Multi-access point (AP) coordinated transmission method and related device

Abstract

The embodiment of the invention discloses a multi-access point (AP) coordination method and a related device. The method provided by the embodiment of the invention comprises the following steps: a first access point (AP) generates a first wireless frame, and the first wireless frame comprises indication information used for indicating the transmission duration of a second wireless frame sent by a second access point (AP); the first access point AP sends the first wireless frame to the second access point AP; and the first access point AP sends a third wireless frame to a first station STA associated with the first access point AP during the sending period of the second wireless frame.

Description

[0001] This application is a divisional application. The application number of the original application is 201810133190.2, and the original application date is February 8, 2018. The entire content of the original application is incorporated into this application by reference. Technical Field

[0002] The present application relates to the field of communications, and in particular to a method for coordinating transmission of multiple access points (APs) and related devices. Background Art

[0003] With the development of wireless networks and the increasing popularity of wireless local area network (WLAN) technology, WLAN devices are becoming more and more dense. Since wireless access points (APs) are easy to deploy, the increasing density of APs also brings more interference between cells. How to reduce interference between cells and improve user service quality through collaboration between APs has also become an issue that needs to be considered in the next generation of WiFi technology.

[0004] In the prior art, coordinated beamforming (co-BF) technology can be used to reduce inter-cell interference. The co-BF technology can keep the correlation between effective channels low, for example, Figure 1a As shown, it is a schematic diagram of an exemplary co-BF technology in the prior art, in which AP1 is associated with station (STA) 1, and AP2 is associated with STA2. Before AP1 and STA1, and AP2 and STA2 transmit data, AP1 needs to obtain the channel state information (CSI) of the downlink channel between AP1 and STA1, and then perform joint beamforming according to the CSI, so that the beam is directed to STA1 while avoiding the direction of STA2, thereby avoiding interference with STA2. In addition, the same is true for AP2. Therefore, in the scenario of using co-BF, not only can the concurrent transmission of the two APs be achieved, but also the interference between the two transmissions can be avoided, and the overall throughput of the network can be effectively improved.

[0005] However, the CSI acquisition process is relatively complicated and will occupy certain channel resources. When the number of users is large and the channel changes rapidly, CSI feedback is a considerable expense. Summary of the invention

[0006] The embodiments of the present application provide a multi-access point AP coordinated transmission method and related devices, which are used to solve the problem of occupying more channel resources when obtaining CSI in the prior art.

[0007] The first aspect of an embodiment of the present application provides a method for coordinated transmission of multiple access points AP, including: a first access point AP generates a first radio frame, wherein the first radio frame contains indication information, and the indication information is used to indicate the transmission duration of a second radio frame sent by a second access point AP. After the first access point AP generates the first radio frame, it sends the first radio frame to the second access point AP; and during the transmission period of the second radio frame, the first access point AP sends a third radio frame to a first station STA associated with the first access point AP. In an embodiment of the present application, the first access point AP sends a first radio frame to the second access point AP, so that at least one second access point AP can simultaneously send a second radio frame with the same transmission duration to the second station STA according to the first radio frame, and synchronization of multiple access points AP is achieved by sending control information, which solves the problem of occupying more channel resources when obtaining CSI in the prior art.

[0008] In a possible implementation, the indication information includes the sending time and the end time of the second radio frame. In this implementation, the first access point AP indicates the sending time and the end time of the second radio frame to the second access point AP, so that the second access point AP can determine the transmission duration of the second radio frame through the indication.

[0009] In a possible implementation, the third radio frame is sent at the same time as the second radio frame. In this implementation, the third radio frame is sent at the same time as the second radio frame, which reduces interference between the first access point AP and the second access point AP.

[0010] In a possible implementation, the transmission time of the third radio frame is before the transmission time of the second radio frame. In this implementation, the transmission time of the third radio frame can also be earlier than the transmission time of the second radio frame. Then, after the transmission of the radio frame with a later end time in the second and third radio frames is completed, the first station STA can then send a confirmation frame in response to the third radio frame, and the second station STA can then send a confirmation frame in response to the second radio frame. This avoids the situation where one access point AP is sending while another access point AP is receiving, and reduces the interference value between the first AP and the second AP.

