RSRP threshold is satisfied (e.g., signal strength less than the RSRP threshold) , the default CPE may be used for the communications in the slot and the RB set, because the signals are not enough for inter-UE blocking.

Example 604 shows that if a reservation is not detected, the UE may randomly select a CPE per priority to avoid inter-UE collisions. The mapping of one or multiple CPE starting positions per priority can be up to preconfiguration. In some aspects, the priority may be a Layer 1 (L1) priority or a channel access priority class (CAPC) priority.

Fig. 7 is a diagram illustrating an example 700 of COT sharing issues, in accordance with the present disclosure.

UEs may operate in unlicensed sidelink (SL-U) . If a first UE (UE1) determines that a channel is clear, UE1 may treat the channel as clear for a maximum duration of time, or a COT. If UE1 does not need to use the whole COT for a PSSCH transmission or reception, UE1 may share the COT with another UE, such as with a second UE (UE2) . UE1 may indicate RBs and a time duration for the COT. UE1 may be a COT initiator that performs an LBT procedure and starts the COT. UE1 may transmit data to UE2 in a PSSCH communication during the COT. UE2 may be a COT responder and may provide a PSFCH communication to UE1, in response to the PSSCH communication, during the COT. UE2 may be considered to be a PSFCH transmitter. UE2 may perform a type 2 LBT procedure, which is a “one-shot” channel sensing of a much shorter duration (e.g., 16 μs) than a duration of a Type 1 LBT procedure.

A COT interruption gap duration between communications is expected to be 25 μs. If UE1 starts a transmission within the COT interruption gap, UE1 maintains the COT and UE2 is not able to transmit. If UE1 does not start a transmission within the COT interruption gap, UE1 does not maintain the COT and UE2 may transmit. UE2 may perform a Type 2A channel access (16 μs) before transmitting.

Example 700 shows a COT with slots in which UE1 (initiator) intends to transmit. UE1 may share the COT with UE2 (responder) and provide UE2 an indication of a COT remaining duration in COT sharing indication (COT-SI) . If the time-domain information for the shared COT is provided, it is still unclear how UE1’s transmissions are to be protected. That is, it is unclear in which portion of the remaining COT UE2 can transmit. If UE2 can attempt to access the channel with LBT Type 2 and transmit anywhere in the COT (after decoding COT-SI and before the COT end time marked by the COT remaining duration) , there is a chance that UE2 would preempt the channel from being used by UE1. As shown in example 700, UE1 may drop transmissions for two slots due to a reevaluation or preemption check by UE1 that leads to reselection. However, UE2 can access the channel and start a sidelink transmission burst that blocks the future re-access of UE1. The next two slots are not reserved by either UE1 or UE2 and thus UE2 may keep transmitting its burst, which prevents UE1 from resuming transmissions in its own COT (failed Type 2 access by UE1) . If UE1 cannot transmit in its own COT, UE1’s communications will degrade and latency will increase.

As indicated above, Fig. 7 is provided as an example. Other examples may differ from what is described with regard to Fig. 7.

Fig. 8 is a diagram illustrating an example 800 of a COT sharing offset, in accordance with the present disclosure.

In a COT sharing framework in unlicensed NR (NR-U) , UE1 may perform Type 1 LBT and obtain a COT. UE1 may share the COT and indicate COT-SI to UE2 that includes an offset and a duration of the shared COT. UE2 may not access the shared COT before the offset in order to protect UE1’s ability to access the shared COT. Example 800 shows a shared COT 802 of UE1 with a region before the offset 804 (UE1 region) that UE2 cannot access and a region after the offset 804 (UE2 region) that UE2 can access. UE1 may access (perform Type 2 LBT) and transmit in the shared COT 802 in the UE1 region and the UE2 region. UE2 may access (Type 2 LBT) and transmit in the shared COT 802 only in the UE2 region. A transmission within the shared COT 802 may mean that the transmission is within the RB sets (20 MHz LBT channels) obtained by the Type 1 channel access (or Cat 4 LBT) performed by UE1. In the time domain, the transmission is located between the COT-SI and the maximum COT duration. Different durations may be obtained by performing Type 1 channel access associated with a given CAPC. Higher priority maps to faster channel access in terms of a smaller random counter and a shorter COT duration.

As indicated above, Fig. 8 is provided as an example. Other examples may differ from what is described with regard to Fig. 8.

Fig. 9 is a diagram illustrating examples 900, 910, and 920 of a gap between sidelink transmissions, in accordance with the present disclosure.

In some examples, a UE may transmit a CPE, which includes a start of a transmission in a gap between a first communication and a second communication. The UE may transmit the CPE in order to start transmission at a starting position that is before a scheduled first symbol of the second communication. There may be one or more CPE starting positions before a starting position for a sidelink synchronization signal block (S-SSB) , a PSFCH communication, or another physical sidelink channel communication (e.g., PSCCH, PSSCH) . The CPE starting position may be configured or indicated.

