Communication method and communication device

Abstract

An embodiment of the present application provides a communication method applicable to a communication system supporting IEEE 802.11 series protocols (such as Wi-Fi 7 and Wi-Fi 8). The method is performed by a first access point belonging to a first BSS. The method includes the steps of: receiving first information from a second access point, the first information indicating a first maximum time length for which the first station transmits a PPDU, the second access point and the first station belonging to the second BSS, and a coverage area of ​​the second BSS overlapping with the coverage area of ​​the first BSS; generating second information, the second information indicating a second maximum time length for which the second station transmits a PPDU, the second maximum time length being less than or equal to the first maximum time length, and the second station belonging to the first BSS; and transmitting the second information. The technical solution of the present application can avoid an AP or STA in an OBSS occupying a channel for a long time, resulting in an inability to perform preemption.

Description

[Technical Field]

[0001] This application claims priority to Chinese Patent Application No. 202310237050.0, entitled "COMMUNICATION METHOD AND COMMUNICATION DEVICE," filed with the State Intellectual Property Office of the People's Republic of China on March 2, 2023, which is incorporated herein by reference in its entirety.

[0002] The present application relates to the field of communications, and more particularly to communication methods and devices. [Background technology]

[0003] IEEE 802.11 is one of the current mainstream wireless access standards and has been widely used in commercial applications over the past decade. Low latency is an important research objective for wireless local area network (WLAN) standards. IEEE 802.11be introduces restricted target wake time (R-TWT) to improve support for low-latency services. R-TWT pre-allocates service periods based on periodic services and gives high access priority to low-latency services during the service periods. Although R-TWT can improve support for low-latency services, next-generation WLAN standards, i.e., ultra-high reliability (UHR), may impose higher requirements for low latency, e.g., ultra-low latency of less than a few milliseconds.

[0004] Preemption is a potential technology for solving the ultra-low latency problem. The principle of preemption is to interrupt the transmission of a currently transmitted non-low latency service, prioritize the transmission of a low latency service, and resume the transmission of the non-low latency service after the transmission of the low latency service is completed. Existing technical solutions mainly consider how to perform preemption in a basic service set (BSS), but do not consider how to prevent overlapping basic service sets (OBSSs) from occupying the channel for a long period of time. Summary of the Invention

[0005] The embodiments of the present application provide a communication method and a communication device to avoid the situation where an access point (AP) or a station (STA) in an OBSS cannot perform preemption because it occupies a channel for a long time. Even when the OBSS occupies the channel, stations and access points in a BSS can have more opportunities to transmit low-latency services. [Means for solving the problem]

[0006] According to a first aspect, a communication method is provided, the method being performed by a first access point or a communication device located at the first access point. The first access point belongs to a first basic service set (BSS). The method includes receiving first information from a second access point, the first information indicating a first maximum length of time for the first station to transmit a physical layer protocol data unit (PPDU), the second access point and the first station belong to the second BSS, a coverage area of ​​the second BSS having an overlapping portion with a coverage area of ​​the first BSS, and the first station supporting preemption; generating second information indicating a second maximum length of time for the second station to transmit a PPDU, the second maximum length of time being less than or equal to the first maximum length of time, the second station belonging to the first BSS, and the second station supporting preemption; and transmitting the second information.

[0007] The technical solution provided in this application takes into account the impact of the OBSS on preemption services. A maximum time period for a station to transmit a PPDU is set, so that even if the OBSS occupies the channel, stations and access points in the BSS can have more opportunities to transmit low-latency services.

[0008] It should be understood that preemption indicates that transmission of a low-latency service is given priority and transmission of a non-low-latency service is resumed after transmission of the low-latency service is completed. The first station and the second station may be non-access point stations (non-AP STAs) that support preemption.

[0009] It should be understood that the coverage area of ​​the second BSS having an overlapping portion with the coverage area of ​​the first BSS indicates that the first BSS and the second BSS are OBSSs of each other, i.e., the OBSS of the first BSS includes the second BSS, and the OBSS of the second BSS includes the first BSS.

[0010] It should be understood that the second information is set by the first access point based on the received first information, and the second maximum time length is equal to or less than the first maximum time length. Since the operation of setting the second information is mutual for APs that are BSSs of each other, all BSSs that support preemption set the second information to the same value, i.e., the minimum value that each AP originally wants to set among the multiple second information.

[0011] For example, the first information and the second information may be preemption limit fields, and the specific names of the fields should not be understood as limitations on the present application.

[0012] It should be understood that for information exchanges with response frames, the preemption limit should include the total time limit for the information exchange. For example, in the case of a data / block acknowledgement (BA) interaction, the sum of the PPDU carrying the data, the PPDU carrying the BA, and the short interframe space (SIFS) between the two cannot exceed the preemption limit.

[0013] In a possible implementation, the first information may be carried by a field in a beacon frame transmitted by the second access point, and the second information may be carried by a field in a beacon frame transmitted by the first access point.

[0014] In relation to the first aspect, in some implementations of the first aspect, the method further includes determining that a basic network allocation vector (basic NAV) of the first access point is set based on a frame transmitted by the second access point or the first station, and ignoring the basic network allocation vector.

[0015] It should be understood that after the first station or second access point in the second BSS obtains a transmission opportunity (TXOP), the second station or first access point in the first BSS sets a basic network allocation vector (basic NAV) based on the received frame transmitted by the first station or second access point in the second BSS. According to the rules of the current standard, a station or access point whose basic NAV value is not equal to 0 is not allowed to actively contend for the channel or transmit data. In this case, if the second station or first access point in the first BSS wants to transmit a low-latency service by preemption, the basic NAV set by the first station or second access point in the second BSS must be ignored. That is, even if the basic NAV value of the second station or first access point in the first BSS is greater than 0, the value is considered to be 0, and preemption is initiated.

[0016] For example, a first access point transmits a PPDU for performing a preemption operation at a first time point, the basic network allocation vector of the first access point is set based on a received frame transmitted by the first station or the second access point in the second BSS, and the basic network allocation vector of the first access point is greater than 0 at the first time point.

[0017] In the technical solution provided in the present application, the first access point is arranged to ignore the basic network allocation vector set by the frame transmitted by the second access point or the first station, so as to ensure that the first access point in the first BSS can initiate preemption when low-latency service data arrives.

[0018] In relation to the first aspect, in some implementations of the first aspect, the method further includes receiving third information from the second access point, the third information indicating a third maximum length of time that the first station is permitted to use the channel continuously after acquiring the channel through contention; generating fourth information, the fourth information indicating a fourth maximum length of time that the second station is permitted to use the channel continuously after acquiring the channel through contention, the fourth maximum length of time being less than or equal to the third maximum length of time; and transmitting the fourth information.

[0019] In a possible implementation, the first information and the third information are carried in the same frame, and the second information and the fourth information are carried in the same frame.

[0020] In a possible implementation, the third information may be carried by a field in a beacon frame transmitted by the second access point, and the fourth information may be carried by a field in a beacon frame transmitted by the first access point.

[0021] For example, the third information and the fourth information may be a transmission opportunity limit (TXOP Limit) field, and the specific names of the fields should not be understood as limitations on the present application.

[0022] It should be understood that the fourth information is set by the first access point based on the received third information, and the fourth maximum time length is equal to or less than the third maximum time length. Since the operation of setting the fourth information is reciprocal for APs that are BSSs of each other, all BSSs that support preemption set the fourth information to the same value, i.e., the minimum value that each AP originally wants to set among the multiple fourth information.

[0023] The technical solution provided in this application takes into account the impact of the OBSS on preemption services. A maximum time period is set for a station to be allowed to continuously use a channel after acquiring it through contention, so that even if the OBSS occupies the channel, stations and access points within the BSS can have more opportunities to transmit low-latency services.

[0024] In relation to the first aspect, in some implementations of the first aspect, the method further includes receiving fifth information from the second access point, the fifth information indicating a group in which the second BSS is located, and determining, based on the fifth information, that the second BSS and the first BSS are in the same group.

[0025] In some possible implementations, the fifth information may be a preemption group field, and the name should not be construed as a limitation to the present application.

[0026] Optionally, the fifth information may include one or more bits. For example, the fifth information may be 1 bit, and the fifth information being set to 1 indicates that the second BSS is participating in a preemption group; otherwise, it indicates that the second BSS is not participating in a preemption group. Alternatively, the fifth information being set to 0 indicates that the second BSS is participating in a preemption group; otherwise, it indicates that the second BSS is not participating in a preemption group. For example, the fifth information may include multiple bits. The fifth information being set to 0 indicates that the second BSS is not participating in any preemption group; and the fifth information not being set to 0 indicates that the second BSS is participating in a specific preemption group. For example, the fifth information being "11" indicates that the second BSS is participating in the third preemption group.

[0027] According to the communication method provided in this embodiment of the present application, the preemption group field is set, so that a BSS that supports preemption can flexibly choose to join or not join a preemption group, thereby controlling the range of access points or stations to perform preemption operations.

[0028] In relation to the first aspect, in some implementations of the first aspect, the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer signal SIG field of the first PPDU, and the first PPDU is a PPDU transmitted by the second access point.

[0029] For example, a PPDU includes three parts: a physical layer frame header, data, and a physical layer extension (PE), and the physical layer frame header includes a physical layer SIG field.

[0030] The fifth information may be carried by a field in the beacon frame transmitted by the second access point, and may be, for example, a preemption element or a UHR operation element.

[0031] In relation to the first aspect, in some implementations of the first aspect, the method further includes a step of transmitting sixth information, wherein the sixth information indicates a BSS located in the same group as the first BSS.

[0032] In a possible implementation, the sixth information may be carried by a field in a beacon frame transmitted by the first access point.

[0033] In the communication method provided in this embodiment of the present application, the first access point autonomously selects an OBSS that is in the same preemption group as the first access point by using the sixth information, so that the method of establishing the preemption group becomes more flexible.

[0034] In relation to the first aspect, in some implementations of the first aspect, the sixth information indicates a color or partial identification information (identity document, ID) of a BSS located in the same group as the first BSS.

[0035] In some possible implementations, the sixth information may be a Preemption BSS Color Bitmap field. For example, the length of the Preemption BSS Color Bitmap field may be 64 bits. Currently, the BSS color is 6 bits, and there may be up to 64 different BSS colors. Therefore, each bit in the 64 bits of the Preemption BSS Color Bitmap field may correspond to one BSS color.

[0036] It should be understood that the preemption BSS color bitmap is a bitmap that indicates the BSS color values ​​used by members of the preemption group to which the first access point belongs. Each bit in the bitmap corresponds to one of 64 BSS colors, with the lowest-numbered bit corresponding to BSS color value 0 and the highest-numbered bit corresponding to BSS color value 63. For example, if a bit in the bitmap is 1, this indicates that at least one BSS using the BSS color value corresponding to the bit is in the same preemption group as the first access point. If a bit in the bitmap is 0, this indicates that no BSS in the preemption group to which the first access point belongs uses the BSS color value corresponding to the bit. The BSS color value 0 corresponds to a reserved bit in the bitmap.

[0037] It should be understood that the length of the Preemption BSS Color Bitmap field may be related to the number of OBSSs. If the number of OBSSs is relatively small, a length of less than 64 bits may be used. The length of the Preemption BSS Color Bitmap field is not specified. This example should not be understood as a limitation on the present application.

[0038] In some possible implementations, the preemption group member field may be a Preemption Partial BSSID Bitmap field. A BSS identity document (BSSID) is 6 bytes, i.e., 48 bits. If the bitmap were to indicate all possible BSSID values ​​in a scanning manner, a large amount of space would be wasted. Therefore, in this embodiment of the present application, some bits in the BSSID indicate BSSs located in the same preemption group as the first access point. For example, the Preemption Partial BSSID Bitmap may be selected as 64 bits, each corresponding to one value in BSSID[39:44], or each corresponding to one value in BSSID[38:43]. It should be understood that A[a:b] is the range of A from the ath bit to the bth bit.

[0039] It should be understood that the Preemption Partial BSSID Bitmap field is a bitmap that indicates a portion of the BSSID values ​​of members located in the same preemption group as the first access point. For example, each bit in the bitmap corresponds to one of 64 possible values ​​of BSSID[39:44], with the lowest-numbered bit corresponding to partial BSSID value 0 and the highest-numbered bit corresponding to partial BSSID value 63. For example, if a bit in the bitmap is 1, this indicates that at least one BSS using the partial BSSID value corresponding to the bit is in the same preemption group as the first access point. If a bit in the bitmap is 0, this indicates that no BSS in the preemption group in which the first access point is located uses the partial BSSID value corresponding to the bit.