[0011] In a possible implementation, the indication information includes identification information of the second access point AP. In this implementation, the first wireless frame may also include identification information of the second access point AP, so that multiple second APs can determine whether to participate in coordinated transmission with the first access point AP according to the identification information.

[0012] In a possible implementation, the first wireless frame also carries one or more of the following: the transmission power information of the second access point AP; the maximum interference threshold information that the first access point AP can tolerate; the identification information of the first site STA; the transmission power information of the first site STA; the transmission power information of the first access point AP. In this implementation, the first wireless frame can also carry other multiple indication information, adding the function of multi-AP joint resource management. By coordinating the transmission power of the second access point AP and the transmission power information of the first access point, the interference of the first access point AP to the second site STA and the interference of the second access point AP to the first site STA can be effectively controlled. By indicating the maximum interference threshold information that the first access point AP can tolerate to the second access point AP, the second access point AP controls the transmission power of the second site STA to avoid the interference value of the second site STA to the first access point AP exceeding the maximum interference threshold information that the first access point AP can tolerate. By indicating the identification information of the first site STA and the transmission power information of the first site STA to the second access point AP, the second access point AP can predict the interference value of the first site STA to the second access point AP, thereby effectively controlling the interference of the first site STA to the second access point AP.

[0013] In a possible implementation, the transmission duration of the third radio frame is the same as the transmission duration of the second radio frame. In this implementation, the first access point AP configures the transmission duration of the second radio frame to be the same as the transmission duration of the third radio frame, so that the end time of the second radio frame can be aligned with the end time of the third radio frame, thereby reducing interference between the first access point AP and the second access point AP.

[0014] In a possible implementation, before the first access point AP sends the first radio frame to the second access point AP, the process further includes: the first access point AP determines the second access point AP; the first access point AP allocates resource scheduling information to the second access point AP, the resource scheduling information is used to indicate the channel resources used by the second access point AP to send the second radio frame. In this implementation, the first access point AP allocates the channel resources used by the second access point AP to send the second radio frame to the second access point AP, thereby increasing the efficiency of the second access point AP in sending the second radio frame.

[0015] In a possible implementation, before the first access point AP sends the first wireless frame to the second access point AP, the method further includes: the first access point AP successfully competes for a channel to transmit the first wireless frame; or the first access point AP receives a request frame sent by an access point AP that successfully competes for a channel, the request frame being used to request the first access point AP to use the channel to transmit the first wireless frame. In this implementation, the first access point AP can compete for a channel by itself to transmit the first wireless frame, or it can use a channel competed for by other APs to transmit the first wireless frame, thereby increasing the flexibility of the first access point AP in transmitting the first wireless frame.

[0016] The second aspect of the embodiment of the present application provides a method for coordinated transmission of multiple access point APs, including: a second access point AP receives a first wireless frame sent by a first access point AP, wherein the first wireless frame includes indication information for indicating the transmission duration of a second wireless frame; after receiving the first wireless frame, during the period in which the first access point AP sends a third wireless frame to a first station STA associated with the first access point AP, the second access point AP sends a second wireless frame to a second station STA associated with the second access point AP. In the embodiment of the present application, the second access point AP receives the first wireless frame sent by the first access point AP, so that at least one second access point AP can simultaneously send a second wireless frame with the same transmission duration to a second station STA according to the first wireless frame, and synchronization of multiple access point APs is achieved by sending control information, solving the problem of occupying more channel resources when obtaining CSI in the prior art.

[0017] In one possible implementation, the indication information includes the sending time and the end time of the second wireless frame. In this implementation, the first access point AP indicates the sending time and the end time of the second wireless frame to the second access point AP through the first wireless frame, so that the second access point AP can determine the transmission duration of the second wireless frame through the indication.

[0018] In a possible implementation, the transmission time of the second radio frame is the same as the transmission time of the third radio frame, wherein the third radio frame is sent by the first access point AP to the first station STA associated with the first access point AP during the transmission of the second radio frame, and the transmission duration of the third radio frame is the same as the transmission duration of the second radio frame. In this implementation, it is explained that the transmission time of the third radio frame is the same as the second radio frame, which reduces the interference between the first access point AP and the second access point AP.