A CPE may be transmitted from a CPE starting position before a sidelink transmission for the following two options: within the symbol just before the next automatic gain control (AGC) symbol; within the symbol just before the next AGC symbol for 15 kilohertz (kHz) subcarrier spacing (SCS) ; or within at most 2 symbols just before the next AGC symbol for 30 or 60 kHz SCS.

In some examples, UE2 may select a CPE starting position that is later than a CPE starting position of UE1. This may help UE1 to better succeed in a channel access in its own shared COT. In some aspects, the starting position of a first CPE may be earlier than the starting position of a second CPE. In some aspects, the LBT may be Type 2A (16 μs) , Type 2B (25 μs) , or Type 2C (without a CPE and at the start of the next symbol) . The Type 2A LBT may be before the AGC symbol. If a gap is 16 μs and limited to 584 μs, the responding UE may transmit the sidelink transmission on the channel after performing a Type 2C sidelink channel access. If the UE detects that the initiator terminated its transmission in the previous slot and if the selected CPE satisfies a 16 μs gap from the end of the COT initiator’s transmission, the UE may upgrade Type 2A to Type 2B or Type 2C.

Example 900 shows an example of a COT 902 that is initiated by UE1 (Type 1 access) and shared with UE2. UE1 may transmit a communication (PSSCH or PSCCH) in a first slot 904. UE1 or UE2 may perform Type 2 access to transmit a communication in a second slot 906. There may be a gap 908 between the first slot 904 and the second slot 906. If the gap 908 is greater than a size (e.g., 16 μs, 25 μs) that protects consecutive transmissions in the COT 902, UE2 may obtain access and transmit in a communication in the second slot 906, preventing UE1 from transmitting in the second slot 906. If the gap 908 is the size (or no greater than the size) that protects consecutive transmissions, UE1 may transmit a communication in the second slot 906 without being preempted by UE2. That is, UE1 may maintain the COT for multiple consecutive slot transmission (MCSt) .

Example 910 shows an example of UE1 transmitting a CPE 912 in the COT 902 to reduce the size of the gap 908 to a size that protects consecutive transmissions by UE1. The CPE 912 may be a size of one or two symbols, in some aspects. In some examples, the CPE 912 may be a default CPE with a configured size and starting position. The default CPE may not reduce the gap 908 to the size that protects consecutive transmissions.

In some examples, the CPE 912 may be one of multiple candidate starting positions. Starting positions may vary based at least in part on an SCS. In some aspects, for 15 kHz SCS, a set of values for candidate CPE positions may include values {T_{sym_1}+16μs, T_{sym_1}+25μs, T_{sym_1}+34μs, T_{sym_1}+43μs, T_{sym_1}+52μs, T_{sym_1}+61μs, T_{sym_0}} , where T_{sym_0} is the starting position of the next AGC symbol (when the CPE starting position is T_{sym_0}, the CPE length is 0) , T_{sym_1} is the starting position of the first symbol just before the next AGC symbol, and T_{sym_2} is the starting position of the second symbol just before the next AGC symbol. For 30 kHz SCS, the set of values for a CPE window of one-symbol length is {T_{sym_1}+16μs, T_{sym_1}+25μs, T_{sym_0}} . For 30kHz SCS, the set of values for a CPE window of two-symbol length is {T_{sym_2}+16μs, T_{sym_2}+25μs, T_{sym_2}+34μs, T_{sym_2}+43μs, T_{sym_2}+52μs, T_{sym_2}+61μs, T_{sym_0}} . For 60 kHz SCS, the set of values for CPE window of one-symbol length is {T_{sym_1}+16μs, T_{sym_0}} . For 60 kHz SCS, the set of values for CPE window of two-symbol length is {T_{sym_2}+16μs, T_{sym_2}+25μs, T_{sym_0}} . Example 920 shows UE1 transmitting a CPE 922 with a starting position that ensures that the gap 908 is reduced to the size that protects consecutive transmissions.

In some examples, UE1 may follow the first scheme or the second scheme. In the first scheme, UE1 may select a preconfigured default CPE, with a default CPE starting position. In the second scheme, UE1 may use a CPE with a starting position that is randomly selected among multiple candidate CPEs with CPE starting positions. One or more candidate CPEs may be mapped to a priority for transmission. In some examples, UE1 may only use a preconfigured default CPE.

UE1 may have a transmission in the second slot 906 that has a different priority than a transmission by UE2. UE1’s transmission may have a greater priority, the same priority, or a lower priority. In examples 900, 910, and 920, UE1 initiates the COT 902. In other examples, UE1 may respond to a COT initiated by UE2.

As indicated above, Fig. 9 is provided as an example. Other examples may differ from what is described with regard to Fig. 9.

Fig. 10 is a diagram illustrating an example 1000 of a shared COT 1002, in accordance with the present disclosure. UE1 may be a COT initiator. UE0 may receive COT-SI from UE1 to share the COT starting from slot n + 2, and UE0 may prepare to transmit starting from slot n + 2 in the COT 1002 initiated by UE1. UE2 may be a COT initiator or may transmit in the COT 1002 initiated by UE1 or in another COT initiated by another UE.