[0040] It should be understood that the 64-bit preemption partial BSSID bitmap is merely an example, and this example should not be understood as a limitation on the present application. In a practical application scenario, the preemption partial BSSID bitmap may be selected as a specific length, for example, 32 bits or 16 bits, as needed to accommodate a specific range of BSSIDs.

[0041] In the communication method provided in the present application, the first access point may indicate a BSS in the same preemption group as the first access point by using either the Preemption BSS Color Bitmap field or the Preemption Partial BSSID Bitmap field. Optionally, the first access point may alternatively indicate a BSS in the same preemption group as the first access point by using both the Preemption BSS Color Bitmap field and the Preemption Partial BSSID Bitmap field. This is not a limitation in the present application.

[0042] In the communication method provided in this embodiment of the present application, the first access point autonomously selects an OBSS that is in the same preemption group as the first access point by using the sixth information, so that the method of establishing the preemption group becomes more flexible.

[0043] Referring to the first aspect, in some implementations of the first aspect, the length of the sixth information is 64 bits.

[0044] According to a second aspect, a communication method is provided, the method being performed by a first access point or a communication device disposed at the first access point. The first access point belongs to a first basic service set (BSS). The method includes receiving third information from a second access point, the third information indicating a third maximum length of time a first station is allowed to continuously use the channel after acquiring the channel through contention, the second access point and the first station belong to the second BSS, a coverage area of ​​the second BSS having an overlapping portion with a coverage area of ​​the first BSS, and the first station supports preemption; generating fourth information indicating a fourth maximum length of time a second station is allowed to continuously use the channel after acquiring the channel through contention, the fourth maximum length of time being less than or equal to the third maximum length of time, the second station belongs to the first BSS, and the second station supports preemption; and transmitting the fourth information.

[0045] The technical solution provided in this application takes into account the impact of the OBSS on preemption services. A maximum time period is set for a station to be allowed to continuously use a channel after acquiring it through contention, so that even if the OBSS occupies the channel, stations and access points within the BSS can have more opportunities to transmit low-latency services.

[0046] It should be understood that preemption indicates that transmission of a low-latency service is given priority and transmission of a non-low-latency service is resumed after transmission of the low-latency service is completed. The first station and the second station may be non-access point stations (non-AP STAs) that support preemption.

[0047] It should be understood that the coverage area of ​​the second BSS having an overlapping portion with the coverage area of ​​the first BSS indicates that the first BSS and the second BSS are OBSSs of each other, i.e., the OBSS of the first BSS includes the second BSS, and the OBSS of the second BSS includes the first BSS.

[0048] In a possible implementation, the third information may be carried by a field in a beacon frame transmitted by the second access point, and the fourth information may be carried by a field in a beacon frame transmitted by the first access point.

[0049] For example, the third information and the fourth information may be a transmission opportunity limit (TXOP Limit) field, and the specific names of the fields should not be understood as limitations on the present application.

[0050] It should be understood that the fourth information is set by the first access point based on the received third information, and the fourth maximum time length is equal to or less than the third maximum time length. Since the operation of setting the fourth information is reciprocal for APs that are BSSs of each other, all BSSs that support preemption set the fourth information to the same value, i.e., the minimum value that each AP originally wants to set among the multiple fourth information.

[0051] In relation to the second aspect, in some implementations of the second aspect, the method further includes the steps of receiving first information from a second access point, the first information indicating a first maximum length of time for the first station to transmit a physical layer protocol data unit (PPDU), generating second information, the second information indicating a second maximum length of time for the second station to transmit a PPDU, the second maximum length of time being less than or equal to the first maximum length of time, and transmitting the second information.

[0052] It should be understood that the second information is set by the first access point based on the received first information, and the second maximum time length is equal to or less than the first maximum time length. Since the operation of setting the second information is mutual for APs that are BSSs of each other, all BSSs that support preemption set the second information to the same value, i.e., the minimum value that each AP originally wants to set among the multiple second information.

[0053] For example, the first information and the second information may be preemption limit fields, and the specific names of the fields should not be understood as limitations on the present application.

[0054] It should be understood that for information exchanges with response frames, the preemption limit should include the total time limit for the information exchange. For example, in the case of a data / block acknowledgement (BA) interaction, the sum of the PPDU carrying the data, the PPDU carrying the BA, and the short interframe space (SIFS) between the two cannot exceed the preemption limit.

[0055] In a possible implementation, the first information may be carried by a field in a beacon frame transmitted by the second access point, and the second information may be carried by a field in a beacon frame transmitted by the first access point.

[0056] In a possible implementation, the first information and the third information are carried in the same frame, and the second information and the fourth information are carried in the same frame.

[0057] The technical solution provided in this application takes into account the impact of the OBSS on preemption services. A maximum time period for a station to transmit a PPDU is set, so that even if the OBSS occupies the channel, stations and access points in the BSS can have more opportunities to transmit low-latency services.

[0058] In relation to the second aspect, in some implementations of the second aspect, the method further includes a step of determining that a basic network allocation vector of the first access point is set based on a frame transmitted by the second access point or the first station, and a step of ignoring the basic network allocation vector.

[0059] It should be understood that after the first station or second access point in the second BSS obtains a transmission opportunity (TXOP), the second station or first access point in the first BSS sets a basic network allocation vector (basic NAV) based on the received frame transmitted by the first station or second access point in the second BSS. According to the rules of the current standard, a station or access point whose basic NAV value is not equal to 0 is not allowed to actively contend for the channel or transmit data. In this case, if the second station or first access point in the first BSS wants to transmit a low-latency service by preemption, the basic NAV set by the first station or second access point in the second BSS must be ignored. That is, even if the basic NAV value of the second station or first access point in the first BSS is greater than 0, the value is considered to be 0, and preemption is initiated.

[0060] For example, a first access point transmits a PPDU for performing a preemption operation at a first time point, the basic network allocation vector of the first access point is set based on a received frame transmitted by the first station or the second access point in the second BSS, and the basic network allocation vector of the first access point is greater than 0 at the first time point.

[0061] In the technical solution provided in the present application, the first access point is arranged to ignore the basic network allocation vector set by a frame transmitted by the second access point or the first station, so as to ensure that the second station or the first access point in the first BSS can initiate preemption when low-latency service data arrives.

[0062] In relation to the second aspect, in some implementations of the second aspect, the method further includes a step of receiving fifth information from the second access point, the fifth information indicating a group in which the second BSS is located, and a step of determining, based on the fifth information, that the second BSS and the first BSS are in the same group.

[0063] In some possible implementations, the fifth information may be a preemption group field, and the name should not be construed as a limitation to the present application.

[0064] Optionally, the fifth information may include one or more bits. For example, the fifth information may be 1 bit, and the fifth information being set to 1 indicates that the second BSS is participating in a preemption group; otherwise, it indicates that the second BSS is not participating in a preemption group. Alternatively, the fifth information being set to 0 indicates that the second BSS is participating in a preemption group; otherwise, it indicates that the second BSS is not participating in a preemption group. For example, the fifth information may include multiple bits. The fifth information being set to 0 indicates that the second BSS is not participating in any preemption group; and the fifth information not being set to 0 indicates that the second BSS is participating in a specific preemption group. For example, the fifth information being "11" indicates that the second BSS is participating in the third preemption group.

[0065] According to the communication method provided in this embodiment of the present application, the preemption group field is set, so that a BSS that supports preemption can flexibly choose to join or not join a preemption group, thereby controlling the range of access points or stations to perform preemption operations.

[0066] In relation to the second aspect, in some implementations of the second aspect, the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer signal SIG field of the first PPDU, and the first PPDU is a PPDU transmitted by the second access point.

[0067] For example, a PPDU includes three parts: a physical layer frame header, data, and a physical layer extension (PE), and the physical layer frame header includes a physical layer SIG field.

[0068] The fifth information may be carried by a field in the beacon frame transmitted by the second access point, and may be, for example, a preemption element or a UHR operation element.

[0069] In relation to the second aspect, in some implementations of the second aspect, the method further includes a step of transmitting sixth information, wherein the sixth information indicates a BSS located in the same group as the first BSS.

[0070] In a possible implementation, the sixth information may be carried by a field in a beacon frame transmitted by the first access point.

[0071] In the communication method provided in this embodiment of the present application, the first access point autonomously selects an OBSS that is in the same preemption group as the first access point by using the sixth information, so that the method of establishing the preemption group becomes more flexible.

[0072] In relation to the second aspect, in some implementations of the second aspect, the sixth information indicates a color or a fractional ID of a BSS located in the same group as the first BSS.

[0073] In some possible implementations, the sixth information may be a Preemption BSS Color Bitmap field. For example, the length of the Preemption BSS Color Bitmap field may be 64 bits. Currently, the BSS color is 6 bits, and there may be up to 64 different BSS colors. Therefore, each bit in the 64 bits of the Preemption BSS Color Bitmap field may correspond to one BSS color.

[0074] It should be understood that the preemption BSS color bitmap is a bitmap that indicates the BSS color values ​​used by members of the preemption group to which the first access point belongs. Each bit in the bitmap corresponds to one of 64 BSS colors, with the lowest-numbered bit corresponding to BSS color value 0 and the highest-numbered bit corresponding to BSS color value 63. For example, if a bit in the bitmap is 1, this indicates that at least one BSS using the BSS color value corresponding to the bit is in the same preemption group as the first access point. If a bit in the bitmap is 0, this indicates that no BSS in the preemption group to which the first access point belongs uses the BSS color value corresponding to the bit. The BSS color value 0 corresponds to a reserved bit in the bitmap.

[0075] It should be understood that the length of the Preemption BSS Color Bitmap field may be related to the number of OBSSs. If the number of OBSSs is relatively small, a length of less than 64 bits may be used. The length of the Preemption BSS Color Bitmap field is not specified. This example should not be understood as a limitation on the present application.

[0076] In some possible implementations, the preemption group member field may be a Preemption Partial BSSID Bitmap field. A BSS identity document (BSSID) is 6 bytes, i.e., 48 bits. If the bitmap were to indicate all possible BSSID values ​​in a scanning manner, a large amount of space would be wasted. Therefore, in this embodiment of the present application, some bits in the BSSID indicate BSSs located in the same preemption group as the first access point. For example, the Preemption Partial BSSID Bitmap may be selected as 64 bits, each corresponding to one value in BSSID[39:44], or each corresponding to one value in BSSID[38:43]. It should be understood that A[a:b] is the range of A from the ath bit to the bth bit.

[0077] It should be understood that the Preemption Partial BSSID Bitmap field is a bitmap that indicates a portion of the BSSID values ​​of members located in the same preemption group as the first access point. For example, each bit in the bitmap corresponds to one of 64 possible values ​​of BSSID[39:44], with the lowest-numbered bit corresponding to partial BSSID value 0 and the highest-numbered bit corresponding to partial BSSID value 63. For example, if a bit in the bitmap is 1, this indicates that at least one BSS using the partial BSSID value corresponding to the bit is in the same preemption group as the first access point. If a bit in the bitmap is 0, this indicates that no BSS in the preemption group in which the first access point is located uses the partial BSSID value corresponding to the bit.

[0078] It should be understood that the 64-bit preemption partial BSSID bitmap is merely an example, and this example should not be understood as a limitation on the present application. In a practical application scenario, the preemption partial BSSID bitmap may be selected as a specific length, for example, 32 bits or 16 bits, as needed to accommodate a specific range of BSSIDs.

[0079] In the communication method provided in the present application, the first access point may indicate a BSS in the same preemption group as the first access point by using either the Preemption BSS Color Bitmap field or the Preemption Partial BSSID Bitmap field. Optionally, the first access point may alternatively indicate a BSS in the same preemption group as the first access point by using both the Preemption BSS Color Bitmap field and the Preemption Partial BSSID Bitmap field. This is not a limitation in the present application.

[0080] In the communication method provided in this embodiment of the present application, the first access point autonomously selects an OBSS that is in the same preemption group as the first access point by using the sixth information, so that the method of establishing the preemption group becomes more flexible.

