A method of communication and a communication apparatus

Abstract

A method and a communication device for communication can be applied to a WLAN system supporting IEEE 802.11ax next-generation Wi-Fi protocol, such as 802.11be, again such as 802.11bn, again such as 802.11bn next-generation, and the like 802.11 series protocol, and can also be applied to a wireless personal area network system based on UWB and a sensing system. In the method, when a first station detects interaction of an OBSS station about unavailable information, the first station can enable NPCA based on the length of a PPDU, that is, in the case of detecting a PPDU meeting the condition of triggering NPCA, switching from a main channel to an NPCA main channel, and switching back to the main channel based on the end time of the PPDU, so as to switch back to the main channel in time for channel competition, and avoid wasting transmission resources of the main channel.

Description

[0001] This application is a divisional application. The original application has the application number 202510346901.4 and the original application date is March 21, 2025. The entire contents of the original application are incorporated herein by reference. Technical Field

[0002] This application relates to the field of communications, and more specifically, to a method and apparatus for channel access. Background Technology

[0003] In a wireless local area network (WLAN), when access points (APs) and non-AP stations (STAs) communicate, they typically access each other on the primary channel, a mechanism known as primary channel access. However, when the primary channel is busy and the non-primary channel is idle, according to the primary channel access mechanism, the station (such as an AP or non-AP STA) will determine that the entire channel is unavailable, thus wasting the resources of the non-primary channel. Therefore, the standard introduces the non-primary channel access (NPCA) mechanism. When the primary channel is busy, the station can switch to a sub-channel of a non-primary channel to compete for channel resources, thereby enabling communication on the non-primary channel.

[0004] However, the existing NPCA mechanism may lead to problems such as resource waste and transmission failures. Summary of the Invention

[0005] This application provides a communication method and communication device that can improve resource utilization.

[0006] In a first aspect, a communication method is provided, which can be applied to a first station, for example, can be performed by the first station or by a component of the first station (e.g., a chip or circuit or chip system).

[0007] The method includes: receiving a first frame from a second station on a first primary channel, wherein the first frame is used to solicit or request unavailability information from a station associated with the second station, or the first frame is used to carry unavailability information from the second station, wherein the basic service set (BSS) to which the second station belongs and the BSS to which the first station belongs are overlapping basic service sets (OBSS); detecting a first physical protocol data unit (PPDU) within the transmission opportunity (TXOP) where the first frame is located, and the first PPDU satisfies the conditions for triggering NPCA, switching from the first primary channel to a second primary channel, wherein the second primary channel is the NPCA primary channel, and the first PPDU is a PPDU sent by the second station or a station associated with the second station; and switching from the second primary channel to the first primary channel based on the end time of the first PPDU.

[0008] Based on the above scheme, when the first station detects the interaction of the OBSS station with unavailability information, the first station can enable NPCA based on the PPDU length. That is, when a PPDU that meets the conditions for triggering NPCA is detected, the first station switches from the main channel to the NPCA main channel, and switches back to the main channel based on the end time of the PPDU. In this way, the first station can switch back to the main channel in a timely manner to compete for the channel and avoid wasting the transmission resources of the main channel.

[0009] For example, the conditions for triggering NPCA include: the duration of the first PPDU occupying the first main channel is greater than the second threshold, and the channel occupied by the first PPDU and the second main channel do not overlap.

[0010] For example, the TXOP containing the first frame is the time period from the start time of the first frame to the end time of the second station sending the TXOP end indication, or the time period from the start time of the first frame to the end of the countdown of the NAV timer set by the first station according to the first frame. Therefore, detecting the first PPDU within the TXOP containing the first frame can be replaced by: detecting the first PPDU before the first station receives the TXOP end indication, or detecting the first PPDU before the countdown of the NAV timer set according to the first frame ends.

[0011] In conjunction with the first aspect, in some implementations, the first frame is a first initial control frame (ICF), which satisfies at least one of the following conditions: The first ICF is a buffer status report poll (BSRP) frame, which includes response type indication information to indicate that the response type of the first frame is unavailable information feedback; or, the first ICF is a BSRP frame, which includes ICF type indication information to indicate that the first ICF is used to query for unavailable information; or, the first ICF is a BSRP frame, which includes a guard interval and high efficient / ultra high reliability long training fieldtype (GI And HE / UHR -LTF Type) field, where the value of the GI And HE / UHR -LTF Type field is 3; or, the first ICF is a BSRP frame, which includes an uplink length (UL) field. The uplink length field has a value greater than the first threshold; or, the first ICF is a BSRP frame, which includes a carrier sensing (CS) required field with a value of 1.

[0012] Based on the above scheme, the first station can use the information carried in the ICF as a judgment condition without the need for additional indication information. This allows for more efficient use of non-main channel resources while avoiding wasting main channel access opportunities.

[0013] In addition, ICF can contain more information and is easier to decode, which can improve the processing efficiency of the first station and save power.

[0014] In conjunction with the first aspect, in some implementations, the first frame is used to carry unavailability information of the second station. The first frame is a first initial control response (ICR) frame, and the first ICR frame is a multi-STA block ack (Multi-STA BA or Multi-STA BlockAck) frame. The multi-STA block ack frame satisfies at least one of the following conditions: the multi-STA block ack frame includes unavailability information of the second station; or, the PPDU carrying the multi-STA block ack frame is a non-high throughput (non-HT) PPDU; or, the value of the legacy signal length (L-SIG LENGTH) field in the PPDU carrying the multi-STA block ack frame is greater than a first threshold. For example, the L-SIG LENGTH field is located in the legacy signal (L-SIG) field of the PPDU, and it can indicate the length of the PPDU. It should be understood that in this application, the L-SIG field can also be called the non-HTSIGNAL field, and therefore, the L-SIG LENGTH field can also be called the non-HT SIGNALLENGTH field.

[0015] Based on the above scheme, the first station can use the information carried in the ICR as a judgment condition without the need for additional indication information. This allows for more efficient use of non-main channel resources while avoiding wasting main channel access opportunities.

[0016] In conjunction with the first aspect, in some implementations, the first frame is the first ICF, which includes first indication information and / or second indication information. The first indication information is used to indicate that there is a possibility of an update in the TXOP where the first ICF is located, and the second indication information is used to indicate that the type of NPCA performed by the site that is an OBSS with the BSS to which the second site belongs in the TXOP where the first ICF is located is an NPCA based on the PPDU length.

[0017] Based on the above scheme, by adding first indication information to the first ICF, other stations can be clearly informed whether the TXOP of the second station may be shortened. Thus, the first station can take corresponding NPCA actions based on the first indication information, thereby improving channel utilization efficiency. Alternatively, by adding second indication information to the first ICF, the first station can clearly know from the indication bit which type of NPCA should be performed, maximizing the utilization of NPCA main channel resources while avoiding wasting main channel access opportunities.

[0018] For example, in this implementation, the first ICF is a BSRP frame, the first indication information is carried in the Common Info field or the Special User Info field of the BSRP frame, and the second indication information is carried in the Common Info field or the Special User Info field of the BSRP frame; or, the first ICF is a multi-user request to send (MU-RTS) frame, the first indication information is carried in the Common Info field or the Special User Info field of the MU-RTS frame, and the second indication information is carried in the Common Info field or the Special User Info field of the MU-RTS frame.

[0019] Optionally, the first indication information is also used to indicate whether the second station allows the first station to reset the network allocation vector (NAV) timer set according to the first ICF.

[0020] Based on the above scheme, the first station can reset the NAV timer when the TXOP of the second station is shortened, so as to avoid wasting the access opportunity of the main channel.

[0021] Optionally, the method further includes: determining, based on the first indication information, whether to perform an opportunistic power save within the TXOP where the first ICF is located.

[0022] Based on the above scheme, the first station can also determine whether to perform opportunistic energy saving within the TXOP where the first ICF is located, thus saving power consumption without wasting the main channel access opportunity.

[0023] In conjunction with the first aspect, in some implementations, the first PPDU includes first indication information and / or second indication information. The first indication information is used to indicate that there is a possibility of an update in the transmission opportunity TXOP where the first PPDU is located. The second indication information is used to indicate that the type of NPCA performed by the station that is an OBSS with the BSS to which the second station belongs within the TXOP where the first PPDU is located is an NPCA based on the PPDU length. The TXOP where the first PPDU is located and the TXOP where the first frame is located are the same TXOP.

[0024] For example, the first indication information is carried in the preamble of the first PPDU.

[0025] Based on the above scheme, the first indication information and / or the second indication information can be directly located in the first PPDU, so that when the first station detects the first PPDU, it can obtain the latest information of TXOP or directly obtain the type of NPCA, which facilitates the first station to make timely decisions.

[0026] In conjunction with the first aspect, in some implementations, the first station is the first non-AP STA. Before receiving the first frame, the method further includes: receiving second indication information from the first AP on the first main channel. The second indication information is used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on PPDU length, wherein the non-AP STA associated with the first AP includes the first non-AP STA.

[0027] Based on the above scheme, the first AP can indicate the type of NPCA to be performed to its associated non-AP STA, so that the non-AP STA can select the appropriate NPCA scheme and improve resource utilization.

[0028] In conjunction with the first aspect, in some implementations, the first station is the first AP. Before receiving the first frame, the method further includes: if it is determined that the second station has enabled the (dynamic unavailability operation, DUO) mode, sending second indication information on the first main channel, the second indication information being used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the PPDU length.

[0029] Based on the above scheme, the first AP can indicate the type of NPCA to be performed to its associated non-AP STA based on whether the OBSS site has enabled DUO mode. This allows the non-AP STA to perform appropriate NPCA, thereby avoiding the waste of main channel resources.

[0030] For example, the second indication information is carried in the beacon frame and / or probe response frame.

[0031] Secondly, a communication method is provided that can be applied to a second station, for example, it can be executed by the second station or by components of the second station (e.g., chips, circuits, or chip systems).

[0032] The method includes: generating first indication information, the first indication information being used to indicate whether there is a possibility of updating the first TXOP, the first TXOP being the TXOP where the first ICF carrying the first indication information is located, or the TXOP where the first PPDU carrying the first indication information is located; and transmitting the first indication information on the first main channel.

[0033] Based on the above scheme, the second station can indicate to other stations whether its TXOP may be updated, such as shortened, so as to promptly publish the latest information of the TXOP and facilitate the communication decisions of other stations.

[0034] In conjunction with the second aspect, in some implementations, the first indication information is carried in the first ICF, which is a BSRP frame, and the first indication information is carried in the common information field or special user information field of the BSRP frame; or, the first indication information is carried in the first ICF, which is a MU-RTS frame, and the first indication information is carried in the common information field or special user information field of the MU-RTS frame; or, the first indication information is carried in the preamble of the first PPDU.

[0035] Optionally, the first indication information is carried in the first ICF, and the first indication information is also used to indicate whether the second station allows the first station to reset the NAV timer set according to the first ICF, and the BSS to which the second station belongs and the BSS to which the first station belongs are each other's OBSS.

[0036] Thirdly, a communication method is provided, which can be applied to a first station, for example, can be executed by the first station or by a component of the first station (e.g., a chip or circuit or chip system).

[0037] The method includes: receiving first indication information on a first main channel, the first indication information being used to indicate whether there is a possibility of updating a first TXOP, the first TXOP being either the TXOP where a first ICF carrying the first indication information is located, or the TXOP where a first PPDU carrying the first indication information is located; and making a communication decision based on the first indication information.

[0038] Optionally, making a communication decision based on the first indication information includes: determining whether to perform NPCA based on the first indication information, and / or determining the type of NPCA based on the first indication information.

[0039] Fourthly, a communication method is provided, which can be applied to a first station, for example, can be executed by the first station or by a component of the first station (e.g., a chip or circuit or chip system).

[0040] The method includes: receiving second indication information on a first primary channel, the second indication information indicating that the NPCA type of the first site is an NPCA based on the PPDU length; upon detecting a first PPDU and the first PPDU meeting the conditions for triggering an NPCA, switching from the first primary channel to a second primary channel, the second primary channel being a non-primary channel accessing the NPCA primary channel, the first PPDU being a PPDU sent by the second site or a site associated with the second site, the BSS to which the second site belongs and the BSS to which the first site belongs being each other's OBSS; and switching from the second primary channel to the first primary channel based on the end time of the first PPDU.

[0041] Based on the above scheme, the first station can enable NPCA based on PPDU length according to the second instruction information, so that the first station can switch back to the main channel in time to compete for the channel and avoid wasting the transmission resources of the main channel.

[0042] In conjunction with the fourth aspect, in some implementations, the first station is a first non-AP STA, and receives second indication information on the first main channel, including: receiving second indication information from the first AP on the first main channel, the second indication information being used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on PPDU length, wherein the non-AP STA associated with the first AP includes the first non-AP STA.

[0043] Based on the above scheme, the first AP can indicate the type of NPCA to be performed to its associated non-AP STA, so that the non-AP STA can select the appropriate NPCA scheme and improve resource utilization.

[0044] For example, the second indication information is carried in the beacon frame and / or probe response frame.

[0045] In conjunction with the fourth aspect, in some implementations, receiving the second indication information on the first main channel includes: receiving a first ICF from the second site on the first main channel, the first ICF including the second indication information, the second indication information being used to indicate that the type of NPCA performed by a site that is an OBSS with the BSS to which the second site belongs within the TXOP where the first ICF is located is an NPCA based on the PPDU length, wherein the first PPDU is a PPDU sent by the second site or a site associated with the second site within the TXOP where the first ICF is located, and the sites that are OBSS with the BSS to which the second site belongs include the first site.

[0046] Based on the above scheme, the second station can explicitly specify the type of NPCA to its OBSS station, enabling the first station to enable NPCA based on PPDU length. This allows the first station to switch back to the main channel in a timely manner to compete for channel resources, thus avoiding wasting the transmission resources of the main channel.

[0047] For example, the first ICF is a BSRP frame, and the second indication information is carried in the common information field or special user information field of the BSRP frame; or, the first ICF is a MU-RTS frame, and the second indication information is carried in the common information field or special user information field of the MU-RTS frame.

[0048] In conjunction with the fourth aspect, in some implementations, receiving the second indication information on the first main channel includes: receiving a first PPDU on the first main channel, wherein the preamble of the first PPDU includes the second indication information, the second indication information being used to indicate that the type of NPCA performed by a station that is an OBSS of the BSS to which the second station belongs within the TXOP where the first PPDU is located is an NPCA based on the length of the PPDU, wherein the station that is an OBSS of the BSS to which the second station belongs includes the first station.

[0049] Fifthly, a communication method is provided, the method comprising: generating second indication information, the second indication information being used to indicate that the NPCA type of a first station is an NPCA based on PPDU length; and transmitting the second indication information on a first main channel.

[0050] In conjunction with the fifth aspect, in some implementations, the method is applied to a first AP, the first site is a first non-APSTA, and the second indication information is used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the PPDU length, wherein the non-AP STA associated with the first AP includes the first non-AP STA.

[0051] In one example of this implementation, sending the second indication information on the first main channel includes: when it is determined that the second site has enabled DUO mode, sending the second indication information on the first main channel, wherein the BSS to which the second site belongs and the BSS to which the first AP belongs are each other's OBSS.

[0052] In another example of this implementation, the second indication information is sent on the first main channel, including: after determining that the first AP and the third AP have reached a Co-BF or Co-SR agreement, the second indication information is sent on the first main channel.

[0053] In conjunction with the fifth aspect, in some implementations, the method is applied to a second site, wherein sending second indication information on the first main channel includes: sending a first ICF on the first main channel, the first ICF including the second indication information, the second indication information being used to indicate that the type of NPCA performed by a site that is an OBSS with the BSS to which the second site belongs within the TXOP where the first ICF is located is an NPCA based on the PPDU length, wherein the site that is an OBSS with the BSS to which the second site belongs includes the first site.

[0054] In conjunction with the fifth aspect, in some implementations, the method is applied to a second station, wherein a first PPDU is transmitted on the first main channel, and the preamble of the first PPDU includes second indication information. The second indication information is used to indicate that the type of NPCA performed by a station that is an OBSS with the BSS to which the second station belongs within the TXOP of the first PPDU is an NPCA based on the length of the PPDU. The station that is an OBSS with the BSS to which the second station belongs includes the first station.

[0055] In a sixth aspect, a communication method is provided, which can be applied to a first station, for example, can be performed by the first station or by a component of the first station (e.g., a chip or circuit or chip system).

[0056] The method includes: receiving a first frame from a second site on a first primary channel, the first frame including an unavailability start time, the BSS to which the second site belongs and the BSS to which the first site belongs are each other's OBSS; if a first PPDU is detected in the TXOP where the first frame is located and the first PPDU satisfies the NPCA condition, switching from the first primary channel to a second primary channel, the second primary channel being the NPCA primary channel, and the first PPDU being a PPDU sent by the second site or a site associated with the second site; and switching from the second primary channel to the first primary channel based on the unavailability start time.

[0057] Based on the above scheme, the first station can switch back to the main channel from the NPCA main channel before the unavailability begins, thus utilizing the NPCA main channel more efficiently. Specifically, even if the second station shortens the TXOP due to DUO, the shortened portion still falls within the unavailability period of the OBSS station. Therefore, the main channel will still be occupied by the OBSS station before the unavailability begins, during which the first station can still perform NPCA. When switching back to the main channel at the start of the OBSS station's unavailability, the first station can promptly learn the status of the main channel, and can also compete for the main channel earlier if the OBSS TXOP terminates early.

