# US 12,604,341 B2 · Method and apparatus for exchanging frames using secondary channels > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,604,341 B2 - Document ID: US12604341B2 - Status: Granted - Kind: B2 - Application number: 18/216,500 - Filed: 2023-06-29 - Published: 2024-01-04 - Granted: 2026-04-14 - Earliest claimed: 2022-06-29 - Assignees: NXP USA, Inc. - Applicants: NXP USA, Inc. - Inventors: Liwen Chu; Rui Cao; Hongyuan Zhang; Kiseon Ryu; Huizhao Wang - Web page: https://patentgrep.com/patent/US12604341B2 ## CPC - H04W 74/0816: with collision avoidance - 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 method and an apparatus for operating a Basic Service Set (BSS) are disclosed. A method involves announcing, by a first wireless device to a second wireless device, a BSS operating channel, wherein the first wireless device has at least one of a first transmission power capability and a first bandwidth capability, the second wireless device has at least one of a second transmission power capability that is less than the first transmission power capability and a second bandwidth capability that is narrower than the first bandwidth capability, and wherein the BSS operating channel is at least one of a punctured operating channel and an unpunctured operating channel, associating, by the second wireless device, with the first wireless device via the announcement of the BSS operating channel from the first wireless device, and exchanging frames between the first wireless device and the second wireless device in the BSS operating channel. ## Claims ### Claim 1 A device comprising: a controller configured to: announce multiple subchannels of a basic service set (BSS) operating channel, wherein each of the multiple subchannels includes a single backoff channel and at least one another channel; negotiate a secondary parking subchannel among the multiple subchannels of the BSS operating channel in a link between the device and another device; and exchange frames between the device and the another device using the secondary parking subchannel, including switching to the secondary parking subchannel from a different subchannel of the BSS operating channel to exchange the frames using the secondary parking subchannel; wherein the controller is configured to negotiate the secondary parking subchannel among the multiple subchannels of the BSS operating channel in the link between the device and the another device during a broadcast target wake time (TWT) membership negotiation. ### Claim 2 (depends on 1) The device of claim 1, wherein the controller is configured to request the another device to switch to a subchannel of the multiple subchannels of the BSS operating channel other than the secondary parking subchannel during a transmission opportunity (TXOP) period. ### Claim 3 (depends on 1) The device of claim 1, wherein the controller is configured to code a Resource Unit (RU) index of a RU as an RU index per a bandwidth of the BSS operating channel or as an RU index per a bandwidth of a transmission opportunity (TXOP) period. ### Claim 4 (depends on 1) The device of claim 1, wherein the controller is configured to, when a bandwidth (BW) of a transmission opportunity (TXOP) period covers multiple backoff channels, update Enhanced Distribution Channel Access (EDCA) parameters of a particular backoff channel that initiated the TXOP period or the EDCA parameters of each of the multiple backoff channels with an Association Identifier (AID) that is same as an AID of a particular backoff channel that initiated the TXOP period. ### Claim 5 A device comprising: a controller configured to: announce multiple subchannels of a basic service set (BSS) operating channel, wherein each of the multiple subchannels includes a single backoff channel and at least one another channel; negotiate a secondary parking subchannel among the multiple subchannels of the BSS operating channel in a link between the device and another device; and exchange frames between the device and the another device using the secondary parking subchannel, including switching to the secondary parking subchannel from a different subchannel of the BSS operating channel to exchange the frames using the secondary parking subchannel; wherein the controller is configured to negotiate the secondary parking subchannel among the multiple subchannels of the BSS operating channel in the link between the device and the another device using a beacon transmitted through a duplicate Physical Layer Protocol Data Unit (PPDU), and wherein at least one of the first and second multi-link devices can perform simultaneous backoff operations in more than one of the multiple subchannels. ### Claim 6 A device comprising: a controller configured to: announce multiple subchannels of a basic service set (BSS) operating channel, wherein each of the multiple subchannels includes a single backoff channel and at least one another channel; negotiate a secondary parking subchannel among the multiple subchannels of the BSS operating channel in a link between the device and another device; and exchange frames between the device and the another device using the secondary parking subchannel, including switching to the secondary parking subchannel from a different subchannel of the BSS operating channel to exchange the frames using the secondary parking subchannel; wherein the controller is configured to manage medium synchronization in a subchannel of the BSS operating channel after the medium synchronization is lost at the end of a transmission opportunity (TXOP) period that does not cover the subchannel from the beginning to the end of the TXOP period. ### Claim 7 A device comprising: a controller configured to: announce multiple subchannels of a basic service set (BSS) operating channel, wherein each of the multiple subchannels includes a single backoff channel and at least one another channel; negotiate a secondary parking subchannel among the multiple subchannels of the BSS operating channel in a link between the device and another device; and exchange frames between the device and the another device using the secondary parking subchannel, including switching to the secondary parking subchannel from a different subchannel of the BSS operating channel to exchange the frames using the secondary parking subchannel; wherein the controller is configured to, when backoff counters in the multiple subchannels become zero at the same time, using a backoff counter with the highest priority access category (AC) to initiate a transmission opportunity (TXOP) period. ### Claim 8 (depends on 7) The device of claim 7, wherein the backoff counter with the highest priority AC is in the primary channel when more than one backoff counters have the same highest priority AC.