[0081] Referring to the second aspect, in some implementations of the second aspect, the sixth information has a length of 64 bits.

[0082] According to a third aspect, there is provided a communication method, the communication method being performed by a second access point or a communication device disposed at the second access point, the second access point belonging to a second BSS, the method including: transmitting first information to the first access point, the first access point belonging to the first BSS, the first information indicating a first maximum length of time for a first station to transmit a physical layer protocol data unit (PPDU), the second access point and the first station belonging to the second BSS, a coverage area of ​​the second BSS having an overlapping portion with the coverage area of ​​the first BSS, and the first station supporting preemption; and receiving second information from the first access point, the second information indicating a second maximum length of time for a second station to transmit a PPDU, the second maximum length of time being less than or equal to the first maximum length of time, the second station belonging to the first BSS, and the second station supporting preemption.

[0083] In relation to the third aspect, in some implementations of the third aspect, the method further includes the steps of: transmitting third information to the first access point, the third information indicating a third maximum length of time that the first station is permitted to use the channel continuously after acquiring the channel through contention; and receiving fourth information from the first access point, the fourth information indicating a fourth maximum length of time that the second station is permitted to use the channel continuously after acquiring it through contention, the fourth maximum length of time being less than or equal to the third maximum length of time.

[0084] In relation to the third aspect, in some implementations of the third aspect, the method further includes a step of transmitting fifth information, wherein the fifth information indicates a group in which the second BSS is located.

[0085] In relation to the third aspect, in some implementations of the third aspect, the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer SIG field of the first PPDU, and the first PPDU is a PPDU transmitted by the second access point.

[0086] In relation to the third aspect, in some implementations of the third aspect, the method further includes a step of receiving sixth information from the first access point, wherein the sixth information indicates a BSS located in the same group as the first BSS.

[0087] In relation to the third aspect, in some implementations of the third aspect, the sixth information indicates a color or a fractional ID of a BSS located in the same group as the first BSS.

[0088] In relation to the third aspect, in some implementations of the third aspect, the sixth information has a length of 64 bits.

[0089] The beneficial effects of the third aspect or any one of the possible embodiments of the third aspect correspond to the beneficial effects of the first aspect or any one of the possible embodiments of the first aspect, and will not be described in detail again.

[0090] According to a fourth aspect, there is provided a communication method, performed by a second station or a communication device disposed in the second station, where the second station belongs to a first BSS. The method further includes receiving fifth information from a second access point, the fifth information indicating a group in which the second BSS is located, a coverage area of ​​the second BSS having an overlapping portion with a coverage area of ​​the first BSS, and the second access point belonging to the second BSS; and determining, based on the fifth information, that the second BSS and the first BSS are in the same group.

[0091] It should be understood that the coverage area of ​​the second BSS having an overlapping portion with the coverage area of ​​the first BSS indicates that the first BSS and the second BSS are OBSSs of each other, i.e., the OBSS of the first BSS includes the second BSS, and the OBSS of the second BSS includes the first BSS.

[0092] In some possible implementations, the fifth information may be a preemption group field, and the name should not be construed as a limitation to the present application.

[0093] Optionally, the fifth information may include one or more bits. For example, the fifth information may be 1 bit, and the fifth information being set to 1 indicates that the second BSS is participating in a preemption group; otherwise, it indicates that the second BSS is not participating in a preemption group. Alternatively, the fifth information being set to 0 indicates that the second BSS is participating in a preemption group; otherwise, it indicates that the second BSS is not participating in a preemption group. For example, the fifth information may include multiple bits. The fifth information being set to 0 indicates that the second BSS is not participating in any preemption group; and the fifth information not being set to 0 indicates that the second BSS is participating in a specific preemption group. For example, the fifth information being "11" indicates that the second BSS is participating in the third preemption group.

[0094] According to the communication method provided in this embodiment of the present application, the preemption group field is set, so that a BSS that supports preemption can flexibly choose to join or not join a preemption group, thereby controlling the range of access points or stations to perform preemption operations.

[0095] In relation to the fourth aspect, in some implementations of the fourth aspect, the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer SIG field of the first PPDU, and the first PPDU is a PPDU transmitted by the second access point.

[0096] The fifth information may be carried by a field in the beacon frame transmitted by the second access point, and may be, for example, a preemption element or a UHR operation element.

[0097] In relation to the fourth aspect, in some implementations of the fourth aspect, the method further includes receiving seventh information, the seventh information indicating whether the second access point supports preemption, and determining that the second access point supports preemption based on the seventh information.

[0098] It should be understood that before performing preemption to transmit a low-latency service, the second station in the first BSS needs to first determine that the second access point supports preemption. For example, the seventh information may be carried in a beacon frame transmitted by the second access point, and the second station may analyze the beacon frame transmitted by the second access point to determine that the second access point supports the preemption mechanism. Optionally, the first access point in the first BSS may broadcast a list of all BSSs that support preemption, and the second station learns that the second access point supports preemption by using the broadcast list.

[0099] In relation to the fourth aspect, in some implementations of the fourth aspect, the seventh information is carried by a field in a beacon frame transmitted by the first access point or the second access point, and the first access point belongs to the first BSS.

[0100] In relation to the fourth aspect, in some implementations of the fourth aspect, the method further includes a step of determining that a basic network allocation vector of the second station is set based on a frame transmitted by the second access point or the first station, where the first station belongs to the second BSS and supports preemption, and a step of ignoring the basic network allocation vector.

[0101] It should be understood that after the first station or second access point in the second BSS obtains a transmission opportunity (TXOP), the second station or first access point in the first BSS sets a basic network allocation vector (basic NAV) based on the received frame transmitted by the first station or second access point in the second BSS. According to the rules of the current standard, a station or access point whose basic NAV value is not equal to 0 is not allowed to actively contend for the channel or transmit data. In this case, if the second station or first access point in the first BSS wants to transmit a low-latency service by preemption, the basic NAV set by the first station or second access point in the second BSS must be ignored. That is, even if the basic NAV value of the second station or first access point in the first BSS is greater than 0, the value is considered to be 0, and preemption is initiated.

[0102] For example, the second station transmits a PPDU for performing a preemption operation at a second time point, the basic network allocation vector of the second station is set based on a received frame transmitted by the first station or the second access point in the second BSS, and the basic network allocation vector of the second station is greater than 0 at the second time point.

[0103] In the technical solution provided in the present application, the second station is configured to ignore the basic network allocation vector set by the second access point or the frame transmitted by the first station, so as to ensure that the second station in the first BSS can initiate preemption when low-latency service data arrives.

[0104] According to a fifth aspect, there is provided a communications device, comprising a module or unit configured to perform the method of the first aspect or any one of the possible implementations of the first aspect.

[0105] According to a sixth aspect, there is provided a communications device, comprising: a processor. The processor may be coupled to a memory and configured to execute instructions from the memory to perform a method according to the first aspect or any one of the possible implementations of the first aspect. Optionally, the communications device further comprises the memory. Optionally, the communications device further comprises a communications interface. The processor is coupled to the communications interface and controls the communications interface to perform communications with another network element.

[0106] In one embodiment, the communication device is an access point. When the communication device is an access point, the communication interface may be a transceiver or an input / output interface.

[0107] In another embodiment, the communication device is a chip configured in an access point.When the communication device is a chip configured in an access point, the communication interface may be an input / output interface.

[0108] Optionally, the transceiver may be a transceiver circuit. Optionally, the input / output interface may be an input / output circuit.

[0109] According to a seventh aspect, there is provided a communications device, comprising a module or unit configured to perform a method according to the second aspect or any one of the possible implementations of the second aspect.

[0110] According to an eighth aspect, there is provided a communications device, comprising: a processor. The processor may be coupled to a memory and configured to execute instructions from the memory to perform a method according to the second aspect or any one of the possible implementations of the second aspect. Optionally, the communications device further comprises the memory. Optionally, the communications device further comprises a communications interface. The processor is coupled to the communications interface and controls the communications interface to perform communications with another network element.

[0111] In one embodiment, the communication device is an access point. When the communication device is an access point, the communication interface may be a transceiver or an input / output interface.

[0112] In another embodiment, the communication device is a chip configured in an access point.When the communication device is a chip configured in an access point, the communication interface may be an input / output interface.

[0113] Optionally, the transceiver may be a transceiver circuit. Optionally, the input / output interface may be an input / output circuit.

[0114] According to a ninth aspect, there is provided a communications device, comprising a module or unit configured to perform a method according to the third aspect or any one of the possible implementations of the third aspect.

[0115] According to a tenth aspect, there is provided a communications device, the communications device including a processor. The processor may be coupled to a memory and configured to execute instructions in the memory to perform a method according to the third aspect or any one of the possible implementations of the third aspect. Optionally, the communications device further includes the memory. Optionally, the communications device further includes a communications interface. The processor is coupled to the communications interface and controls the communications interface to perform communications with another network element.

[0116] In one embodiment, the communication device is an access point. When the communication device is an access point, the communication interface may be a transceiver or an input / output interface.

[0117] In another embodiment, the communication device is a chip configured in an access point.When the communication device is a chip configured in an access point, the communication interface may be an input / output interface.

[0118] Optionally, the transceiver may be a transceiver circuit. Optionally, the input / output interface may be an input / output circuit.

[0119] According to an eleventh aspect, there is provided a communications device, comprising a module or unit configured to perform a method according to the fourth aspect or any one of the possible implementations of the fourth aspect.

[0120] According to a twelfth aspect, there is provided a communications device, the communications device including a processor. The processor may be coupled to a memory and configured to execute instructions in the memory to perform a method according to the fourth aspect or any one of the possible implementations of the fourth aspect. Optionally, the communications device further includes the memory. Optionally, the communications device further includes a communications interface. The processor is coupled to the communications interface and controls the communications interface to perform communications with another network element.

[0121] In one embodiment, the communication device is a station. When the communication device is a station, the communication interface may be a transceiver or an input / output interface.

[0122] In another embodiment, the communication device is a chip implemented in the station.When the communication device is a chip implemented in the station, the communication interface may be an input / output interface.

[0123] Optionally, the transceiver may be a transceiver circuit. Optionally, the input / output interface may be an input / output circuit.

[0124] According to a thirteenth aspect, there is provided a computer program product, the computer program product including a computer program (also called code or instructions), which, when executed, enables a computer to carry out a method according to any one of the first to fourth aspects and possible implementations thereof.

[0125] According to a fourteenth aspect, there is provided a computer-readable medium having stored thereon a computer program (also called code or instructions), which, when executed on a computer, enables the computer to perform a method according to any one of the first to fourth aspects and possible implementations thereof.

[0126] According to a fifteenth aspect, there is provided a communication system. The communication system includes a first access point, a second access point, and / or a second station. The first access point is configured to perform a method according to any one of the first and second aspects or possible implementations of the first and second aspects. The second access point is configured to perform a method according to the third aspect or any one of possible implementations of the third aspect. The second station is configured to perform a method according to the fourth aspect or any one of possible implementations of the fourth aspect. [Brief explanation of the drawings]

[0127] [Figure 1] 1 is a diagram of the basic architecture of IEEE 802.11 according to the present application. [Figure 2] FIG. 1 is a diagram of an application scenario according to an embodiment of the present application. [Figure 3] 1 is a diagram of a communication device according to an embodiment of the present application; [Figure 4] FIG. 2 is a diagram of an EDCA parameter set element structure according to one embodiment of the present application. [Figure 5] FIG. 2 is a diagram of a structure of a preemption EDCA parameter set element according to one embodiment of the present application. [Figure 6] 1 is a schematic flowchart of a communication method according to an embodiment of the present application; [Figure 7] FIG. 1 is a diagram of another application scenario according to an embodiment of the present application. [Figure 8] 1 is a block diagram of a communication device according to an embodiment of the present application; [Figure 9] 1 is a block diagram of a communication device according to an embodiment of the present application; DETAILED DESCRIPTION OF THE INVENTION

[0128] The following describes the technical solutions of the embodiments in this application with reference to the accompanying drawings. Obviously, the described embodiments are only a part, but not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative efforts shall fall within the protection scope of this application.

[0129] In the embodiments of this application, terms such as "exemplary," "for example," and the like are used to provide an example, illustration, or explanation. Any embodiment or design scheme described in this application as an "example" should not be described as preferred or having more advantages than another embodiment or design scheme. Rather, the term "example" is intended to present a concept in a particular way.

