# US 12,192,988 B2 · Device, system, and method for multi-link operations > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,192,988 B2 - Document ID: US12192988B2 - Status: Granted - Kind: B2 - Application number: 17/718,979 - Filed: 2022-04-12 - Published: 2022-10-13 - Granted: 2025-01-07 - Earliest claimed: 2021-04-12 - Assignees: NXP USA, Inc. - Applicants: NXP USA, Inc. - Inventors: Liwen Chu; Young Hoon Kwon; Hongyuan Zhang; Huiling Lou - Web page: https://patentgrep.com/patent/US12192988B2 ## CPC - H04W 72/1263: Mapping of traffic onto schedule, e.g. scheduled allocation or multiplexing of flows - H04W 74/006: {in the downlink, i.e. towards the terminal} - H04W 48/10: using broadcasted information - H04W 76/10: Connection setup - H04W 76/15: Setup of multiple wireless link connections - H04W 84/12: WLAN [Wireless Local Area Networks] - H04W 48/12: using downlink control channel - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A device, a system, and a method for multi-link operations are disclosed. In an embodiment, the device includes a processor configured to generate a frame that includes a Traffic Indication Map (TIM) element, where the TIM element includes a group-addressed buffered frame indication for reported Access Points (APs) that indicates a transmitted Basic Service Set Identifier (BSSID) AP and non-transmitted BSSID APs affiliated with the reported APs, and exchange buffered frames according to the TIM element. ## Claims ### Claim 1 A device comprising: a processor configured to: generate a frame that includes a Traffic Indication Map (TIM) element, wherein the TIM element includes a group-addressed buffered frame indication for reported Access Points (APs) that indicates a transmitted Basic Service Set Identifier (BSSID) AP and non-transmitted BSSID APs affiliated with the reported APs; and exchange buffered frames according to the TIM element; wherein a length of bitmaps included in the group-addressed buffered frame indication is indicated in a Multi-Link Control field of a Multi-Link IE. ### Claim 2 (depends on 1) The device of claim 1, wherein a bitmap per BSSID Index included in a Multi-Link Information Element (IE) indicates whether the TIM element includes the group-addressed buffered frame indication for the reported APs with a non-transmitted BSSID Index; and wherein bitmaps of AP Multi-Link Devices (MLDs) have a same length that is indicated in the Multi-Link IE. ### Claim 3 (depends on 2) The device of claim 2, wherein the bitmap per BSSID Index is included in a Common Info field of the Multi-Link IE, and wherein the length is indicated in a Multi-Link Control field of the Multi-Link IE. ### Claim 4 (depends on 1) The device of claim 1, wherein a bitmap of the group-addressed buffered frame indication is after a bitmap of an individual-addressed buffered frame indication. ### Claim 5 (depends on 4) The device of claim 4, wherein an ending of the bitmap of the individual-addressed buffered frame indication is indicated by an N2 field; and wherein non-AP MLDs with an Association Identifier (AID) value related to a bit at a location more than (N2+1)*8 do not have bits for individual-addressed buffered frame indications. ### Claim 6 (depends on 1) The device of claim 1, wherein a bitmap of the group-addressed buffered frame indication for a non-transmitted BSSID AP with a BSSID Index is excluded from a Partial Virtual Bitmap field of the TIM element if at least one of: the bitmap includes all zero bits; the BSSID Index does not correspond to the non-transmitted BSSID; and the bitmap related to the BSSID Index has zero bits for a larger BSSID Index. ### Claim 7 (depends on 1) The device of claim 1, wherein a bitmap per BSSID Index included in the TIM element indicates whether the TIM element includes the group-addressed buffered frame indication for the reported APs with a non-transmitted BSSID Index; and wherein bitmaps of AP MLDs have a same length that is indicated in a Multi-Link IE. ### Claim 8 (depends on 1) The device of claim 1, wherein a non-AP MLD ignores the group-addressed buffered frame indication from a Partial Virtual Bitmap field of the TIM element if at least one of: the reported APs that Stations (STAs) of the non-AP MLD are associated with do not have the buffered frames and a Bitmap Offset subfield; the Bitmap Offset subfield and a Length field describe the ignoring; AIDs of the