[0058] For example, the first frame is a first ICR frame, the first ICR frame is a multi-site block acknowledgment frame, and the PPDU carrying the multi-site block acknowledgment frame is a non-HT PPDU.

[0059] In a seventh aspect, a communication method is provided, which can be applied to a first station, for example, can be performed by the first station or by a component of the first station (e.g., a chip or circuit or chip system).

[0060] The method includes: receiving a first frame from a second station on a first main channel, the first frame being used to query the unavailability information of the station associated with the second station, or the first frame being used to carry the unavailability information of the second station, wherein the BSS to which the second station belongs and the BSS to which the first station belongs are each other's OBSS; residing on the first main channel within the TXOP where the first frame is located, i.e., not performing NPCA.

[0061] Based on the above scheme, the first station can remain on the first main channel within the TXOP of the first frame. This avoids the problem of wasting main channel resources, and also avoids the problem of the first station wasting the main channel access opportunity due to switching to the NPCA main channel when the TXOP of the second station ends early.

[0062] Eighthly, a method of communication is provided, which can be applied to a first station, for example, can be performed by the first station or by a component of the first station (e.g., a chip or circuit or chip system).

[0063] The method includes: receiving a second frame from a second station on a first primary channel, the second frame being used to transmit control information in a first multi-AP cooperative process, the first multi-AP cooperative process being a coordinated spatial reuse (Co-SR, or CoSR, or COSR, or CSR, or co-SR) process or a coordinated beamforming (Co-BF, or CoBF, or COBF, or CBF, or co-BF) process, the second station participating in the first multi-AP cooperative process; if the first station does not participate in the first multi-AP cooperative process and detects that the first PPDU meets the conditions for triggering NPCA, switching from the first primary channel to the second primary channel, the second primary channel being the NPCA primary channel, the first PPDU being the downlink data PPDU in the first multi-AP cooperative process, the BSS to which the second station belongs and the BSS to which the first station belongs being each other's OBSS; or, if the first station participates in the first multi-AP cooperative process and detects the second frame or the first PPDU, residing on the first primary channel within the TXOP where the first multi-AP cooperative process is located, i.e., not performing NPCA.

[0064] Based on the above scheme, when the first station does not participate in the first multi-AP cooperation process being carried out by the OBSS station, the first station can start switching to the NPCA main channel only when it detects the downlink data PPDU of the OBSS station. When the first station participates in the first multi-AP cooperation process, the first station does not perform NPCA within the TXOP where the first multi-AP cooperation process is located. In other words, the OBSS control frame or downlink data PPDU in the multi-AP cooperation process in which the first station participates will not trigger the first station to switch to the NPCA main channel. The first station will only switch to the NPCA main channel when it detects the downlink data PPDU in the multi-AP cooperation process in which it does not participate. This can avoid the first station switching to the NPCA main channel at unnecessary times, thereby not only avoiding the transmission failure of the multi-AP cooperation process in which the first station participates, but also avoiding the waste of the transmission resources of the main channel.

[0065] For example, the second frame is a control frame preceding the downlink data PPDU in the first multi-AP collaboration process. For instance, the second frame is any of the following: ICF in the Co-BF process, ICR frame in the Co-BF process, ICF in the Co-SR process, or ICR frame in the Co-SR process.

[0066] In conjunction with the eighth aspect, in some implementations, the method further includes: switching from the second primary channel to the first primary channel based on the end time of the TXOP where the first multi-AP collaboration process is located; or, switching from the second primary channel to the first primary channel based on the end time of the first PPDU.

[0067] Based on the above scheme, the first station can switch back to the primary channel at the end of the TXOP in which the first multi-AP cooperation process occurs, thus avoiding frequent channel switching and saving overhead. Alternatively, the first station can switch back to the primary channel at the end of the first PPDU, allowing it to participate in primary channel contention in a timely manner and maximizing the utilization of primary channel resources.

[0068] In conjunction with aspect eight, in some implementations, the first PPDU includes N basic service set colors (BSS colors). These N BSS colors include the BSS colors of the basic service set BSSs to which the site participating in the first multi-AP collaboration process belongs. If the first site does not participate in the first multi-AP collaboration process, the N BSS colors and the BSS colors of the BSS to which the first site belongs are all different; or, if the first site does not participate in the first multi-AP collaboration process, the N BSS colors include the BSS colors of the BSS to which the first site belongs. N is an integer greater than or equal to 2.

[0069] Based on the above scheme, the first station can determine whether it participates in the first multi-AP collaboration process based on the BSS color included in the first PPDU. This enables the first station to determine the appropriate NPCA scheme, thereby allowing the first multi-AP collaboration process to proceed normally.

[0070] For example, switching from the first primary channel to the second primary channel includes: after detecting the universal signal field (U-SIG) of the first PPDU, starting the switch from the first primary channel to the second primary channel.

[0071] Based on the above scheme, since the U-SIG field and the fields preceding the U-SIG field contain the necessary information for determining whether to perform NPCA, for example, the L-SIG field preceding the U-SIG field includes the LENGTH field, and the U-SIG field includes the TXOP field and the BSS Color field, etc., switching can begin after the U-SIG field of the first PPDU is detected, thus obtaining the necessary information for determining whether to perform NPCA, which facilitates the first site to make a decision.

[0072] In conjunction with aspect eight, in some implementations, the first station is the first AP. Before receiving the second frame, the method further includes: after determining that the first AP and the third AP have reached a Co-BF or Co-SR agreement, sending second indication information on the first main channel. The second indication information is used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the PPDU length.

[0073] For example, if the first AP does not participate in the first multi-AP collaboration process, the third AP also does not participate in the first multi-AP collaboration process, but both the first AP and the third AP can participate in the second multi-AP collaboration process.

[0074] For example, when the first AP participates in the first multi-AP collaboration process, the third AP can be the second AP, that is, both the first AP and the third AP participate in the first multi-AP collaboration process.

[0075] In conjunction with aspect eight, in some implementations, the first station is a first non-AP STA. Before receiving the second frame, the method further includes: receiving second indication information from the first AP on the first main channel. The second indication information is used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the PPDU length. The non-AP STA associated with the first AP includes the first non-AP STA.

[0076] In a ninth aspect, a method of communication is provided, which can be applied to a first station, for example, can be performed by the first station or by a component of the first station (e.g., a chip or circuit or chip system).

[0077] The method includes: when a first PPDU is detected on the first primary channel and the first PPDU meets the conditions for triggering NPCA, switching from the first primary channel to the second primary channel, the second primary channel being the NPCA primary channel, the first PPDU being a PPDU sent by the second station or a station associated with the second station, the BSS to which the second station belongs and the BSS to which the first station belongs being each other's OBSS; and switching from the second primary channel to the first primary channel based on the end time of the first PPDU.

[0078] Based on the above scheme, the first station can always use NPCA based on PPDU length, which enables the first station to switch back to the main channel in a timely manner to compete for channel resources and avoid wasting the transmission resources of the main channel.

[0079] In conjunction with aspect nine, in some implementations, the first station is a first non-AP STA, and before detecting the first PPDU, the method further includes: receiving second indication information from the first AP on the first main channel, the second indication information being used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the PPDU length, wherein the non-AP STA associated with the first AP includes the first non-AP STA.

[0080] In conjunction with the ninth aspect, in some implementations, the first site is the first AP. Before detecting the first PPDU, the method further includes: if it is determined that the second site has enabled DUO mode, sending second indication information on the first main channel, the second indication information being used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the PPDU length.

[0081] In conjunction with the ninth aspect, in some implementations, the first station is the first AP. Before detecting the first PPDU, the method further includes: after determining that the first AP and the third AP have reached a Co-BF or Co-SR agreement, sending second indication information on the first main channel. The second indication information is used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the PPDU length.

[0082] In a tenth aspect, a communication device is provided. The device may be a first station or a component of the first station (e.g., a chip, circuit, or chip system). The device may have the functions described in the first aspect. For example, the device includes modules, units, or means that perform the operations described in the first aspect. These modules, units, or means may be implemented in software, hardware, or a combination of software and hardware.

[0083] Specifically, the device includes: a transceiver unit, configured to receive a first frame from a second station on a first main channel, the first frame being used to query unavailability information of a station associated with the second station, or the first frame being used to carry unavailability information of the second station, wherein the BSS to which the second station belongs and the BSS to which the first station belongs are each other's OBSS; a processing unit, configured to switch from the first main channel to the second main channel when a first PPDU is detected in the TXOP where the first frame is located and the first PPDU meets the conditions for triggering NPCA, the second main channel being the NPCA main channel, and the first PPDU being a PPDU sent by the second station or a station associated with the second station; the processing unit is further configured to switch from the second main channel to the first main channel based on the end time of the first PPDU.

[0084] Optionally, the processing unit is also configured to: perform opportunistic energy saving within the TXOP where the first ICF is located, based on the first instruction information.

[0085] In conjunction with aspect ten, in some implementations, the first station is a first non-AP STA. Before receiving the first frame, the transceiver unit is further configured to: receive second indication information from the first AP on the first main channel. The second indication information is used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the PPDU length, wherein the non-AP STA associated with the first AP includes the first non-AP STA.

[0086] In conjunction with aspect ten, in some implementations, the first station is the first AP. Before receiving the first frame, the transceiver unit is also used to: if it is determined that the second station has enabled DUO mode, send second indication information on the first main channel. The second indication information is used to indicate that the type of NPCA of the non-AP STA associated with the first AP is NPCA based on PPDU length.

[0087] In the eleventh aspect, a communication device is provided, which can be a second station or a component of the second station (e.g., a chip, circuit, or chip system). The device can have the functions described in the second aspect above. For example, the device includes a module, unit, or means corresponding to the operation involved in the second aspect above. The module, unit, or means can be implemented by software, hardware, or a combination of software and hardware.

[0088] Specifically, the device includes: a processing unit for generating first indication information, the first indication information being used to indicate whether there is a possibility of updating the first TXOP, the first TXOP being the TXOP where the first ICF carrying the first indication information is located, or the TXOP where the first PPDU carrying the first indication information is located; and a transceiver unit for transmitting the first indication information on the first main channel.

[0089] In the twelfth aspect, a communication device is provided, which may be a first station or a component of the first station (e.g., a chip, circuit, or chip system). The device may have the functions described in the third aspect above. For example, the device includes a module, unit, or means corresponding to the operation involved in the third aspect above. The module, unit, or means may be implemented by software, hardware, or a combination of software and hardware.

[0090] Specifically, the device includes: a transceiver unit, configured to receive first indication information on a first main channel, the first indication information indicating whether there is a possibility of updating a first TXOP, the first TXOP being either the TXOP containing a first ICF carrying the first indication information or the TXOP containing a first PPDU carrying the first indication information; and a processing unit, configured to make communication decisions based on the first indication information.

[0091] In a thirteenth aspect, a communication device is provided, which may be a first station or a component of the first station (e.g., a chip, circuit, or chip system). The device may have the functions described in the fourth aspect above. For example, the device includes a module, unit, or means corresponding to the operation involved in the fourth aspect above. The module, unit, or means may be implemented by software, hardware, or a combination of software and hardware.

[0092] Specifically, the device includes: a transceiver unit, configured to receive second indication information on a first main channel, the second indication information indicating that the NPCA type of the first site is an NPCA based on the PPDU length; a processing unit, configured to switch from the first main channel to a second main channel when a first PPDU is detected and the first PPDU meets the conditions for triggering an NPCA, the second main channel being a non-main channel access NPCA main channel, the first PPDU being a PPDU sent by the second site or a site associated with the second site, the BSS to which the second site belongs and the BSS to which the first site belongs being OBSSs for each other; the processing unit is further configured to switch from the second main channel to the first main channel based on the end time of the first PPDU.

[0093] In a fourteenth aspect, a communication device is provided. The device may be a first access point (AP) or a second station, or a component (e.g., a chip, circuit, or chip system) of the first AP or the second station. The device may have the functions described in the fifth aspect above. For example, the device includes a module, unit, or means for performing the operations described in the fifth aspect above. The module, unit, or means may be implemented by software, by hardware, or by a combination of software and hardware.

[0094] Specifically, the device includes: a processing unit for generating second indication information, the second indication information indicating that the NPCA type of the first station is an NPCA based on PPDU length; and a transceiver unit for transmitting the second indication information on the first main channel.

[0095] In the fifteenth aspect, a communication device is provided, which may be a first station or a component of the first station (e.g., a chip, circuit, or chip system). The device may have the functions described in the sixth aspect above. For example, the device includes a module, unit, or means for performing the operations described in the sixth aspect above. The module, unit, or means may be implemented by software, hardware, or a combination of software and hardware.

[0096] Specifically, the device includes: a transceiver unit, configured to receive a first frame from a second station on a first primary channel, the first frame including an unavailability start time, and the BSS to which the second station belongs and the BSS to which the first station belongs are each other's OBSS; a processing unit, configured to switch from the first primary channel to a second primary channel when a first PPDU is detected in the TXOP where the first frame is located and the first PPDU meets the conditions of NPCA, the second primary channel being the NPCA primary channel, and the first PPDU being a PPDU sent by the second station or a station associated with the second station; the processing unit is further configured to: switch from the second primary channel to the first primary channel based on the unavailability start time.

[0097] In a sixteenth aspect, a communication device is provided, which may be a first station or a component of the first station (e.g., a chip, circuit, or chip system). The device may have the functions described in the seventh aspect above. For example, the device includes a module, unit, or means for performing the operations described in the seventh aspect above. The module, unit, or means may be implemented by software, hardware, or a combination of software and hardware.

[0098] Specifically, the device includes: a transceiver unit, configured to receive a first frame from a second station on a first main channel, the first frame being used to query unavailability information of a station associated with the second station, or the first frame being used to carry unavailability information of the second station, wherein the BSS to which the second station belongs and the BSS to which the first station belongs are each other's OBSS; and a processing unit, configured to camp on the first main channel before receiving an end indication of the TXOP containing the first frame; or configured to camp on the first main channel before the countdown of the NAV timer set according to the first frame ends.

[0099] In a seventeenth aspect, a communication device is provided, which may be a first station or a component of the first station (e.g., a chip, circuit, or chip system). The device may have the functions described in the eighth aspect above. For example, the device includes a module, unit, or means for performing the operations described in the eighth aspect above. The module, unit, or means may be implemented by software, hardware, or a combination of software and hardware.

[0100] Specifically, the device includes: a transceiver unit, configured to receive a second frame from a second station on a first primary channel, the second frame being used to transmit control information in a first multi-AP cooperation process, the first multi-AP cooperation process being a Co-SR process or a Co-BF process, and the second station participating in the first multi-AP cooperation process; a processing unit, configured to switch from the first primary channel to the second primary channel when the first station does not participate in the first multi-AP cooperation process and detects that the first PPDU meets the conditions for triggering NPCA, the second primary channel being the NPCA primary channel, the first PPDU being a downlink data PPDU in the first multi-AP cooperation process, and the BSS to which the second station belongs and the BSS to which the first station belongs being each other's OBSS; or, the processing unit is configured to: when the first station participates in the first multi-AP cooperation process and detects the second frame or the first PPDU, reside on the first primary channel within the TXOP where the first multi-AP cooperation process is located.

[0101] In conjunction with aspect seventeen, in some implementations, the processing unit is also used to: switch from the second primary channel to the first primary channel based on the end time of the TXOP in which the first multi-AP cooperative process is located; or, switch from the second primary channel to the first primary channel based on the end time of the first PPDU.

[0102] In conjunction with aspect seventeen, in some implementations, the first station is the first AP. Before receiving the second frame, the transceiver unit is also used to: after determining that the first AP and the third AP have reached a Co-BF or Co-SR agreement, send second indication information on the first main channel. The second indication information is used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the PPDU length.

[0103] In conjunction with aspect seventeen, in some implementations, the first station is a first non-AP STA, and before receiving the second frame, the transceiver unit is further configured to: receive second indication information from the first AP on the first main channel, the second indication information being used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on PPDU length, and the non-AP STA associated with the first AP includes the first non-AP STA.

[0104] In the eighteenth aspect, a communication device is provided, which may be a first station or a component of the first station (e.g., a chip, circuit, or chip system). The device may have the functions described in the ninth aspect above. For example, the device includes a module, unit, or means corresponding to the operation described in the ninth aspect above. The module, unit, or means may be implemented by software, hardware, or a combination of software and hardware.

[0105] Specifically, the device includes: a processing unit, configured to switch from the first main channel to the second main channel when the first PPDU is detected on the first main channel and the first PPDU meets the conditions for triggering NPCA, wherein the second main channel is the NPCA main channel, the first PPDU is a PPDU sent by the second station or a station associated with the second station, and the BSS to which the second station belongs and the BSS to which the first station belongs are each other's OBSS; the processing unit is further configured to switch from the second main channel to the first main channel based on the end time of the first PPDU.

[0106] In conjunction with aspect 18, in some implementations, the first station is a first non-AP STA, and the apparatus further includes: a transceiver unit for receiving second indication information from the first AP on a first main channel, the second indication information indicating that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on PPDU length, wherein the non-AP STA associated with the first AP includes the first non-AP STA.

[0107] In conjunction with aspect 18, in some implementations, the first site is a first AP, and the apparatus further includes: a transceiver unit, configured to transmit second indication information on a first main channel when it is determined that the second site has enabled DUO mode, the second indication information being used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on PPDU length.

[0108] In conjunction with aspect 18, in some implementations, the first station is a first AP, and the apparatus further includes: a transceiver unit, configured to transmit second indication information on a first main channel after determining that the first AP and the third AP have reached a Co-BF or Co-SR agreement, the second indication information being used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the PPDU length.