[0130] The service scenarios described in the embodiments of the present application are intended to more clearly explain the technical solutions in the embodiments of the present application, but do not constitute limitations on the technical solutions provided in the embodiments of the present application. Those skilled in the art may know that as new service scenarios emerge, the technical solutions provided in the embodiments of the present application can also be applied to similar technical problems.

[0131] It should be noted that a "field" in this application may be a part of general information, and a "field" may be referred to as a "field," "field," etc. In addition, the names of fields in this application are merely examples, and may be named differently in a particular embodiment. This is not specifically limited in this application.

[0132] In this application, "at least one" means one or more, and "plurality" means two or more. The term "and / or" describes an association relationship for describing related objects and indicates that three relationships may exist. For example, A and / or B may represent the following cases: when only A is present, when both A and B are present, and when only B is present, in which case A and B may be singular or plural. The character " / " generally indicates an "or" relationship between related objects. "At least one of the following items (moieties)" or similar expressions refers to any combination of these items, including any combination of one item (moiety) or multiple items (moieties). For example, at least one item (moiety) of a, b, or c may refer to a, b, c, a and b, a and c, b and c, or a, b, and c, where a, b, and c may be singular or plural.

[0133] IEEE 802.11 is one of the current mainstream wireless access standards and has been widely used in commercial applications over the past decade. Figure 1 is a diagram of the basic architecture of IEEE 802.11 according to the present application. Access points (AP) 1 and AP 2 provide wired or wireless access to the Internet, and each AP is associated with multiple stations (STAs). As shown in Figure 1, AP 1 is associated with STAs 1 to 3, and AP 2 is associated with STAs 4 to 6. Uplink and downlink wireless communications are performed between the APs and the associated STAs according to the IEEE 802.11 protocol.

[0134] Low latency is an important research objective for wireless local area network (WLAN) standards. IEEE 802.11be introduced restricted target wake time (R-TWT) to improve support for low-latency services. R-TWT pre-allocates service periods based on periodic services and gives high access priority to low-latency services during the service periods. While R-TWT can improve support for low-latency services, next-generation WLAN standards, i.e., ultra-high reliability (UHR), may impose higher requirements for low latency, e.g., ultra-low latency of less than a few milliseconds. Such ultra-low latency requirements exist in several practical application scenarios, such as augmented reality (AR), virtual reality (VR), industrial Internet of Things (IoT), and telemedicine, but current WLAN standards cannot meet them. Therefore, a new low-latency mechanism is urgently needed to solve this problem.

[0135] Preemption is a potential technology for solving the ultra-low latency problem. The principle of preemption is to interrupt the transmission of a currently transmitted non-low latency service, prioritize the transmission of a low latency service, and resume the transmission of the non-low latency service after the transmission of the low latency service is completed. It should be understood that low latency and non-low latency services are relative terms. Although non-low latency services may also have latency requirements, the latency requirements of non-low latency services are higher than those of low latency services. Existing technical solutions mainly consider how to perform preemption in a basic service set (BSS), but do not consider how to prevent overlapping basic service sets (OBSSs) from occupying the channel for a long period of time.

[0136] In order to facilitate understanding of the technical solutions of the present application, the following provides a brief description of related concepts or related technologies in the present application.

[0137] 1. Enhanced distributed channel access (EDCA): A channel contention mechanism defined by Wi-Fi multimedia (WMM). This mechanism allows higher priority packets to be transmitted first and occupy more bandwidth.

[0138] 2. Access Category (AC): WMM defines four access categories with their own priority queues. These queues are classified in order of decreasing priority as AC-VO (voice queue), AC-VI (video queue), AC-BE (best effort queue), and AC-BK (background queue). Packets in queues with higher priority have a higher ability to preempt the channel.

[0139] 3. Channel Access: Wireless local area network (WLAN) systems operate in unlicensed frequency bands. Wireless channels in wireless local area networks are shared. Before transmission, channel access must first be performed. Before a station needs to transmit a wireless frame, it must first listen to see if another station is transmitting. If the channel listening result is busy, transmission is temporarily suspended until the channel becomes idle. After the channel becomes idle, random backoff must be further performed before data transmission to address collisions between multiple potential transmitting stations through random backoff. After the random backoff process in the idle state of the channel is completed, the station can transmit a wireless frame. Before data transmission, a short control frame, such as a request to send (RTS) frame or a clear to send (CTS) frame, may also be exchanged with the current station to further reduce throughput loss caused by collisions. After a short frame exchange collision occurs, the transmitting station can know that a collision has occurred as soon as possible and therefore can access the channel again after performing random backoff again. This avoids direct transmission of a long data frame causing transmission failure of the entire data frame when a collision occurs.

[0140] 4. Network Allocation Vector (NAV) Setting: In a WLAN system, sensing must be performed before channel access is performed. Sensing includes physical carrier sensing and virtual carrier sensing. Physical carrier sensing is performed by sensing the energy on the channel and signal of the WLAN radio frame. If the received energy or strength of the received WLAN radio frame is below a threshold, the physical carrier sense is idle; otherwise, the physical carrier sense is busy. Virtual carrier sensing is performed by setting the NAV. The NAV is maintained. When the value of the NAV is not 0, the virtual carrier sense is busy; when the NAV value is 0, the virtual carrier sense is idle. Generally, a station is allowed to access the channel to transmit a radio frame only when both the physical carrier sense and the virtual carrier sense are idle. In early WLAN systems, a station has only one NAV. After successfully receiving a radio frame, the station can update the NAV based on information about the duration field in the radio frame. When the destination address of the received frame is the medium access control (MAC) address of the received frame, the station does not update its NAV. For another radio frame, if the value of the Duration field in the radio frame is greater than the station's current NAV value, the NAV is updated based on the value of the Duration field. The NAV mechanism can effectively solve the collision problem caused by hidden nodes. A hidden node is a station that is not within the signal coverage area of ​​the transmitting station but whose transmission may interfere with the receiving station. In the process of transmitting a radio frame by the transmitting station, the hidden node cannot detect the transmission of the transmitting station and therefore also transmits the radio frame simultaneously. As a result, the receiving station cannot correctly receive the radio frame due to the interference.By using virtual carrier sensing, after successfully contending for the channel, the transmitting station can first exchange short frames with the receiving station, and NAVs are set for the transmitting station and non-target stations around the receiving station based on the Duration fields of the two exchanged short frames. Thus, it is guaranteed that hidden nodes will no longer contend for the channel or transmit radio frames within the time protected by NAV. This period protected by NAV is usually called a transmission opportunity (TXOP).

[0141] 5. Dueling NAV: The IEEE 802.11ax standard introduces two NAVs for precise management. One is called the intra-BSS NAV and the other is called the basic NAV. The intra-BSS NAV is updated based on the intra-BSS PPDU, while the basic NAV is updated based on the inter-BSS PPDU or a PPDU that cannot be distinguished between intra-BSS and inter-BSS. An inter-BSS PPDU is simply a PPDU transmitted from a station outside the current BSS, while an intra-BSS PPDU is simply a PPDU transmitted from a station within the current BSS. For specific methods for distinguishing between inter-BSS PPDUs and intra-BSS PPDUs, please refer to the IEEE 802.11ax standard and will not be described in detail in this application. A station that is not the transmit opportunity holder (TXOP holder) updates its intra-BSS NAV if and only if the received frame satisfies all of the following conditions: (1) the received frame is an intra-BSS PPDU, (2) the value of the duration field of the received frame is greater than the station's current intra-BSS NAV value, and (3) the destination address of the received frame is not the station's MAC address, or the received frame does not trigger the station to respond immediately, or the receiving station is a trigger frame. A station updates its basic NAV if and only if the received frame satisfies all of the following conditions: (1) the received frame is an inter-BSS PPDU, or it is indistinguishable between an intra-BSS PPDU and an inter-BSS PPDU, (2) the value of the duration field of the received frame is greater than the station's current basic NAV value, and (3) the destination address of the received frame is not the station's MAC address. When both the intra-BSS NAV value and the basic NAV value are equal to 0, the virtual carrier sense is idle. In this case, the station can perform channel contention.When a station is triggered to make an immediate response by its associated AP, the station can only do so if the station's physical carrier sense is idle and the basic NAV value is 0. If the basic NAV value is not 0, no response can be returned even if the physical carrier sense result is idle.

[0142] The technical solutions provided in the embodiments of the present application may be applicable to wireless local area networks (WLANs) and next-generation WLAN standard UHR scenarios. For example, the technical solutions may be applicable to IEEE 802.11 system series standards, including, but not limited to, the 802.11a / b / g standard, the 802.11n standard, the 802.11ac standard, the 802.11ax standard, or next-generation standards, such as the 802.11be standard, Wi-Fi 7, or extremely high throughput (EHT), such as the next-generation standard of 802.11be, Wi-Fi 8, or next-generation standards. Currently, WLANs use the IEEE 802.11 series as their standard.

[0143] A WLAN may include multiple basic service sets (BSSs). Network nodes within a BSS are stations (STAs). STAs include access point (AP) stations (APs) and non-access point stations (non-AP STAs). Each BSS may include one AP and multiple non-AP STAs associated with the AP.

[0144] Although the embodiments of the present application are primarily described using WLAN networks, particularly networks to which the IEEE 802.11 system standard is applied as an example, those skilled in the art will readily understand that aspects of the embodiments of the present application can be extended to other networks using various standards or protocols, such as Bluetooth, ZigBee, random phase multiple access (RPMA), high performance radio local area networks (HIPERLAN), wide area networks (WAN), and personal area networks (PAN), or other networks now known or later developed. Therefore, various aspects provided in the embodiments of the present application are applicable to any suitable wireless network, regardless of the coverage area and wireless access protocol used.

[0145] The embodiments of the present application may be further applicable to a wireless local area network system, an internet of things (IoT) network, or a vehicle-to-vehicle (V2X) network. Of course, the embodiments of the present application may be further applicable to other possible communication systems, such as a long term evolution (LTE) system, an LTE frequency division duplex (FDD) system, an LTE time division duplex (TDD) system, a universal mobile telecommunication system (UMTS), a worldwide interoperability for microwave access (WiMAX) communication system, a fifth generation (5G) communication system, and a future sixth generation (6G) communication system.

[0146] The communication system applicable to the present application is only an example for explanation, and the communication system applicable to the present application is not limited thereto, which is described here only once and will not be described in detail again below.

[0147] APs are also called wireless access points, hotspots, etc. APs are access points for mobile users to access wired networks and are primarily deployed within homes, buildings, and campuses with a typical coverage radius of tens to hundreds of meters. Of course, APs may also be deployed outdoors. APs are equivalent to bridges connecting wired and wireless networks. The primary function of an AP is to connect wireless network clients to each other and then connect the wireless network to Ethernet. Specifically, an AP may be a terminal device or a network device with a wireless fidelity (Wi-Fi) chip. An AP may be a device that supports any one of the aforementioned WLAN or IEEE 802.11 system series standards. For example, an AP may be an AP device such as a communication server, router, switch, or bridge.

[0148] The non-AP STA may be a wireless communication chip, a wireless sensor, or a wireless communication terminal, such as a mobile phone supporting Wi-Fi communication, a tablet computer supporting Wi-Fi communication, a laptop computer supporting Wi-Fi communication, a set-top box supporting Wi-Fi communication, a smart TV supporting Wi-Fi communication, a smart wearable device supporting Wi-Fi communication, an in-vehicle communication device supporting Wi-Fi communication, or a computer supporting Wi-Fi communication. For example, the station may support any one of the aforementioned WLAN or IEEE 802.11 system series standards. Optionally, the station supports multiple WLAN standards, such as 802.11ac, 802.11n, 802.11g, 802.11b, and 802.11a.

[0149] In 802.11ax, a BSS color is introduced as an identifier of the BSS, which is used to help a receiving STA identify the source of a received PPDU, for example, from the local BSS or from an overlapped basic service set (OBSS), so that the STA can use spatial multiplexing channel access mechanisms or save power.

