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EP-4209088-B1 - FREQUENCY RESOURCE RESERVATION FOR SIDELINK COMMUNICATION

EP4209088B1EP 4209088 B1EP4209088 B1EP 4209088B1EP-4209088-B1

Inventors

  • XUE, YISHENG
  • LIU, CHIH-HAO
  • SUN, JING
  • ZHANG, XIAOXIA

Dates

Publication Date
20260506
Application Date
20210708

Claims (15)

  1. A method of wireless communication performed by a first user equipment, UE, the method comprising: sensing (1410) in a sidelink resource pool within a shared radio frequency band; reserving (1420), based on the sensing, a frequency resource of the sidelink resource pool within an instance of a variable time range; transmitting a soft reservation for a second frequency resource of the sidelink resource pool within a second instance of the variable time range; performing (1430), in the shared radio frequency band, one or more listen-before-talks, LBTs,; and transmitting (1440), to a second UE based on the one or more LBTs, a sidelink transmission using the frequency resource within the instance of the variable time range.
  2. The method of claim 1, wherein the instance of the variable time range spans one or more contiguous slots.
  3. The method of claim 1, wherein the frequency resource is in a same subchannel of the sidelink resource pool over the instance of the variable time range.
  4. The method of claim 3, wherein the reserving comprises: transmitting a reservation including at least one of a subchannel index identifying the frequency resource or a slot index identifying a beginning slot of the instance of the variable time range.
  5. The method of claim 1, further comprising: determining the variable time range based on a predetermined value.
  6. The method of claim 1, further comprising: receiving an indication of the variable time range in at least one of a radio resource control, RRC, configuration or a system information block, SIB,.
  7. The method of claim 1, further comprising: determining the variable time range based on at least one of a packet delay budget, PDB, or a traffic priority associated with the sidelink transmission.
  8. The method of claim 1, wherein: the performing the one or more LBTs comprises: performing, in the shared radio frequency band, a first LBT based on a first slot boundary in the instance of the variable time range; and performing, responsive to identifying a failure of the first LBT, a second LBT based on a second slot boundary after the first slot boundary; and the transmitting comprises, responsive to identifying a success of the second LBT, beginning transmission of the sidelink transmission from the second slot boundary in the instance of the variable time range.
  9. The method of claim 8, wherein: the performing the first LBT comprises: performing a countdown until the first slot boundary; and the performing the second LBT comprises: resuming the countdown.
  10. The method of claim 1, wherein the transmitting the soft reservation comprises: transmitting the sidelink transmission including a first transport block, wherein the soft reservation is associated with a second transport block different from the first transport block.
  11. The method of claim 10, further comprising at least one of: transmitting, to a third UE in response to determining the soft reservation is not preempted, a second sidelink transmission including the second transport block using the second frequency resource within the second instance of the variable time range; or refraining from transmitting, in response to determining the soft reservation is preempted, the second sidelink transmission including the second transport block using the second frequency resource within the second instance of the variable time range.
  12. The method of claim 1, further comprising: identifying, based on the sensing, candidate resources in the sidelink resource pool within a resource selection window; receiving, from a third UE, a soft reservation for a second frequency resource of the sidelink resource pool within a second instance of the variable time range, the soft reservation associated with one or more of the candidate resources; determining, based on the soft reservation, the one or more of the candidate resources as unavailable; and selecting, based on a number of remaining candidate resources, the frequency resource from the candidate resources, wherein the selecting comprises at least one of: selecting, based on determining the number of remaining candidate resources in the resource selection window satisfies a threshold, the frequency resource within the instance of the variable time range from the remaining candidate resources; or selecting, based on determining the number of remaining candidate resources in the resource selection window fails to satisfy the threshold, the frequency resource from a subset of the candidate resources including at least a first candidate resource of the one or more of the candidate resources.
  13. A first user equipment, UE, comprising: means for sensing in a sidelink resource pool within a shared radio frequency band; means for reserving, based on the sensing, a frequency resource of the sidelink resource pool within an instance of a variable time range; means for transmitting a soft reservation for a second frequency resource of the sidelink resource pool within a second instance of the variable time range; means for performing, in the shared radio frequency band, one or more listen-before-talks, LBTs,; and means for transmitting, to a second UE based on the one or more LBTs, a sidelink transmission using the frequency resource within the instance of the variable time range.
