# US 12,004,213 B2 · Method and apparatus for adjusting contention window in wireless communication system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,004,213 B2 - Document ID: US12004213B2 - Status: Granted - Kind: B2 - Application number: 16/799,309 - Filed: 2020-02-24 - Published: 2020-08-27 - Granted: 2024-06-04 - Earliest claimed: 2019-02-22 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Jinyoung Oh; Jeongho Yeo; Hyunseok Ryu; Sungjin Park; Jonghyun Bang; Cheolkyu Shin - Web page: https://patentgrep.com/patent/US12004213B2 ## CPC - H04W 74/08: Non-scheduled access, e.g. ALOHA (hybrid access H04W74/02) - H04W 74/0825: {with collision detection} - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract The disclosure relates to a communication method and system for converging a 5G communication system for supporting higher data rates beyond a 4G system with a technology for IoT. The disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. A method of operating a BS includes monitoring a channel for a plurality of subbands, based on a first contention window configured in each of the plurality of subbands; transmitting a downlink signal to a terminal, based on a result of the monitoring; obtaining, from the terminal, a transmission result of the downlink signal for a reference duration; and determining a second contention window for monitoring a next channel for the plurality of subbands, based on the obtained transmission result. ## Claims ### Claim 1 A method for multiple sub-bands access by a base station (BS) in a wireless communication system, the method comprising: identifying at least one hybrid automatic repeat request-acknowledgement (HARQ-ACK) feedback corresponding to at least one physical downlink shared channel (PDSCH) in a reference duration for a downlink channel occupancy, wherein the at least one PDSCH in the reference duration includes a PDSCH that partially but not fully overlaps with a sub-band among multiple sub-bands; determining a contention window for the sub-band among the multiple sub-bands, based on the at least one HARQ-ACK feedback including a HARQ-ACK feedback corresponding to the PDSCH that partially but not fully overlaps with the sub-band among the multiple sub-bands; identifying a number within the contention window for the sub-band; sensing the sub-band based on the number and a defer duration; and performing a downlink transmission on the sub-band, in case that the sub-band is sensed to be idle, wherein the reference duration includes a first slot corresponding to transmission of the at least one PDSCH within the downlink channel occupancy. ### Claim 2 (depends on 1) The method of claim 1, wherein the PDSCH that partially but not fully overlaps with the sub-band is transmitted across the multiple sub-bands, and wherein the at least one PDSCH further includes a PDSCH that fully overlaps with the sub-band among the multiple sub-bands. ### Claim 3 (depends on 1) The method of claim 1, wherein an initial value of the contention window for the sub-band is identified as a minimum value. ### Claim 4 (depends on 1) The method of claim 1, wherein the downlink channel occupancy is a latest downlink channel occupancy. ### Claim 5 (depends on 1) The method of claim 1, wherein the reference duration depends on a subcarrier spacing. ### Claim 6 (depends on 1) The method of claim 1, in case that the at least one HARQ-ACK feedback is a code block group based feedback for the at least one PDSCH, the contention window is adjusted based on a ratio of ACK or NACK for code block groups of the at least one PDSCH. ### Claim 7 (depends on 1) The method of claim 1, wherein the multiple sub-bands are within a bandwidth of a carrier. ### Claim 8 (depends on 1) The method of claim 1, wherein the reference duration is defined as a duration from a beginning of the downlink channel occupancy until an end of the first slot corresponding to transmission of the at least one PDSCH. ### Claim 9 A method for multiple sub-bands access by a terminal in a wireless communication system, the method comprising: transmitting, to a base station (BS), at least one hybrid automatic repeat request-acknowledgement (HARQ-ACK) feedback corresponding to at least one physical downlink shared channel (PDSCH) in a reference duration for a downlink channel occupancy, wherein the at least one PDSCH in the reference duration includes a PDSCH that partially but not fully overlaps with a sub-band among multiple sub-bands; and receiving, from the BS, a downlink signal on the sub-band, in case that the