For the COT 1002, UE1 may initiate the COT 1002 in slot n and then share the COT 1002 with UE0 in slot n + 2. UE2 may initiate a COT in slot n + 2 or UE2 may use the COT 1002 in slot n + 2. If a reservation is transmitted or detected for slot n + 2 and the one or more RB sets of UE0’s intended transmission, UE0 may select a default CPE 1004 (this is Case 1 in Fig. 10) . If a reservation is not transmitted or detected for slot n + 2 and the one or more RB sets of UE0’s intended transmission, UE0 may randomly select a CPE 1006 from a set of multiple CPEs that are preconfigured per priority of the PSCCH/PSSCH (this is Case 2 in Fig. 10) . For a priority value of p0, a set of CPEs may be {T_{sym_1}+16μs, T_{sym_1}+25μs} . For a priority value of p1, a set of CPEs may be p2: {T_{sym_1}+34μs, T_{sym_1}+43μs} .

For Case 1, if the default CPE 1004 cannot ensure that a size of a gap 1008 is less than or equal to 16 μs, Type 2B and Type 2C cannot be used for UE0, even if UE0 detects initiator UE’s transmission is terminated in the previous slot. For Case 2, if the randomly selected CPE cannot ensure that the size of the gap 1008 is less than or equal to 16 μs, Type 2B and Type 2C cannot be used for UE0, even if UE0 detects the UE initiator’s transmission is terminated in the previous slot. If the size of the gap 1008 cannot be ensured for the default CPE 1004 or the selected CPE 1006, UE0 may fail to access the shared COT since Type 2B or 2C cannot be used. Failed access may increase latency and waste signaling resources.

As indicated above, Fig. 10 is provided as an example. Other examples may differ from what is described with regard to Fig. 10.

Fig. 11 is a diagram illustrating an example 1100 of selecting a CPE in a shared COT, in accordance with the present disclosure.

A UE may intend to transmit a communication on a PSCCH or PSSCH in a current slot. According to various aspects described herein, the UE may select a first CPE that ensures that a size of the gap (e.g., ≤ 16 μs) between a previous slot and the current slot protects sidelink transmissions in a shared COT (transmissions in consecutive slots) , based on one or more conditions related to whether a transmission or reservation is detected. The UE may select the first CPE based at least in part on detecting a transmission or reservation in a current slot and detecting that a UE initiator of the COT terminated a transmission in a previous slot. The UE may select the first CPE further based at least in part on the default CPE for the UE not ensuring that the gap is the size that protects sidelink transmissions in a shared COT. The UE may receive COT-SI from the initiator COT (UE1) and intend to transmit at the start of the shared COT region (e.g., start from the slot indicated by the offset parameter in COT-SI) . UE0 may transmit a communication with the CPE 1104 starting from a slot that is the first slot after offset 1110, where UE0 is allowed to transmit. By selecting a CPE that ensures that gap when the default CPE does not and when a transmission or reservation is detected, the UE0 may protect sidelink transmissions in the shared COT. Protecting sidelink transmissions in the shared COT may improve the resource utilization and thus reduce latency and conserve signaling resources.

Example 1102 shows a CPE 1112 that ensures that the gap is reduced for UE2 to the size that protects consecutive sidelink transmissions in a shared COT. Example 1102 also shows that UE2 intends to transmit in a shared COT of UEX starting from slot n + 2, which is the first slot after the indicated offset The UEs may detect that UEX terminated its transmission in slot n + 1, where UEX is a COT initiator, which can be the same as UE1 or different than UE1.

As indicated above, Fig. 11 is provided as an example. Other examples may differ from what is described with regard to Fig. 11.

Fig. 12 is a diagram illustrating an example 1200 of selecting a CPE in a shared COT, in accordance with the present disclosure. Example 1200 shows a UE 1210 (e.g., UE 120, UE1) and another UE 1220 (e.g., UE 120, UE2) that may transmit communications over a sidelink. Example 1200 shows UE 1220 initiating a COT.

As shown by reference number 1225, UE 1220 may transmit COT-SI for a shared COT. The COT-SI may indicate when the shared COT starts, a duration of the shared COT, and an offset for the shared COT. The offset may be a point for the shared COT (e.g., start of a specified slot) at which UE 1210 can access the shared COT. UE 1220 may perform a Type 1 access to initiate the COT.

As shown by reference number 1230, the UE 1210, as a responding UE, may select the first CPE (that protects sidelink communications in the shared COT) based at least in part on detection of a transmission or reservation, based at least in part on the default CPE not reducing the gap to the size that protects sidelink transmissions in the shared COT, and based at least in part on detection of a terminated transmission by UE 1220 in a previous slot.