reported APs are smaller than a smallest AID value described by the Partial Virtual Bitmap field; and AIDs of the reported APs are larger than a largest AID value described by the Partial Virtual Bitmap field. ### Claim 9 (depends on 1) The device of claim 1, wherein the device allocates smaller AID values to STAs that do not support multi-link operation than AID values allocated to other STAs affiliated with non-AP MLDs. ### Claim 10 (depends on 1) The device of claim 1, wherein an AID value of the reported APs is announced in a Multi-Link IE of Beacon frames. ### Claim 11 (depends on 1) The device of claim 1, wherein when the device establishes a multi-link association with a non-AP MLD, the device announces an AID value for APs with which the non-AP MLD establishes a connection. ### Claim 12 (depends on 1) The device of claim 1, wherein the frame includes a Multi-link Traffic IE that indicates Traffic Identifiers (TIDs) mapped to different links. ### Claim 13 (depends on 1) The device of claim 1, wherein the frame includes a Multi-link Traffic IE if at least one associated non-AP MLD with negotiated TID-to-link mapping is associated with the device, and the device has the buffered frames for the non-AP MLD; and wherein the Multi-link Traffic IE is included in a Beacon frame and in a Broadcast frame if transmitted by an AP of the at least one associated non-AP MLD. ### Claim 14 (depends on 1) The device of claim 1, wherein the frame includes a Multi-link Traffic IE if at least one associated non-AP MLD with negotiated TID-to-link mapping is associated with the device, wherein different TIDs are mapped to the different links, and the device has the buffered frames for the non-AP MLD; and wherein the Multi-link Traffic IE is included in a Beacon frame and in a broadcast frame if transmitted by an AP of the at least one associated non-AP MLD. ### Claim 15 (depends on 1) The device of claim 1, wherein the frame optionally includes a Multi-link Traffic IE if at least one associated non-AP MLD with negotiated TID-to-link mapping is associated with the device, wherein different TIDs are mapped to the different links, and the device does not have the buffered frames for the non-AP MLD; and wherein the Multi-link Traffic IE is optionally included in a Beacon frame and in a broadcast frame if transmitted by an AP of the at least one associated non-AP MLD. ### Claim 16 (depends on 1) The device of claim 1, wherein the frame includes a Multi-link Traffic IE that indicates, for each non-AP MLD with negotiated TID-to-link mapping, links that include the buffered frames. ### Claim 17 (depends on 1) The device of claim 1, wherein the frame includes a Multi-link Traffic IE that includes a link ID bitmap when a link bitmap has a length different from sixteen, and wherein the link ID bitmap includes: a first bit that corresponds to a link that has an AP with a smallest link ID value; a last bit that corresponds to another link that has another AP with a largest link ID value; a link ID value that is related to a bit that is less than another link ID value related to another bit that is after the bit; and if a number of bits in the link ID bitmap is more than a number of links of the device, then least significant bit (LSB) bits related to the number of the links with APs of the device are used. ### Claim 18 A device comprising: a processor configured to: generate a frame that includes a Traffic Indication Map (TIM) element, wherein the TIM element includes a group-addressed buffered frame indication for reported Access Points (APs) that indicates a transmitted Basic Service Set Identifier (BSSID) AP and non-transmitted BSSID APs affiliated with the reported APs; and exchange buffered frames according to the TIM element; wherein an AID value of the reported APs is announced in a Multi-Link IE of Beacon frames. ### Claim 19 A device comprising: a processor configured to: generate a frame that includes a Traffic Indication Map (TIM) element, wherein the TIM element includes a group-addressed buffered frame indication for reported Access Points (APs) that indicates a transmitted Basic Service Set Identifier BSSID) AP and non-transmitted BSSID APs affiliated with the reported APs; and exchange buffered frames according to the TIM element; wherein the frame includes a Multi-link Traffic IE that indicates Traffic Identifiers (TIDs) mapped to different links.