[0150] The High Efficiency Signal field (HE-SIG) in the PPDU includes a BSS color field (currently specified as 6 bits; that is, the available BSS color values ​​are integers ranging from 0 to 63) that indicates the BSS color of the transmitted frame. Generally, the BSS color is set by the AP. After selecting a BSS color for the local BSS, the AP notifies all STAs of the local BSS of the selected BSS color value. When transmitting a PPDU, all STAs of the BSS use the BSS color; that is, the value of the BSS color field is set to that BSS color. Generally, one BSS has only one BSS color. Different APs set different BSS colors. Theoretically, different BSSs have different BSS colors. Therefore, after receiving a PPDU, a STA can determine whether the received PPDU is from the local BSS or an OBS by reading the BSS color field.

[0151] FIG. 2 is a diagram of an application scenario according to one embodiment of the present application.

[0152] 2, BSS 1 includes AP 101, STA 103, and STA 104. BSS 2 includes AP 102 and STA 105. STA 104, AP 101, and AP 102 are located in the overlapping area of ​​the coverage areas of AP 101 and AP 102. BSS 1 and BSS 2 are each other's OBSS, i.e., the OBSS of BSS 1 includes BSS 2, and the OBSS of BSS 2 includes BSS 1.

[0153] In the conventional technical solutions, the main focus is on how to perform preemption within a BSS, but the problem of how to prevent an OBSS from occupying the channel for a long time is not considered. For example, AP 102 may occupy the channel for a long time. Because AP 101, STA 104, STA 103, and AP 102 are located in different BSSs, AP 101, STA 104, and STA 103 cannot perform preemption.

[0154] 3 is a diagram of a communication device according to one embodiment of the present application. The communication device may include one or more of the following components: a processor 310, a transmitter 320, a memory 330, a receiver 340, a signal detector 350, a digital signal processor 360, and a user interface 370. It should be understood that the communication device may include only some of the modules shown in the figure. For example, the communication device includes the processor 310 and the memory 330. In some possible implementations, the communication device may be an AP or a non-AP STA.

[0155] In an embodiment of the present application, a low-latency service is a service that must meet its latency requirement by using a preemption mechanism. Generally, the latency requirement of a service is very high, at the millisecond level. A non-low-latency service may also have a latency requirement, which is lower than that of a low-latency service. A non-low-latency service, such as a file copy, may also have a very long latency tolerance, i.e., no latency requirement. It should be understood that a low-latency service may be a service whose latency requirement is less than a preset time threshold, and a non-low-latency service may be a service whose latency requirement is greater than a preset time threshold or no latency requirement.

[0156] It should be understood that the two services in the embodiments of the present application may also be referred to as a low-latency service and a high-latency service, a low-latency service and a relatively low-latency service, etc. The specific names should not be understood as limitations on the present application. For ease of explanation, the present application collectively uses the low-latency service and the non-low-latency service.

[0157] The method provided in this application is implemented for a PPDU-based preemption mechanism. In the PPDU-based preemption mechanism, non-low latency services are divided into several short PPDUs for sequential transmission. If a new low latency service packet arrives during the short PPDU transmission process, the low latency service packet is transmitted first after the short PPDU transmission is completed, and the remaining non-low latency service packets are transmitted after the low latency service packet transmission is completed. The method provided in this application solves the problem of stations in a local BSS being unable to perform preemption operations due to continuous use of a channel in the local BSS for too long.

[0158] In the PPDU-based preemption mechanism, a set of EDCA contention parameters is provided, and the EDCA contention parameters may be carried in a management frame broadcast by an AP. Specifically, the AP broadcasts a preemption EDCA parameter set element and an EDCA parameter set element, and stations supporting the preemption mechanism use the parameters in the preemption EDCA parameter set element to perform contention and data transmission. Stations not supporting the preemption mechanism use the parameters in the EDCA parameter set element to perform contention and data transmission. It should be understood that the preemption EDCA parameter set element and the EDCA parameter set element are merely examples of names of EDCA contention parameters. The specific names of the elements are not limited in this application.

[0159] In some possible implementations, for UHR stations, stations that do not support the preemption mechanism include stations that do not support the UHR standard and are typically referred to as legacy stations or pre-UHR stations. Stations that do not support the preemption mechanism may further include stations that support the UHR standard but do not support the preemption mechanism. It should be understood that if the next-generation UHR standard uses a PPDU-based preemption mechanism, UHR stations are stations that do not support the preemption mechanism, and next-generation UHR stations can be classified into two types of stations: stations that support preemption and stations that do not support preemption.

[0160] Figure 4 is a diagram of an EDCA parameter set element structure according to one embodiment of the present application. Figure 5 is a diagram of a preemption EDCA parameter set element structure according to one embodiment of the present application.

[0161] A quality of service (QoS) AP can broadcast an EDCA parameter set element 410 and a preemption EDCA parameter set element 510 to indicate the contention parameters used by non-AP STAs in the BSS. Both the EDCA parameter set element 410 and the preemption EDCA parameter set element 510 include one or more or all of the following: element identity document (ID), parameter set element length, QoS information, EDCA update information, AC_BE parameter record, AC_BK parameter record, AC_VI parameter record, and AC_VO parameter record, although the specific parameter values ​​may differ.

[0162] A station identifies the EDCA parameter set element 410 and the preemption EDCA parameter set element 510 through the element ID. For example, a station that does not support the preemption mechanism can receive the contention parameter, identify through the element ID that the contention parameter is an EDCA parameter set element 410, and then perform contention and data transmission through the parameters in the EDCA parameter set element 410. A station that supports the preemption mechanism can receive the contention parameter, identify through the element ID that the contention parameter is a preemption EDCA parameter set element 510, and then perform contention and data transmission through the parameters in the preemption EDCA parameter set element 510.

[0163] The AC_BE parameter record in the EDCA parameter set element 410 and the preemption EDCA parameter set element 510 includes one or more or all of the following: an access category index (ACI), an arbitration interframe space number (AIFSN) field, an exponent form of cwmin (ECWmin), an exponent form of cwmax (ECWmax), and a transmission opportunity (TXOP) limit. It should be understood that in this application, only the AC_BE parameter record is used as an example. The AC_BK parameter record, AC_VI parameter record, and AC_VO parameter record can also include the same fields as the AC_BE parameter record.

[0164] Optionally, the preemption EDCA parameter set element 510 may include ACI / AIFSN and ECWmin / ECWmax fields with the same meanings as those in the EDCA parameter set element 410, or may not include the ACI / AIFSN and ECWmin / ECWmax fields but reuse the same values ​​in the EDCA parameter set element 410.

[0165] The ACI / AIFSN fields indicate the service type. The ECWmin / ECWmax fields are used to determine the minimum and maximum backoff window values, i.e., the minimum contention window (CWmin) and maximum contention window (CWmax), where CWmin=2 ECWmin -1, and CWmax=2 ECWmaxThe transmission opportunity (TXOP) limit field indicates the maximum length of time a station is allowed to continuously use the channel after acquiring it through contention, and is measured in 32 microseconds.

[0166] In the usage process, the AP sets a relatively large TXOP limit value in the preemption EDCA parameter set element 510, i.e., sets the TXOP limit higher than the preset threshold, so that stations supporting preemption can continuously use the channel for a long period of time after successfully acquiring the channel through contention, thereby improving system efficiency. The AP sets a relatively small TXOP limit in the EDCA parameter set element 410, i.e., sets the TXOP limit lower than the preset threshold, to control the maximum length of time that stations not supporting preemption can continuously use the channel, thereby providing more channel access opportunities for stations supporting preemption. It should be understood that in a typical setting method, the TXOP limit in the preemption EDCA parameter set element 510 is equal to or greater than the TXOP limit in the EDCA parameter set element 410.

[0167] Optionally, the preemption EDCA parameter set element 510 may further include a preemption limit field. The preemption limit field indicates the maximum time length of a PPDU, i.e., the time length of a PPDU transmitted by a station supporting preemption is less than the preemption limit, thereby preventing non-low latency services from occupying the channel for long periods of time for use. It should be understood that in a typical configuration method, the preemption limit of the preemption EDCA parameter set element 510 is less than or equal to the TXOP limit of the preemption EDCA parameter set element 510.

[0168] It should be understood that for information exchanges with response frames, the preemption limit should include the total time limit for the information exchange. For example, in the case of a data / block acknowledgement (BA) interaction, the sum of the PPDU carrying the data, the PPDU carrying the BA, and the short interframe space (SIFS) between the two cannot exceed the preemption limit.

[0169] Optionally, the preemption EDCA parameter set element 510 may alternatively be provided with only the preemption limit field and not the TXOP limit field. Alternatively, the preemption EDCA parameter set element 510 may be provided with only the TXOP limit field and not the preemption limit field. The diagram should not be construed as a limitation on the present application.

[0170] It should be understood that the names of the EDCA parameter set element 410 and the preemption EDCA parameter set element 510 and the element names of the EDCA parameter set element 410 and the preemption EDCA parameter set element 510 are merely examples and should not be construed as limitations on the present application.

[0171] It should be understood that one access category (AC) may include multiple services. If one access category includes both low-latency and non-low-latency services, the preemption limit field is applicable to all services. This operation is simple. Optionally, the preemption limit field may alternatively be applicable only to non-low-latency services. If the service being transmitted is a low-latency service, there is no need to provide access opportunities to another low-latency service through the preemption limit field. This operation helps improve system efficiency.

[0172] In the PPDU-based preemption mechanism, through setting the EDCA parameter set element 410 and the preemption EDCA parameter set element 510, a relatively good balance between service delay and system efficiency is achieved.

[0173] FIG. 6 is a schematic flowchart of a communication method according to an embodiment of the present application.

[0174] 610: Receive first information from a second access point.

[0175] The first access point belongs to a first BSS, the first information indicates a first maximum time length for the first station to transmit a PPDU, the second access point and the first station belong to a second BSS, a coverage area of ​​the second BSS overlaps with a coverage area of ​​the first BSS, and the first station supports preemption.

[0176] It should be understood that the coverage area of ​​the second BSS having an overlapping portion with the coverage area of ​​the first BSS indicates that the first BSS and the second BSS are OBSSs of each other, i.e., the OBSS of the first BSS includes the second BSS, and the OBSS of the second BSS includes the first BSS.

[0177] 620: Second information is generated.

[0178] The second information indicates a second maximum time length for which the second station transmits the PPDU, the second maximum time length being less than or equal to the first maximum time length, the second station belonging to the first BSS, and the second station supporting preemption.

[0179] It should be understood that the second information is set by the first access point based on the received first information, and the second maximum time length is equal to or less than the first maximum time length. Since the operation of setting the second information is mutual for APs that are BSSs of each other, all BSSs that support preemption set the second information to the same value, i.e., the minimum value that each AP originally wants to set among the multiple second information.

[0180] 630: Transmit the second information.

[0181] In a possible implementation, the first information may be carried by a field in a beacon frame transmitted by the second access point, and the second information may be carried by a field in a beacon frame transmitted by the first access point.

[0182] It should be understood that the first access point may transmit the second information in a broadcast manner. This diagram should not be construed as a limitation on the present application.

[0183] FIG. 7 is a diagram of another application scenario according to an embodiment of the present application.

[0184] 7, BSS 710 includes AP 701, STA 703, and STA 704. BSS 720 includes AP 702 and STA 705. STA 704, AP 701, and AP 702 are located in the overlapping area of ​​the coverage areas of AP 701 and AP 702. BSS 710 and BSS 720 are each other's OBSS, i.e., the OBSS of BSS 710 includes BSS 720, and the OBSS of BSS 720 includes BSS 710.

[0185] In some possible implementations, BSS 710 in FIG. 7 corresponds to the first BSS described in FIG. 6, BSS 720 corresponds to the second BSS described in FIG. 6, AP 701 corresponds to the first access point described in FIG. 6, AP 702 corresponds to the second access point described in FIG. 6, STA 705 corresponds to the first station described in FIG. 6, and STA 703 and STA 704 correspond to the second stations described in FIG. 6.

[0186] The AP 701 is an AP that supports preemption. For example, the AP 701 can claim in a transmitted beacon frame that the AP 701 supports preemption. For example, a Preemption Support field may be set to a UHR capability element. A Preemption Support field set to 1 indicates that preemption is supported, and a Preemption Support field set to 0 indicates that preemption is not supported, and vice versa. It should be understood that the specific name of the UHR capability element is not limited in this application. If a preemption mechanism is introduced in the next-generation UHR standard, a capabilities element with a different name may be used. The specific name of the Preemption Support field is also not limited in this application.