As shown by reference number 1235, UE 1210 may attempt transmission with the first CPE. This may include performing a Type 2 access and transmitting a communication based at least in part on the result of the Type 2 access. Attempting transmission may include transmitting the CPE at a starting position for the CPE in the gap, before a start of the current slot.

As indicated above, Fig. 12 is provided as an example. Other examples may differ from what is described with regard to Fig. 12.

Fig. 13 is a diagram illustrating an example 1300 of selecting a CPE in a shared COT, in accordance with the present disclosure.

In some aspects, a UE may select the first CPE further based at least in part on detection of a resource reservation that has a larger priority value than a priority of the intended PSCCH/PSSCH transmission. Example 1300 shows that the transmission priority for UE0 is p0, the transmission priority for UE2 is p2, and UE0 detects that UE2 has a reservation in slot n +2. When UE0 has a higher priority (lower priority value) than UE2 (e.g., p0 < p2) , UE0 may select the first CPE 1304 that makes the gap smaller than or equal to 16 μs based at least in part on a priority of the communication in the current slot and the one or more RB sets being no less than a priority of a communication scheduled or reserved by another UE in the current slot and the one or more RB sets. When UE0 has an equal or lower priority (higher priority value) than UE2 (e.g., p0 ≥ p2) , UE0 may select a default CPE based at least in part on a priority of the communication in the current slot and the one or more RB sets being no larger than a priority of a communication scheduled or reserved by another UE in the current slot and the one or more RB sets. By avoiding a low priority UE to block a high priority UE, the channel access probability may increase for high priority in-COT transmission. Example 1302 shows that when UE2 is in a shared COT initiated by UEX, the same rule may also apply for UE2. In some aspects, UE2 may have a lower priority than the reservation from UE0 and thus the UE2 may select a default CPE.

As indicated above, Fig. 13 is provided as an example. Other examples may differ from what is described with regard to Fig. 13.

Fig. 14 is a diagram illustrating examples 1400 and 1402 of selecting a CPE in a shared COT, in accordance with the present disclosure.

Example 1400 and example 1402 show candidate CPEs with different priorities. The UE may select the first CPE that reduces the gap to a size that protects sidelink transmissions in a shared COT further based at least in part on the first CPE belonging to a set of CPEs preconfigured for a priority of the communication in the current slot and the one or more RB sets. In some aspects, as shown in example 1400, UE0’s transmission in a current slot (e.g., slot n + 2) may be associated with p0, and the set of CPEs preconfigured for p0 may be {T_sym1 + 16 μs, T_sym1 + 25 μs} , where T_sym1 is the starting position of the first symbol just before the next AGC symbol and the CPE starting from T_sym1 + 16 μs can reduce the gap to a size (e.g., 16 μs) that protects sidelink transmissions in a shared COT. Therefore, UE0 may select the CPE starting from T_sym1 + 16 μs for the intended transmission in the current slot (e.g., slot n + 2) . In some aspects, as shown in example 1402, UE2’s transmission in the current slot (e.g., slot n +2) may be associated with p2, and the set of CPEs preconfigured for p2 is {T_sym1 + 34 μs, T_sym1+ 43 μs} , where the CPE that reduces the gap to a size (e.g., 16 μs) that protect sidelink transmissions in a shared COT is not included in the set of CPEs preconfigured for p2, thus UE2 may select default CPE (e.g., T_sym1 + 25 μs) based at least in part on a reservation being detected in the current slot.

As indicated above, Fig. 14 is provided as an example. Other examples may differ from what is described with regard to Fig. 14.

Fig. 15 is a diagram illustrating examples 1500 and 1502 of selecting a CPE in a shared COT, in accordance with the present disclosure.

Example 1500 shows the UE may be select the first CPE further based at least in part on a strength of the signal. The UE may transmit a communication in the current slot based at least in part on satisfying an energy detection threshold (EDT) . The UE may select the first CPE further based at least in part on a signal strength (e.g., RSRP) expected for the communication not satisfying an EDT. Not satisfying the EDT may include the signal strength being less than the EDT. By transmitting with less power, multiple UEs may share the resource. As shown in example 1500, when the measured RSRP level for the transmission in the current slot is less than the EDT, UE0 may select the CPE that reduces the gap to a size (e.g., 16 μs) that protects the sidelink transmissions in a shared COT; otherwise, UE0 may select a default CPE (e.g., T_sym1 +25 μs) based at least in part on a reservation being detected in the current slot.

As indicated above, Fig. 15 is provided as an example. Other examples may differ from what is described with regard to Fig. 15.

Fig. 16 is a diagram illustrating examples 1600 and 1602 of selecting a CPE in a shared COT, in accordance with the present disclosure.