[0109] It should be understood that for any parts not described in detail in aspects 10 to 18, please refer to aspects 1 to 9, which will not be repeated here.

[0110] In a nineteenth aspect, a communication apparatus is provided, comprising: a memory for storing a program; and at least one processor for executing the computer program or instructions stored in the memory to perform the method provided in any of the foregoing aspects or their implementations.

[0111] In one implementation, the device is either a first station or a second station.

[0112] In another implementation, the device is a chip, chip system, or circuit for use in a first or second site.

[0113] In a twentieth aspect, a communication apparatus is provided, comprising: at least one processor and a communication interface, the at least one processor being configured to obtain a computer program or instructions stored in a memory via the communication interface to execute the method provided in any of the foregoing aspects or their implementations. The communication interface may be implemented in hardware or software.

[0114] In one implementation, the device also includes a memory.

[0115] In a twentieth aspect, a processor is provided for performing the method provided in any of the foregoing aspects.

[0116] Unless otherwise specified, or if it does not contradict its actual function or internal logic in the relevant description, the transmission and acquisition / reception operations involved in the processor can be understood as processor output and reception, input and other operations, or as transmission and reception operations performed by radio frequency circuits and antennas. This application does not limit them in this regard.

[0117] In a twenty-second aspect, a computer-readable storage medium is provided that stores program code for execution by a device, the program code including methods for performing any of the above aspects or implementations thereof.

[0118] In a twenty-third aspect, a computer program product including instructions is provided, which, when run on a computer, causes the computer to perform the method provided in any of the foregoing aspects or their implementations.

[0119] In a twenty-fourth aspect, a chip is provided, comprising a processor and a communication interface. The processor reads instructions stored in a memory through the communication interface and executes the method provided in any of the above aspects or their implementations. The communication interface can be implemented in hardware or software.

[0120] Optionally, as one implementation, the chip also includes a memory storing computer programs or instructions, and a processor for executing the computer programs or instructions stored in the memory. When the computer programs or instructions are executed, the processor is used to perform the methods provided by any of the above aspects or their implementations.

[0121] When the method provided in this application is executed by a chip, this application does not limit the specific number of chips implementing the method. For example, it can be executed by one chip, or by two or more chips. Furthermore, when the number of chips implementing the method is two or more, the chip manufacturers are not limited; they can be from the same manufacturer or different manufacturers.

[0122] In a twenty-fifth aspect, a computer program is provided that, when run on a computer, causes the methods provided by any of the foregoing aspects or their implementations to be executed.

[0123] In a twentieth aspect, a communication system is provided, which includes the aforementioned first site and second site.

[0124] It should be understood that the beneficial effects of aspects 10 to 26 and any of their implementations can be referenced from aspects 1 to 9 and any of their implementations. Attached Figure Description

[0125] Figure 1 This is a schematic diagram of a network architecture applicable to embodiments of this application.

[0126] Figure 2 This is a schematic diagram of the NPCA process.

[0127] Figure 3 This is a schematic diagram of the Co-BF transmission phase.

[0128] Figure 4 This is a schematic diagram of the Co-BF measurement process.

[0129] Figure 5 This is a schematic diagram of the Co-SR transmission phase.

[0130] Figure 6 This is a diagram illustrating how TXOP is shortened due to unavailable information.

[0131] Figure 7 This is a schematic flowchart of a communication method 700 provided in this application.

[0132] Figure 8 This is a schematic diagram of the NPCA triggering mechanism provided in this application.

[0133] Figure 9 This is a schematic diagram of the public information fields and special user information fields provided in the embodiments of this application.

[0134] Figure 10 This is a schematic flowchart of a communication method 1000 provided in this application.

[0135] Figure 11 This is another schematic diagram of the NPCA triggering mechanism provided in this application.

[0136] Figure 12 This is another schematic diagram of the NPCA triggering mechanism provided in this application.

[0137] Figure 13 and Figure 14 This is a schematic diagram of the communication device provided in this application. Detailed Implementation

[0138] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0139] The embodiments of this application can be applied to WLAN, for example, supporting IEEE 802.11 related standards (or protocols), such as 802.11a / b / g standards, 802.11n standards, 802.11ac standards, 802.11ax standards (i.e. Wi-Fi 6, also known as the high efficient (HE) standard), 802.11be standards (i.e. Wi-Fi 7, also known as the extremely high throughput (EHT) standard), 802.11bn standards (i.e. Wi-Fi 8, also known as the ultra high reliability (UHR) standard) or next-generation Wi-Fi 8 standards, and also including 802.11ad, 802.11ay standards, etc. The embodiments of this application can also be applied to wireless local area network systems that support integrated millimeter wave (IMMW), wireless local area network systems that support ultra-wideband (UWB) such as the 802.15 series standards, sensing systems such as the 802.11bf series standards, or wireless positioning such as 802.11az. This application can also support standards such as spark link and near link.

[0140] It should be understood that standards and protocols are interchangeable in this application. Unless otherwise specified, the IEEE 802.11 standard is referred to as the 802.11 standard.

[0141] The technical solutions of this application embodiment can also be applied to various communication systems, such as: 5th generation (5G) systems or new radio (NR), future communication systems, Internet of Things (IoT) networks or vehicle-to-everything (V2X) networks, etc.

[0142] The communication systems described above that are applicable to this application are merely illustrative examples, and the communication systems applicable to this application are not limited to these. They will be uniformly described here and will not be repeated below.

[0143] A WLAN can include multiple basic service sets (BSS), and the network nodes in a BSS are collectively referred to as stations (STAs). BSS is a fundamental module of IEEE 802.11 local area networks. Depending on the topology, function, etc., BSS can be divided into infrastructure BSS and independent BSS, etc.

[0144] In a structured BSS, one site is used to access the distribution system (DS). This site is called an Access Point (AP) site, or simply AP. Other sites are called non-access point (NAP) sites, or simply non-AP STAs. Non-AP STAs need to access the DS through an AP. Therefore, STAs in a structured BSS can be specifically divided into APs and non-AP STAs. Each BSS can include one AP and multiple non-AP STAs associated with that AP. Within a BSS, data can be transmitted between the AP and each non-AP STA. A BSS can also be understood as a cell. STAs in an independent BSS are equal; there is no distinction between APs and non-AP STAs, and data can be transmitted between STAs. Unless otherwise specified, this application refers to a structured BSS, and a site can be either an AP or a non-AP STA.

[0145] The AP in this application embodiment can also be called a wireless access point or hotspot. An AP is an access point for mobile users to access a wired network, mainly deployed in homes, buildings, and campuses, with a typical coverage radius of tens to hundreds of meters. Of course, it can also be deployed outdoors. An AP acts as a bridge connecting wired and wireless networks, its main function being to connect various wireless network clients together and then connect the wireless network to the Ethernet. Specifically, the AP can be a device supporting the 802.11 series standards, such as 802.11ac, 802.11ax, 802.11be, 802.11bn, or later versions of one or more WLAN standards.

[0146] In this application embodiment, the non-AP STA can be a wireless communication chip, a wireless sensor, or a wireless communication terminal. For example, it can be a mobile phone supporting WiFi communication, a tablet computer supporting WiFi communication, a set-top box supporting WiFi communication, a smart TV supporting WiFi communication, a smart wearable device supporting WiFi communication, an in-vehicle communication device supporting WiFi communication, or a computer supporting WiFi communication. The non-AP STA can support the 802.11 series standards; for example, a non-AP STA can be a device that supports one or more WLAN standards such as 802.11ac, 802.11ax, 802.11be, 802.11bn, or later versions.

[0147] In this embodiment, the non-AP STA or AP includes a hardware layer, an operating system layer running on top of the hardware layer, and an application layer running on top of the operating system layer. The hardware layer includes hardware such as a central processing unit (CPU), a memory management unit (MMU), and memory (also called main memory). The operating system can be any one or more computer operating systems that implement business processing through processes, such as Linux, Unix, Android, iOS, or Windows. The application layer includes applications such as browsers, address books, word processing software, and instant messaging software. Furthermore, this embodiment does not specifically limit the structure of the execution entity of the method provided in this embodiment, as long as it can communicate according to the method provided in this embodiment by running a program that records the code of the method provided in this embodiment. For example, the execution entity of the method provided in this embodiment can be a non-AP STA or AP, or a functional module in a non-AP STA or AP that can call and execute a program.

[0148] Furthermore, various aspects or features of this application can be implemented as methods, apparatus, or articles of manufacture using standard programming and / or engineering techniques. The term "article of manufacture" as used herein encompasses a computer program accessible from any computer-readable device, carrier, or medium. For example, computer-readable media may include, but are not limited to: magnetic storage devices (e.g., hard disks, floppy disks, or magnetic tapes), optical discs (e.g., compact discs (CDs), digital versatile discs (DVDs), etc.), smart cards, and flash memory devices (e.g., erasable programmable read-only memory (EPROMs), cards, sticks, or key drives, etc.). Additionally, the various storage media described herein may represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media capable of storing, containing, and / or carrying instructions and / or data.

[0149] Figure 1 This is a schematic diagram of the network architecture of a wireless local area network applicable to embodiments of this application. Figure 1 include Figure 1 (a) and Figure 1 (b)

[0150] like Figure 1 As shown in (a), a BSS may include an AP and one or more non-AP STAs associated with that AP. A wireless LAN network architecture may also include multiple BSSs, for example, Figure 1As shown in (b), BSS#1, BSS#2, and BSS#3 are the three structural BSSs for accessing the DS. AP#1, AP#2, and AP#3 are used to access the DS, and they can also communicate with each other. Non-AP STA11, non-AP STA12, and non-AP STA13 in BSS#1 access the DS through AP#1; non-AP STA21, non-AP STA22, and non-AP STA23 in BSS#2 access the DS through AP#2; and non-AP STA31 and non-AP STA32 in BSS#3 access the DS through AP#3. BSS#1 and BSS#2 partially overlap, meaning these two BSSs form an overlapping basic service set (OBSS). Non-AP STA11, non-AP STA12, and non-AP STA23 represent the overlapping portions of the two BSSs. There is no overlap between BSS#3 and BSS#1, and no overlap between BSS#3 and BSS#2. Non-AP STAs can communicate with each other via AP.

[0151] In this application, OBSS refers to a BSS with overlapping coverage areas and using overlapping channels. Specifically, to reduce signal coverage dead zones, APs may be deployed with overlapping coverage areas. However, due to limited spectrum, the same channel may be reused by multiple BSSs. Thus, there may be situations where BSSs with overlapping coverage areas use overlapping channels. Therefore, OBSSs can communicate with each other, but they can also interfere with each other. An OBSS site refers to a site within a BSS that is an OBSS of the site's own BSS. For example, in... Figure 1 In (b), BSS#1 and BSS#2 are each other's OBSS. Therefore, for any one of AP#1, non-AP STA11, non-AP STA12, and non-AP STA13, any one of AP#2, non-AP STA21, non-AP STA22, and non-AP STA23 is an OBSS site. For any one of AP#2, non-AP STA21, non-AP STA22, and non-AP STA23, any one of AP#1, non-AP STA11, non-AP STA12, and non-AP STA13 is an OBSS site.

[0152] It should be understood that Figure 1This is merely an example and should not limit the network architecture of the wireless local area network to which this application applies. For example, the network architecture may include more BSSs, each BSS may include more non-AP STAs, or some BSSs may not include APs. Areas where multiple BSSs overlap may also include more non-AP STAs, etc., which are not limited in the embodiments of this application.

[0153] To facilitate understanding of this application, we will first briefly introduce some terms that may be involved in this application.

[0154] 1. NPCA In the 802.11 protocol, an Access Point (AP) can operate on frequency bands such as 2.4 GHz, 5 GHz, and 6 GHz. An AP occupies a specific channel within a particular frequency band, such as an 80 MHz channel in the 5 GHz band, and communicates with non-AP STAs on these channels. With the development of the 802.11 protocol, the channel bandwidth that an AP can occupy has increased significantly. In 802.11be, the maximum channel bandwidth available to an AP can reach 320 MHz. These large-bandwidth channels are logically divided into 20 MHz sub-channels; for example, an 80 MHz channel can be divided into four 20 MHz sub-channels. A BSS's 20 MHz sub-channels can be classified as primary channels or non-primary channels. The specific sub-channel selected as the primary channel is determined by the BSS configuration. Non-primary channels within the AP's operating bandwidth can also be called secondary channels or slave channels. Among them, "channel bandwidth that AP can occupy" can be understood as the bandwidth that AP can support or the bandwidth that AP can theoretically occupy. "AP operating bandwidth" can be understood as the AP's working bandwidth, the bandwidth of AP's actual communication, or the bandwidth that AP actually occupies. AP operating bandwidth is part or all of the channel bandwidth that AP can occupy.

[0155] Unless otherwise specified in this application, the term "main channel" refers to the main 20MHz sub-channel, and "non-main channel" refers to any 20MHz sub-channel other than the main 20MHz sub-channel. It should be understood that in addition to the main 20MHz sub-channel, there are also main 40MHz channels, main 80MHz channels, etc., all of which include the main 20MHz sub-channel; conversely, "secondary 40MHz channel," "secondary 80MHz channel," etc., indicate portions that do not include the main 20MHz sub-channel.

[0156] When an AP communicates with a non-AP STA, to avoid collisions, the station (e.g., AP or non-AP STA) needs to perform carrier sense to ensure the channel is idle. Specifically, the station can perform energy detection (ED) on all sub-channels and preamble detection (PD) on the main channel. ED detects the strength of the radio signal on the sub-channel; if a strong radio signal is detected, the sub-channel is considered busy. PD detects whether there is a PPDU on the main channel and decodes the detected PPDU to extract relevant information. The information extracted from the PPDU may include a duration field, indicating how much time is needed after this PPDU to complete frame interaction. Based on the duration field decoded by PD on the main channel, the station can set a corresponding NAV timer. The NAV timer ends at the end time indicated by the duration field. Before the NAV timer ends, the station must not compete for the channel, thus protecting the TXOP of other stations (such as the station sending the aforementioned PPDU). Due to the high complexity of PD, the protocol only requires PD to be performed on the primary channel, which is called "primary channel access". ED and PD can be collectively referred to as clear channel assessment (CCA).

[0157] The primary channel access mechanism is relatively simple to implement and has met the needs of most scenarios for a long time. However, with the development of the 802.11 protocol, the bandwidth available to sites has increased significantly. When the primary channel is busy and the non-primary channels are idle, primary channel access will determine that the entire channel cannot be used, thus wasting the resources of the non-primary channels. In this way, although the operating bandwidth of the site increases, it cannot be used effectively.

[0158] To address this, 802.11bn introduced the "Non-Main Channel Access" mechanism. Specifically, when the main channel is busy, a site can switch to a sub-channel of a non-main channel for PD (Power-On-Demand) communication, thereby improving channel utilization. For example, if an AP (Access Point) with an operating bandwidth of 160MHz detects an 80MHz PPDU (Power-On-Demand DU) while performing PD on the main channel, the AP can switch to a 20MHz sub-channel of an idle 80MHz channel for PD. The sub-channel used for PD is called the NPCA (National Standard Access Channel) primary channel, also known as a temporary primary channel or NPCA anchor channel. NPCA applications are generally based on BSS (Best-Side System). If an AP and a non-AP STA within a BSS (e.g., BSS1) detect an OBSS (On-Board Access Stream) transmission on the main channel, such as a TXOP (Transmission of a TXOP) on BSS2, then both the AP and non-AP STA in BSS1 will switch to the NPCA primary channel for communication. It should be noted that if the detected transmission is within this BSS, such as TXOP of BSS1, it means that the AP within this BSS is communicating, so the site will not perform NPCA jump.

[0159] Figure 2 This is a schematic diagram of NPCA. AP1 has an operating bandwidth of 160MHz, including the main 80MHz channel (i.e., Figure 2 The “P80” in the middle and the sub-80MHz channel (i.e. Figure 2 The “S80” in the text refers to the setting of the NPCA main channel on a sub-channel of the next 80MHz (in the context of the NPCA main channel). Figure 2 (Indicated by "NPCA P20"). When AP1 is on the main channel (in... Figure 2 When the channel is occupied by OBSS (indicated by "P20"), it does not need to back off on the main channel. Instead, it jumps to the NPCA main channel to compete for the channel, so that it can use the channel that is not occupied by OBSS for transmission.

[0160] 2. TXOP A TXOP (Transmission Request Opportunity) refers to a time interval (or period) during which a station can initiate a frame interaction sequence. It is defined by a start time and a maximum duration. A station can acquire a TXOP through contention when the channel is idle. Within this TXOP, a station can transmit, and multiple PPDUs (Programmable Component Distributed Units) can be transmitted within a single TXOP. The station that acquires the TXOP is called the TXOP holder, and the station transmitting within the TXOP is called the TXOP responder. The length of the TXOP is the length of the first PPDU plus the length indicated by the Duration field of the first PPDU. Other stations do not compete for the channel before the end of the PPDU and before the NAV (Network Validation) timer expires, thus protecting the station's TXOP. If the station's TXOP ends prematurely, even if the channel is idle, other stations must wait until their original NAV timer countdown ends before they can begin competing for the channel. To ensure that other stations can compete for the channel in a timely manner, the station can reset the NAV timers of other stations to 0 by certain methods after the TXOP ends prematurely. For example, one way to instruct other sites to reset NAV is for the site to send a contention-free end (CF-End) frame.