[0187] The AP 701 can know whether the OBSS AP supports preemption through a beacon frame received from the OBSS AP or through another method, such as through wired transmission. In this embodiment of the present application, the method provided in the present application is described in detail by using an example in which the AP 702 is the OBSS AP of the AP 701. It should be understood that the AP 701 may correspond to multiple OBSS APs. The illustration is only used to facilitate understanding of the method provided in the present application and should not be construed as a limitation on the present application.

[0188] In this embodiment of the present application, a PPDU that allows a preemption operation after the PPDU is completed is called a preemption allowed PPDU, and a PPDU transmitted according to the preemption procedure is called a preemption PPDU. The specific name is not limited in this application, and the name should not be understood as a limitation on this application. In this embodiment of the present application, both an AP and a STA that support preemption can receive or transmit a preemption allowed PPDU.

[0189] In this embodiment of the present application, the station transmitting the preemption grant PPDU is typically a transmission opportunity holder (TXOP holder). However, it should be understood that the station transmitting the preemption grant PPDU can also be applied to a scenario in which the channel grant is transferred or assigned to another station. For example, an AP first becomes a transmission opportunity holder through contention, and then the AP transfers the channel grant to the AP 702 through triggered TXOP sharing, also known as the MU-RTS TXS mechanism or the reverse direction grant (RDG) mechanism. In this case, the AP 702 can also transmit the preemption grant PPDU. For ease of explanation, in this embodiment of the present application, the AP 702 is used as the transmission opportunity holder for illustration.

[0190] Through parameter setting, the AP 701 can set the TXOP limit and / or preemption limit in the BSS of the AP 701 (i.e., BSS 710) to be equal to or less than the parameters corresponding to the BSS 720. Specifically, the following methods are included:

[0191] Method 1: AP 701 sets its TXOP limit to be equal to or less than the TXOP limit of AP 702.

[0192] For example, in this embodiment of the present application, the TXOP limit of AP 701 is referred to as TXOP limit1, and the TXOP limit of AP 702 is referred to as TXOP limit2.

[0193] The AP 701 receives the TXOP limit 2 transmitted by the AP 702, which may be transmitted by using a beacon frame of the AP 702. The AP 701 may set the TXOP limit 1 in the EDCA parameter set element 410 of the AP 701 to be equal to or less than the TXOP limit 2 in the EDCA parameter set element 410 of the AP 702. Alternatively, the AP 701 may set the TXOP limit 1 in the preemption EDCA parameter set element 510 of the AP 701 to be equal to or less than the TXOP limit 2 in the preemption EDCA parameter set element 510 of the AP 702.

[0194] Because the operation of setting the TXOP limit is reciprocal for APs that are each other's OBSS, all BSSs that support preemption set the TXOP limit to the same value, i.e., the minimum value that each AP would originally like to set among multiple TXOP limits. It should be understood that a BSS that supports preemption means that the APs within the BSS support preemption. For example, FIG. 7 is used as an example. BSS 710 and BSS 720 are each other's OBSS, i.e., the OBSS of BSS 710 includes BSS 720, and the OBSS of BSS 720 includes BSS 710. AP 701 receives TXOP Limit 2 sent by AP 702, then sets TXOP Limit 1 to be equal to or less than TXOP Limit 2, and then AP 701 sends TXOP Limit 1. Because AP 701 is the OBSS AP of AP 702, AP 702 receives TXOP Limit 1 sent by AP 701, then sets TXOP Limit 2 to be equal to or less than TXOP Limit 1. This cycle is repeated until BSS 710 and BSS 720 set their TXOP limits to the same value, ie, the minimum value that AP 701 and AP 702 would have originally set among their multiple TXOP limits.

[0195] In this way, after a STA 705 or AP 702 in BSS 720 obtains a TXOP through contention, the channel is released again within a time that does not exceed the TXOP limit. Thus, stations and / or access points in BSS 710 can have more opportunities to transmit low-latency services.

[0196] Method 2: AP 701 sets its preemption limit to be equal to or less than the preemption limit of AP 702.

[0197] For example, in this embodiment of the present application, the preemption limit of AP 701 is referred to as preemption limit 1, and the preemption limit of AP 702 is referred to as preemption limit 2.

[0198] The AP 701 receives the preemption limit 2 transmitted by the AP 702, which may be transmitted by using the beacon frame of the AP 702. The AP 701 may set the preemption limit 1 in the preemption EDCA parameter set element 510 of the AP 701 to be less than or equal to the preemption limit 2 in the preemption EDCA parameter set element 510 of the AP 702.

[0199] Because the operation of setting the preemption limit is reciprocal for APs that are each other's OBSS, all BSSs that support preemption set the preemption limit to the same value, i.e., the minimum value that each AP would originally like to set among multiple preemption limits. For example, FIG. 7 is used as an example. BSS 710 and BSS 720 are each other's OBSS, i.e., the OBSS of BSS 710 includes BSS 720, and the OBSS of BSS 720 includes BSS 710. AP 701 receives Preemption Limit 2 sent by AP 702, then sets Preemption Limit 1 to be equal to or less than Preemption Limit 2, and then AP 701 sends Preemption Limit 1. Because AP 701 is the OBSS AP of AP 702, AP 702 receives Preemption Limit 1 sent by AP 701, then sets Preemption Limit 2 to be equal to or less than Preemption Limit 1. This cycle repeats until BSS 710 and BSS 720 set the preemption limit to the same value, ie, the smallest value that AP 701 and AP 702 would each want to set among the multiple preemption limits.

[0200] In this way, after the STA 705 or AP 702 in the BSS 720 obtains a TXOP through contention, the length of the PPDU transmitted by the STA 705 or AP 702 does not exceed the preemption limit. Therefore, the stations and / or access points in the BSS 710 may have more opportunities to transmit low-latency services.

[0201] It should be understood that before performing preemption to transmit low-latency services, a STA or AP in BSS 710 can first determine that the BSS 720 supports preemption. For example, if the STA or AP in BSS 710 can receive a preemption restriction transmitted by an AP in BSS 720, it can be determined that the AP in BSS 720 supports preemption. Alternatively, the STA or AP in BSS 710 can analyze a beacon frame transmitted by an AP in BSS 720 to determine that the BSS 720 supports the preemption mechanism. Optionally, the AP in BSS 710 can further broadcast a list of all BSSs that support preemption, and the STA in BSS 710 can learn from the broadcast list that the BSS 720 supports preemption.

[0202] It should be understood that after a STA or AP in BSS 720 obtains a TXOP, the STA or AP in BSS 710 sets a basic network allocation vector (basic NAV) based on the received frame transmitted by the STA or AP in BSS 720. According to the rules of the current standard, a station or access point whose basic NAV value is not equal to 0 is not allowed to actively contend for the channel or transmit data. In this case, if a STA or AP in BSS 710 wants to transmit a low-latency service by preemption, the basic NAV set by the STA or AP in BSS 720 must be ignored. That is, even if the basic NAV value of a STA or AP in BSS 710 is greater than 0, the value is considered to be 0, and preemption is initiated.

[0203] Method 3: Both methods 1 and 2 are satisfied.

[0204] AP 701 sets its TXOP limit to be less than or equal to the TXOP limit of AP 702, and AP 701 sets its preemption limit to be less than or equal to the preemption limit of AP 702. In addition, the STAs or APs in BSS 710 ignore the basic NAV set by the STAs or APs in BSS 720 in order to transmit low latency services through preemption.

[0205] According to the communication method provided in this embodiment of the present application, the impact of OBSS on preemption services is taken into consideration, and the TXOP limit parameter or preemption limit parameter is set, so that each station and access point has more opportunities to transmit low-latency services.

[0206] In some possible application scenarios, some APs may only want to implement preemption in a local BSS or some OBSSs associated with the local BSS, and may not want to consider transmitting in all OBSSs that support preemption. Therefore, in this embodiment of the present application, a preemption group may be configured. The preemption group field may be a field in a beacon frame transmitted by the AP, for example, a field in a preemption element, a UHR operation element, or another element. Optionally, the preemption group field may alternatively be placed in a physical layer signal (SIG) field of a PPDU transmitted by the AP.

[0207] Optionally, the preemption group field may include one or more bits. For example, the preemption group field is 1 bit, and the preemption group field is set to 1 to indicate that the BSS in which the AP is located is participating in the preemption group; otherwise, it indicates that the BSS in which the AP is located is not participating in the preemption group. Alternatively, the preemption group field is set to 0 to indicate that the BSS in which the AP is located is participating in the preemption group; otherwise, it indicates that the BSS in which the AP is located is not participating in the preemption group. The AP performs operations only on the BSSs in the preemption group in the three ways shown in FIG. 7.

[0208] For example, the preemption group field is a multi-bit field. A preemption group field set to 0 indicates that the BSS in which the AP is located does not participate in any preemption group, while a preemption group field not set to 0 indicates that the BSS in which the AP is located participates in a specific preemption group. For example, a preemption group field set to "11" indicates that the BSS in which the AP is located participates in the third preemption group. The AP performs operations only on BSSs that participate in the same preemption group as the AP in the three ways shown in Figure 7.

[0209] According to the communication method provided in this embodiment of the present application, the preemption group field is set, so that a BSS that supports preemption can flexibly choose to join or not join a preemption group, thereby controlling the range of access points or stations to perform preemption operations.

[0210] In some possible application scenarios, the AP is expected to independently select an OBSS that is in the same preemption group as the AP. The AP performs the operation only for the OBSSs that are participating in the same preemption group as the AP, in the three ways shown in Figure 7. In this embodiment of the present application, the preemption group member field can be set to indicate the BSSs that are in the same preemption group as the AP.

[0211] In some possible implementations, the preemption group member field may be a preemption BSS color bitmap field. For example, the length of the preemption BSS color bitmap field may be 64 bits. Currently, the BSS color is 6 bits, and there may be up to 64 different BSS colors. Therefore, each bit in the 64 bits of the preemption BSS color bitmap field may correspond to one BSS color.

[0212] It should be understood that the preemption BSS color bitmap is a bitmap that indicates the BSS color values ​​used by members of the preemption group to which the AP belongs. Each bit in the bitmap corresponds to one of 64 BSS colors, with the lowest-numbered bit corresponding to BSS color value 0 and the highest-numbered bit corresponding to BSS color value 63. For example, if a bit in the bitmap is 1, this indicates that at least one BSS that uses the BSS color value corresponding to the bit is in the same preemption group as the AP. If a bit in the bitmap is 0, this indicates that no BSS in the preemption group in which the AP is located uses the BSS color value corresponding to the bit. The BSS color value 0 corresponds to a reserved bit in the bitmap.

[0213] It should be understood that the length of the Preemption BSS Color Bitmap field may be related to the number of OBSSs. If the number of OBSSs is relatively small, a length of less than 64 bits may be used. The length of the Preemption BSS Color Bitmap field is not specified. This example should not be understood as a limitation on the present application.

[0214] In some possible implementations, the preemption group member field may be a Preemption Partial BSSID Bitmap field. A BSS identity document (BSSID) is 6 bytes, i.e., 48 bits. If the bitmap were to indicate all possible BSSID values ​​in a scanning manner, a large amount of space would be wasted. Therefore, in this embodiment of the present application, some bits in the BSSID indicate BSSs that are in the same preemption group as the AP. For example, the Preemption Partial BSSID Bitmap may be selected as 64 bits, each corresponding to a value in BSSID[39:44], or each corresponding to a value in BSSID[38:43]. It should be understood that A[a:b] is the range of A from the ath bit to the bth bit.

[0215] It should be understood that the Preemption Partial BSSID Bitmap field is a bitmap that indicates a portion of the BSSID values ​​of members located in the same preemption group as the AP. For example, each bit in the bitmap corresponds to one of the 64 possible values ​​of BSSID[39:44], with the lowest-numbered bit corresponding to partial BSSID value 0 and the highest-numbered bit corresponding to partial BSSID value 63. For example, if a bit in the bitmap is 1, this indicates that at least one BSS using the partial BSSID value corresponding to the bit is in the same preemption group as the AP. If a bit in the bitmap is 0, this indicates that no BSS in the preemption group in which the AP is located uses the partial BSSID value corresponding to the bit.