In some aspects, if neither a resource reservation is transmitted nor resource reservations are detected for the slot and the RB sets of the intended PSCCH/PSSCH transmission, and if the UE detects that a COT initiator terminated its transmission in the previous slot, the UE may select the first CPE that protects sidelink transmissions. For example, as shown in 1600 and 1602, UE0 may receive COT-SI from UE1 that indicates an offset and duration for the shared COT, and UE0 may intend to transmit in slot starting from slot n + 2, which is the first slot after the indicated offset. If UE0 neither transmits a resource reservation nor detect a resource reservation for the current slot (e.g., slot n + 2) and UE0 detects that UE1 (COT initiator) terminated its transmission in the previous slot (e.g., slot n + 1) , UE0 may select the first CPE that reduces the gap to a size (e.g., 16 μs) that protects sidelink transmissions in a shared COT.

As indicated above, Fig. 16 is provided as an example. Other examples may differ from what is described with regard to Fig. 16.

Fig. 17 is a diagram illustrating an example 1700 of selecting a CPE based on one or more conditions, in accordance with the present disclosure. Example 1700 shows a UE 1710 (e.g., UE 120, UE1) and another UE 1720 (e.g., UE 120, UE2) that may transmit communications over a sidelink. Example 1700 shows UE 1720 initiating a COT.

In some aspects, if the first CPE that reduced the gap to protect consecutive sidelink transmissions is preconfigured for the priority associated with the intended PSCCH/PSSCH transmission, the UE may select the first UE. A fixed CPE may be selected rather than randomly selecting one from the set of multiple preconfigured CPEs for the priority associated with the intended PSCCH/PSSCH transmission,

As shown by reference number 1725, the UE 1720 may transmit COT-SI. As shown by reference number 1730, the UE 1710 may select the first CPE based at least in part on no reservation or transmission being detected for the current slot and based at least in part on detection of a transmission of an initiator UE being terminated in a previous slot. As shown by reference number 1735, the UE 1710 may attempt transmission with the CPE.

As indicated above, Fig. 17 is provided as an example. Other examples may differ from what is described with regard to Fig. 17.

Fig. 18 is a diagram illustrating examples 1800 and 1802 of selecting a CPE in a shared COT, in accordance with the present disclosure.

In some aspects, examples 1800 and 1802 show that if the first CPE that ensures the gap is reduced to the size that protects sidelink transmissions in a shared COT is preconfigured for the priority associated with the intended PSCCH/PSSCH transmission, the UE may select the first CPE. As shown in examples 1800 and 1802, UE0 intends to transmit PSCCH/PSSCH in the current slot (e.g., slot n + 2) and UE0’s PSCCH/PSSCH transmission is associated with p0. In some aspects, when the set of CPEs preconfigured for p0 is {T_sym1+16 μs, T_sym1 + 25 μs} , where T_sym1 is the starting position of the first symbol just before the next AGC symbol, UE0 may select the first CPE that reduces the gap to a size (e.g., 16 μs) that protects the sidelink transmissions in a shared COT based at least in part on the first CPE (e.g., {T_sym1+16 μs} ) , which may belong to the set of CPEs preconfigured for the priority associated with the intended transmission (s) starting from current slot (e.g., slot n + 2) . In some aspects, when the set of CPEs preconfigured for p0 is {T_sym1+52 μs, T_sym1 + 61 μs} , where T_sym1 is the starting position of the first symbol just before the next AGC symbol, the UE0 may randomly select a CPE from the set of CPEs preconfigured for the priority associated with the intended transmission (s) starting from the current slot (e.g., slot n + 2) based at least in part on the first CPE (e.g., {T_sym1 + 16 μs} ) not being included in the set of CPEs preconfigured for the priority associated with the intended transmission (s) starting from the current slot (e.g., slot n + 2) .

As indicated above, Fig. 18 is provided as an example. Other examples may differ from what is described with regard to Fig. 18.

Fig. 19 is a diagram illustrating an example process 1900 performed, in some aspects, at a UE or an apparatus of a UE, in accordance with the present disclosure. Example process 1900 is an example where the apparatus or the UE (e.g., UE 120) performs operations associated with selecting a CPE for sidelink transmissions.

As shown in Fig. 19, in some aspects, process 1900 may include selecting a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more RB sets, and based at least in part on a default CPE not being able to reduce the gap to the size (block 1910) . In some aspects, the UE (e.g., using communication manager 2106, depicted in Fig. 21) may select a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more RB sets, and based at least in part on a default CPE not being able to reduce the gap to the size, as described above.

As further shown in Fig. 19, in some aspects, process 1900 may include attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE (block 1920) . In some aspects, the UE (e.g., using communication manager 2106, depicted in Fig. 21) may attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE, as described above.

Process 1900 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.

In a first aspect, process 1900 includes receiving, from the initiator UE, COT-SI indicating an offset and a duration for the COT, where the current slot is a first slot after the offset for the UE in the COT.

In a second aspect, alone or in combination with the first aspect, selecting the first CPE includes selecting the first CPE further based at least in part on a priority of the communication in the current slot and the one or more RB sets being no less than a priority of a communication scheduled or reserved by another UE in the current slot and the one or more RB sets.