[0019] In a possible implementation, the transmission time of the second radio frame is before the transmission time of the third radio frame. In this implementation, the transmission time of the second radio frame can also be earlier than the transmission time of the third radio frame. Then, after the transmission of the radio frame with a later end time in the second and third radio frames is completed, the first station STA can then send a confirmation frame in response to the third radio frame, and the second station STA can then send a confirmation frame in response to the second radio frame. This avoids the situation where one access point AP is sending while another access point AP is receiving, and reduces the interference value between the first AP and the second AP.

[0020] In a possible implementation, the indication information includes identification information of the second access point AP. In this implementation, the first wireless frame may also include identification information of the second access point AP, so that multiple second APs can determine whether to participate in coordinated transmission with the first access point AP according to the identification information.

[0021] In a possible implementation, the first wireless frame also carries one or more of the following: the transmission power information of the second access point AP; the maximum interference threshold information that the first access point AP can tolerate; the identification information of the first site STA; the transmission power information of the first site STA; the transmission power information of the first access point AP. In this implementation, the first wireless frame can also carry other multiple indication information, adding the function of multi-AP joint resource management. By coordinating the transmission power of the second access point AP and the transmission power information of the first access point, the interference of the first access point AP to the second site STA and the interference of the second access point AP to the first site STA can be effectively controlled. By indicating the maximum interference threshold information that the first access point AP can tolerate to the second access point AP, the second access point AP controls the transmission power of the second site STA to avoid the interference value of the second site STA to the first access point AP exceeding the maximum interference threshold information that the first access point AP can tolerate. By indicating the identification information of the first site STA and the transmission power information of the first site STA to the second access point AP, the second access point AP can predict the interference value of the first site STA to the second access point AP, thereby effectively controlling the interference of the first site STA to the second access point AP.

[0022] In a possible implementation, the transmission duration of the second radio frame is the same as the transmission duration of the third radio frame. In this implementation, the first access point AP configures the transmission duration of the second radio frame to be the same as the transmission duration of the third radio frame, so that the end time of the second radio frame can be aligned with the end time of the third radio frame, thereby reducing interference between the first access point AP and the second access point AP.

[0023] In a possible implementation, before the second access point AP receives the first wireless frame sent by the first access point AP, the second access point AP also includes: when the second access point AP successfully competes for a channel, the second access point AP sends a request frame to the first access point AP, and the request frame is used to request the first access point AP to use the channel to send the first wireless frame. In this implementation, a method for the first access point AP to access the channel is provided, so that the first access point AP can transmit the first wireless frame according to the channel competed for by the second access point AP.

[0024] In one possible implementation, the indication information also includes resource scheduling information, and the resource scheduling information is used to indicate the channel resources used by the second access point AP to send the second wireless frame. In this implementation, the first access point AP allocates the channel resources used to send the second wireless frame to the second access point AP, thereby increasing the efficiency of the second access point AP in sending the second wireless frame.

[0025] The third aspect of the embodiment of the present application provides a method for coordinated transmission of multiple access points AP, including: a first access point AP generates a first radio frame. After generating the first radio frame, the first access point AP sends the first radio frame to the second access point AP, wherein the first radio frame is used to trigger the second access point AP to send a second radio frame to a second station STA associated with the second access point AP, wherein the first radio frame includes a first indication information, so that the second access point AP determines the transmission end time of the second radio frame according to the first indication information. In the embodiment of the present application, the first access point AP sends the first radio frame to the second access point AP, triggering the second access point AP to send the second radio frame to the second station STA, and the second access point AP can determine the transmission end time of the second radio frame according to the first indication information in the first radio frame, so that multiple second access points AP can end transmission at the same time, that is, there will be no situation where one AP is sending and another AP is receiving, which reduces interference between APs and between STAs.

[0026] The fourth aspect of the embodiment of the present application provides a method for coordinated transmission of multiple access points AP, including: a second access point AP receives a first wireless frame sent by a first access point AP, the first wireless frame carrying first indication information; the second access point AP determines the transmission end time of the second wireless frame according to the first indication information; the second access point AP sends the second wireless frame to the second station STA associated with the second access point AP. In the embodiment of the present application, the second access point AP receives the first wireless frame sent by the first access point AP, and determines the transmission end time of the second wireless frame according to the first indication information in the first wireless frame, so that multiple second access points AP can end transmission at the same time, that is, there will be no situation where one AP is sending and another AP is receiving, which reduces interference between APs and between STAs.

