# US 12,003,341 B2 · Communication method and communications apparatus for reduction of transmission latency of downlink data > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,003,341 B2 - Document ID: US12003341B2 - Status: Granted - Kind: B2 - Application number: 17/214,412 - Filed: 2021-03-26 - Published: 2021-07-15 - Granted: 2024-06-04 - Earliest claimed: 2018-09-26 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Ruixiang Ma; Shengyu Li; Lei Guan - Web page: https://patentgrep.com/patent/US12003341B2 ## CPC - H04L 1/1854: {Scheduling and prioritising arrangements} - H04L 1/1896: {ARQ related signaling} - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04L 5/0082: {at predetermined intervals} - H04W 72/0446: Resources in time domain, e.g. slots or frames - H04W 72/1273: of downlink data flows - H04W 72/535: {based on resource usage policies} - H04L 1/1864: {ARQ related signaling (H04L1/1607 takes precedence)} - H04L 5/0023: {Time-frequency-space} - 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 A communication method includes: a terminal device determining a first time unit for receiving downlink data, determining, based on a nonnegative integer k1 corresponding to the downlink data, a second time unit in which feedback information corresponding to the downlink data is located, where a length of the first time unit is greater than or equal to a length of the second time unit, k1 represents a quantity of time units from the first time unit to the second time unit, and the length of the second time unit is less than one slot, and sending, in the second time unit, a feedback codebook to the network device, where the feedback codebook includes the feedback information corresponding to the downlink data. A transmission latency of downlink data is reduced. ## Claims ### Claim 1 A communication method, the method comprising: determining, by a terminal device, a first time unit for receiving downlink data; determining, by the terminal device, based on a nonnegative integer k1 corresponding to the downlink data, a second time unit in which feedback information corresponding to the downlink data is located, wherein a length of the first time unit is greater than or equal to a length of the second time unit, the k1 corresponding to the downlink data represents a quantity of time units from the first time unit to the second time unit in which feedback information corresponding to the downlink data is located, and the length of the second time unit is less than one slot; and sending, by the terminal device, in the second time unit in which feedback information corresponding to the downlink data is located, a feedback codebook to a network device, wherein the feedback codebook comprises the feedback information corresponding to the downlink data, wherein the feedback codebook comprises feedback information corresponding to a candidate occasion of a target second time unit, the candidate occasion is used by the terminal device to receive downlink data, and the target second time unit is a set of second time units that is determined based on a k1 set and the second time unit in which the feedback information corresponding to the downlink data is located, and the k1 set is a set of values of k1, and the candidate occasion is determined based on configured time domain resources used by the terminal device to receive downlink data, wherein the configured time domain resources comprise a time domain resource whose last symbol belongs to the target second time unit. ### Claim 2 (depends on 1) The method according to claim 1, wherein based on that the length of the first time unit is greater than the length of the second time unit, and k1 is equal to 0, the second time unit is the last second time unit in a third time unit, and the third time unit is a first time unit whose number is the same as that of the first time unit for receiving the downlink data. ### Claim 3 (depends on 1) The method according to claim 1, wherein the length of the first time unit is equal to one slot. ### Claim 4 (depends on 1) The method according to claim 1, wherein the feedback codebook comprises feedback information corresponding to a candidate occasion of a target first time unit, and the candidate occasion is used by the terminal device to receive the downlink data, the target first time unit is a set of first time units in which the target second time unit is located, the length of the first time unit is greater than the length of the second time unit, and the target first time unit comprises the first time unit for receiving the downlink data. ### Claim 5 (depends on 1) The method according to claim 1, wherein the feedback codebook comprises feedback information corresponding to a target candidate occasion, the target candidate occasion comprises at least one of: a candidate occasion in which the last symbol of a target fourth time unit belongs to the target second time unit, or a candidate occasion in which the first symbol of the target fourth time unit belongs to the target second time unit, the candidate occasion is used by the terminal device to receive the downlink data, and the target candidate occasion comprises the candidate occasion for receiving the downlink data, the target fourth time unit is a set of fourth time units in which the target second time unit is located, and a length of the fourth time unit is greater than the length of the second time unit. ### Claim 6 (depends on 1) The method according to claim 1, wherein the length of the second time unit is equal to a half of one slot. ### Claim 7 A communication method, the method comprising: sending, by a network device, downlink data to a terminal device in a first time unit; determining, by the network device, based on a nonnegative integer k1 corresponding to the downlink data, a second time unit in which feedback information corresponding to the downlink data is located, wherein a length of the first time unit is greater than or equal to a length of the second time unit, the k1 corresponding to the downlink data represents a quantity of time units from the first time unit to the second time unit in which feedback information corresponding to the downlink data is located, and the length of the second time unit is less than one slot; and receiving, by the network device, in the second time unit in which feedback information corresponding to the downlink data is located, a feedback codebook from the terminal device, wherein the feedback codebook comprises the feedback information corresponding to the downlink data, wherein the feedback codebook comprises feedback information corresponding to a candidate occasion of a target second time unit, the candidate occasion is used by the terminal device to receive downlink data, and the target second time unit is a set of second time units that is determined based on a k1 set and the second time unit in which the feedback information corresponding to the downlink data is located, and the k1 set is a set of values of k1, and the