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EP-4736565-A1 - ACCESS BEFORE AN OFFSET IN A SHARED CHANNEL OCCUPANCY TIME

EP4736565A1EP 4736565 A1EP4736565 A1EP 4736565A1EP-4736565-A1

Abstract

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first user equipment (UE) may receive information for a shared channel occupancy time (COT) of a second UE that indicates an offset in the COT before which the first UE is not able to perform listen-before-talk (LBT) to access the shared COT and after which the first UE is able to perform LBT to access the shared COT. The UE may transmit, to the second UE, sidelink control information that indicates a reserved slot that is reserved for the first UE in the shared COT before the offset. The UE may perform an LBT procedure to perform a transmission at the reserved slot within the shared COT. Numerous other aspects are described.

Inventors

  • CHISCI, GIOVANNI
  • LIU, CHIH-HAO
  • SUN, JING
  • ZHANG, XIAOXIA
  • STEFANATOS, Stelios

Assignees

  • QUALCOMM Incorporated

Dates

Publication Date
20260506
Application Date
20240508

Claims (20)

  1. 1. A first user equipment (UE) for wireless communication, 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 first UE to: receive information for a shared channel occupancy time (COT) of a second UE that indicates an offset in the COT before which the first UE is not able to perform listen-before-talk (LBT) to access the shared COT and after which the first UE is able to perform LBT to access the shared COT; transmit, to the second UE, sidelink control information that indicates a reserved slot that is reserved for the first UE in the shared COT before the offset; and perform an LBT procedure to perform a transmission at the reserved slot within the shared COT.
  2. 2. The first UE of claim 1, wherein the one or more processors are individually or collectively configured to cause the first UE to transmit a communication based at least in part on a result of the LBT procedure.
  3. 3. The first UE of claim 1, wherein the one or more processors, to perform the LBT procedure, are individually or collectively configured to cause the first UE to perform the LBT procedure within a specified time window that starts before the reserved slot.
  4. 4. The first UE of claim 3, wherein the LBT procedure includes a type 2A LBT procedure, a type 2B LBT procedure, or a type 2C LBT procedure.
  5. 5. The first UE of claim 1, wherein the transmission from the first UE in the reserved slot is associated with a cyclic prefix extension (CPE) at a starting position that is later than a starting position used by the second UE for a communication in the shared COT.
  6. 6. The first UE of claim 1, wherein the transmission is not associated with a cyclic prefix extension (CPE).
  7. 7. A second user equipment (UE) for wireless communication, 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 second UE to: transmit, to a first UE, information for a shared channel occupancy time (COT) of the second UE that indicates an offset in the shared COT before which the first UE is not able to perform listen-before-talk (LBT) to access the shared COT and after which the first UE is able to perform LBT to access the shared COT; receive sidelink control information (SCI) that indicates a reserved slot that is reserved for the first UE in the shared COT before the offset; drop a communication by the second UE within the shared COT before the offset based at least in part on the reserved slot; and attempt to resume transmission of the communication by the second UE before the offset.
  8. 8. The second UE of claim 7, wherein the one or more processors, to attempt to resume transmission, individually or collectively configured to cause the second UE to attempt to resume transmission based at least in part on a determination that the reserved slot for the first UE is a cause of the dropping.
  9. 9. The second UE of claim 8, wherein the one or more processors, to attempt to resume transmission, are individually or collectively configured to cause the second UE to attempt to resume transmission further based at least in part on a time gap, from an end of the reserved slot, being smaller than a gap threshold.
  10. 10. The second UE of claim 8, wherein the one or more processors, to attempt to resume transmission, are individually or collectively configured to cause the second UE to attempt to resume transmission further based at least in part on a time gap between two consecutive slots being smaller than a threshold time duration, and wherein the two consecutive slots are for the communication by the second UE and a communication by the first UE.
  11. 11. The second UE of claim 8, wherein the determination is based at least in part on one or more matching identifiers (IDs).
  12. 12. The second UE of claim 11, wherein a first ID of the one or more matching IDs is included in the SCI.
  13. 13. The second UE of claim 12, wherein a second ID of the one or more matching IDs is included in the information for the shared COT.
  14. 14. The second UE of claim 11, wherein the one or more matching IDs include a pair of source and destination IDs for unicast.
  15. 15. The second UE of claim 11, wherein a first ID of the one or more matching IDs includes a destination ID for groupcast.
  16. 16. The second UE of claim 11, wherein a first ID of the one or more matching IDs includes a destination ID for broadcast.
  17. 17. The second UE of claim 7, wherein the one or more processors, to attempt to resume transmission, are individually or collectively configured to cause the second UE to attempt to resume transmission based at least in part on a detection of a communication from the first UE.
  18. 18. The second UE of claim 17, wherein the communication from the first UE is associated with the reserved slot.
  19. 19. The second UE of claim 17, wherein the one or more processors, to attempt to resume transmission, are individually or collectively configured to cause the second UE to attempt to resume transmission further based at least in part on a time gap, from an end of the communication from the first UE that is detected, being smaller than a gap threshold.
  20. 20. The second UE of claim 17, wherein the one or more processors, to attempt to resume transmission, are individually or collectively configured to cause the second UE to attempt to resume transmission further based at least in part on a time gap between two consecutive slots being smaller than a gap threshold, and wherein the two consecutive slots are for the communication by the second UE and a communication by the first UE.

Description

ACCESS BEFORE AN OFFSET IN A SHARED CHANNEL OCCUPANCY TIME CROSS-REFERENCE TO RELATED APPLICATION [0001] This Patent Application claims priority to Greece Patent Application No. 20230100536, filed on June 30, 2023, entitled “ACCESS BEFORE AN OFFSET IN A SHARED CHANNEL OCCUPANCY TIME,” and assigned to the assignee hereof. The disclosure of the prior Application is considered part of and is incorporated by reference into this Patent Application. FIELD OF THE DISCLOSURE [0002] Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for access before an offset in a shared channel occupancy time. BACKGROUND [0003] 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 (3 GPP). [0004] 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). [0005] 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 [0006] A user equipment (UE) 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 for a channel occupancy time (COT). If UE1 does not need to use the whole COT for a sidelink transmission or reception, UE1 may share the COT with another UE, such as with a second UE (UE2). UE1 may indicate resource blocks (RBs) and a time duration for the COT. UE1 may be a COT initiator that performs a channel access procedure (e.g., a listen-before-talk (LBT) procedure) and starts the COT. UE1 may transmit data to UE2 in a sidelink communication during the shared COT. UE2 may be a COT responder and may provide a feedback communication to UE1, in response to the sidelink communication, during the shared COT. UE2 may perform a type 2 LBT procedure. However, if UE2 can attempt to access the channel with LBT Type 2 and transmit anywhere in the COT (after decoding COT sharing information (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. If UE1 cannot transmit in its own COT, UEl’s communications will degrade and latency will increase. [0007] UE1 may share the COT and indicate 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. If UE2 has reserved slots that fall within the shared COT, UE2 cannot access these reserved slo