[0027] In a possible implementation, the first indication information is used to indicate the transmission end time of the first radio frame or the transmission duration of the first radio frame, and the transmission end time of the first radio frame is the same as the transmission end time of the second radio frame. The second access point AP determines the transmission end time of the second radio frame according to the first indication information, including: the second access point AP determines the transmission end time of the first radio frame as the transmission end time of the second radio frame; or, the second access point AP determines the transmission end time of the first radio frame according to the transmission duration of the first radio frame and the transmission start time of the first radio frame, and the transmission end time of the first radio frame is equal to the transmission end time of the second radio frame. In this implementation, the transmission end time of the second radio frame sent by the second access point AP is the same as the transmission end time of the first radio frame sent by the first access point AP, so there will be no situation where one access point is sending and the other access point is receiving, and correspondingly, there will be no situation where one station is receiving data and the other station is sending a confirmation frame, which can avoid interference between access points and interference between stations.

[0028] The fifth aspect of the embodiment of the present application provides a channel information prediction method, including: a first site STA receives a broadcast frame from a first access point AP, wherein the broadcast frame includes identification information of a second access point AP, and the broadcast frame is used to trigger the first site STA to detect the channel between the second access point AP and the first site STA. Among them, the first site STA is associated with the first access point AP. The first site STA determines the channel quality information of the target channel based on the wireless frame sent by the received target AP, the target channel is the channel between the target AP and the first site STA, and the target AP is included in the second access point AP; the first site STA sends a feedback frame to the first access point AP, and the feedback frame includes the channel quality information of the target channel. In the embodiment of the present application, the channel quality information of the target channel fed back by the first site STA enables the first access point AP to select a suitable MCS when scheduling the first site STA for transmission, so as to achieve a balance between the transmission rate and the packet loss rate.

[0029] In a possible implementation, the broadcast frame may also include sequence indication information, wherein the sequence indication information is used to instruct the second access point AP to sequentially broadcast zero data packets NDP. In this implementation, the first access point AP may instruct the second access point AP to sequentially send NDPs, so that the first station STA measures channel information according to the NDPs sequentially sent by multiple second access points APs. This is more orderly and efficient than the first station STA measuring channel information by receiving beacon frames sent by multiple second access points APs at different intervals.

[0030] In a possible implementation, the wireless frame sent by the target AP may be an NDP, and after the first station STA receives the wireless frame sent by the target AP and before the first station STA sends a feedback frame to the first access point AP, it also includes: the first station STA determines which AP is the target AP according to the sequence indication information. In this implementation, after the first station STA receives the wireless frame, it needs to determine which AP sent the wireless frame according to the sequence indication information, so that when the first station STA gives feedback to the first access point AP, the first access point AP can be informed of which access point the channel between the first station STA and the first station AP is detected.

[0031] In a possible implementation, before the first station STA sends a feedback frame to the first access point AP, it also includes: the first station STA receives a trigger frame sent by the first access point AP, wherein the trigger frame is used to trigger the first station STA to send the feedback frame, and the trigger frame contains resource scheduling information, and the resource scheduling information is used to indicate the channel resources used by the first station STA to send the feedback frame; or, the first station STA successfully competes for a channel, and the channel is used to send the feedback frame. In this implementation, two methods for the first station STA to send a feedback frame are provided, including using the channel resources allocated by the first access point AP to send the feedback frame, or sending the feedback frame through the channel obtained through competition, wherein the feedback frame is sent using the channel resources allocated by the first access point AP, so that the first STA does not need to compete for the channel, thereby increasing the efficiency of the first station STA sending the feedback frame.