In a third aspect, alone or in combination with one or more of the first and second aspects, the first CPE is in a set of CPEs preconfigured for a priority of the communication in the current slot and the one or more RB sets.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, selecting the first CPE includes selecting the first CPE further based at least in part on a signal strength expected for the communication not satisfying an energy detection threshold.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the signal strength expected for the communication is associated with a sidelink reference signal receive power measurement.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, not satisfying the energy detection threshold includes being less than the energy detection threshold.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the size is less than or equal to 16 microseconds.

Although Fig. 19 shows example blocks of process 1900, in some aspects, process 1900 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 19. Additionally, or alternatively, two or more of the blocks of process 1900 may be performed in parallel.

Fig. 20 is a diagram illustrating an example process 2000 performed, in some aspects, at a UE or an apparatus of a UE, in accordance with the present disclosure. Example process 2000 is an example where the apparatus or the UE (e.g., UE 120) performs operations associated with selecting a CPE for sidelink transmissions.

As shown in Fig. 20, in some aspects, process 2000 may include selecting a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more RB sets (block 2010) . In some aspects, the UE (e.g., using communication manager 2106, depicted in Fig. 21) may select a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more RB sets, as described above.

As further shown in Fig. 20, in some aspects, process 2000 may include attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE (block 2020) . In some aspects, the UE (e.g., using communication manager 2106, depicted in Fig. 21) may attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE, as described above.

Process 2000 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.

In a first aspect, process 2000 includes receiving, from the initiator UE, COT-SI indicating an offset and a duration for the COT, where the current slot is a first slot after the offset for the UE in the COT.

In a second aspect, alone or in combination with the first aspect, the first CPE is in a set of CPEs preconfigured for a priority of the communication in the current slot and the one or more RB sets.

In a third aspect, alone or in combination with one or more of the first and second aspects, the size is less than or equal to 16 microseconds.

Although Fig. 20 shows example blocks of process 2000, in some aspects, process 2000 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 20. Additionally, or alternatively, two or more of the blocks of process 2000 may be performed in parallel.

Fig. 21 is a diagram of an example apparatus 2100 for wireless communication, in accordance with the present disclosure. The apparatus 2100 may be a UE, or a UE may include the apparatus 2100. In some aspects, the apparatus 2100 includes a reception component 2102, a transmission component 2104, and/or a communication manager 2106, which may be in communication with one another (in some aspects, via one or more buses and/or one or more other components) . In some aspects, the communication manager 2106 is the communication manager 140 described in connection with Fig. 1. As shown, the apparatus 2100 may communicate with another apparatus 2108, such as a UE or a network node (such as a CU, a DU, an RU, or a base station) , using the reception component 2102 and the transmission component 2104.

In some aspects, the apparatus 2100 may be configured to perform one or more operations described herein in connection with Figs. 1-18. Additionally, or alternatively, the apparatus 2100 may be configured to perform one or more processes described herein, such as process 1900 of Fig. 19, process 2000 of Fig. 20, or a combination thereof. In some aspects, the apparatus 2100 and/or one or more components shown in Fig. 21 may include one or more components of the UE described in connection with Fig. 2. Additionally, or alternatively, one or more components shown in Fig. 21 may be implemented within one or more components described in connection with Fig. 2. Additionally, or alternatively, one or more components of the set of components may be implemented at least in part as software stored in one or more memories. In some aspects, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by one or more controllers or one or more processors to perform the functions or operations of the component.

The reception component 2102 may receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus 2108. The reception component 2102 may provide received communications to one or more other components of the apparatus 2100. In some aspects, the reception component 2102 may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples) , and may provide the processed signals to the one or more other components of the apparatus 2100. In some aspects, the reception component 2102 may include one or more antennas, one or more modems, one or more demodulators, one or more MIMO detectors, one or more receive processors, one or more controllers/processors, one or more memories, or a combination thereof, of the UE described in connection with Fig. 2.

The transmission component 2104 may transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus 2108. In some aspects, one or more other components of the apparatus 2100 may generate communications and may provide the generated communications to the transmission component 2104 for transmission to the apparatus 2108. In some aspects, the transmission component 2104 may perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples) , and may transmit the processed signals to the apparatus 2108. In some aspects, the transmission component 2104 may include one or more antennas, one or more modems, one or more modulators, one or more transmit MIMO processors, one or more transmit processors, one or more controllers/processors, one or more memories, or a combination thereof, of the UE described in connection with Fig. 2. In some aspects, the transmission component 2104 may be co-located with the reception component 2102 in one or more transceivers.

The communication manager 2106 may support operations of the reception component 2102 and/or the transmission component 2104. In some aspects, the communication manager 2106 may receive information associated with configuring reception of communications by the reception component 2102 and/or transmission of communications by the transmission component 2104. Additionally, or alternatively, the communication manager 2106 may generate and/or provide control information to the reception component 2102 and/or the transmission component 2104 to control reception and/or transmission of communications.