[0216] It should be understood that the 64-bit preemption partial BSSID bitmap is merely an example, and this example should not be understood as a limitation on the present application. In a practical application scenario, the preemption partial BSSID bitmap may be selected as a specific length, for example, 32 bits or 16 bits, as needed to accommodate a specific range of BSSIDs.

[0217] In this embodiment of the present application, the AP may indicate the BSSs in the same preemption group as the AP by using either the Preemption BSS Color Bitmap field or the Preemption Partial BSSID Bitmap field. Optionally, the AP may alternatively indicate the BSSs in the same preemption group as the AP by using both the Preemption BSS Color Bitmap field and the Preemption Partial BSSID Bitmap field. This is not a limitation in the present application. The AP performs the operation in the three ways shown in Figure 7 only for the BSSs that participate in the same preemption group as the AP, i.e., for the BSSs that correspond to bits set to 1 in the Preemption BSS Color Bitmap and / or the Preemption Partial BSSID Bitmap.

[0218] According to the communication method provided in this embodiment of the present application, the preemption group member field is set so that the way to establish a preemption group is more flexible.

[0219] The above describes the method provided in the embodiment of the present application. Hereinafter, the apparatus provided in the embodiment of the present application will be described in detail with reference to Figures 8 and 9.

[0220] 8 is a block diagram of a communication device according to an embodiment of the present application. As shown in FIG. 8, the communication device 800 may include a transceiver unit 810 and a processing unit 820.

[0221] It should be understood that the communication device 800 may correspond to a first access point, a second access point, or a second station in the embodiments of the present application. In an exemplary description, the communication device 800 may perform operations, steps, or methods associated with the first access point, the second access point, or the second station in the embodiments of the above-described methods of FIGS. 4 to 7.

[0222] 8 , the present application provides a communication device. The communication device may be disposed in a first access point. The communication device includes: a transceiver unit configured to receive first information from a second access point, the first information indicating a first maximum length of time for a first station to transmit a physical layer protocol data unit (PPDU), the second access point and the first station belonging to a second BSS, a coverage area of ​​the second BSS having an overlapping portion with a coverage area of ​​the first BSS, the first station supporting preemption, and the first access point belonging to the first BSS; a processing unit configured to generate second information, the second information indicating a second maximum length of time for a second station to transmit a PPDU, the second maximum length of time being less than or equal to the first maximum length of time, the second station belonging to the first BSS supporting preemption; and a transceiver unit configured to transmit the second information.

[0223] Optionally, in some embodiments, the processing unit is further configured to determine that a basic network allocation vector of the first access point is set based on a frame transmitted by the second access point or the first station, and the processing unit is further configured to ignore the basic network allocation vector.

[0224] Optionally, in some embodiments, the transceiver unit is further configured to receive third information from the second access point, the third information indicating a third maximum length of time that the first station is allowed to continuously use the channel after acquiring the channel through contention, the processing unit is further configured to generate fourth information, the fourth information indicating a fourth maximum length of time that the second station is allowed to continuously use the channel after acquiring the channel through contention, the fourth maximum length of time being less than or equal to the third maximum length of time, and the transceiver unit is further configured to transmit the fourth information.

[0225] Optionally, in some embodiments, the transceiver unit is further configured to receive fifth information from the second access point, the fifth information indicating a group in which the second BSS is located, and the processing unit is further configured to determine, based on the fifth information, that the second BSS and the first BSS are in the same group.

[0226] Optionally, in some embodiments, the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer signal SIG field of the first PPDU, where the first PPDU is the PPDU transmitted by the second access point.

[0227] Optionally, in some implementations, the transceiver unit is further configured to transmit sixth information, wherein the sixth information indicates a BSS located in the same group as the first BSS.

[0228] Optionally, in some implementations, the sixth information indicates a color or fractional ID of a BSS that is in the same group as the first BSS.

[0229] Optionally, in some implementations, the sixth information is 64 bits in length.

[0230] With reference to the structure of the communication device shown in Figure 8, the present application further provides a communication device. The communication device may be disposed in a first access point. The communications device includes: a transceiver unit configured to receive third information from a second access point, the third information indicating a third maximum length of time that a first station is allowed to continuously use the channel after acquiring the channel through contention, the second access point and the first station belonging to a second BSS, a coverage area of ​​the second BSS having an overlapping portion with a coverage area of ​​the first BSS, the first station supporting preemption, and the first access point belonging to the first BSS; a processing unit configured to generate fourth information, the fourth information indicating a fourth maximum length of time that a second station is allowed to continuously use the channel after acquiring the channel through contention, the fourth maximum length of time being less than or equal to the third maximum length of time, the second station belonging to the first BSS, and the second station supporting preemption; and a transceiver unit configured to transmit the fourth information.

[0231] Optionally, in some embodiments, the transceiver unit is further configured to receive first information from a second access point, the first information indicating a first maximum length of time for the first station to transmit a physical layer protocol data unit (PPDU), the processing unit is further configured to generate second information, the second information indicating a second maximum length of time for the second station to transmit the PPDU, the second maximum length of time being less than or equal to the first maximum length of time, and the transceiver unit is further configured to transmit the second information.

[0232] Optionally, in some embodiments, the processing unit is further configured to determine that a basic network allocation vector of the first access point is set based on a frame transmitted by the second access point or the first station, and the processing unit is further configured to ignore the basic network allocation vector.

[0233] Optionally, in some embodiments, the transceiver unit is further configured to receive fifth information from the second access point, the fifth information indicating a group in which the second BSS is located, and the processing unit is further configured to determine, based on the fifth information, that the second BSS and the first BSS are in the same group.

[0234] Optionally, in some embodiments, the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer signal SIG field of the first PPDU, where the first PPDU is the PPDU transmitted by the second access point.

[0235] Optionally, in some implementations, the transceiver unit is further configured to transmit sixth information, wherein the sixth information indicates a BSS located in the same group as the first BSS.

[0236] Optionally, in some implementations, the sixth information indicates a color or fractional ID of a BSS that is in the same group as the first BSS.

[0237] Optionally, in some implementations, the sixth information is 64 bits in length.

[0238] The present application also provides a communications device, which may be located at a second access point. The communications device includes a transceiver unit configured to transmit first information to the first access point, the first access point belonging to a first BSS, the first information indicating a first maximum time length for a first station to transmit a physical layer protocol data unit (PPDU), the second access point and the first station belonging to the second BSS, a coverage area of ​​the second BSS having an overlapping portion with the coverage area of ​​the first BSS, the first station supporting preemption, and the second access point belonging to the second BSS. The transceiver unit is further configured to receive second information from the first access point, the second information indicating a second maximum time length for a second station to transmit a PPDU, the second maximum time length being less than or equal to the first maximum time length, the second station belonging to the first BSS, and the second station supporting preemption.

[0239] Optionally, in some embodiments, the transceiver unit is further configured to transmit third information to the first access point, the third information indicating a third maximum length of time the first station is allowed to continuously use the channel after acquiring the channel through contention, and the transceiver unit is further configured to receive fourth information from the first access point, the fourth information indicating a fourth maximum length of time the second station is allowed to continuously use the channel after acquiring the channel through contention, the fourth maximum length of time being less than or equal to the third maximum length of time.

[0240] Optionally, in some implementations, the transceiver unit is further configured to transmit fifth information, wherein the fifth information indicates a group in which the second BSS is located.

[0241] Optionally, in some embodiments, the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer SIG field of the first PPDU, where the first PPDU is a PPDU transmitted by the second access point.

[0242] Optionally, in some embodiments, the transceiver unit is further configured to receive sixth information from the first access point, the sixth information indicating a BSS located in the same group as the first BSS.

[0243] Optionally, in some implementations, the sixth information indicates a color or fractional ID of a BSS that is in the same group as the first BSS.

[0244] Optionally, in some implementations, the sixth information is 64 bits in length.

[0245]

[0023] Referring to the structure of the communication device shown in Fig. 8, the present application further provides a communication device. The communication device may be disposed in a second station. The communication device includes: a transceiver unit configured to receive fifth information from a second access point, the fifth information indicating a group in which a second BSS is located, a coverage area of ​​the second BSS having an overlapping portion with a coverage area of ​​the first BSS, the second access point belonging to the second BSS, and the second station belonging to the first BSS; and a processing unit configured to determine, based on the fifth information, that the second BSS and the first BSS are in the same group.

[0246] Optionally, in some embodiments, the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer SIG field of the first PPDU, where the first PPDU is a PPDU transmitted by the second access point.

[0247] Optionally, in some embodiments, the transceiver unit is further configured to receive seventh information, the seventh information indicating whether the second access point supports preemption, and the processing unit is further configured to determine that the second access point supports preemption based on the seventh information.

[0248] Optionally, in some embodiments, the seventh information is carried by a field in a beacon frame transmitted by the first access point or the second access point, and the first access point belongs to the first BSS.

[0249] Optionally, in some embodiments, the processing unit is further configured to determine that a basic network allocation vector of the second station is set based on a frame transmitted by the second access point or the first station, wherein the first station belongs to a second BSS and the first station supports preemption, and the processing unit is further configured to ignore the basic network allocation vector.

[0250] It should be further understood that when the communication device 800 is a chip, the chip includes a transceiver unit and a processing unit. The transceiver unit may be an input / output circuit or a communication interface. The processing unit may be a processor, a microprocessor, or an integrated circuit integrated on the chip.

[0251] The transceiver unit 810 is configured to perform signal reception and transmission operations of the communication device 800 , and the processing unit 820 is configured to perform signal processing operations of the communication device 800 .

[0252] Optionally, the communication device 800 may further include a storage unit 830, which is configured to store instructions.

[0253] 9 is a block diagram of a communication device according to one embodiment of the present application. As shown in the figure, the communication device 900 includes at least one processor 910 and may further include a transceiver 920. Optionally, the communication device 900 further includes a memory 930 configured to store instructions. The processor 910 is coupled to the memory 930 and configured to execute the instructions stored in the memory 930 to control the transceiver 920 to transmit signals and / or receive signals.

[0254] It should be understood that the processor 910 and the memory 930 may be combined into one processing unit, and the processor 910 is configured to execute program code stored in the memory 930 to perform the functions described above. In a specific implementation, the memory 930 may alternatively be integrated into the processor 910 or may be separate from the processor 910.

[0255] It should be further understood that the transceiver 920 may include a receiver (also referred to as a receiver) and a transmitter (also referred to as a transmitter). The transceiver 920 may further include an antenna. There may be one or more antennas. Alternatively, the transceiver 920 may be a communications interface or interface circuit.

[0256] When the communication device 900 is a chip, the chip includes a transceiver unit and a processing unit. The transceiver unit may be an input / output circuit or a communication interface. The processing unit may be a processor, a microprocessor, or an integrated circuit integrated on the chip. An embodiment of the present application further provides a processing device including a processor and an interface. The processor may be configured to perform the method in the above-mentioned method embodiments.

[0257] It is understood that the processing device may be a chip, for example, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on chip (SoC), a central processing unit (CPU), a network processor (NP), a digital signal processor (DSP), a microcontroller unit (MCU), a programmable logic device (PLD), or another integrated chip.

[0258] In one implementation process, the steps in the above-mentioned method can be implemented by using hardware integrated logic circuits in a processor or by using instructions in the form of software. The steps of the method disclosed with reference to the embodiments of the present application can be directly executed by a hardware processor, or can be executed by using a combination of hardware and software modules in a processor. The software modules can be located in a mature storage medium in the art, such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically erasable programmable memory, or a register. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps in the above-mentioned method in combination with the hardware of the processor. To avoid repetition, details will not be described again here.

[0259] An embodiment of the present application further provides a computer-readable storage medium, which stores computer instructions for implementing the method performed by the first access point in the aforementioned method embodiment.

[0260] For example, when the computer program is executed by a computer, the computer can perform the method performed by the first access point in the method embodiments described above.

[0261] An embodiment of the present application further provides a computer-readable storage medium, which stores computer instructions for implementing a method performed by a second access point in the aforementioned method embodiment.

[0262] For example, when the computer program is executed by a computer, the computer can perform the method performed by the second access point in the method embodiments described above.

[0263] An embodiment of the present application further provides a computer-readable storage medium, which stores computer instructions for implementing the method performed by the second station in the aforementioned method embodiment.

[0264] For example, when the computer program is executed by a computer, the computer can perform the method performed by the second station in the method embodiments described above.