[0032] The sixth aspect of the embodiment of the present application provides a channel information prediction method, including: a first access point AP sends a broadcast frame to a first station STA associated with the first access point AP, the broadcast frame carries identification information of a second access point AP, and the broadcast frame is used to trigger the first station STA to detect the channel between the second access point AP and the first station STA. The first access point AP then receives a feedback frame sent by the first station STA, the feedback frame carries channel quality information of a target channel detected by the first station STA, wherein the target channel is a channel between the target AP and the first station STA, the target AP is an AP communicating with the first station STA, and the target AP is included in the second access point AP. In the embodiment of the present application, the first access point AP triggers the first station STA to detect the channel between the second access point AP and the first station STA through a broadcast frame, and receives the channel quality information of the target channel that can be detected by the second access point AP fed back by the first station STA, so that the first access point AP can predict the signal-to-interference ratio of the first station STA according to the channel quality information of the target channel, and then when scheduling the first station STA for transmission, the first access point AP can select a suitable MCS to achieve a balance between the transmission rate and the packet loss rate.

[0033] In a possible implementation, after the first access point AP receives the feedback frame sent by the first station STA, the method further includes: the first access point AP determines the signal-to-interference ratio SIR of the first station STA according to the channel quality information of the target AP. In this implementation, the first access point AP determines the SIR of the first station STA and can select a suitable MCS when scheduling the first station STA for transmission to achieve a balance between transmission data and packet loss rate.

[0034] In a possible implementation, before the first access point AP receives the feedback frame sent by the first station STA, it also includes: the first access point AP sends a trigger frame to the first station STA, the trigger frame is used to trigger the first station STA to send the feedback frame, the trigger frame carries resource scheduling information, and the resource scheduling information is used to indicate the channel resources used by the first station STA to send the feedback frame. In this implementation, a method for the first station STA to send a feedback frame is provided, including using the channel resources allocated by the first access point AP to send the feedback frame, thereby improving the efficiency of the first station STA in sending the feedback frame.

[0035] In a possible implementation, the broadcast frame also carries sequence indication information, and the sequence indication information is used to indicate the sequence in which the second access point AP sends the empty data packet NDP, so that the first station STA performs signal quality detection on the channel between the second access point AP and the first station STA according to the received NDP. In this implementation, the first access point AP can instruct the second access point AP to send NDPs sequentially, so that the first station STA measures the channel information according to the NDPs sequentially sent by multiple second access point APs. Compared with the first station STA measuring the channel information by receiving beacon frames sent by multiple second access point APs at different intervals, it is more orderly and efficient.

[0036] The seventh aspect of the embodiment of the present application provides a device for coordinated transmission of multiple access points AP, which is applied to the first access point AP side, including: a processor, which is used to generate a first wireless frame, wherein the first wireless frame contains indication information for indicating the transmission duration of a second wireless frame sent by a second access point AP; a transceiver, which is used to send the first wireless frame to the second access point AP; and, the transceiver is also used to send a third wireless frame to a first station STA associated with the first access point AP during the transmission of the second wireless frame. In the embodiment of the present application, the transceiver sends the first wireless frame to the second access point AP, so that at least one second access point AP can simultaneously send a second wireless frame with the same transmission duration to the second station STA according to the first wireless frame, and the synchronization of multiple access points AP is achieved by sending control information, which solves the problem of occupying more channel resources when obtaining CSI in the prior art.

[0037] The eighth aspect of the embodiment of the present application provides a device for coordinated transmission of multiple access points AP, which is applied to the second access point AP side, including: a transceiver, which is used to receive a first wireless frame sent by the first access point AP, wherein the first wireless frame contains indication information of the transmission duration of the second wireless frame; during the period when the first access point AP sends a third wireless frame to the first station STA associated with the first access point, the transceiver is also used to send the second wireless frame to the second station STA associated with the second access point AP. In the embodiment of the present application, the transceiver receives the first wireless frame sent by the first access point AP, and simultaneously sends a second wireless frame with the same transmission duration to the second station STA based on the first wireless frame, and realizes the synchronization of multiple access points AP by sending control information, which solves the problem of occupying more channel resources when obtaining CSI in the prior art.