[0161] It should be understood that the lengths of PPDU and TXOP mentioned above refer to time lengths, i.e., duration.

[0162] 3. In-device coexistence (IDC) and unavailability information. In the 802.11 protocol, IDC (Internet Data Center) addresses the interference issues caused by the coexistence of multiple wireless technologies within a site (including access points (APs) or non-AP STAs). Specifically, because the IEEE 802.11 protocol (or Wi-Fi) and other wireless technologies (such as Bluetooth) may use overlapping channels, different technologies can interfere with each other during transmission. For example, Bluetooth may interfere with Wi-Fi, preventing them from transmitting normally. To avoid interference from other wireless technologies and to reduce interference from other wireless technologies when using the 802.11 protocol, the site needs to avoid transmissions by other wireless technologies (i.e., during IDC). This makes the site unavailable during this period, unable to transmit using the 802.11 protocol normally; in other words, the site will have unavailable information due to IDC.

[0163] For example, an AP or non-AP STA may be completely or partially unavailable during IDC, depending on the channels occupied by other wireless technologies. Alternatively, IDC-induced unavailability can manifest in various ways, such as a device being unable to transmit for a period of time, a reduction in available bandwidth, or a decrease in the number of available spatial streams (NSS), etc.

[0164] IDCs (Internet Data Centers) can be categorized into periodic and non-periodic types. Generally, periodic IDCs appear at regular intervals and last for a defined period, making them relatively easy to predict in advance. Non-periodic IDCs, on the other hand, are often bursty, with uncertain start times and durations, making them difficult to predict. Furthermore, IDCs can be classified as long-term or short-term; periodic IDCs are generally long-term, while non-periodic IDCs are generally short-term. Because IDCs can cause equipment unavailability, sites can inform other sites of this unavailability in advance, thus avoiding unnecessary transmission and resource waste.

[0165] When notifying users of unavailability information, different methods may be used considering the differences between periodic and non-periodic IDCs. The operation mode that supports AP or non-AP STA notifying users of periodic unavailability information can be called the periodic unavailability operation (PUO) mode. The operation mode that supports AP or non-AP STA notifying users of non-periodic or dynamic unavailability information can be called the DUO mode. PUO mode can also be referred to as the PUO mechanism, and DUO mode can also be referred to as the DUO mechanism.

[0166] For example, IDC mainly appears on the non-AP STA side because non-AP STAs generally support multiple wireless technologies, but it may also appear on the AP side, especially in the case of mobile APs.

[0167] It should be noted that IDC can also be called coexistence (CoEx) or other names, and this application does not impose any restrictions on this. For ease of description, this document uses IDC as an example. In addition, the unavailability information caused by IDC mentioned above can also be called IDC information, PUO information, or DUO information, etc.

[0168] 4. Co-BF In the IEEE 802.11bn protocol, a Multi-AP Coordination (MAPC) framework was proposed to further improve air interface transmission efficiency. Under the MAPC framework, APs can utilize air interface resources more efficiently for transmission through various cooperative mechanisms.

[0169] Co-BF is a multi-AP cooperative mechanism in which multiple APs with multiple antennas participating in Co-BF adjust the direction of signal transmission based on channel state information (CSI) to achieve better throughput and reliability, and reduce latency. Specifically, two APs participating in Co-BF (AP1 and AP2) can utilize the CSI between their own AP and another AP's non-AP STA (e.g., between AP1 and non-AP STA2, where non-AP STA2 is associated with AP2) to simultaneously transmit with their respective associated non-AP STAs and minimize interference to OBSS sites.

[0170] To determine the CSI between the AP and the non-AP STA, a Co-BF measurement (sounding) process is required before data transmission. The stage where the AP participating in Co-BF obtains the CSI through sounding can be called the Co-BF sounding stage, while the stage of using Co-BF for data transmission can be called the Co-BF transmission stage.

[0171] In IEEE 802.11bn, the number of APs participating in Co-BF transmission is limited to two. During Co-BF transmission, one AP obtains a TXOP and initiates the Co-BF transmission to the other AP. The AP initiating the Co-BF transmission is called the sharing AP, and the other AP is called the shared AP. This application uses one shared AP as an example, but it does not limit the number of shared APs. Furthermore, in this application, the sharing AP can also be called a shared AP, master AP, initiating AP, coordinating AP, inviting AP, etc. Similarly, the shared AP can be called a shared AP, slave AP, responding AP, coordinated AP, invited AP, etc.

[0172] Figure 3This is a schematic diagram of the Co-BF transmission phase, such as... Figure 3 As shown, AP1 is a sharing AP, and AP2 is a shared AP. The BSS of AP1 and the BSS of AP2 are each other's OBSS. The two APs can transmit downlink data PPDUs simultaneously without interference. Specifically, after AP1 obtains the TXOP, it initiates a Co-BF transmission to AP2 by sending a Co-BF invite frame. AP2 responds with a Co-BF response frame, indicating its participation in the Co-BF transmission and carrying the parameter information required for the Co-BF transmission. After the Co-BF Invite and Co-BF Response frame exchanges, if necessary, the two APs sequentially exchange ICF and ICR frames with their respective non-AP STAs. The functions of the ICF and ICR frames include switching enhanced multi-link single-radio (EMLSR) STAs from listening mode to a state where they can exchange frames, and switching dynamic power save (DPS) STAs from low-capability mode to high-capability mode, etc. Figure 3 In the diagram, ICF1 and ICR1 represent the ICF and ICR between the sharing AP and non-AP STA1, while ICF2 and ICR2 represent the ICF and ICR between the shared AP and non-AP STA2. Following this, the sharing AP sends a Co-BF trigger frame, initiating Co-BF transmission of downlink (DL) PPDUs (i.e., Co-BF data PPDUs, or simply data PPDUs). The data PPDUs transmitted by different APs must be aligned (i.e., start and end simultaneously), and the preambles of the data PPDUs sent by AP1 and AP2 must be identical. Furthermore, the U-SIG field in each preamble includes the BSS colors of both APs. After receiving the data PPDUs from their respective APs, the non-AP STAs associated with the two APs reply with a block acknowledgement (BA) frame to confirm receipt. Figure 3 Taking two non-AP STAs simultaneously replying to the associated AP as an example, the two non-AP STAs can also reply to the BA in sequence.

[0173] It should be understood that there may be other forms of frame interaction procedures during the Co-BF transmission phase, but they are basically the same as... Figure 3Similarly, this will include frame interaction between the two APs, frame interaction between each AP and its respective non-AP STA via ICF or ICR, aligned DLPPDU transmission, and non-AP STA replying to the associated AP via BA. This application does not limit the frame interaction procedure during the Co-BF transmission phase.

[0174] Furthermore, in this application, ICR frames may be abbreviated as ICR, and unless otherwise specified, ICR refers to ICR frames.

[0175] Figure 4 This is a schematic diagram of the Co-BF measurement process, as shown below. Figure 4 As shown, there are two measurement procedures for Co-BF: one is sequential sounding, such as... Figure 4 As shown in (a), another type is joint sounding, such as Figure 4 As shown in (b), through measurement, AP1 can obtain the CSI between AP1 and non-AP STA1, and the CSI between AP1 and non-AP STA2; AP2 can obtain the CSI between AP2 and non-AP STA2, and the CSI between AP2 and non-AP STA1. The two measurement procedures are largely similar, the main difference being that when measuring each non-AP STA, sequential measurements involve AP1 and AP2 sending null data PPDU (NDP) frames in turn, while joint measurements involve both APs sending NDPs simultaneously. In both measurement procedures, there will be interaction between AP1 and AP2 using sounding invite and sounding response frames, as well as interaction between each AP and its respective non-AP STA using ICF and ICR frames, which function similarly to the corresponding frames in the Co-BF transmission procedure. Figure 4 In this context, NDPA stands for null data PPDU announcement frame; BFRP stands for beamforming report poll frame. Figure 4 The CSI in the text can represent a frame carrying CSI information, such as an EHT compressed beamforming / channel quality indication (CQI) frame or a UHR compressed beamforming / channel quality indication frame.

[0176] 5. Co-SR Co-SR is another multi-AP cooperative mechanism introduced in IEEE 802.11bn. Multiple APs participating in Co-SR cooperate to control transmit power, thereby reducing interference to OBSS sites and more effectively utilizing the air interface for parallel transmission with their respective non-AP STAs. In other words, by limiting transmission power, APs ensure that the signal strength received by other APs and their non-AP STAs remains within a range that will not cause interference. Through cooperation, APs can share relevant transmit power control information with each other.

[0177] The number of APs participating in Co-SR transmission can be two or more; this application uses two as an example for illustration. Similar to Co-BF, during Co-SR transmission, one AP obtains a TXOP and initiates Co-SR transmission to other APs. In this case, the AP initiating the Co-SR transmission can be called the sharing AP, while the other APs are called shared APs.

[0178] Figure 5 This is a schematic diagram of the Co-SR transmission phase. Figure 5 In this configuration, AP1 is a sharing AP, and AP2 is a shared AP. The BSS belonging to AP1 and the BSS belonging to AP2 are each other's OBSS. The two APs can transmit downlink data PPDUs simultaneously without interference. The frame exchange process for Co-SR transmission is similar to that of Co-BF transmission; the function of each frame will not be elaborated here. The main difference between Co-SR and Co-BF lies in the transmission method of DL PPDUs.

[0179] As can be seen from the above, there are a variety of different mechanisms in the WLAN protocol. When the NPCA mechanism coexists with other mechanisms (such as the DUO mechanism or the multi-AP cooperation mechanism), it may lead to problems such as resource waste and transmission failure.

[0180] For example, when the NPCA and DUO mechanisms coexist, if a station is triggered by an NPCA frame sent by an OBSS station to inquire about or inform of unavailability, it may lead to a decrease in the station's channel utilization efficiency. This unavailability information can be understood as the unavailability information in the DUO mechanism, i.e., DUO information.

[0181] Specifically, when an OBSS site (such as non-AP STA 2) enables DUO mode, its associated AP (such as AP 2) needs to send an ICF (Initial Communication Message) querying for unavailability information before initiating data transmission. Upon receiving the ICF, non-AP STA 2 replies with an ICR (Initial Communication Message), indicating its own unavailability information, such as the unavailability target start time and unavailability duration. The ICF sent by AP2 serves as the start of frame interaction; this ICF queries the non-AP STA for unavailability information and is a BSRP (Balanced Short Frame Retrieval Message) frame. After receiving the ICF from AP2, non-AP STA 2 needs to reply with an ICR, carrying unavailability information; this ICR can be a Multi-STA BA (Balanced Short Frame Retrieval Message) frame. Alternatively, if the non-AP STA is a TXOP holder, it can also proactively send an ICF to the AP, carrying its own unavailability information; in this case, the ICF can also be a BSRP frame.

[0182] When AP 2, acting as the TXOP holder, learns of the unavailability of non-AP STA 2, and if non-AP STA 2 will be unavailable during the TXOP period, in order to avoid transmission failure between AP 2 and non-AP STA 2, AP 2 may choose to shorten the TXOP, only transmitting with non-AP STA 2 before the start of non-AP STA 2's unavailability, and sending a CF-End to prematurely end the TXOP after the transmission is completed; alternatively, AP 2 can directly terminate the TXOP after the interaction of ICF and ICR. Since AP 2 operates on the primary channel (e.g., the primary 20MHz channel, denoted as P20), for this BSS site (e.g., AP 1 or non-APSTA 1), the ICF or ICR on the primary channel will trigger AP 1 or non-AP STA 1 to perform NPCA. According to the current NPCA rules, both AP 1 and non-AP STA 1 switch to the NPCA primary channel (e.g., the NPCA primary 20MHz channel, denoted as NPCA P20) after the ICR, and switch back to the primary channel from the NPCA primary channel before the end of AP 2's initial TXOP (i.e., shortening the previous TXOP or not terminating the TXOP). However, because AP 2 shortens or terminates the TXOP early, the primary channel is idle before the end of the initial TXOP, and AP 1 and non-AP STA 1 will not participate in primary channel contention during this period, wasting primary channel resources. The following section combines... Figure 6 Please provide an explanation.

[0183] Figure 6 (a) is a schematic diagram illustrating the shortening of TXOP due to DUO. As shown, AP 2 and non-AP STA 1 communicate on the main channel. After AP 2 learns of the unavailability of non-AP STA 2 from the ICR, it terminates its transmission with non-AP STA 2 before the start of the unavailability and sends a CF-End to prematurely end the TXOP. For AP 1 and non-AP STA 1, they will trigger NPCA based on ICF or ICR. For example, after detecting the downlink PPDU of AP 2 (e.g., at time #1), they switch to the NPCA main channel, and switch back to the main channel at the end of the initial TXOP of AP 2 (e.g., at time #3). However, AP 2 has already ended the TXOP at time #2, and there is no signaling transmission on the main channel between time 2 and time 3, wasting the resources of the main channel. In the figures of this application, P20 represents the main channel, and NPCA P20 represents the NPCA main channel. The unavailability period is a period of time determined based on the start time of unavailability and the duration of unavailability.

[0184] Figure 6 (b) is a schematic diagram showing that TXOP terminates directly after ICR due to DUO. As shown, after AP 2 learns of the unavailability of non-AP STA 2 from ICR, it terminates TXOP directly considering that there is not enough time for data transmission. For AP 1 and non-AP STA 1, they will trigger NPCA based on ICF or ICR. For example, they will switch to the NPCA main channel after ICR (e.g., at time #1) and switch back to the main channel at the end of AP 2's initial TXOP (e.g., at time #3). However, AP 2 has already ended TXOP at time #2'. Between time #2' and time #3, there is no signaling transmission on the main channel, wasting the main channel resources.

[0185] On the other hand, during the above process, after AP 2's TXOP ends early, other stations may compete for the channel and set a new NAV. However, AP 1 and non-AP STA 1 do not have the latest NAV information after switching back to the main channel at time #3. Therefore, they are in a state of medium sync loss, which may cause AP 1 and non-AP STA 1 to misjudge the channel status and interfere with the transmission of other stations.

[0186] It should be understood that in the current NPCA rules, NPCA can be triggered by OBSS control frame interaction or OBSS HEPPDU, EHT PPDU or UHR PPDU, and switch back to the main channel based on the end time of OBSS TXOP.

[0187] For example, when the NPCA mechanism and the Co-BF mechanism coexist, the non-AP STA associated with the Co-BF AP may be triggered by the Co-BF ICF or ICR to initiate NPCA, resulting in problems such as being unable to respond to the ICR to the AP associated with it and being unable to participate in the measurement and transmission process.

[0188] Specifically, with Figure 3 Taking the Co-BF transmission phase frame interaction process as an example, frame interaction during the Co-BF transmission phase occurs entirely on the main channel. However, considering the NPCA mechanism, ICF1 and ICR1 are OBSS control frames for non-AP STA2, which may trigger NPCA for non-AP STA2. If non-AP STA2 is triggered by ICF1 or ICR1, for example, if non-AP STA2 switches to the NPCA main channel at time #1, then non-AP STA2 will switch to the NPCA main channel until the entire TXOP ends. This will cause non-AP STA2 to be unable to reply to ICR 2 on the main channel and will also be unable to receive DL PPDU transmissions from AP 2, resulting in wasted transmission resources.

[0189] Similarly, during the Co-BF measurement phase and the Co-SR transmission phase, the ICF or ICR interaction between AP1 and non-AP STA1 will also trigger non-AP STA2 to perform NPCA, causing non-AP STA2 to be unable to participate in Co-BF measurement or Co-SR transmission, thus wasting transmission resources.

[0190] In view of this, this application proposes a communication method and communication device that can improve resource utilization when NPCA mechanism and DUO mechanism coexist, or when NPCA mechanism and multi-AP cooperation mechanism coexist.

[0191] It should be understood that the embodiments shown below use a first station, a second station, etc., as examples to illustrate the method, but this application does not limit the execution subject. Any program that can run the code of the method provided in the embodiments of this application can communicate according to the method provided in the embodiments of this application. The execution subject of the method provided in the embodiments of this application can be a first station, a second station, etc., or a functional module within the first station, second station, etc., capable of calling and executing the program; there are no limitations.

[0192] Figure 7 This is a schematic flowchart of a communication method 700 provided in this application. This method can be used to solve the problem of the coexistence of the NPCA mechanism and the DUO mechanism, such as... Figure 7 As shown, the method 700 includes the following steps.

[0193] S710, the second station sends a first frame to the first station on the first main channel, and correspondingly, the first station receives the first frame on the first main channel, wherein the first frame is used to query the unavailability information of the station associated with the second station, or the first frame is used to carry the unavailability information of the second station.

[0194] The first frame is an interaction frame between the second station and its associated station. The BSS to which the second station belongs and the BSS to which the first station belongs are each other's OBSS, or in other words, the second station is the OBSS station of the first station. Therefore, the first station can receive the first frame and parse out some or all of the information in the first frame.

[0195] As an example, the second station could be a second AP. The second AP sends a first frame to inquire about the unavailability of a second non-AP STA, which is associated with the second AP.

[0196] Specifically, when the second non-AP STA enables DUO mode, the second AP queries the second non-AP STA for unavailability information through the first frame. After receiving the first frame, the second non-AP STA can send feedback on the unavailability information of the second non-AP STA to the second AP.

[0197] As another example, the second station could be a second non-AP STA, which sends the first frame to carry information about its unavailability.

[0198] Specifically, when the second non-AP STA enables DUO mode, the second AP queries the second non-AP STA for its unavailability information. The second non-AP STA can report its unavailability information to the second AP through the first frame.

