# US 12,604,355 B2 · Link error recovery method and apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,604,355 B2 - Document ID: US12604355B2 - Status: Granted - Kind: B2 - Application number: 18/149,490 - Filed: 2023-01-03 - Published: 2023-05-11 - Granted: 2026-04-14 - Earliest claimed: 2020-07-10 - Assignees: Nokia Technologies Oy - Applicants: Nokia Technologies OY - Inventors: Yiqing Li; Yunbo Li; Yuchen Guo; Ming Gan - Web page: https://patentgrep.com/patent/US12604355B2 ## CPC - H04L 1/1614: {using bitmaps} - H04W 76/18: Management of setup rejection or failure - H04L 1/1887: {Scheduling and prioritising arrangements} - H04W 76/15: Setup of multiple wireless link connections - H04W 76/19: Connection re-establishment - 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 link error recovery method applied to a transmitter MLD is provided. Links between the transmitter MLD and a receiver MLD include a first link and a second link, and one of the transmitter MLD and the receiver MLD has an STR capability while the other does not have the STR capability. The method includes: determining that transmission of a first PPDU on the first link fails; and transmitting a second PPDU to the receiver MLD at a first moment by using the first link, the second PPDU being used to retransmit an error part in the first PPDU. The first moment is a moment at which the transmitter MLD obtains transmission status information of the second link. Alternatively, the first moment is a moment for transmitting a next PPDU on the first link if the first PPDU is normally transmitted. ## Claims ### Claim 1 A link error recovery method, wherein the method is applied to a transmitter multi-link device (MLD), links between the transmitter MLD and a receiver MLD comprise a first link and a second link, and the method comprises: transmitting, by a transmitter MLD to a receiver MLD a first physical protocol data unit (PPDU) over a first link, wherein: the transmitter MLD and receiver MLD have the first link and a second link therebetween; and one of the transmitter MLD and receiver MLD has a simultaneous transmitting and receiving (STR) capability while the other does not have the STR capability; determining, by the transmitter MLD, that transmission of the PPDU on the first link fails wherein the failure is because only one of the transmitter and receiver has STR capability; and transmitting, by the transmitter MLD, a second PPDU to the receiver MLD at a first moment through the first link, wherein the second PPDU comprises a retransmitted error part from the first PPDU, wherein the first moment is a moment at which the transmitter MLD obtains transmission status information of the second link, and the transmission status information of the second link indicates that transmission of a third PPDU on the second link fails; or the first moment is a moment for transmitting a next PPDU on the first link assuming that the first PPDU is normally transmitted. ### Claim 2 (depends on 1) The method according to claim 1, wherein the first moment is the moment at which the transmitter MLD obtains transmission status information of the second link, and an interval between the moment at which the transmitter MLD obtains the transmission status information of the second link and a predicted start moment of a first block acknowledgement (BA) is less than or equal to a first duration, wherein the first BA is a BA of the first PPDU, and the first duration is a sum of a length of the first BA and a short interframe space (SIFS). ### Claim 3 (depends on 1) The method according to claim 1, wherein the first moment is the moment at which the transmitter MLD obtains transmission status information of the second link, and obtaining, by the transmitter MLD, the transmission status information of the second link comprises: receiving, by a first station, the transmission status information of the second link from a second station, wherein the first station is a station that is in the transmitter MLD and supports the first link, and the second station is a station that is in the transmitter MLD and supports the second link. ### Claim 4 (depends on 1) The method according to claim 1, wherein an end moment of the second PPDU is the same as that of a fourth PPDU on the second link, and the fourth PPDU comprises a retransmitted error part from the third PPDU. ### Claim 5 (depends on 1) The method according to claim 1, wherein the transmitter MLD is an access point (AP) MLD, and the receiver MLD is a non-STR station MLD. ### Claim 6 A transmitter multi-link device (MLD), comprising: at least one memory, configured to store computer instructions; and at least one processor, configured to perform the computer instructions to cause the transmitter MLD to: determine that transmission of a first physical protocol data unit (PPDU) on a first link fails; and transmit a second PPDU to a receiver MLD at a first moment through the first link, wherein the second PPDU comprises a retransmitted error part from the first PPDU; wherein the first moment is a moment at which the transmitter MLD obtains transmission status information of a second link, and the transmission status information of the second link indicates that transmission of a third PPDU on the second link fails; or the first moment is a moment for transmitting a next PPDU on the first link assuming that the first PPDU is normally transmitted; wherein the first link and the second link are links between the transmitter MLD and the receiver MLD, one of the transmitter MLD and the receiver MLD has a simultaneous transmitting and receiving (STR) capability while the other does not have the STR capability. ### Claim 7 (depends on 6) The transmitter MLD according to claim 6, wherein the first moment is the moment at which the transmitter MLD obtains transmission status information of the second link, and an interval between the moment at which the transmitter MLD obtains the transmission status information of the second link and a predicted start moment of a first block acknowledgement (BA) is less than or equal to a first duration, wherein the first BA is a BA of the first PPDU, and the first duration is a sum of a length of the first BA and a short interframe space (SIFS). ### Claim 8 (depends on 6) The transmitter MLD according to claim 6, wherein an end moment of the second PPDU is the same as that of a fourth PPDU on the second link, and the fourth PPDU comprises a retransmitted error part from the third PPDU. ### Claim 9 (depends on 6) The transmitter MLD according to claim 6, wherein the transmitter MLD is an access point (AP) MLD, and the receiver MLD is a non-STR station MLD. ### Claim 10 A non-transitory computer readable storage medium storing computer instructions, which when executed by at least one processor, cause a transmitter multi-link device (MLD) comprising the at least one processor to: transmit, by a transmitter MLD to a receiver MLD a first physical protocol data unit (PPDU) over a first link, wherein: the transmitter MLD and receiver MLD have the first link and a second link therebetween; and one of the transmitter MLD and receiver MLD has a simultaneous transmitting and receiving (STR) capability while the other does not have the STR capability; determine that transmission of the PPDU on the first link fails, wherein the failure is because only one of the transmitter and receiver has STR capability; and transmit a second PPDU to a receiver MLD at a first moment through the first link, wherein the second PPDU comprises a retransmitted error part from the first PPDU; wherein the first moment is a moment at which the transmitter MLD obtains transmission status information of a second link, and the transmission status information of the second link indicates that transmission of a third PPDU on the second link fails; or the first moment is a moment for transmitting a next PPDU on the first link assuming that the first PPDU is normally transmitted; wherein the first link and the second link are links between the transmitter MLD and the receiver MLD. ### Claim 11 (depends on 10) The non-transitory computer readable storage medium according to claim 10, wherein the first moment is the moment at which the transmitter MLD obtains transmission status information of the second link, and an interval between the moment at which the transmitter MLD obtains the transmission status information of the second link and a predicted start moment of a first block acknowledgement (BA) is less than or equal to a first duration, wherein the first BA is a BA of the first PPDU, and the first duration is a sum of a length of the first BA and a short interframe space (SIFS). ### Claim 12 (depends on 10) The non-transitory computer readable storage medium according to claim 10, wherein an end moment of the second PPDU is the same as that of a fourth PPDU on the second link, and the fourth PPDU comprises a retransmitted error part from the third PPDU. ### Claim 13 (depends on 10) The non-transitory computer readable storage medium according to claim 10, wherein the transmitter MLD is an access point (AP) MLD, and the receiver MLD is a non-STR station MLD.