[0038] The ninth aspect of the embodiment of the present application provides a device for coordinated transmission of multiple access points AP, which is applied to the first access point AP side, including: a processor, which is used to generate a first radio frame; a transceiver, which is used to send a first radio frame to a second access point AP, and the first radio frame is used to trigger the second access point AP to send a second radio frame to a second station STA associated with the second access point AP; wherein the first radio frame includes first indication information, and the first indication information is used to enable the second access point AP to determine the transmission end time of the second radio frame. In the embodiment of the present application, the transceiver sends a first radio frame to the second access point AP, triggering the second access point AP to send a second radio frame to the second station STA, so that the second access point AP can determine the transmission end time of the second radio frame according to the first indication information in the first radio frame, and multiple second access points AP can end transmission at the same time, that is, there will be no situation where one AP is sending and another AP is receiving, which reduces interference between APs and between STAs.

[0039] The tenth aspect of the embodiment of the present application provides a device for coordinated transmission of multiple access points AP, which is applied to the second access point AP side, and includes: a transceiver, which is used to receive a first wireless frame sent by the first access point AP, and the first wireless frame carries first indication information; a determination unit, which is used to determine the transmission end time of the second wireless frame according to the first indication information; the transceiver is also used to send the second wireless frame to the second station STA associated with the second access point AP. In the embodiment of the present application, the transceiver receives the first wireless frame sent by the first access point AP, and the determination unit further determines the transmission end time of the second wireless frame according to the first indication information in the first wireless frame, so that multiple second access points AP can end transmission at the same time, that is, there will be no situation where one AP is sending and another AP is receiving, which reduces interference between APs and between STAs.

[0040] The eleventh aspect of the embodiment of the present application provides a device for channel information detection, which is applied to the first station STA side, including: a transceiver, which is used to receive a broadcast frame sent by a first access point AP, the broadcast frame includes identification information of a second access point AP, and the broadcast frame is used to trigger the first station STA to detect the channel between the second access point AP and the first station STA, and the first station STA is associated with the first access point AP. A determination unit is used to determine the channel quality information of the target channel according to the wireless frame sent by the received target AP, the target channel is the channel between the target AP and the first station STA, and the target AP is included in the second access point AP. The transceiver is also used to send a feedback frame to the first access point AP, and the feedback frame includes the channel quality information of the target channel. In the embodiment of the present application, the channel quality information of the target channel fed back by the first station STA enables the first access point AP to select a suitable MCS when scheduling the first station STA for transmission, so as to achieve a balance between the transmission rate and the packet loss rate.

[0041] The twelfth aspect of the embodiment of the present application provides a device for channel information detection, which is applied to the first access point AP side, including: a transceiver, which is used to send a broadcast frame to the first station STA associated with the first access point AP, the broadcast frame carries the identification information of the second access point AP, and the broadcast frame is used to trigger the first station STA to detect the channel between the second access point AP and the first station STA; receive a feedback frame sent by the first station STA, the feedback frame carries the channel quality information of the target channel detected by the first station STA, the target channel is the channel between the target AP and the first station STA, and the target AP is included in the second access point AP. In the embodiment of the present application, the transceiver triggers the first station STA to detect the channel between the second access point AP and the first station STA through a broadcast frame, and receives the channel quality information of the target channel that can be detected by the second access point AP fed back by the first station STA, so that the first access point AP can predict the signal-to-interference ratio of the first station STA according to the channel quality information of the target channel, and then when scheduling the first station STA for transmission, the first access point AP can select a suitable MCS to achieve a balance between the transmission rate and the packet loss rate.

[0042] The thirteenth aspect of the embodiment of the present application provides a communication device, which has the function of implementing the first access point AP behavior or the second access point AP behavior in the above method design. The function can be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions. The module can be software and / or hardware.

[0043] In a possible implementation manner, the communication device includes a storage unit, a processing unit, and a communication unit.

[0044] Among them, the storage unit is used to store the program code and data required by the communication device; the processing unit is used to call the program code to control and manage the actions of the communication device; and the communication unit is used to support the communication between the communication device and other devices.

[0045] In one possible implementation, the structure of the communication device includes a processor, a memory, a baseband circuit, a radio frequency circuit, an antenna and a bus, wherein the processor, the memory, the baseband circuit, the radio frequency circuit and the antenna are connected via the bus; the memory stores corresponding operation instructions; the processor controls the operation of the radio frequency circuit, the baseband circuit and the antenna by executing the above operation instructions, thereby supporting the first access point AP or the second access point AP to perform the corresponding functions in the above method.