[0199] The first site can be called the NPCA site, which is the first AP or the first non-AP STA. The first non-AP STA is associated with the first AP. The BSS to which the first non-AP STA and the first AP belong can be denoted as the first BSS, and the BSS to which the second non-AP STA and the second AP belong can be denoted as the second BSS. The first BSS and the second BSS are each other's OBSS.

[0200] For example, unavailability information can refer to time information about when the second station cannot use WLAN technology to communicate. For instance, it may include one or more of the following: the start time of unavailability, the end time of unavailability, and the duration of unavailability. Specifically, the unavailability information in this application can refer to the unavailability information in the DUO mechanism, i.e., DUO information.

[0201] For example, the first main channel is a main 20MHz channel.

[0202] S720, if the first station detects the first PPDU in the TXOP of the first frame and the first PPDU meets the conditions for triggering NPCA, the first station switches from the first main channel to the second main channel.

[0203] The TXOP containing the first frame can be set by the second station using the first frame. For example, the Duration field in the first frame can indicate the end time of the TXOP. Figure 6 As shown in (b), the first frame is an ICF. Alternatively, the TXOP containing the first frame can be updated by the second station via a CF-End frame, for example, as... Figure 6 As shown in (a), the first frame is the ICF. AP 2 indicates the end time of the TXOP through the Duration field in the ICF and then sends a CF-End frame to indicate that the TXOP ends early. That is, the CF-End frame updates the TXOP. The TXOP in which the first frame is located ends when the CF-End frame is sent.

[0204] If the first station detects a first PPDU that can trigger NPCA before the end of the TXOP where the first frame is located, the first station will trigger NPCA, that is, switch from the first primary channel to the second primary channel. The second primary channel is the NPCA primary channel, for example, the NPCA primary 20MHz channel, which is different from the primary 20MHz channel.

[0205] The first PPDU can be a PPDU sent by the second station or a PPDU sent by a station associated with the second station. In other words, the sender of the first PPDU and the sender of the first frame can be the same or different. It should be understood that for the first station, the first PPDU belongs to the OBSS PPDU, or the Inter-BSS PPDU.

[0206] For example, the conditions for triggering NPCA may include: the duration for which the first PPDU occupies the first main channel is greater than a second threshold, the channel occupied by the first PPDU does not overlap with the second main channel, etc. Wherein, the channel occupied by the first PPDU does not overlap with the second main channel, which can also be described as the first PPDU not occupying the second main channel, or in other words, the channel occupied by the first PPDU is located in a channel other than the second main channel.

[0207] Optionally, in this application, "the condition that triggers NPCA" may refer to the condition that triggers NPCA at the first station. For example, the NPCA conditions may be different for different stations, in which case the "condition that triggers NPCA" mentioned in this application is a condition specific to the first station.

[0208] The first PPDU can be a data PPDU, and the first PPDU and the first frame belong to the same TXOP.

[0209] As one implementation approach, the second threshold can be the NPCA minimum duration threshold, or an NPCA minimum duration threshold based on the PPDU length. This threshold can be defined by the protocol or set by the AP corresponding to the NPCA site. It should be understood that when the NPCA site is the first AP, the AP corresponding to the NPCA site is the first AP; when the NPCA site is the first non-AP STA, the AP corresponding to the NPCA site refers to the site associated with the NAPC site, i.e., the first AP, and this threshold can be set by the first AP.

[0210] For example, the moment when the first station begins switching to the second primary channel is after the start time of the first PPDU. For instance, it could be after the L-SIG LENGTH field of the first PPDU, since the L-SIG LENGTH field indicates the length of the first PPDU, thus allowing the determination of the relationship between the duration of the first PPDU and the second threshold. Alternatively, it could be after the high efficient signal A (HE-SIG-A) or U-SIG field of the first PPDU.

[0211] S730, the first station switches from the second primary channel to the first primary channel based on the end time of the first PPDU.

[0212] The switching from the second primary channel to the first primary channel based on the end time of the first PPDU can be replaced by: completing the switching from the second primary channel to the first primary channel no later than the end time of the first PPDU. Specifically, the switching can be completed before the end time of the first PPDU, or the end time of the first PPDU and the completion time of the switching from the second primary channel to the first primary channel can be aligned. Here, "aligned" means approximately aligned; as long as the difference between the end time of the first PPDU and the completion time of the switching of the first primary channel is less than a certain duration, it can be considered aligned. Alternatively, the switching from the second primary channel to the first primary channel based on the end time of the first PPDU can be replaced by: starting the switching from the second primary channel to the first primary channel no later than the end time of the first PPDU. That is, the start time of the switching is before the end time of the first PPDU, or aligned with the end time of the first PPDU.

[0213] For example, the end time of the first PPDU can be obtained from the LENGTH field of the L-SIG field of the preamble of the first PPDU (i.e., the L-SIG LENGTH field of the first PPDU).

[0214] For example, S720 and S730 can be regarded as PPDU length based NPCA mechanism, that is, when a PPDU that meets the conditions for triggering NPCA is detected, the main channel is switched to the NPCA main channel, and the main channel is switched back based on the end time of the PPDU.

[0215] Based on the above scheme, when the first station detects the interaction of the OBSS station with unavailability information, the first station can enable NPCA based on the PPDU length. That is, when a PPDU that meets the conditions for triggering NPCA is detected, the first station switches from the main channel to the NPCA main channel, and switches back to the main channel based on the end time of the PPDU. In this way, the first station can switch back to the main channel in time to compete for the channel and avoid wasting the transmission resources of the main channel when the OBSS TXOP ends prematurely.

[0216] In addition, since the first station can switch back to the main channel in a timely manner, it can learn about the latest status of the main channel and avoid losing media synchronization.

[0217] For example, with Figure 8For example, AP2 sends an ICF to non-AP STA2 to inquire about its unavailability. Non-AP STA2 replies with an ICR, carrying its own unavailability information. Further, AP2 sends a downlink PPDU to non-AP STA2, and non-AP STA2 replies with a BA. For AP1 and non-AP STA1, they will switch to the NPCA primary channel after detecting AP2's downlink PPDU (e.g., at time #1), and switch back to the primary channel at the end of AP2's initial TXOP (e.g., at time #4). Furthermore, based on the unavailability information of non-AP STA2, AP2 can know that non-AP STA2 is unavailable during its TXOP. In order to avoid transmission failure between AP2 and non-AP STA2, AP2 sends CF-End to prematurely end the TXOP before the start of non-AP STA2's unavailability. At this time, AP1 and non-AP STA1 have already switched back to the main channel and can know the information that the TXOP has ended prematurely. AP1 and non-AP STA1 can compete for the main channel after the TXOP ends, thus avoiding wasting the main channel's resources.

[0218] Optionally, Figure 6 The NPCA mechanisms shown in (a) and (b) can be considered as TXOP length-based NPCA, meaning that when the conditions for triggering NPCA are met, the system switches to the NPCA main channel, and switches back to the main channel based on the end time of the TXOP. In contrast, the PPDU length-based NPCA provided in this application can switch back to the main channel based on the end time of the PPDU. The PPDU length-based NPCA can also be called PPDU duration-based NPCA, PPDU-based NPCA, PPDU-level NPCA, etc. Similarly, the TXOP length-based NPCA can also be called TXOP duration-based NPCA, TXOP-based NPCA, TXOP-level NPCA, etc.

[0219] Considering that multiple PPDUs may be transmitted within a TXOP, the main difference between NPCA based on TXOP length and NPCA based on PPDU length lies in the timing of the switchback from the NPCA main channel to the main channel. Suppose the first PPDU within an OBSS TXOP triggers the station's NPCA, causing the station to switch to the NPCA main channel. In NPCA mode based on TXOP length, the station will switch back to the main channel at the end of the OBSS TXOP. However, in NPCA mode based on PPDU length, the station will switch back to the main channel at the end of the first OBSS PPDU. Subsequent OBSS PPDUs may trigger the station's NPCA again; for example, the station might switch back to the NPCA main channel upon detecting the second OBSS PPDU, and then switch back to the main channel at the end of the second OBSS PPDU.

[0220] It should be understood that when the first station is triggered by an NPCA based on the TXOP length, it can perform NPCA based on the OBSS TXOP length. That is, the first station will switch back to the main channel from the NPCA main channel according to the end time of the OBSS TXOP. If the NPCA is triggered by an OBSS control frame interaction, the TXOP length information can be obtained from the Duration field of the Medium Access Control (MAC) frame header. If the NPCA is triggered by an OBSS HE PPDU, the TXOP length information can be obtained from the TXOP field of the HE-SIG-A field of the PPDU preamble. If the NPCA is triggered by an OBSS EHT PPDU or UHR PPDU, the TXOP length information can be obtained from the TXOP field of the U-SIG field of the PPDU preamble.

[0221] For example, the minimum duration threshold of NPCA based on TXOP length (denoted as the third threshold) and the minimum duration threshold of NPCA based on PPDU length (i.e., the second threshold) can be the same or different. The second threshold and / or the third threshold can be predefined by the protocol or set by the NPCA site or the site associated with the NPCA (such as the first AP).

[0222] The following is a detailed explanation of the first frame.

[0223] As in implementation method 1, the first frame is a first initial control frame (ICF), and the first ICF satisfies at least one of the following conditions: (1) The first ICF is a BSRP frame. The BSRP frame includes response type indication information, which is used to indicate that the response type of the first frame is unavailability feedback. Condition (1) can also be understood as: the response type of the ICF is DUO feedback.

[0224] (2) The first ICF is a BSRP frame, which includes ICF type indication information. The ICF type indication information is used to indicate that the first ICF is used to query unavailable information. Here, condition (2) can also be understood as: the ICF type is a DUO ICF or an ICF that supports non-AP STA DUO mode.

[0225] (3) The first ICF is a BSRP frame, which includes the GI And HE / UHR-LTF Type field, and the value of the GI And HE / UHR-LTF Type field is 3. Here, condition (3) can also be understood as: the ICF is a BSRP GI3 frame, and the BSRP GI3 frame is a BSRP frame that solicits a Multi-STA BA frame carried on a non-HT PPDU as a response.

[0226] (4) The first ICF is a BSRP frame, which includes a UL length field. The value of the UL length field is greater than the first threshold. Here, condition (4) can be understood as the response frame of the first ICF need to be set long enough so that the peer station can carry unusable information in the response frame.

[0227] (5) The first ICF is a BSRP frame. The BSRP frame includes the CS required field, and the value of the CS required field is 1.

[0228] It should be understood that in this application, a BSRP frame can be replaced with a BSRP trigger frame, and a BSRP GI3 frame can be replaced with a BSRPGI3 trigger frame. In this application, querying for unavailable information can be replaced with soliciting unavailable information or requesting unavailable information.

[0229] When the first frame is an ICF and meets at least one of the above conditions, it means that the first frame may be an ICF used to query unavailable information or an ICF used to carry unavailable information. In this case, the first ICF can be called a DUO ICF. The first station can determine that the TXOP where the first frame is located may be shortened. Therefore, the first station can enable NPCA based on the PPDU length so that it can switch back to the main channel in time, avoid wasting the resources of the main channel, and improve resource utilization.

[0230] In addition, the first station can use the information carried in the ICF as a judgment condition without the need for additional indication information, which can make more efficient use of non-main channel resources while avoiding wasting main channel access opportunities.

[0231] In addition, ICF can contain more information and is easier to decode, which can improve the processing efficiency of the first station and save power.

[0232] In the above conditions, the response type and ICF type can correspond to each other. The ICF type indicates that the first ICF is an ICF used to query unavailability information, and correspondingly, the response type is unavailability information feedback. When the second AP indicates that the response type in the first ICF is unavailability information feedback, the second non-AP STA detects this response type and replies with unavailability information. Similarly, when the second AP indicates that the ICF type in the first ICF is an ICF used to query unavailability information, the second non-AP STA detects this ICF type and replies with unavailability information.

[0233] For example, the indication of the ICF response type can be carried in the Common Info field or the Special UserInfo field.

[0234] For example, any of the above-mentioned BSRPs may include a User Info field, in which the association identifier (AID) field 12 can be set to the AID of the STA that is being queried for unavailability information. For example, when the second AP queries the second non-AP STA for unavailability information, the AID field 12 in the BSRP can be the AID of the second non-AP STA.

[0235] It should be understood that the first ICF can be sent by either the second AP or the second non-AP STA. For example, when the second non-AP STA has DUO mode enabled, the second AP, acting as the TXOP holder, sends an ICF to the second non-AP STA as the start of frame interaction. This ICF is used to inquire about the unavailability information of the second non-AP STA; in this case, the ICF is a BSRP frame. Alternatively, if the second non-AP STA is the TXOP holder, it can also proactively send an ICF to the second AP, carrying its own unavailability information within the ICF; in this case, the ICF can also be a BSRP frame.

[0236] As in implementation method 2, the first frame is used to carry the unavailability information of the second station. The first frame is a first ICR frame, and the first ICR frame satisfies at least one of the following conditions: (1) The first frame is a Multi-STA BA frame.

[0237] (2) The first frame is a Multi-STA BA frame, and the Multi-STA BA frame includes information about the unavailability of the second station.

[0238] (3) The first frame is a Multi-STA BA frame, and the PPDU carrying the Multi-STA BA frame is a non-HT PPDU.

[0239] (4) The first frame is a Multi-STA BA frame, and the value of the L-SIG LENGTH field in the PPDU carrying the Multi-STA BA frame is greater than the first threshold.

[0240] In this application, an ICR frame can be abbreviated as ICR. Therefore, ICR in this document can refer to an ICR frame, and the first ICR can refer to the first ICR frame.

[0241] For example, the first ICR can be sent by the second non-AP STA. For instance, after receiving the ICF sent by the second AP, the second non-AP STA needs to reply with an ICR, carrying unavailability information in the ICR. In this case, the ICR can be a Multi-STA BA frame. For example, the unavailability information is carried in the perassociation identifier traffic identifier information (Per AID TID Info) field of the Multi-STA BA frame.

[0242] When the first frame is an ICR and meets at least one of the above conditions, it indicates that the first frame may be an ICR used to carry unusable information. In this case, the first ICR can be called a DUO ICR. The first station can determine that the TXOP where the first frame is located may be shortened. Therefore, the first station can enable NPCA based on the PPDU length so that it can switch back to the main channel in time, avoid wasting the resources of the main channel, and improve resource utilization.

[0243] In addition, the first station can use the information carried in the ICR as a judgment condition without the need for additional indication information, which can make more efficient use of non-main channel resources while avoiding wasting main channel access opportunities.

[0244] As an implementation method 3: the first frame is the first ICF, the first ICF includes first indication information, the first indication information is used to indicate whether there is a possibility of updating the transmission opportunity TXOP where the first ICF is located.

[0245] The possibility of updating the TXOP can include one or more of the following: whether the duration of the TXOP will be shortened, whether the duration of the TXOP will be extended, and whether the transmission bandwidth within the TXOP will be updated.

[0246] For example, the first indication information can be 1 bit. For instance, when the indication bit is set to 1, it indicates that the TXOP containing the ICF is guaranteed not to be shortened, or in other words, there is no possibility of shortening. When the indication bit is set to 0, it indicates that it is uncertain whether the TXOP containing the ICF will be shortened, or in other words, there is a possibility of shortening. Alternatively, the indication bit can be set to 1 to indicate that the TXOP may be shortened, and set to 0 to indicate other situations.

[0247] For example, the first indication information can also use more bits to correspond to more granular situations. For instance, using 2 bits to indicate that setting 0 means it is uncertain whether the duration and bandwidth of the TXOP may be updated; setting 1 means it is uncertain whether the duration of the TXOP may be updated, but the bandwidth is guaranteed not to be updated; setting 2 means it is guaranteed that the duration of the TXOP will not be updated, but it is uncertain whether the bandwidth may be updated; and setting 3 means it is guaranteed that neither the duration nor the bandwidth of the TXOP will be updated.

[0248] It should be understood that the specific instructions for the first instruction information described above are merely illustrative examples, and this application is not limited to the above methods.

[0249] Specifically, when the first indication information indicates that the transmission opportunity TXOP of the first ICF is likely to be updated, the first station can enable NPCA based on the PPDU length, i.e., execute S720 and S730 until the end time of the TXOP indicated in the ICF, or until the first station receives the CF-End frame. Alternatively, when the first indication information indicates that the transmission opportunity TXOP of the first ICF is likely to be updated, the first station can choose not to perform NPCA, i.e., remain on the main channel without channel switching, until the end time of the TXOP indicated in the ICF, or until the first station receives the CF-End frame. When the first indication information indicates that the transmission opportunity TXOP of the first ICF is not likely to be updated, the first station can enable NPCA based on the TXOP length until the end time of the TXOP.

[0250] It should be noted that when the first indication information indicates that the transmission where the first ICF resides may have a TXOP that needs updating, the OBSS may update the NAV information during frame exchanges. For example, the NAV end time indicated in the ICR may be earlier than the NAV end time indicated in the ICF, or the NAV end time indicated in the PPDU after the ICR may be earlier than the NAV end time indicated in the ICR. If the station still needs to perform NPCA based on the TXOP length in this case, it can perform NPCA according to the updated TXOP length. For example, if a station is triggered to perform NPCA by the OBSS ICF, but does not start switching to the NPCA main channel until some time after receiving the ICR, and if the received ICR indicates an earlier NAV end time, the duration of residing on the NPCA main channel is set according to the updated NAV.