candidate occasion is determined based on configured time domain resources used by the terminal device to receive downlink data, wherein the configured time domain resources comprise a time domain resource whose last symbol belongs to the target second time unit. ### Claim 8 (depends on 7) The method according to claim 7, wherein based on that the length of the first time unit is greater than the length of the second time unit, and k1 is equal to 0, the second time unit is the last second time unit in a third time unit, and the third time unit is a first time unit whose number is the same as that of the first time unit for sending the downlink data. ### Claim 9 (depends on 7) The method according to claim 7, wherein the length of the first time unit is equal to one slot. ### Claim 10 (depends on 7) The method according to claim 7, wherein the feedback codebook comprises feedback information corresponding to a candidate occasion of a target first time unit, and the candidate occasion is used by the terminal device to receive the downlink data, and wherein the target first time unit is a set of first time units in which the target second time unit is located, the length of the first time unit is greater than the length of the second time unit, and the target first time unit comprises the first time unit for sending the downlink data to the terminal device. ### Claim 11 (depends on 7) The method according to claim 7, wherein the feedback codebook comprises feedback information corresponding to a target candidate occasion, the target candidate occasion comprises at least one of a candidate occasion in which the last symbol of a target fourth time unit belongs to the target second time unit, or a candidate occasion in which the first symbol of the target fourth time unit belongs to the target second time unit, the candidate occasion is used by the terminal device to receive the downlink data, and the target candidate occasion comprises the candidate occasion for sending the downlink data to the terminal device; and wherein the target fourth time unit is a set of fourth time units in which the target second time unit is located, and a length of the fourth time unit is greater than the length of the second time unit. ### Claim 12 (depends on 7) The method according to claim 7, wherein the length of the second time unit is equal to a half of one slot. ### Claim 13 A communications apparatus, the apparatus comprising: a processor, configured to determine a first time unit for receiving downlink data, wherein the processor is further configured to determine, based on a nonnegative integer k1 corresponding to the downlink data, a second time unit in which feedback information corresponding to the downlink data is located, a length of the first time unit is greater than or equal to a length of the second time unit, the k1 corresponding to the downlink data represents a quantity of time units from the first time unit to the second time unit in which feedback information corresponding to the downlink data is located, and the length of the second time unit is less than one slot; and a transceiver, configured to send, in the second time unit in which feedback information corresponding to the downlink data is located determined by the processor, a feedback codebook to a network device, wherein the feedback codebook comprises the feedback information corresponding to the downlink data, wherein the feedback codebook comprises feedback information corresponding to a candidate occasion of a target second time unit, the candidate occasion is used by the communications apparatus to receive downlink data, and the target second time unit is a set of second time units that is determined based on a k1 set and the second time unit in which the feedback information corresponding to the downlink data is located, and the k1 set is a set of values of k1, and the candidate occasion is determined based on configured time domain resources used by the communications apparatus to receive the downlink data, wherein the configured time domain resources comprise a time domain resource whose last symbol belongs to the target second time unit. ### Claim 14 (depends on 13) The apparatus according to claim 13, wherein based on that the length of the first time unit is greater than the length of the second time unit, and k1 is equal to 0, the second time unit is the last second time unit in a third time unit, and the third time unit is a first time unit whose number is the same as that of the first time unit for receiving the downlink data. ### Claim 15 (depends on 13) The apparatus according to claim 13, wherein the length of the first time unit is equal to one slot. ### Claim 16 A communications apparatus, the apparatus comprising: a transceiver, configured to send downlink data to a terminal device in a first time unit; and a processor, configured to determine, based on a nonnegative integer k1 corresponding to the downlink data sent by the transceiver, a second time unit in which feedback information corresponding to the downlink data is located, a length of the first time unit is greater than or equal to a length of the second time unit, the k1 corresponding to the downlink data represents a quantity of time units from the first time unit to the second time unit in which feedback information corresponding to the downlink data is located, and the length of the second time unit is less than one slot, wherein the transceiver is further configured to receive, in the second time unit in which feedback information corresponding to the downlink data is located determined by the processor, a feedback codebook from the terminal device, wherein the feedback codebook comprises the feedback information corresponding to downlink data, wherein the feedback codebook comprises feedback information corresponding to a candidate occasion of a target second time unit, the candidate occasion is used by the terminal device to receive the downlink data, and the target second time unit is a set of second time units that is determined based on a k1 set and the second time unit in which the feedback information corresponding to the downlink data is located, and the k1 set is a set of values of k1, and the candidate occasion is determined based on configured time domain resources used by the terminal device to receive the downlink data, wherein the configured time domain resources comprise a time domain resource whose last symbol belongs to the target second time unit. ### Claim 17 (depends on 16) The apparatus according to claim 16, wherein based on that the length of the first time unit is greater than the length of the second time unit, and k1 is equal to 0, the second time unit is the last second time unit in a third time unit, and the third time unit is a first time unit whose number is the same as that of the first time unit for sending the downlink data. ### Claim 18 (depends on 16) The apparatus according to claim 16, wherein the length of the first time unit is equal to one slot.