[0046] Another aspect of the embodiments of the present application provides a site, which has the function of implementing the site in the above method embodiment. The function can be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions.

[0047] Another aspect of an embodiment of the present application provides a site, comprising: a processor, a memory, a bus, a transmitter and a receiver; the memory is used to store computer execution instructions, the processor is connected to the memory through the bus, and when the site is running, the processor executes the computer execution instructions stored in the memory, so that the site performs a channel information prediction method as any one of the fifth aspects above.

[0048] Another aspect of the embodiments of the present application provides a device, the device includes a memory, the memory is used to store instructions. When the instructions stored in the memory are executed by the processor, the processor is supported to implement the first access point AP or the second access point AP or the first station STA to perform the corresponding functions in the above method, such as sending or processing the data and / or information involved in the above method. The device may include a chip, or may include a chip and other discrete devices.

[0049] Another aspect of an embodiment of the present application provides a system, which includes the first access point AP of the first aspect and the second access point AP of the second aspect; or, includes the first access point AP of the third aspect and the second access point AP of the fourth aspect; or, includes the first station STA of the fifth aspect and the first access point AP of the sixth aspect; or, includes the first access point AP of the seventh aspect and the second access point AP of the eighth aspect; or, includes the first access point AP of the ninth aspect and the second access point AP of the tenth aspect; or, includes the first access point AP of the eleventh aspect and the second access point AP of the twelfth aspect.

[0050] Another aspect of the embodiments of the present application provides a computer-readable storage medium, in which instructions are stored. When the computer-readable storage medium is run on a computer, the computer executes the methods described in the above aspects.

[0051] Another aspect of the embodiments of the present application provides a computer program product comprising instructions, which, when executed on a computer, enables the computer to execute the methods described in the above aspects.

[0052] It can be seen from the above technical solution that in the embodiment of the present application, the first access point AP sends a first wireless frame to the second access point AP, so that at least one second access point AP can simultaneously send a second wireless frame with the same transmission duration to the second station STA according to the first wireless frame, and synchronization of multiple access points AP is achieved by sending control information, that is, there will be no situation where one AP is sending and another AP is receiving, thereby reducing interference between APs and STAs. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1a is a schematic diagram of an exemplary co-BF technology in the prior art;

[0054] Figure 1b An exemplary system architecture diagram provided for an embodiment of the present application;

[0055] Figure 2a A flowchart of an exemplary method for coordinated transmission of multiple access points (APs) provided in an embodiment of the present application;

[0056] Figure 2b A schematic diagram of an exemplary frame format of a first wireless frame provided in an embodiment of the present application;

[0057] Figure 2c A schematic diagram of another exemplary frame format of a first wireless frame provided in an embodiment of the present application;

[0058] Figure 2d An exemplary synchronous and aligned transmission schematic diagram provided for an embodiment of the present application;

[0059] Figure 2e Another exemplary synchronous and aligned transmission schematic diagram provided for an embodiment of the present application;

[0060] Figure 2f An exemplary transmission diagram provided for an embodiment of the present application;

[0061] Figure 3a A flowchart of an exemplary multi-AP coordinated transmission method provided in an embodiment of the present application;

[0062] Figure 3b Another exemplary synchronous and aligned transmission schematic diagram provided for an embodiment of the present application;

[0063] Figure 3c Another exemplary synchronous and aligned transmission schematic diagram provided for an embodiment of the present application;

[0064] Figure 4a A flowchart of an exemplary multi-AP coordinated transmission method provided in an embodiment of the present application;

[0065] Figure 4b An exemplary downlink alignment transmission schematic diagram provided for an embodiment of the present application;

[0066] Figure 4c Another exemplary downlink alignment transmission schematic diagram provided in an embodiment of the present application;

[0067] Figure 4d Another exemplary downlink alignment transmission schematic diagram provided in an embodiment of the present application;

[0068] Figure 5a A flowchart of an exemplary information prediction method provided in an embodiment of the present application;

[0069] Figure 5b An exemplary transmission diagram provided for an embodiment of the present application;