[0265] An embodiment of the present application further provides a computer program product including instructions, which, when executed by a computer, enable the computer to perform a method performed by a first access point, a second access point, or a second station in the aforementioned method embodiments.

[0266] An embodiment of the present application further provides a communication system, the communication system including a first access point, a second access point, and / or a second station, wherein the first access point is configured to perform the method steps performed by the first access point in the aforementioned method embodiment, the second access point is configured to perform the method steps performed by the second access point in the aforementioned method embodiment, and the second station is configured to perform the method steps performed by the second station in the aforementioned method embodiment.

[0267] For convenience and simplicity, it will be clearly understood by those skilled in the art that for the description of the contents and beneficial effects related to any one of the communication devices provided above, reference should be made to the corresponding method embodiments provided above, and details will not be repeated here.

[0268] The specific structure of the implementation of the method provided in the embodiment of the present application is not particularly limited in the embodiment of the present application, as long as a program recording the code of the method provided in the embodiment of the present application can be executed to perform communication according to the method provided in the embodiment of the present application. For example, the method provided in this embodiment of the present application may be executed by the first access point, the second access point, or the second station, or may be executed by a functional module located in the first access point, the second access point, or the second station and capable of calling and executing the program.

[0269] Various aspects or features of the present application may be implemented as a method, apparatus, or article of manufacture using standard programming and / or engineering techniques. The term "artifact" as used herein may encompass a computer program accessible from any computer-readable device, carrier, or media.

[0270] The computer-readable storage medium may be any available medium that can be accessed by a computer, or may be a data storage device that integrates one or more available media, such as a server or a data center. The available medium (or computer-readable medium) may include various media that can store program code, such as, but not limited to, magnetic media or magnetic storage devices (e.g., floppy disks, hard disks (e.g., removable hard disks), or magnetic tapes), optical media (e.g., optical disks, compact discs (CDs), or digital versatile discs (DVDs)), smart cards, and flash memory devices (e.g., erasable programmable read-only memory (EPROM), cards, sticks, or key drives), or semiconductor media (e.g., solid-state disks (SSDs), USB flash drives, read-only memory (ROM), or random access memory (RAM)).

[0271] 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 transporting instructions and / or data.

[0272] It should be understood that the memory referred to in the embodiments of the present application may be volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. Nonvolatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory may be random access memory (RAM). For example, RAM may be used as an external cache. By way of example and not limitation, RAM may include multiple forms such as static random access memory (static RAM, SRAM), dynamic random access memory (dynamic RAM, DRAM), synchronous dynamic random access memory (synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (double data rate SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchlink dynamic random access memory (synchlink DRAM, SLDRAM), and direct rambus random access memory (direct rambus RAM, DR RAM).

[0273] It should be noted that the memory (storage module) may be integrated into the processor when the processor is a general-purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component.

[0274] It should further be noted that memory, as described herein, is intended to include, without being limited to, these and any other suitable types of memory.

[0275] In some embodiments provided in the present application, it should be understood that the disclosed devices and methods may be implemented in other ways. For example, the device embodiments described above are merely examples. For example, the division into units described above is merely a logical division of functions, and actual implementations may employ 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 implemented. In addition, the shown or described mutual couplings or direct couplings or communication connections may be implemented through some interfaces. Indirect couplings or communication connections between devices or units may be implemented in electronic, mechanical, or other forms.

[0276] The aforementioned units described as separate parts may or may not be physically separate, and parts presented as units may or may not be physical units, and may be located in one location or distributed across multiple network units. Some or all of the units may be selected based on actual requirements to implement the solutions provided in this application.

[0277] In addition, the functional units in the embodiments of the present application may be integrated into one unit, each of the units may exist physically alone, or two or more units may be integrated into one unit.

[0278] All or part of the above embodiments may be implemented using software, hardware, firmware, or any combination thereof.

[0279] When software is used to implement the embodiments, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the procedures or functions according to the embodiments of the present application are generated, in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. For example, the computer may be a personal computer, a server, or a network device. The computer instructions may be stored in a computer-readable storage medium or transmitted from a computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center to another website, computer, server, or data center via a wired (e.g., coaxial cable, optical fiber, or digital subscriber line) or wireless (e.g., infrared, radio, or microwave) method. See the above description of computer-readable storage media.

[0280] It should be understood that in the embodiments of the present application, numbers such as "first" and "second" are used merely to distinguish different objects, for example, to distinguish different network devices, and do not limit the scope of the embodiments of the present application, and the embodiments of the present application are not limited thereto.

[0281] It should be further understood that in this application, both "when" and "if" mean that the network element performs the corresponding processing in the intended situation, but do not limit the time, require the network element to have the action determined on the fly, or imply any other limitation.

[0282] It should be further understood that in the embodiments of the present application, "B corresponding to A" means that B is associated with A and B can be determined based on A. However, it should be further understood that determining B based on A does not mean that B is determined based only on A. B can instead be determined based on A and / or other information.

[0283] The above description is merely a specific embodiment of the present application and is not intended to limit the scope of protection of the present application. Any variations or replacements that can be easily conceived by those skilled in the art within the technical scope disclosed in the present application shall fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be subject to the scope of protection of the claims. [Explanation of symbols]

[0284] 310 processor 320 Transmitter 330 memory 340 receiver 350 Signal Detector 360 Digital Signal Processor 370 User Interface 410 EDCA Parameter Set Elements 510 Preemption EDCA Parameter Set Elements 720 Transceiver 800 Communication Equipment 810 Transceiver Unit 820 Processing Unit 830 Storage Unit 900 Communication Devices 910 processor 920 Transceiver 930 memory

Claims

1. 1. A communication method performed by a first access point or a communication device located at the first access point, the first access point belonging to a first basic service set (BSS), the method comprising: receiving first information from a second access point, the first information indicating a first maximum time length for a first station to transmit a physical layer protocol data unit (PPDU), the second access point and the first station belonging to a second BSS, a coverage area of ​​the second BSS having an overlapping portion with a coverage area of ​​the first BSS, and the first station supporting preemption; generating second information, the second information indicating a second maximum time length for a second station to transmit a PPDU, the second maximum time length being less than or equal to the first maximum time length, the second station belonging to the first BSS, and the second station supporting preemption; transmitting the second information; A method comprising:

2. The method comprises: determining that a basic network allocation vector of the first access point is set based on a frame transmitted by the second access point or the first station; ignoring the basic network allocation vector; 10. The method of claim 1, further comprising:

3. The method comprises: receiving third information from the second access point, the third information indicating a third maximum length of time the first station is allowed to continuously use the channel after acquiring the channel through contention; generating fourth information, the fourth information indicating a fourth maximum length of time that the second station is allowed to continuously use the channel after acquiring the channel through contention, the fourth maximum length of time being less than or equal to the third maximum length of time; transmitting the fourth information; 3. The method of claim 1 or 2, further comprising:

4. The method comprises: receiving fifth information from the second access point, the fifth information indicating a group in which the second BSS is located; determining, based on the fifth information, that the second BSS and the first BSS are in the same group; 4. The method of claim 1, further comprising:

5. 5. The method of claim 4, wherein the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer signal SIG field of a first PPDU, and the first PPDU is the PPDU transmitted by the second access point.

6. The method comprises: transmitting sixth information, the sixth information indicating a BSS located in the same group as the first BSS; 4. The method of claim 1, further comprising:

7. The method of claim 6 , wherein the sixth information indicates a color or partial identification ID of the BSS that is in the same group as the first BSS.

8. 8. The method according to claim 6, wherein the sixth information has a length of 64 bits.

9. 1. A communication method performed by a first access point or a communication device located at the first access point, the first access point belonging to a first basic service set (BSS), the method comprising: receiving third information from the second access point, the third information indicating a third maximum length of time that a first station is allowed to continuously use the channel after acquiring the channel through contention, the second access point and the first station belonging to a second BSS, a coverage area of ​​the second BSS having an overlapping portion with a coverage area of ​​the first BSS, and the first station supporting preemption; generating fourth information, the fourth information indicating a fourth maximum length of time a second station is allowed to continuously use the channel after acquiring the channel through contention, the fourth maximum length of time being less than or equal to the third maximum length of time, the second station belonging to the first BSS, and the second station supporting preemption; transmitting the fourth information; A method comprising:

10. A communication method performed by a second access point or a communication device located at the second access point, the second access point belonging to a second BSS, the method comprising: transmitting first information to a first access point, the first access point belonging to a first BSS, the first information indicating a first maximum time length for a first station to transmit a physical layer protocol data unit (PPDU), the second access point and the first station belonging to the second BSS, a coverage area of ​​the second BSS having an overlapping portion with a coverage area of ​​the first BSS, and the first station supporting preemption; receiving second information from the first access point, the second information indicating a second maximum time length for a second station to transmit a PPDU, the second maximum time length being less than or equal to the first maximum time length, the second station belonging to the first BSS, and the second station supporting preemption; A method comprising:

11. The method comprises: transmitting third information to the first access point, the third information indicating a third maximum length of time the first station is allowed to continuously use the channel after acquiring the channel through contention; receiving fourth information from the first access point, the fourth information indicating a fourth maximum length of time that the second station is allowed to continuously use the channel after acquiring the channel through contention, the fourth maximum length of time being less than or equal to the third maximum length of time; 11. The method of claim 10, further comprising:

12. The method comprises: transmitting fifth information, the fifth information indicating a group in which the second BSS is located; 12. The method of claim 10 or 11, further comprising:

13. 13. The method of claim 12, wherein the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer SIG field of a first PPDU, and the first PPDU is the PPDU transmitted by the second access point.

14. The method comprises: receiving sixth information from the first access point, the sixth information indicating a BSS located in the same group as the first BSS; 12. The method of claim 10 or 11, further comprising:

15. The method of claim 14 , wherein the sixth information indicates a color or a fractional ID of the BSS that is in the same group as the first BSS.

16. 16. The method according to claim 14, wherein the sixth information has a length of 64 bits.

17. 1. A communication method performed by a second station or a communication device located at the second station, the second station belonging to a first BSS, the method comprising: receiving fifth information from a second access point, the fifth information indicating a group in which a second BSS is located, a coverage area of ​​the second BSS having an overlapping portion with a coverage area of ​​the first BSS, and the second access point belonging to the second BSS; determining, based on the fifth information, that the second BSS and the first BSS are in the same group; A method comprising:

18. 18. The method of claim 17, wherein the fifth information is carried by a field in a beacon frame transmitted by the second access point or a physical layer SIG field of a first PPDU, and the first PPDU is the PPDU transmitted by the second access point.

19. The method comprises: receiving seventh information, the seventh information indicating whether the second access point supports preemption; determining, based on the seventh information, that the second access point supports preemption; 19. The method of claim 17 or 18, further comprising:

20. 20. The method of claim 19, wherein the seventh information is carried by a field in a beacon frame transmitted by a first access point or the second access point, and the first access point belongs to the first BSS.

21. The method comprises: determining that a basic network allocation vector of the second station is set based on a frame transmitted by the second access point or a first station, the first station belonging to the second BSS, and the first station supporting preemption; ignoring the basic network allocation vector; 21. The method of any one of claims 17 to 20, further comprising:

22. 10. A communications device comprising: a processor; the processor coupled to a memory; the memory storing instructions that, when executed by the processor, enable the processor to perform the method of any one of claims 1 to 9.

23. 17. A communications device comprising: a processor; the processor coupled to a memory; the memory storing instructions that, when executed by the processor, enable the processor to perform the method of any one of claims 10 to 16.

24. 22. A communications device comprising: a processor; the processor coupled to a memory; the memory storing instructions that, when executed by the processor, enable the processor to perform the method of any one of claims 17 to 21.

25. 22. A communication system comprising a first access point, a second access point, and / or a second station, wherein the first access point is configured to perform the method of any one of claims 1 to 9, the second access point is configured to perform the method of any one of claims 10 to 16, and the second station is configured to perform the method of any one of claims 17 to 21.

26. 22. A computer readable storage medium storing a computer program or instructions, said computer program or instructions being used to implement the method of any one of claims 1 to 21.

27. 22. A chip comprising a processor and an interface configured to call from said memory a computer program stored in said memory and to execute said computer program, in order to perform the method of any one of claims 1 to 21.

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