# US 11,121,977 B2 · Contention window size adjustment in a 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 11,121,977 B2 - Document ID: US11121977B2 - Status: Granted - Kind: B2 - Application number: 16/597,708 - Filed: 2019-10-09 - Published: 2020-02-06 - Granted: 2021-09-14 - Earliest claimed: 2019-10-09 - Assignees: Lenovo Innovations Limited (Hong Kong) - Applicants: Lenovo Innovations Limited (Hong Kong) - Inventors: Haipeng Lei; Zukang Shen; Xiaodong Yu - Web page: https://patentgrep.com/patent/US11121977B2 ## CPC - H04L 47/27: Evaluation or update of window size, e.g. using information derived from acknowledged [ACK] packets - H04L 1/00: Arrangements for detecting or preventing errors in the information received {(correcting synchronisation H04L7/00)} - H04L 1/0026: {Transmission of channel quality indication} - H04L 1/1812: Hybrid protocols; Hybrid automatic repeat request [HARQ] - H04L 1/1887: {Scheduling and prioritising arrangements} - H04L 5/0055: {Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861)} - H04L 5/0057: {Physical resource allocation for CQI} - H04L 5/006: {Quality of the received signal, e.g. BER, SNR, water filling} - H04L 5/0078: {Timing of allocation} - H04W 40/16: based on interference - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Apparatuses, methods, and systems are disclosed for contention window size adjustment. One apparatus includes a transmitter that transmits data on a carrier to a set of devices in a first transmission burst having a duration of at least one subframe. In some embodiments, the set of devices includes one or more devices. In various embodiments, the apparatus includes a receiver that receives feedback information from each device. In certain embodiments, the apparatus includes a processor that determines, based on the feedback information, whether interference above a predetermined level exists on the carrier during the first transmission burst at each device, adjusts a contention window size based on the determination of whether interference above the predetermined level exists on the carrier during the first transmission burst at each device, and determines a value N between a predetermined minimum contention window size and the adjusted contention window size. ## Claims ### Claim 1 An apparatus comprising a user equipment, the apparatus further comprising: a receiver that receives data on a set of data channels, wherein the set of data channels comprises one or more data channels in a transmission burst on a carrier; a processor that determines an indication of an interference level, wherein the indication indicates whether interference above a predetermined level exists on the carrier during the transmission burst based on a received signal-to-interference-plus-noise ratio of each data channel of the set of data channels, and the indication comprises an explicit indication of the presence of another device sharing the carrier; and a transmitter that transmits the indication to a base unit, wherein the interference level is determinable using the indication. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the processor determines that interference above the predetermined level exists on the carrier during the transmission burst if a percentage of data channels of the set of data channels with the received signal-to-interference-plus-noise ratio of the data channel results in a block error ratio higher than a target block error ratio by a margin percentage that is greater than a threshold percentage. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the processor determines that interference above the predetermined level exists on the carrier during the transmission burst if the set of data channels comprises only one data channel and the received signal-to-interference-plus-noise ratio of the data channel results in a block error ratio higher than a target block error ratio by a margin percentage. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the processor determines that interference above the predetermined level exists on the carrier during the transmission burst if a percentage of data channels of the set of data channels with the received signal-to-interference-plus-noise ratio of the data channel results in a first modulation and coding scheme lower than a second modulation and coding scheme by a margin level that is greater than a threshold percentage. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the first modulation and coding scheme is determined for achieving a target block error ratio based on the received signal-to-interference-plus-noise ratio of the data channel. ### Claim 6 (depends on 4) The apparatus of claim 4, wherein the second modulation and coding scheme is indicated in downlink control information scheduling the data channel. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the processor determines that interference above the predetermined level exists on the carrier during the transmission burst if the set of data channels comprises only one data channel and the received signal-to-interference-plus-noise ratio of the data channel results in a first modulation and coding scheme lower than a second modulation and coding scheme by a margin level. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein the first modulation and coding scheme is determined for achieving a target block error ratio based on the received signal-to-interference-plus-noise ratio of the data channel and the second modulation and coding scheme is indicated in downlink control information scheduling the data channel. ### Claim 9 A method comprising: receiving, at a user equipment, data on a set of data channels, wherein the set of data channels comprises one or more data channels in a transmission burst on a carrier; determining an indication of an interference level, wherein the indication indicates whether interference above a predetermined level exists on the carrier during the transmission burst based on a received signal-to-interference-plus-noise ratio of each data channel of the set of data channels, and the indication comprises an explicit indication of the presence of another device sharing the carrier; and transmitting the indication to a base unit, wherein the interference level is determinable using the indication. ### Claim 10 An apparatus comprising: a transmitter that transmits data in a first transmission burst on a carrier to a set of devices, wherein the set of devices comprises one or more devices; a receiver that receives feedback information from each device of the set of devices, wherein the feedback information indicates whether interference above a predetermined level exists on the carrier during the transmission burst, and the feedback information is determined by each device of the set of devices based on a received signal-to-interference-plus-noise ratio of each device of the set of devices during the transmission burst; and a processor that adjusts a contention window size based on the feedback information from each device of the set of devices. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein each device of the set of devices receives data on one or more data channels, and the feedback information is determined by comparing a percentage of data channels of the one or more data channels and the received signal-to-interference-plus-noise ratio of the data channel resulting in a block error ratio higher than a target block error ratio by a margin percentage with a threshold percentage. ### Claim 12 (depends on 10) The apparatus of claim 10, wherein the feedback information is determined by comparing a block error ratio resulting from the received signal-to-interference-plus-noise ratio with a target block error ratio by a margin percentage. ### Claim 13 (depends on 10) The apparatus of claim 10, wherein each device of the set of devices receives data on one or more data channels, and the feedback information is determined by comparing a percentage of data channels of the one or more data channels and the received signal-to-interference-plus-noise ratio of the data channel resulting in a first modulation and coding scheme lower than a second modulation and coding scheme by a margin level with a threshold percentage. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the first modulation and coding scheme is determined for achieving a target block error ratio based on the received signal-to-interference-plus-noise ratio of the data channel. ### Claim 15 (depends on 13) The apparatus of claim 13, wherein the second modulation and coding scheme is indicated in downlink control information scheduling the data channel. ### Claim 16 (depends on 10) The apparatus of claim 10, wherein the feedback information is determined by comparing a first modulation and coding scheme resulting from the received signal-to-interference-plus-noise ratio with a second modulation and coding scheme by a margin level. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein the first modulation and coding scheme is determined for achieving a target block error ratio based on the received signal-to-interference-plus-noise ratio and the second modulation and coding scheme is indicated in downlink control information. ### Claim 18 (depends on 10) The apparatus of claim 10, wherein: the processor increases the contention window size if the processor determines that more than a predetermined percentage of devices indicates the interference above the predetermined level exists on the carrier during the transmission burst; the processor decreases the contention window size if the processor determines that no more than a predetermined percentage of devices indicates the interference above the predetermined level exists on the carrier during the transmission burst; or a combination thereof. ### Claim 19 (depends on 10) The apparatus of claim 10, wherein: the processor divides the set of devices into two subsets, wherein the first subset includes the devices indicating the interference above the predetermined level exists on the carrier during the transmission burst, and the second subset includes the devices indicating the interference above the predetermined level does not exist on the carrier during the transmission burst. ### Claim 20 (depends on 19) The apparatus of claim 19, wherein the two subsets are updated after the completion of the transmission burst. ### Claim 21 (depends on 19) The apparatus of claim 19, wherein the processor increases the contention window size if the processor intends to schedule one or more devices in the first subset in a next transmission burst. ### Claim 22 (depends on 19) The apparatus of claim 19, wherein the processor decreases the contention window size if the processor does not intend to schedule one or more devices in the first subset in a next transmission burst. ### Claim 23 A method comprising: transmitting data in a first transmission burst on a carrier to a set of devices, wherein the set of devices comprises one or more devices; receiving feedback information from each device of the set of devices, wherein the feedback information indicates whether interference above a predetermined level exists on the carrier during the transmission burst, and the feedback information is determined by each device of the set of devices based on a received signal-to-interference-plus-noise ratio of each device of the set of devices during the transmission burst; and adjusting a contention window size based on the feedback information from each device of the set of devices.