[0251] For example, the first ICF can be a BSRP frame, and the first indication information is carried in the public information field or special user information field of the BSRP frame; or, the first ICF can be a MU-RTS frame, and the first indication information is carried in the public information field or special user information field of the MU-RTS frame.

[0252] Figure 9 This is a schematic diagram of the public information fields and special user information fields of the ICF provided in the embodiments of this application, as shown below. Figure 9 As shown in (a), B22, B26, B53, and B61-63 in the public information field are currently reserved bits, and the first indication information can be located in any of these bits. Figure 9 As shown in (b), B37-39 in the special user information field are currently reserved bits, and the first indication information can be located in any of the above bits.

[0253] Based on the above scheme, by adding first indication information to the first ICF, other stations can be clearly informed whether the TXOP of the second station may be updated. Thus, the first station can take corresponding NPCA actions based on the first indication information, thereby improving channel utilization efficiency.

[0254] Optionally, the first indication information can also be used to instruct the second station to allow the first station to reset the NAV timer set according to the first frame. For example, this indication can also be used in BSRP to indicate whether NAV reset is allowed; if there is a possibility that the TXOP will be shortened, NAV reset is allowed; if there is no possibility that the TXOP will be shortened, NAV reset is not allowed. The reason for this setting is that NAV reset can only occur when the TXOP is terminated prematurely.

[0255] Optionally, the method 700 further includes: the first station determining, based on the first instruction information, whether to perform opportunistic energy saving within the TXOP where the first ICF is located.

[0256] Specifically, if the first indication information indicates that there is no possibility of the TXOP being shortened, the first station can perform NPCA based on the TXOP length and can opportunistic energy saving within the TXOP until the TXOP end time indicated by the ICF. This avoids frequent channel switching by the first station and saves overhead. If the first indication information indicates that the TXOP is likely to be shortened, the first station can perform NPCA based on the PPDU length until the TXOP end time indicated in the ICF, or until the CF-End frame is received. This avoids the first station missing necessary information and losing media synchronization, and also saves power without wasting the main channel access opportunity. Alternatively, if the first indication information indicates that the TXOP is likely to be shortened, the first station can skip NPCA, thus avoiding opportunistic energy saving.

[0257] As an implementation method 4: the first frame is the first ICF, the first ICF includes second indication information, the second indication information is used to indicate the type of NPCA performed within the TXOP of the first ICF by the site that is an OBSS with the BSS to which the second site belongs.

[0258] In this application, the type of NPCA can also be referred to as NPCA pattern, NPCA form, etc., without restriction.

[0259] Specifically, the second indication information can be used to indicate the NPCA type of the OBSS site. This type can include NPCA based on PPDU length, NPCA based on TXOP length, and no NPCA. Three specific indication methods for the second indication information are given below, which can be implemented using 1 bit or 2 bits.

[0260] Method 1: Use 1 bit to indicate.

[0261] When the indicator bit is set to 1, if a station is triggered to perform an NPCA by this ICF, an NPCA based on the TXOP length should be performed; when the indicator bit is set to 0, if a station is triggered to perform an NPCA by this ICF, an NPCA based on the PPDU length should be performed.

[0262] Method 2: Use 1 bit to indicate.

[0263] When this indicator bit is set to 0, a station should not be triggered NPCA by this ICF; when this indicator bit is set to 1, if a station is triggered NPCA by this ICF, an NPCA based on the TXOP length should be performed.

[0264] Method 3: Use 2 bits for indication. When the indication bit is set to 0, the station should not be triggered NPCA by this ICF; when the indication bit is set to 1, if a station is triggered NPCA by this ICF, an NPCA based on the PPDU length should be performed; when the indication bit is set to 2, if a station is triggered NPCA by this ICF, an NPCA based on the TXOP length should be performed; when the indication bit is set to 3, the meaning is reserved (it can be used for other purposes later).

[0265] It should be understood that the specific instructions for the second instruction information described above are merely illustrative examples, and this application is not limited to the above methods.

[0266] For example, the first ICF is a BSRP frame, and the second indication information is carried in the common information field or special user information field of the BSRP frame; or, the first ICF is a MU-RTS frame, and the second indication information is carried in the common information field or special user information field of the MU-RTS frame.

[0267] The formats of the ICF's public information fields and special user information fields are as follows: Figure 9 As shown, similar to the first instruction information, the second instruction information can also be located in any reserved bit in the public information field or the special user information field.

[0268] Based on the above scheme, when other stations (such as the first station) detect this ICF, they can determine which type of NPCA to perform or whether to perform NPCA based on the above indication. This allows the first station to clearly know from the indication bit which type of NPCA should be performed, thus avoiding wasting the main channel access opportunity while maximizing the utilization of the NPCA main channel resources.

[0269] As an implementation method 5: the first PPDU includes first indication information and / or second indication information. The first indication information is used to indicate whether there is a possibility of updating the transmission opportunity TXOP where the first PPDU is located. The second indication information is used to indicate the type of NPCA performed by the station that is an OBSS with the BSS to which the second station belongs within the TXOP where the first PPDU is located. The TXOP where the first PPDU is located is the same TXOP as the TXOP where the first frame is located.

[0270] Specifically, the first indication information and / or the second indication information can be directly located in the first PPDU, for example, carried in the preamble of the first PPDU, such as the U-SIG field or the UHR signaling (UHR-SIG) field. In this way, when the first station is triggered by the first PPDU to perform NPCA, the first station can obtain an indication of whether TXOP will be updated, or can obtain the type of NPCA, so that the first station can take the corresponding type of NPCA, or not perform NPCA, thereby improving the channel utilization efficiency.

[0271] The specific indication methods and meanings of the first and second indication information can be found in implementation methods 3 and 4.

[0272] As an implementation method 6: the first station is the first non-AP STA or the first AP. Before S710, the method 700 further includes: the first AP sends second indication information to the first non-AP STA on the first main channel, and correspondingly, the first non-AP STA receives the second indication information on the first main channel.

[0273] The second indication information for non-AP STA is used to indicate the type of NPCA of the non-AP STA associated with the first AP, and the non-AP STA associated with the first AP includes the first non-AP STA.

[0274] Specifically, when the first AP determines that the DUO mode is enabled at the OBSS site (such as the second site), it can send second indication information on the first main channel. The second indication information is used to indicate the type of NPCA of the non-AP STA associated with the first AP, or in other words, to indicate the type of NPCA of the sites within the first BSS, where the first BSS is the BSS to which the first non-AP STA and the first AP belong. For example, the second indication information can indicate at least one of the following NPCA types: (1) Disable NPCA of this BSS site, or in other words, prohibit sites in the first BSS from performing NPCA, or in other words, instruct sites in the first BSS not to perform NPCA.

[0275] (2) Restrict this BSS site to only perform NPCA based on PPDU length, or in other words, instruct the type of NPCA of the site in the first BSS to be NPCA based on PPDU length.

[0276] (3) Instruct that non-AP STAs associated with the first AP should not be triggered NPCA by the OBSS, wherein the determination of whether it is the OBSS can be made by informing the OBSS (such as the BSS to which the second site belongs) of the BSSID or BSS color.

[0277] (4) Indicates that a non-AP STA associated with the first AP can only be triggered by an OBSS in a list that does not include the OBSS.

[0278] (5) Indicates that the non-AP STA associated with it can only trigger NPCA based on PPDU length when the OBSS is detected.

[0279] For example, the second indication information may be carried in a beacon frame or probe response frame sent by the first AP.

[0280] Optionally, if the first AP determines that the second site has not enabled DUO mode, it may send a second indication message on the first main channel. The second indication message may be used to indicate that the type of NPCA of the non-AP STA associated with the first AP is an NPCA based on the TXOP length. Alternatively, the first AP may not send the second indication message.

[0281] The first AP can determine whether the second site has enabled DUO mode in any of the following ways: Method a: ICF or ICR sent via the second station. The ICF or ICR can be sent before the first frame. For example, the second AP can send the second ICF within the TXOP before the first frame. It can be used to inquire whether the second non-AP STA has unavailable information. The second non-AP STA replies with the second ICR, carrying its own unavailable information. Based on the second ICF or the second ICR, the first AP can determine that the second non-AP STA has enabled DUO mode. Therefore, the first AP can send the second indication information to the first non-AP STA before S710.

[0282] Method b: By detecting at least one of the beacon frames, probe response frames, or other management frames of the second BSS. Specifically, if the second AP or the second non-AP STA within the second BSS has enabled DUO mode, the second AP can indicate this through at least one of the beacon frames, probe response frames, or other management frames. Therefore, the first AP can determine whether the second site has enabled DUO mode by detecting the beacon frames, probe response frames, or other management frames of the second BSS.

[0283] Method c: The non-AP STA associated with the first AP can also detect whether the second site has enabled DUO mode. It can report to the first AP, so that the first AP can determine whether the second site has enabled DUO mode.

[0284] Optionally, in this implementation, when the first AP indicates the type of NPCA to the first non-AP STA, the first non-AP STA can continue to perform NPCA according to the type of NPCA indicated by the first AP until the first AP sends new second indication information.

[0285] It should be understood that the various implementation methods described above can be used in combination to determine whether to enable NPCA based on PPDU length at the first site. An example is provided below for illustration.

[0286] As an example, the various conditions in Implementation Method 1 and Implementation Method 2 can be combined. For instance, when the second AP sends a first ICF to inquire about the unavailability of the second non-AP STA, the first ICF can explicitly indicate that the response type of the ICF is an unavailability feedback. When the second non-AP STA detects that the response type of the first ICF is an unavailability feedback, it replies with a Multi-STA BA frame as the first ICR, carrying its own unavailability information in the Multi-STA BA frame. Alternatively, the first ICF may also indicate the type of the ICF, such as indicating that the type of the ICF is an ICF used to inquire about unavailability. After the second non-AP STA detects this ICF type, it replies with unavailability information via the first ICR. In both examples, the first station can receive both the first ICF and the first ICR, thus enabling NPCA based on PPDU length can be determined jointly based on the first ICF and the first ICR.

[0287] As another example, implementation methods 1 and 3 can be combined. For instance, if the first AP sends an ICF (Information Channel Request), which is a BSRP (Basic Standard Programming Responsibility Request) with a response type of "Unavailable," indicating that the ICF is used to query for unavailable information, then the second AP can include a first indication in the ICF, indicating that there is a possibility of TXOP (Turns To Open) shortening. In this case, the first station can determine the NPCA (Non-Performance Agreement) based on the PPDU (Presumably PPDU) length based on the first ICF. Alternatively, if the second AP only uses the ICF to protect the channel from interference and is certain that the entire TXOP will be used for transmission, then the ICF is not used to query for unavailable information, and the ICF includes a first indication, indicating that there is no possibility of TXOP shortening. In this case, the first station can determine the NPCA (Non-Performance Agreement) based on the TXOP length based on the first ICF.

[0288] As another example, implementation methods 1 and 4 can be combined. For instance, when the second AP sends an ICF, the type of the ICF and the characteristics of the TXOP in which the ICF resides need to be considered, and the bit values ​​of the aforementioned second indication information need to be set accordingly. For example, if the second indication information adopts the aforementioned indication method 1, and the ICF is used to query the unavailability information of the second non-AP STA, then the second indication information is set to 0, indicating that the NPCA site should perform NPCA based on the PPDU length.

[0289] Similarly, other different implementation methods can be combined with each other, which will not be elaborated here.

[0290] Alternatively, the above implementation methods can also be decoupled from method 700 and implemented independently, as illustrated below.

[0291] For example, implementation method 3 can be implemented independently. Specifically, the second station can generate and send a first ICF. The first ICF includes first indication information, which indicates whether there is a possibility of updating the TXOP containing the first ICF. For the station that receives the first ICF (such as the first station), it can know whether there is a possibility of updating the TXOP containing the first ICF. Furthermore, the first station can execute the NPCA based on the PPDU length in method 700, or it can execute other operations related to or unrelated to the NPCA.

[0292] For example, implementation method 4 can be implemented independently. Specifically, the second station can generate and send a first ICF. The first ICF includes second indication information, which indicates the type of NPCA for stations that are OBSSs with the BSS to which the second station belongs, within the TXOP where the first ICF is located. For a station that receives the first ICF (such as the first station), it can know the type of NPCA that should be performed within the TXOP where the first ICF is located. Furthermore, the first station can execute the NPCA based on the PPDU length in method 700, or it can execute other operations related to or unrelated to the NPCA.

[0293] For example, implementation method 5 can be implemented independently. Specifically, the second station can generate and send a first PPDU. The first PPDU includes first indication information and / or second indication information. The first indication information indicates whether there is a possibility of updating the TXOP where the first PPDU is located. The second indication information indicates the type of NPCA to be performed within the TXOP where the first PPDU is located by a station whose BSS is an OBSS with the second station. For the station receiving the first PPDU (such as the first station), it can know whether there is a possibility of updating the TXOP where the first PPDU is located based on the first indication information, and know the type of NPCA to be performed within the TXOP where the first PPDU is located based on the second indication information. Furthermore, the first station can perform the NPCA based on the PPDU length in method 700, or it can perform other operations related to or unrelated to NPCA. Optionally, the first frame mentioned above can be encapsulated in the first PPDU.

[0294] For example, implementation method 6 can be implemented independently. Specifically, the first AP can generate and send beacon frames, probe response frames, or other management frames. These frames include second indication information, which indicates the type of NPCA (National Security Procedure) performed by the non-AP STA associated with the first AP. The station receiving the second indication information (such as the first non-AP STA) can then determine the type of NPCA to be performed. Furthermore, the first non-AP STA can perform the NPCA based on the PPDU length in method 700, or perform other operations related to or unrelated to NPCA.

[0295] It should be understood that in this application, "not performing NPCA" can be regarded as a type of NPCA, that is, it can be regarded as an operation related to NPCA or an operation unrelated to NPCA, and there is no restriction.

[0296] Optionally, as an alternative to method 700, S710 can be omitted, meaning the first station defaults to NPCA based on the PPDU length. As long as the first PPDU meets the conditions for triggering NPCA, the first station can switch from the main channel to the NPCA main channel when detecting the PPDU, and switch back to the main channel based on the end time of the PPDU.

[0297] Alternatively, as an alternative to method 700, when the first frame meets the conditions in implementation mode 2, the first station can also perform NPCA based on the first frame (i.e., the first ICR), such that the time spent camping on the NPCA main channel can be set according to the NAV information indicated by the Duration field of the first ICR.

[0298] Specifically, in some cases, the first station can only detect the OBSS ICR (i.e., the first ICR) and not the first ICF. For example, when the second AP communicates with the second non-AP STA, the second AP sends the first ICF, and the second non-AP STA replies with the first ICR. The first station can only detect the frame of the second non-AP STA (i.e., the second AP is a hidden node of the first BSS), and therefore detects the first ICR. In one approach, detecting only the OBSS ICR may also trigger NPCA at the first station. In this case, the length information of the OBSS TXOP can be obtained from the Duration field in the ICR. However, if the ICR is a Multi-STA BA frame, considering that the Multi-STA BA may be used to carry unavailability information of the second non-AP STA, and the second AP may directly terminate the TXOP based on this unavailability information, the first station cannot determine whether the second AP or the second non-AP STA will continue to transmit based solely on the first ICR. If the first station performs NPCA, it may waste the access opportunity of the main channel. Therefore, the following rule can be introduced: If the first station only detects the OBSS ICR but not the corresponding ICF, and the ICR satisfies at least one of the conditions in implementation method 2, then the NPCA of the first station should follow either rule 1 or rule 2 as follows: Rule 1. NPCA shall not be performed unless an OBSS PPDU following an OBSS ICR is detected.

[0299] Rule 2. If the BSRP frame corresponding to the ICF allows NAV reset, NPCA will not be performed unless an OBSS PPDU is detected after the OBSS ICR; if the BSRP frame corresponding to the ICF does not allow NAV reset, NPCA can be performed based on the OBSS ICR, and the time spent camping on the NPCA main channel can be set according to the NAV information indicated by the Duration field of the ICR.

[0300] Rule 1 directly prohibits the first station from performing NPCA solely based on OBSS ICRs that meet the above conditions, because unless a subsequent OBSS PPDU (such as the first PPDU) is detected, it cannot be determined whether the OBSS TXOP will continue. In this case, camping on the main channel is beneficial for obtaining access to the main channel. If the station detects a subsequent PPDU (such as the first PPDU) in the OBSS ICR, it can still perform NPCA. For example, it can perform NPCA based on the PPDU length, which is implementation 2 of method 700, or it can perform NPCA based on the TXOP length.

[0301] Rule 2 above considers whether NAV reset is allowed in BSRP frames. NAV reset refers to the fact that if a station detects an ICF from the OBSS but does not detect a subsequent PPDU, it can reset the NAV set by the ICF to 0 after a timeout (NAVTimeout), thus enabling it to participate in channel contention. If NAV reset is allowed, and the OBSS stops transmitting after the ICF, the station can compete for the primary channel after NAVTimeout. Therefore, not performing NPCA based on ICR helps to obtain access opportunities on the primary channel. If NAV reset is not allowed, even if the OBSS stops transmitting after the ICF, the station's NAV will not be reset, and it cannot compete for the primary channel until the NAV reaches 0. Therefore, switching to the NPCA primary channel helps to improve channel utilization efficiency.

[0302] Optionally, as an alternative to method 700, when the first frame satisfies the conditions in implementation mode 1 or implementation mode 2, and the first frame includes an unavailability start time, the first station can switch from the second main channel to the first main channel based on the unavailability start time. In this case, the first frame in S710 including the unavailability start time can be replaced by: the first station switching from the second main channel to the first main channel based on the unavailability start time.