sub-band is idle, wherein the at least one HARQ-ACK feedback including a HARQ-ACK feedback corresponding to the PDSCH that partially but not fully overlaps with the sub-band among the multiple sub-bands is used for determination of a contention window for the sub-band among the multiple sub-bands, wherein whether the sub-band is idle is based on a defer duration and a number identified within the contention window for the sub-band, and wherein the reference duration includes a first slot corresponding to transmission of the at least one PDSCH within the downlink channel occupancy. ### Claim 10 (depends on 9) The method of claim 9, wherein the PDSCH that partially but not fully overlaps with the sub-band is received across the multiple sub-bands, and wherein the at least one PDSCH further includes a PDSCH that fully overlaps with the sub-band among the multiple sub-bands. ### Claim 11 (depends on 9) The method of claim 9, wherein an initial value of the contention window for the sub-band is identified as a minimum value. ### Claim 12 (depends on 9) The method of claim 9, wherein the downlink channel occupancy is a latest downlink channel occupancy. ### Claim 13 A base station (BS), comprising: a transceiver; and a controller configured to: identify at least one hybrid automatic repeat request-acknowledgement (HARQ-ACK) feedback corresponding to at least one physical downlink shared channel (PDSCH) in a reference duration for a downlink channel occupancy, wherein the at least one PDSCH in the reference duration includes a PDSCH that partially but not fully overlaps with a sub-band among multiple sub-bands, determine a contention window for the sub-band among the multiple sub-bands based on the at least one HARQ-ACK feedback including a HARQ-ACK feedback corresponding to the PDSCH that partially but not fully overlaps with the sub-band among the multiple sub-bands, identify a number within the contention window for the sub-band, sense the sub-band based on the number and a defer duration, and perform a downlink transmission on the sub-band, in case that the sub-band is sensed to be idle, wherein the reference duration includes a first slot corresponding to transmission of the at least one PDSCH within the downlink channel occupancy. ### Claim 14 (depends on 13) The BS of claim 13, wherein the PDSCH that partially but not fully overlaps with the sub-band is transmitted across the multiple sub-bands, and wherein the at least one PDSCH further includes a PDSCH that fully overlaps with the sub-band among the multiple sub-bands. ### Claim 15 (depends on 13) The BS of claim 13, wherein an initial value of the contention window for the sub-band is identified as a minimum value. ### Claim 16 (depends on 13) The BS of claim 13, wherein the downlink channel occupancy is a latest downlink channel occupancy. ### Claim 17 A terminal, comprising: a transceiver; and a controller configured to: transmit, to a base station (BS), at least one hybrid automatic repeat request-acknowledgement (HARQ-ACK) feedback corresponding to at least one physical downlink shared channel (PDSCH) in a reference duration for a downlink channel occupancy wherein the at least one PDSCH in the reference duration includes a PDSCH that partially but not fully overlaps with a sub-band among multiple sub-bands, and receive, from the BS, a downlink signal on the sub-band, in case that the sub-band is idle, wherein the at least one HARQ-ACK feedback including a HARQ-ACK feedback corresponding to the PDSCH that partially but not fully overlaps with the sub-band among the multiple sub-bands is used for determination of a contention window for the sub-band among the multiple sub-bands, wherein whether the sub-band is idle is based on a defer duration and a number identified within the contention window for the sub-band, and wherein the reference duration includes a first slot corresponding to transmission of the at least one PDSCH within the downlink channel occupancy. ### Claim 18 (depends on 17) The terminal of claim 17, wherein the PDSCH that partially but not fully overlaps with the sub-band is received across the multiple sub-bands, and wherein the at least one PDSCH further includes a PDSCH that fully overlaps with the sub-band among the multiple sub-bands. ### Claim 19 (depends on 17) The terminal of claim 17, wherein an initial value of the contention window for the sub-band is identified as a minimum value. ### Claim 20 (depends on 17) The terminal of claim 17, wherein the downlink channel occupancy is a latest downlink channel occupancy.