In some aspects, the communication manager 2106 may select a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more RB sets, and based at least in part on a default CPE not being able to reduce the gap to the size. The communication manager 2106 may attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

The reception component 2102 may receive, from the initiator UE, COT-SI indicating an offset and a duration for the COT, where the current slot is a first slot after the offset for the UE in the COT.

In some aspects, the communication manager 2106 may select a first CPE that reduces a gap, between a previous slot when a transmission by an initiator UE of a COT is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more RB sets. The communication manager 2106 may attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

The number and arrangement of components shown in Fig. 21 are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in Fig. 21. Furthermore, two or more components shown in Fig. 21 may be implemented within a single component, or a single component shown in Fig. 21 may be implemented as multiple, distributed components. Additionally, or alternatively, a set of (one or more) components shown in Fig. 21 may perform one or more functions described as being performed by another set of components shown in Fig. 21.

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

Aspect 1: A method of wireless communication performed by a user equipment (UE) , comprising: selecting a first cyclic prefix extension (CPE) that reduces a gap, between a previous slot when a transmission by an initiator UE of a channel occupancy time (COT) is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more resource block (RB) sets, and based at least in part on a default CPE not being able to reduce the gap to the size; and attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

Aspect 2: The method of Aspect 1, further comprising receiving, from the initiator UE, COT sharing indication (COT-SI) indicating an offset and a duration for the COT, wherein the current slot is a first slot after the offset for the UE in the COT.

Aspect 3: The method of any of Aspects 1-2, wherein selecting the first CPE includes selecting the first CPE further based at least in part on a priority of the communication in the current slot and the one or more RB sets being no less than a priority of a communication scheduled or reserved by another UE in the current slot and the one or more RB sets.

Aspect 4: The method of any of Aspects 1-3, wherein the first CPE is in a set of CPEs preconfigured for a priority of the communication in the current slot and the one or more RB sets.

Aspect 5: The method of any of Aspects 1-4, wherein selecting the first CPE includes selecting the first CPE further based at least in part on a signal strength expected for the communication not satisfying an energy detection threshold.

Aspect 6: The method of Aspect 5, wherein the signal strength expected for the communication is associated with a sidelink reference signal receive power measurement.

Aspect 7: The method of Aspect 5, wherein not satisfying the energy detection threshold includes being less than the energy detection threshold.

Aspect 8: The method of any of Aspects 1-7, wherein the size is less than or equal to 16 microseconds.

Aspect 9: A method of wireless communication performed by a user equipment (UE) , comprising: selecting a first cyclic prefix extension (CPE) that reduces a gap, between a previous slot when a transmission by an initiator UE of a channel occupancy time (COT) is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more resource block (RB) sets; and attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.

Aspect 10: The method of Aspect 9, further comprising receiving, from the initiator UE, COT sharing indication (COT-SI) indicating an offset and a duration for the COT, wherein the current slot is a first slot after the offset for the UE in the COT.

Aspect 11: The method of any of Aspects 9-10, wherein the first CPE is in a set of CPEs preconfigured for a priority of the communication in the current slot and the one or more RB sets.

Aspect 12: The method of any of Aspects 9-11, wherein the size is less than or equal to 16 microseconds.

Aspect 13: An apparatus for wireless communication at a device, the apparatus comprising one or more processors; one or more memories coupled with the one or more processors; and instructions stored in the one or more memories and executable by the one or more processors to cause the apparatus to perform the method of one or more of Aspects 1-12.

Aspect 14: An apparatus for wireless communication at a device, the apparatus comprising one or more memories and one or more processors coupled to the one or more memories, the one or more processors configured to cause the device to perform the method of one or more of Aspects 1-12.

Aspect 15: An apparatus for wireless communication, the apparatus comprising at least one means for performing the method of one or more of Aspects 1-12.

Aspect 16: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by one or more processors to perform the method of one or more of Aspects 1-12.

Aspect 17: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more of Aspects 1-12.

Aspect 18: A device for wireless communication, the device comprising a processing system that includes one or more processors and one or more memories coupled with the one or more processors, the processing system configured to cause the device to perform the method of one or more of Aspects 1-12.

Aspect 19: An apparatus for wireless communication at a device, the apparatus comprising one or more memories and one or more processors coupled to the one or more memories, the one or more processors individually or collectively configured to cause the device to perform the method of one or more of Aspects 1-12.

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

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

The hardware and data processing apparatus used to implement the various illustrative logics, logical blocks, modules and circuits described in connection with the aspects disclosed herein may be implemented or performed with a general purpose single-or multi-chip processor, a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. A processor also may be implemented as a combination of computing devices, in some aspects, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. In some aspects, particular processes and methods may be performed by circuitry that is specific to a given function.