  14. The first user equipment, UE, of claim 13 comprising means for undertaking the method of any of claims 2 to 12.
  15. A non-transitory computer-readable medium having program code recorded thereon, the program code comprising code which when executed on a user equipment undertakes the method of any of claims 1 to 12.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS The present application claims priority to and the benefit of U.S. Patent Application No. 17/305,455, filed July 7, 2021, and of U.S. Provisional Application No. 62/706,688, filed September 2, 2020. TECHNICAL FIELD This application relates to wireless communication systems, and more particularly to frequency resource reservation for sidelink communication over a shared radio frequency band. US 2020/0029340 describes various arrangements for cycling communication and identifying a resource selection window. INTRODUCTION Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). A wireless multiple-access communications system may include a number of base stations (BSs), each simultaneously supporting communications for multiple communication devices, which may be otherwise known as user equipment (UE). To meet the growing demands for expanded mobile broadband connectivity, wireless communication technologies are advancing from the long term evolution (LTE) technology to a next generation new radio (NR) technology, which may be referred to as 5th Generation (5G). For example, NR is designed to provide a lower latency, a higher bandwidth or a higher throughput, and a higher reliability than LTE. NR is designed to operate over a wide array of spectrum bands, for example, from low-frequency bands below about 1 gigahertz (GHz) and mid-frequency bands from about 1 GHz to about 6 GHz, to high-frequency bands such as millimeter wave (mmWave) bands. NR is also designed to operate across different spectrum types, from licensed spectrum to unlicensed and shared spectrum. Spectrum sharing enables operators to opportunistically aggregate spectrums to dynamically support high-bandwidth services. Spectrum sharing can extend the benefit of NR technologies to operating entities that may not have access to a licensed spectrum. In a wireless communication network, a BS may communicate with a UE in an uplink direction and a downlink direction. Sidelink was introduced in LTE to allow a UE to send data to another UE without tunneling through the BS and/or an associated core network. The LTE sidelink technology had been extended to provision for device-to-device (D2D) communications, vehicle-to-everything (V2X) communications, and/or cellular vehicle-to-everything (C-V2X) communications. Similarly, NR may be extended to support sidelink communications, D2D communications, V2X communications, and/or C-V2X over licensed bands and/or unlicensed bands. BRIEF SUMMARY OF SOME EXAMPLES The following summarizes some aspects of the present disclosure to provide a basic understanding of the discussed technology. This summary is not an extensive overview of all contemplated features of the disclosure and is intended neither to identify key or critical elements of all aspects of the disclosure nor to delineate the scope of any or all aspects of the disclosure. Its sole purpose is to present some concepts of one or more aspects of the disclosure in summary form as a prelude to the more detailed description that is presented later. The invention as defined in the independent claims to which reference is directed with preferred feature set out in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a wireless communication network according to some aspects of the present disclosure.FIG. 2 illustrates a wireless communication network that provisions for sidelink communications according to some aspects of the present disclosure.FIG. 3A is a sequence diagram illustrating an autonomous sidelink sensing method according to some aspects of the present disclosure.FIG. 3B illustrates an autonomous sidelink sensing scheme according to some aspects of the present disclosure.FIG. 4A is a sequence diagram illustrating an autonomous sidelink sensing method according to some aspects of the present disclosure.FIG. 4B illustrates an autonomous sidelink sensing scheme according to some aspects of the present disclosure.FIG. 5 illustrates a sidelink communication scheme according to some aspects of the present disclosure.FIG. 6A is a flow diagram illustrating a method for last-minute re-evaluation and performance of a listen-before-talk (LBT) with respect to a reserved frequency resource according to some aspects of the present disclosure.FIG. 6B illustrates last-minute re-evaluation with respect to a reserved frequency resource according to some aspects of the present disclosure.FIG. 7A is a flow diagram of a method for performing an LBT with respect to a group of back-to-back slots in a reserved frequency resource according to some aspects of the present disclosure.FIG. 7B is a timing diagram of one or more LBTs being performed with respe