[0303] In other words, if the first frame indicates the start time of unavailability, and this start time is earlier than the end time of the TXOP containing the first frame, then the first station can switch back to the main channel from the NPCA main channel before the start time of unavailability, thus utilizing the NPCA main channel more efficiently. Specifically, even if the second station shortens the TXOP due to DUO, the shortened portion still falls within the unavailability period of the OBSS station. Therefore, the main channel will still be occupied by the OBSS station before the start time of its unavailability, during which the first station can still perform NPCA. When switching back to the main channel at the start time of the OBSS station's unavailability, the first station can promptly learn the status of the main channel, and can also compete for the main channel earlier if the OBSS TXOP terminates early.

[0304] In this alternative, the first frame can be the first ICR, the first ICR frame is a Multi-STA BA frame, and the PPDU carrying the Multi-STA BA frame is a non-HT PPDU. In this way, the first station can decode the first frame and obtain the unavailable start time.

[0305] Alternatively, as an alternative to method 700, when the first frame meets the conditions in implementation mode 1 or implementation mode 2, the first station may not perform NPCA. In this case, S720 and S730 can be replaced by: stopping NPCA before receiving the end indication of the TXOP containing the first frame; or stopping NPCA before the countdown of the NAV timer set according to the first frame ends. This avoids the problem of wasting main channel resources, that is, it avoids the problem of the first station wasting the main channel access opportunity due to switching to the NPCA main channel when the TXOP of the second station ends early.

[0306] Figure 10 This is a schematic flowchart of a communication method 1000 provided in this application. This method can be used to solve problems when NPCA mechanisms coexist with Co-BF or Co-SR mechanisms, such as... Figure 10 As shown, the method 1000 includes the following steps.

[0307] S1010, the second station sends a second frame on the first main channel, and correspondingly, the first station receives the second frame on the first main channel. The second frame is used to transmit control information in the first multi-AP cooperation process, and the second station participates in the first multi-AP cooperation process.

[0308] In this application, the multi-AP collaboration process can also be called a multi-AP collaboration mechanism. Therefore, the first multi-AP collaboration process can be called the first multi-AP collaboration mechanism, for example, a Co-SR process or a Co-BF process. Specifically, it can be a Co-SR transmission process, a Co-BF transmission process, or a Co-BF measurement process.

[0309] In method 1000, the second station can be a station participating in the first multi-AP cooperation process, or in other words, the second station is related to the first multi-AP cooperation process. Therefore, the second frame can be a frame in the first multi-AP cooperation process. Specifically, the second frame is a frame used to transmit control information that is exchanged between the second station and its associated station in the first multi-AP cooperation process.

[0310] For example, if the second site is the second AP, and the first multi-AP collaboration process is a Co-BF process, then the second frame can be the ICF (Integrated Function Frame) within the Co-BF process. Specifically, when the second AP is a shared AP, the second frame can be... Figure 3 The Co-BF invitation frame and ICF 1 in the text, such as Figure 4 The measurement invitation frame, ICF, etc., are included. When the second AP is the shared AP, the second frame can be... Figure 3 Co-BF response frames, ICF2, etc. Figure 4 Measurement response frames, etc.

[0311] For example, if the second site is the second non-AP STA, and the first multi-AP collaboration process is a Co-BF process, the second frame can be the ICR in the Co-BF process. Specifically, when the AP associated with the second non-AP STA is a shared AP, the second frame can be... Figure 3 ICR1 in, such as Figure 4 In the ICR, when the AP associated with the second non-AP STA is a shared AP, the second frame can be... Figure 3 ICR 2 in the middle.

[0312] For example, if the second site is the second AP, and the first multi-AP collaboration process is a Co-SR process, the second frame can be the ICF in the Co-SR process. Specifically, when the second AP is a sharing AP, the second frame can be... Figure 5 The Co-SR invitation frame, ICF1, etc. When the second AP is the shared AP, the second frame can be... Figure 5 Co-SR response frames, ICF2, etc.

[0313] For example, if the second site is the second non-AP STA, and the first multi-AP collaboration process is a Co-SR process, the second frame can be the ICR in the Co-SR process. Specifically, when the AP associated with the second non-AP STA is a shared AP, the second frame can be... Figure 5 In ICR1; when the AP associated with the second non-AP STA is a shared AP, the second frame can be Figure 5 ICR2, etc.

[0314] For example, the Co-BF invitation frame, measurement invitation frame, and Co-SR invitation frame mentioned above can be BSRP frames, and the Co-BF response frame, measurement response frame, and Co-SR response frame mentioned above can be Multi-STA BA frames.

[0315] The first site can be called the NPCA site. Specifically, the first site can be the first AP or the first non-AP STA. The first non-AP STA is associated with the first AP.

[0316] Furthermore, the BSS to which the first non-AP STA and the first AP belong can be denoted as the first BSS, and the BSS to which the second non-AP STA and the second AP belong can be denoted as the second BSS. The first BSS and the second BSS are each other's OBSS.

[0317] In this system, the BSS belonging to the second station and the BSS belonging to the first station are each other's OBSS, or in other words, the second station is the OBSS station of the first station. Therefore, the first station can receive the second frame and parse some or all of the information in the second frame. Specifically, the first station can determine whether the second frame is a frame in the Co-SR procedure or the Co-BF procedure by detecting the type indication of the second frame, or in other words, determine whether the second frame is used in the Co-SR procedure or the Co-BF procedure.

[0318] It should be understood that determining whether a PPDU originates from the local BSS (i.e., intra-BSS PPDU) or the OBSS (i.e., inter-BSS PPDU) can be done using the basic service set identifier (BSSID) or BSScolor. The BSSID consists of 48 bits and can be carried in the MAC frame header. The BSScolor consists of 6 bits and is carried in the preamble of HE PPDU, EHT PPDU, and UHR PPDU; different BSSs typically have different BSScolors. Using the BSScolor, the first station can distinguish whether a received PPDU originates from its own BSS or the OBSS. In Co-SR or Co-BF procedures, the preamble of downlink data PPDUs can include the BSScolors of all APs participating in the Co-SR or Co-BF procedure.

[0319] S1020a, if the first station does not participate in the first multi-AP cooperation process and the first PPDU is detected to meet the conditions for triggering NPCA, the first station switches from the first primary channel to the second primary channel, which is the NPCA primary channel.

[0320] For a description of the first and second main channels, as well as the conditions for triggering NPCA, please refer to Method 700, which will not be repeated here.

[0321] The first PPDU refers to the downlink data PPDU in the first multi-AP collaborative process, such as a Co-BF data PPDU or a Co-SR data PPDU. The Co-BF data PPDU can also be called a Co-BF PPDU or a Co-BF DL PPDU, and the Co-SR data PPDU can also be called a Co-SR PPDU or a Co-SR DL PPDU. Furthermore, the first PPDU can be sent by the sharing AP or by the AP being shared.

[0322] In other words, the first station can be a station that does not participate in the first multi-AP cooperation process, or in other words, the first station is unrelated to the first multi-AP cooperation process. The first station only starts switching from the first primary channel to the second primary channel when it detects downlink data PPDU in the first multi-AP cooperation process.

[0323] For example, the first station may begin switching from the first primary channel to the second primary channel after detecting the general signaling field U-SIG of the first PPDU. Specifically, the timing of starting the switch from the first primary channel to the second primary channel is any of the following: (1) Start timing from the start time of the first PPDU, and then the signaling time (SIG_TIME) is elapsed. That is, start timing from the start time of the first PPDU, and start switching after SIG_TIME has elapsed.

[0324] (2) Start timing from the beginning of the first PPDU, with an interval of SIG_TIME and one slot duration (aSlotTime). That is, start timing from the beginning of the first PPDU, and start switching after SIG_TIME + one slot duration.

[0325] (3) The timing starts from the start time of the first PPDU, and is timed by SIG_TIME, one receiver physical layer start delay (aRxPHYStartDelay), and one time slot duration. That is, the timing starts from the start time of the first PPDU, and the handover begins after SIG_TIME + aRxPHYStartDelay + one time slot duration.

[0326] SIG_TIME is the duration from the start of the PPDU to the end of the HE-SIG-A or U-SIG field, typically 32 microseconds (µs). aSlotTime and aRxPHYStartDelay are values ​​defined in the IEEE 802.11 protocol.

[0327] For the three options mentioned above, if the switching start time starts from the end time of the Co-BF trigger frame or the Co-SR trigger frame, simply add the duration of a short interframe space (SIFS) (aSIFSTime) to the duration of each of the three options, where aSIFSTime is a value defined in the IEEE 802.11 protocol.

[0328] All three options begin switching to the NPCA main channel after detecting the U-SIG field of the preamble of the first PPDU. Adding an extra duration in options 2 and 3 ensures that the first station has sufficient time to determine whether to perform NPCA.

[0329] Based on the above scheme, since the U-SIG field and the fields preceding the U-SIG field contain the necessary information for determining whether to perform NPCA, for example, the L-SIG field preceding the U-SIG field includes the LENGTH field, and the U-SIG field includes the TXOP field and the BSS Color field, etc., switching can begin after the U-SIG field of the first PPDU is detected, thus obtaining the necessary information for determining whether to perform NPCA, which facilitates the first site to make a decision.

[0330] For example, the first PPDU includes N BSS colors. These N BSS colors include the BSS colors of the BSS belonging to the site participating in the first multi-AP collaboration process. If the first site does not participate in the first multi-AP collaboration process, the N BSS colors and the BSS colors of the BSS to which the first site belongs are all different; or, if the first site does not participate in the first multi-AP collaboration process, the N BSS colors include the BSS colors of the BSS to which the first site belongs. N is an integer greater than or equal to 2. In other words, the first site can determine whether it participates in the first multi-AP collaboration process based on the BSS colors included in the first PPDU.

[0331] Specifically, since the first PPDU is the downlink data PPDU in the first multi-AP collaboration process, the U-SIG field of the first PPDU will include the BSS colors of all APs participating in the first multi-AP collaboration process. For example, if there are N APs participating in the first multi-AP collaboration process, then the first PPDU includes N BSS colors. These N BSS colors include the second BSS color belonging to the second site. The first site can parse the U-SIG field and compare it with its own BSS color one by one. If they are all different, it means that the first site is not related to the first multi-AP collaboration process, and the first site can trigger NPCA. If one is the same, it means that the first site is related to the first multi-AP collaboration process, and the first site will not trigger NPCA.

[0332] For example, there are 2 APs participating in the first multi-AP collaboration process, i.e., N=2. Their BSS colors are denoted as BSS color1 and BSS color2. When the BSS color of the BSS to which the first site belongs is different from both BSS color1 and BSS color2, it means that the first site is not related to the first multi-AP collaboration process.

[0333] Alternatively, method 1000 can also be understood as follows: even if the second frame meets the conditions for triggering NPCA, and the first station is not related to the first multi-AP cooperation process in which the second frame is located, the first station will not immediately switch to the second primary channel after the second frame. Instead, it will start switching from the first primary channel to the second primary channel when it detects the downlink data PPDU of the first multi-AP cooperation process. Alternatively, it can be understood that the second frame does not meet the conditions for triggering NPCA, so the first station will perform NPCA when it detects that the first PPDU meets the conditions for triggering NPCA.

[0334] S1020b, when the first station participates in the first multi-AP cooperation process and detects the second frame or the first PPDU, the first station stays on the first main channel within the TXOP where the first multi-AP cooperation process is located and does not perform NPCA.

[0335] Specifically, the first site can participate in the first multi-AP collaboration process. For example, the first site is the first AP, and the first AP participates in the first multi-AP collaboration process; or, the first site is the first non-AP STA, and the first AP associated with the first non-AP STA participates in the first multi-AP collaboration process.

[0336] S1020b can also be understood as follows: when the first site participates in the first multi-AP collaboration process, the control frames (such as the second frame) and downlink data PPDUs (such as the first PPDU) in the first multi-AP collaboration process will not trigger the first site to perform NPCA, thus ensuring that the first multi-AP collaboration process in which the first site participates can proceed normally.

[0337] Based on the above scheme, when the first station does not participate in the first multi-AP cooperation process being carried out by the OBSS station, the first station can start switching to the NPCA main channel only when it detects the downlink data PPDU of the OBSS station. When the first station participates in the first multi-AP cooperation process, the first station does not perform NPCA within the TXOP where the first multi-AP cooperation process is located. In other words, the OBSS control frame or downlink data PPDU in the multi-AP cooperation process in which the first station participates will not trigger the first station to switch to the NPCA main channel. The first station will only switch to the NPCA main channel when it detects the downlink data PPDU in the multi-AP cooperation process in which it does not participate. This can avoid the first station switching to the NPCA main channel at unnecessary times, thereby not only avoiding the transmission failure of the multi-AP cooperation process in which the first station participates, but also avoiding the waste of the transmission resources of the main channel.

[0338] Optionally, when the first site does not participate in the first multi-AP collaboration process, the first site and the third site can participate in the second multi-AP collaboration process.

[0339] For example, the first site is the first AP, the third site is the third AP, and the first AP and the third AP participate in the second multi-AP collaboration process; or, the first site is the first non-AP STA, the third site is the third non-AP STA, and the first AP associated with the first non-AP STA and the third AP associated with the third non-AP STA participate in the second multi-AP collaboration process.

[0340] At this point, Method 1000 can be understood as follows: when the first station detects the second frame in the first multi-AP cooperation process, the third frame in the second multi-AP cooperation process, or the second PPDU, the first station does not perform NPCA; when the first station detects the first PPDU in the first multi-AP cooperation process, the first station will perform NPCA. The third frame is used to transmit control information in the second multi-AP cooperation process. For example, the third frame may be the ICF in Co-BF, the ICR in Co-BF, the ICF in Co-SR, or the ICR in Co-SR, etc. For details, please refer to the previous description of the second frame. The second PPDU is the downlink data PPDU in the second multi-AP cooperation process; for details, please refer to the description of the first PPDU in Method 1000. In other words, when the first station participates in the second multi-AP cooperation process, neither the control frames in the first multi-AP cooperation process, nor the control frames in the second multi-AP cooperation process, nor the downlink data PPDUs in the second multi-AP cooperation process will trigger the first station to switch to the NPCA primary channel. This ensures that the second multi-AP cooperation process in which the first station participates proceeds normally. However, the downlink data PPDU in the first multi-AP collaboration process will trigger the first site to switch to the NPCA main channel, thus avoiding interference.

[0341] For example, with Figure 11For example, AP1 and AP2 are in the first Co-BF process, with AP1 being the sharing AP and AP2 being the shared AP. AP3 and AP4 are in the second Co-BF process, with AP3 being the sharing AP and AP4 being the shared AP. Non-AP STA1 is associated with AP1, non-AP STA2 with AP2, non-AP STA3 with AP3, and non-AP STA4 with AP4. AP1 and non-AP STA1 are communicating on the main channel, as are AP2 and non-AP STA2. For non-AP STA2 (an example from the first site), since it participates in the first Co-BF process, the Co-BF invitation frame, ICF 1, and downlink data PPDU 1 in the first Co-BF process will not trigger non-AP STA2 to switch to the NPCA main channel, thus ensuring the normal operation of the first multi-AP cooperation process. Similarly, for non-AP STA 4 (another example from the first site), since it participates in the second Co-BF process, the Co-BF invitation frame, ICF 1, and downlink data PPDU 1 in the second Co-BF process will not trigger non-APSTA 4 to switch to the NPCA primary channel, thus ensuring the normal operation of the second multi-AP cooperation process. It should be understood that the Co-BF invitation frame, ICF 1, and downlink data PPDU 1 in the second Co-BF process... Figure 11 Not shown in the image.

[0342] However, for non-AP STA4 (another example of the first site), since it does not participate in the first Co-BF process, downlink data PPDU 1 or downlink data PPDU 2 in the first Co-BF process will trigger non-AP STA4 to switch to the NPCA main channel. For example, at time #1, non-AP STA4 can switch to the NPCA main channel. Similarly, for sites participating in the second Co-BF process, such as AP3, AP4, and non-AP STA3, they will all be triggered by downlink data PPDU 1 or downlink data PPDU 2 in the first Co-BF process to switch to the NPCA main channel, thereby avoiding interference between the first and second multi-AP cooperation processes.

[0343] Optionally, AP3, AP4, non-AP STA3, and non-AP STA4 can switch back to the main channel at the end of downlink data PPDU 2, or at the end of TXOP where the first Co-BF procedure is located, as detailed in S1030a and S1030b below. Figure 11 This illustrates the case where the system switches back to the main channel at the end of downlink data PPDU 2.

[0344] Optionally, as an implementation scenario, when method 1000 includes S1020a, method 1000 further includes: S1030a, based on the end time of the TXOP in which the first multi-AP collaboration process is located, the first station switches from the second main channel to the first main channel.

[0345] Specifically, the handover from the second primary channel to the first primary channel based on the end time of the TXOP where the first multi-AP collaboration process is located can be replaced with: completing the handover from the second primary channel to the first primary channel no later than the end time of the second TXOP. The second TXOP can refer to the TXOP where the first multi-AP collaboration process is located. Specifically, the first site can complete the handover before the end time of the second TXOP, or the end time of the second TXOP and the completion time of the handover from the second primary channel to the first primary channel can be aligned. "Aligned" means approximately aligned; as long as the difference between the end time of the second TXOP and the completion time of the handover of the first primary channel is less than a certain duration, it can be considered aligned.