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

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

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items and may be used interchangeably with “one or more. ” Further, as used herein, the article “the” is intended to include one or more items referenced in connection with the article “the” and may be used interchangeably with “the one or more. ” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items and may be used interchangeably with “one or more. ” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used herein, the terms “has, ” “have, ” “having, ” or the like are intended to be open-ended terms that do not limit an element that they modify (e.g., an element “having” A may also have B) . Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. Also, as used herein, the term “or” is intended to be inclusive when used in a series and may be used interchangeably with “and/or, ” unless explicitly stated otherwise (e.g., if used in combination with “either” or “only one of” ) .

Claims

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

one or more memories; and

one or more processors, coupled to the one or more memories, individually or collectively, configured to:

select a first cyclic prefix extension (CPE) that reduces a gap, between a previous slot when a transmission by an initiator UE of a channel occupancy time (COT) is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more resource block (RB) sets, and based at least in part on a default CPE not being able to reduce the gap to the size; and

attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.
The apparatus of claim 1, wherein the one or more processors are individually or collectively configured to receive, from the initiator UE, COT sharing indication (COT-SI) indicating an offset and a duration for the COT, wherein the current slot is a first slot after the offset for the UE in the COT.
The apparatus of claim 1, wherein the one or more processors, to select the CPE, are individually or collectively configured to select the CPE further based at least in part on a priority of the communication in the current slot and the one or more RB sets being no less than a priority of a communication scheduled or reserved by another UE in the current slot and the one or more RB sets.
The apparatus of claim 1, wherein the first CPE is in a set of CPEs preconfigured for a priority of the communication in the current slot and the one or more RB sets.
The apparatus of claim 1, wherein the one or more processors, to select the CPE, are individually or collectively configured to select the CPE further based at least in part on a signal strength expected for the communication not satisfying an energy detection threshold.
The apparatus of claim 5, wherein the signal strength expected for the communication is associated with a sidelink reference signal receive power measurement.
The apparatus of claim 5, wherein not satisfying the energy detection threshold includes being less than the energy detection threshold.
The apparatus of claim 1, wherein the size is less than or equal to 16 microseconds.
An apparatus for wireless communication at a user equipment (UE) , comprising:

one or more memories; and

one or more processors, coupled to the one or more memories, individually or collectively configured to:

select a first cyclic prefix extension (CPE) that reduces a gap, between a previous slot when a transmission by an initiator UE of a channel occupancy time (COT) is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more resource block (RB) sets; and

attempt transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.
The apparatus of claim 9, wherein the one or more processors are individually or collectively configured to receive, from the initiator UE, COT sharing indication (COT-SI) indicating an offset and a duration for the COT, wherein the current slot is a first slot after the offset for the UE in the COT.
The apparatus of claim 9, wherein the first CPE is in a set of CPEs preconfigured for a priority of the communication in the current slot and the one or more RB sets.
The apparatus of claim 9, wherein the size is less than or equal to 16 microseconds.
A method of wireless communication performed by a user equipment (UE) , comprising:

selecting a first cyclic prefix extension (CPE) that reduces a gap, between a previous slot when a transmission by an initiator UE of a channel occupancy time (COT) is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on transmission or detection of a reservation for the current slot and one or more resource block (RB) sets, and based at least in part on a default CPE not being able to reduce the gap to the size; and

attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.
The method of claim 13, further comprising receiving, from the initiator UE, COT sharing indication (COT-SI) indicating an offset and a duration for the COT, wherein the current slot is a first slot after the offset for the UE in the COT.
The method of claim 13, wherein selecting the first CPE includes selecting the first CPE further based at least in part on a priority of the communication in the current slot and the one or more RB sets being no less than a priority of a communication scheduled or reserved by another UE in the current slot and the one or more RB sets.
The method of claim 13, wherein the first CPE is in a set of CPEs preconfigured for a priority of the communication in the current slot and the one or more RB sets.
The method of claim 13, wherein selecting the first CPE includes selecting the first CPE further based at least in part on a signal strength expected for the communication not satisfying an energy detection threshold.
The method of claim 17, wherein the signal strength expected for the communication is associated with a sidelink reference signal receive power measurement.
The method of claim 17, wherein not satisfying the energy detection threshold includes being less than the energy detection threshold.
The method of claim 13, wherein the size is less than or equal to 16 microseconds.
A method of wireless communication performed by a user equipment (UE) , comprising:

selecting a first cyclic prefix extension (CPE) that reduces a gap, between a previous slot when a transmission by an initiator UE of a channel occupancy time (COT) is terminated and a current slot, to a size that protects sidelink transmissions in a shared COT, based at least in part on no reservation being transmitted or detected for the current slot and one or more resource block (RB) sets; and

attempting transmission of a communication in the one or more RB sets starting from the current slot with the first CPE.
The method of claim 21, further comprising receiving, from the initiator UE, COT sharing indication (COT-SI) indicating an offset and a duration for the COT, wherein the current slot is a first slot after the offset for the UE in the COT.
The method of claim 21, wherein the first CPE is in a set of CPEs preconfigured for a priority of the communication in the current slot and the one or more RB sets.
The method of claim 21, wherein the size is less than or equal to 16 microseconds.