[0346] Specifically, in this implementation scenario, the first station can switch from the NPCA main channel to the first main channel based on the end time of the TXOP in the first multi-AP collaboration process. In other words, the first station can perform NPCA based on the TXOP length. However, the difference from the NPCA based on TXOP length mentioned earlier is that the timing of starting the switch to the NPCA main channel has changed. Figure 3 For example, if non-AP STA2 is triggered by ICF1 or ICR1, such as when non-AP STA2 switches to the NPCA main channel at time #1, then non-AP STA2 will switch to the NPCA main channel until the entire TXOP ends. In contrast, according to the method of this implementation scenario, non-AP STA2 will not be triggered by ICF1 or ICR1 to trigger NPCA, thus avoiding the situation where the first multi-AP collaboration process cannot proceed normally.

[0347] Figure 12 (a) is an example of this implementation scenario, such as Figure 12 As shown in (a), if station #1 (an example of the first station) is triggered by an ICF or ICR before the Co-BF DL PPDU, and station #1 is not related to this Co-BF transmission, then the time when station #1 starts to switch to the NPCA main channel is after the start time of the Co-BF DL PPDU, and before the TXOP where the Co-BF is located ends, station #1 will switch back to the main channel.

[0348] Optionally, as another implementation scenario, when method 1000 includes S1020a, method 1000 further includes: S1030b, based on the end time of the first PPDU, the first station switches from the second main channel to the first main channel.

[0349] For a detailed description of S1030b, please refer to S730. This implementation scenario can be understood as NPCA based on PPDU length. Since the length of the PPDU in the second frame does not meet the conditions for triggering NPCA based on PPDU length, the first station will not be triggered by NPCA in the second frame, thus avoiding Co-BF transmission failure. The downlink data PPDUs in the first multi-AP collaboration process generally meet the minimum duration threshold for NPCA, and the first station can determine whether to perform NPCA based on the sender of the PPDU.

[0350] Figure 12 (b) is an example of this implementation scenario, such as Figure 12 As shown in (b), if station #1 (an example of the first station) detects an ICF or ICR prior to a Co-BF DL PPDU, then NPCA based on PPDU length is enabled until the Co-BFTXOP ends. Station #1 switches to the NPCA main channel for each Co-BF DL PPDU and switches back to the main channel before the end of each PPDU.

[0351] It should be understood that both implementation scenarios achieve the following effect: if the first site is involved in the first multi-AP collaboration process, it will not perform NPCA (Non-Performance Communication), meaning it will remain on the main channel, ensuring the normal operation of the first multi-AP collaboration process. If the first site is not involved in the first multi-AP collaboration process, it can switch to the NPCA main channel at the start of the data PPDU (Presented PPDU) in the first multi-AP collaboration process. Furthermore, if the first PPDU is not transmitted due to the result of the second frame interaction, the first site will also remain on the main channel, increasing its access opportunities.

[0352] The difference between the two implementation scenarios is that if the first site performs NPCA, the time to switch back to the primary channel differs. The first multi-AP cooperation process may include the transmission of multiple downlink data PPDUs within a TXOP. According to S1030a, the first site will switch back to the primary channel at the end of the TXOP, while according to S1030b, the first site will switch back to the primary channel at the end of the first downlink data PPDU.

[0353] Furthermore, if the first multi-AP collaboration process is a Co-BF measurement process, both implementation scenarios achieve the following effect: during the entire Co-BF measurement phase, non-AP STAs will not trigger NPCA, ensuring the success of the Co-BF measurement. Specifically, in the first implementation scenario, since there is no downlink data PPDU, NPCA will not be triggered. In the second implementation scenario, the Co-BF measurement phase does not have a sufficiently long PPDU, therefore NPCA will not be triggered.

[0354] Optionally, in any of the above implementation scenarios, the first station is a first non-AP STA or a first AP. Before S1010, the method 1000 further includes: the first AP sending second indication information on the first main channel, and correspondingly, the first non-AP STA receiving the second indication information.

[0355] The second indication information is used to indicate the type of NPCA of the non-AP STA associated with the first AP, and the non-AP STA associated with the first AP includes the first non-AP STA.

[0356] Specifically, after determining that a Co-BF or Co-SR agreement has been reached with other APs (such as a third AP), the first AP can restrict NPCA (Non-Performance Regulation) of the first BSS. For example, the first AP can instruct the first BSS station to perform NPCA based solely on PPDU length in at least one frame, such as a beacon frame, probe response frame, or other management frame. This mode is effective for the duration of the Co-BF or Co-BF agreement. Alternatively, if the first AP anticipates that a Co-BF procedure or Co-SCR may occur within one or more beacon intervals, the first AP can instruct the first BSS station to perform NPCA based solely on PPDU length within those beacon intervals in at least one frame, such as a beacon frame, probe response frame, or other management frame. Alternatively, the first AP can inform the first BSS station to enable or disable NPCA based on PPDU length based on the beacon interval where a Co-BF procedure or Co-BF is expected to occur.

[0357] In this process, the first AP and the third AP reach a Co-BF or Co-SR agreement. It can also be said that both the first AP and the third AP participate in the second multi-AP collaboration process, which is a Co-BF process or a Co-BF process.

[0358] Optionally, in method 1000, the scheme of the first AP sending the second indication information can also be implemented separately. Specifically, the first AP can generate the second indication information and send it on the first main channel. The second indication information is used to indicate the type of NPCA for the non-AP STA associated with the first AP. For the station receiving the second indication information (such as the first non-AP STA), it can know the type of NPCA to be performed based on the second indication information. Furthermore, the first station can perform the NPCA based on the PPDU length in method 1000, or it can perform other operations related to or unrelated to NPCA.

[0359] It should be understood that in this application, frames are all MAC layer protocol data units (MPDUs), commonly referred to as MAC frames, which is a MAC layer concept, while PPDUs are a physical layer (PHY) concept. In actual communication, MAC frames are generally encapsulated in PPDUs before being sent. Unless otherwise specified, "frame interaction" can also be understood as "PPDU interaction".

[0360] The above combination Figures 1 to 12 The methods provided in the embodiments of this application have been described. It is understood that, in order to implement the functions in the above embodiments, the first site and the second site include hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should readily recognize that, based on the units and method steps of the various examples described in conjunction with the embodiments disclosed in this application, this application can be implemented in hardware or a combination of hardware and computer software. Whether a certain function is executed in a hardware or computer software-driven hardware manner depends on the specific application scenario and design constraints of the technical solution.

[0361] Figure 13 and Figure 14 This is a schematic diagram of the communication device provided in the embodiments of this application. These communication devices can be used to implement the functions of the first station and the second station in the above method embodiments, and therefore can also achieve the beneficial effects of the above method embodiments. In the embodiments of this application, the communication device can be the first station, or the second station, or it can be a module (such as a chip) applied to the first station or the second station.

[0362] like Figure 13 As shown, the communication device 2000 includes a transceiver unit 2020. Optionally, the communication device 2000 may further include a processing unit 2010. The communication device 2000 is used to implement the above-described... Figure 7 or Figure 10 The method embodiments shown illustrate the functions of the first or second station.

[0363] When the communication device 2000 is used to achieve Figure 7 In the method embodiment shown, the function of the first station is as follows: the transceiver unit 2020 is used to receive the first frame on the first main channel, and the processing unit 2010 is used to switch from the first main channel to the second main channel when the first PPDU is detected in the TXOP where the first frame is located and the first PPDU meets the conditions for triggering NPCA. The second main channel is the NPCA main channel, and the first PPDU is a PPDU sent by the second station or a station associated with the second station. The processing unit 2010 is also used to switch from the second main channel to the first main channel based on the end time of the first PPDU.

[0364] When the communication device 2000 is used to achieve Figure 7 In the method embodiment shown, the function of the second station is as follows: the transceiver unit 2020 is used to: send a first frame on the first main channel, the first frame being used to query the unavailability information of the station associated with the second station, or the first frame being used to carry the unavailability information of the second station.

[0365] When the communication device 2000 is used to achieve Figure 10 In the method embodiment shown, the function of the first station is as follows: the transceiver unit 2020 is used to receive the second frame on the first main channel; the processing unit 2010 is used to switch from the first main channel to the second main channel when the first station does not participate in the first multi-AP cooperation process and the first PPDU is detected to meet the conditions for triggering NPCA, the second main channel is the NPCA main channel, the first PPDU is the downlink data PPDU in the first multi-AP cooperation process, and the BSS to which the second station belongs and the BSS to which the first station belongs are each other's OBSS; or, the processing unit 2010 is used to stay on the first main channel in the TXOP where the first multi-AP cooperation process is located when the first station participates in the first multi-AP cooperation process and the second frame or the first PPDU is detected.

[0366] When the communication device 2000 is used to achieve Figure 10 In the method embodiment shown, the function of the second station is as follows: the transceiver unit 2020 is used to: send a second frame on the first main channel, the second frame being used to transmit control information in the first multi-AP cooperation process.

[0367] For more detailed information on the functions of the transceiver unit 2020 and the processing unit 2010, please refer to the method embodiments described above.

[0368] Optionally, the communication device 2000 may further include a storage unit, which can be used to store program code, program instructions and / or data. The processing unit 2010 can read the instructions and / or data in the storage unit so that the communication device 2000 can implement the aforementioned method embodiments.

[0369] Optionally, the transceiver unit 2020 may include a sending unit and a receiving unit. The sending unit is used to implement the sending operation in the above method embodiment, that is, to execute the sending action of the communication device 2000. The receiving unit is used to implement the receiving operation in the above method embodiment, that is, to execute the receiving action of the communication device 2000.

[0370] It should be noted that the communication device 2000 may include a transmitting unit but not a receiving unit. Alternatively, the communication device 2000 may include a receiving unit but not a transmitting unit. Specifically, it depends on whether the above-described scheme executed by the communication device 2000 includes both transmitting and receiving actions. For a detailed description of the functions performed by the processing unit 2010 and the transceiver unit 2020, please refer to... Figure 7 or Figure 10 The relevant descriptions in the method shown.

[0371] In this application, the transceiver unit can also be called a transceiver module, which includes a sending module and a receiving module, and the storage unit can also be called a storage module.

[0372] like Figure 14 As shown, the communication device 3000 includes a processor 3010 and an interface circuit 3020. The processor 3010 and the interface circuit 3020 are coupled to each other. It is understood that the interface circuit 3020 can be a transceiver or an input / output interface. Optionally, the communication device 3000 may also include a memory 3030 for storing instructions executed by the processor 3010, or storing input data required by the processor 3010 to execute instructions, or storing data generated after the processor 3010 executes instructions. Sometimes, the interface circuit 3020 can also be understood as part of the processor 3010, in which case the communication device 3000 includes the processor 3010.

[0373] When the communication device 3000 is used to implement 7 or Figure 10 In the illustrated method, processor 3010 implements the functions of processing unit 2010, and interface circuit 3020 implements the functions of transceiver unit 2020. For example, when interface circuit 3020 is a transceiver, it may include a transmitter and / or a receiver, respectively, to implement the functions of the transmitting unit and the receiving unit. When interface circuit 3020 is an input / output interface, it may include an output interface and / or an input interface, respectively, to implement the functions of the transmitting unit and the receiving unit.

[0374] When the communication device 3000 is a chip, the chip includes a processor and a transceiver. The processor can be a processing module integrated on the chip, a microprocessor, or an integrated circuit. The transceiver can be an input / output circuit or a communication interface. The sending operation in the above method embodiments can be understood as the chip's output, and the receiving operation in the above method embodiments can be understood as the chip's input. Optionally, when the communication device 3000 is a chip, it may include a memory, such as the memory built into the chip; alternatively, the communication device 3000 may not include a memory, for example, although the chip is connected to a memory, the memory and the chip are independent of each other.

[0375] Furthermore, when the aforementioned communication device is a chip applied to the first (or second) site, the chip implements the functions of the first (or second) site in the above method embodiments. The chip receiving information can be understood as the information being first received by other modules (such as radio frequency modules or antennas) in the first (or second) site, and then sent to the chip by these modules. The chip sending information can be understood as the information being first sent to other modules (such as radio frequency modules or antennas) in the first (or second) site, and then sent by these modules.

[0376] It is understood that the processor in the embodiments of this application can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. A general-purpose processor can be a microprocessor or any conventional processor.

[0377] The method steps in the embodiments of this application can be implemented in hardware or in software instructions executable by a processor. The software instructions can consist of corresponding software modules, which can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, registers, hard disks, portable hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. The storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. Alternatively, the ASIC can reside in a base station or terminal. The processor and storage medium can also exist as discrete components in a base station or terminal.

[0378] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of this application are performed entirely or partially. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user equipment, or other programmable device. The computer program or instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions can be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; it can also be an optical medium, such as a digital video optical disc; or it can be a semiconductor medium, such as a solid-state drive. The computer-readable storage medium may be a volatile or non-volatile storage medium, or may include both types of storage media.

[0379] In the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions of different embodiments are consistent and can be referenced by each other. The technical features of different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0380] In this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or B exists alone, where A and B can be singular or plural. In the textual description of this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship. "Including at least one of A, B, and C" can mean: including A; including B; including C; including A and B; including A and C; including B and C; including A, B, and C.

[0381] In this application, descriptions such as "when," "under the circumstances," "if," and "if" all refer to the device making corresponding actions under certain objective circumstances. They are not time-limited, nor do they require the device to make a judgment action during implementation, nor do they imply any other limitations.

[0382] It should be understood that in the various embodiments of this application, the terms "first," "second," and various numerical designations are merely for descriptive convenience and are not intended to limit the scope of the embodiments of this application. The order of the sequence numbers of the above processes does not imply the order of execution; the execution order of each process should be determined by its function and internal logic.

[0383] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0384] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0385] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0386] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0387] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0388] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0389] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A communication method, characterized in that, Applied to the first site, including: Upon detecting a first Physical Layer Protocol Data Unit (PPDU) and finding that the PPDU meets the conditions for triggering Non-Main Channel Access to NPCA, the system switches from the first main channel to the second main channel, which is the NPCA main channel. The conditions for the first PPDU to meet the conditions for triggering Non-Main Channel Access to NPCA include: When the first PPDU includes N basic service set colors (BSS colors), the N BSS colors are different from the BSS color of the BSS to which the first site belongs, and N is an integer greater than or equal to 2.

2. The method according to claim 1, characterized in that, The N BSS colors are carried in the general signaling U-SIG field of the first PPDU.

3. The method according to claim 1 or 2, characterized in that, N equals 2.

4. The method according to any one of claims 1 to 3, characterized in that, The switching from the first primary channel to the second primary channel includes: After detecting the U-SIG field of the first PPDU, the handover from the first primary channel to the second primary channel begins.

5. The method according to any one of claims 1 to 4, characterized in that, The method further includes: Based on the end time of the TXOP where the first PPDU is located, switch from the second main channel to the first main channel; or, Based on the end time of the first PPDU, the system switches from the second main channel to the first main channel.

6. The method according to any one of claims 1 to 5, characterized in that, The first PPDU is the downlink data PPDU in the first multi-access point (AP) cooperation process. The first multi-AP cooperation process is either the Cooperative Space Reuse (Co-SR) process or the Cooperative Beamforming (Co-BF) process. The N BSS colors include the BSS colors of the basic service set (BSS) to which the sites participating in the first multi-AP cooperation process belong.

7. The method according to any one of claims 1 to 6, characterized in that, The method further includes: Detect the first PPDU.

8. A communication device, characterized in that, include: The processing unit is configured to switch from a first primary channel to a second primary channel, whereby the second primary channel is the NPCA primary channel, upon detecting a first PPDU and the first PPDU meeting the conditions for triggering NPCA, wherein the first PPDU meets the conditions for triggering non-primary channel access to NPCA, including: When the first PPDU includes N basic service set colors (BSS colors), the N BSS colors and the BSS color of the device are all different, where N is an integer greater than or equal to 2.

9. The apparatus according to claim 8, characterized in that, The N BSS colors are carried in the general signaling U-SIG field of the first PPDU.

10. The apparatus according to claim 8 or 9, characterized in that, N equals 2.

11. The apparatus according to any one of claims 8 to 10, characterized in that, The processing unit is specifically used for: After detecting the U-SIG field of the first PPDU, the handover from the first primary channel to the second primary channel begins.

12. The apparatus according to any one of claims 8 to 11, characterized in that, The processing unit is also used for: Based on the end time of the TXOP where the first PPDU is located, switch from the second main channel to the first main channel; or, Based on the end time of the first PPDU, the system switches from the second main channel to the first main channel.

13. The apparatus according to any one of claims 8 to 12, characterized in that, The first PPDU is the downlink data PPDU in the first multi-access point (AP) cooperation process. The first multi-AP cooperation process is either the Cooperative Space Reuse (Co-SR) process or the Cooperative Beamforming (Co-BF) process. The N BSS colors include the BSS colors of the basic service set (BSS) to which the sites participating in the first multi-AP cooperation process belong.

14. The apparatus according to any one of claims 8 to 13, characterized in that, The device further includes: The transceiver unit is used to detect the first PPDU.

15. A communication device, characterized in that, include: A processor coupled to a memory for storing a computer program, the processor for executing the computer program stored in the memory to cause the apparatus to perform the method as described in any one of claims 1 to 7.

16. A computer-readable storage medium, characterized in that, The storage medium stores a computer program or instructions, which, when executed by a communication device, implement the method as described in any one of claims 1 to 7.

17. A computer program product, characterized in that, Includes a computer program that, when run, implements the method as described in any one of claims 1 to 7.

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