[0070] Figure 5c A frame structure diagram of an exemplary Trigger frame defined in the standard;

[0071] Figure 5d This is a schematic diagram of exemplary information included in the common information field Common info in the trigger frame Trigger;

[0072] Figure 5e This is a schematic diagram of the information that may be included in the User Info field in the Trigger frame;

[0073] Figure 5f A schematic diagram of an exemplary frame structure of a broadcast frame provided in an embodiment of the present application;

[0074] Figure 5g A schematic diagram of an exemplary frame structure of a feedback frame provided in an embodiment of the present application;

[0075] Figure 5h A schematic diagram of a frame structure of another exemplary feedback frame provided in an embodiment of the present application;

[0076] Figure 5i A schematic diagram of a frame structure of another exemplary feedback frame provided in an embodiment of the present application;

[0077] Figure 6 A schematic diagram of the structure of an exemplary apparatus for multi-AP coordinated transmission provided in an embodiment of the present application;

[0078] Figure 7 A schematic structural diagram of another exemplary apparatus for multi-AP coordinated transmission provided in an embodiment of the present application. DETAILED DESCRIPTION

[0079] The embodiments of the present application provide a method and related apparatus for coordinated transmission of multiple APs, which are used to solve the problem of occupying more channel resources when obtaining CSI in the prior art.

[0080] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0081] The present application embodiment provides a method for coordinated transmission of multiple APs, which can be applied to a wireless local area network, such as Figure 1b As shown, it is an exemplary system architecture diagram provided by an embodiment of the present application, in which the system includes at least two wireless access points AP1 and AP2, and two stations STA1 and STA2, wherein STA1 is a station associated with AP1, and STA2 is a station associated with AP2. In the embodiment of the present application, the coordination between the transmissions of each AP and the associated STA can be achieved by exchanging control information between the first AP1 and the second AP2, so as to solve the problem of occupying more channel resources when obtaining CSI in the prior art and reduce transmission interference.

[0082] It is understandable that the number of APs and STAs in the above-mentioned WLAN communication system is only exemplary and does not constitute a limitation on the embodiments of the present application. It is understandable to those skilled in the art that the AP involved in the embodiments of the present application is a device deployed in a wireless communication network to provide wireless communication functions for sites, and can be used as the hub of a WLAN. For example, the AP can be a base station, a router, a gateway, a repeater, etc., wherein the base station can include various forms of macro base stations, micro base stations, relay stations, etc. Correspondingly, the STA involved in the embodiments of the present application can be an appropriate device connected to a distributed network via a wireless link. For example, STA can be a user terminal, a user device, an access device, a mobile station, a user equipment or other names, where the user terminal can include various handheld devices with wireless communication functions, vehicle-mounted devices, wearable devices (such as smart watches, smart bracelets, etc.), computing devices or other processing devices connected to a wireless modem, as well as various forms of user equipment (UE), mobile station (MS), terminal, terminal equipment, portable communication devices (such as cellular GPRS phones), handsets, portable computing devices, entertainment devices, gaming devices or systems, global positioning system devices, ultra wide band (UWB) devices, wireless devices or any other suitable devices configured for network communication via a wireless medium.

[0083] Among them, the embodiments of the present application may have a variety of multi-AP coordinated transmission methods based on different scenarios. Among them, the multi-AP coordinated transmission in the embodiments of the present application refers to two or more APs cooperating with each other through interactive control information to schedule wireless resources.

[0084] The method of multi-AP coordinated transmission includes the following methods:

[0085] Method A: Synchronize and align transmission of multiple APs during downlink transmission.

[0086] Method B: Synchronize and align the transmission of multiple STAs during uplink transmission.

[0087] Method C: Align transmission of multiple APs during downlink transmission.

[0088] It should be noted that the synchronous transmission in the embodiment of the present application can be understood as multiple transceivers starting to transmit their respective wireless frames at the same time, and the clocks of the multiple transceivers are synchronized. For example, the multiple transceivers include AP01 and AP02, and the clocks of AP01 and AP02 are synchronized. The synchronous transmission between AP01 and AP02 means that AP01 starts to send wireless frame 01 at time A, and AP02 also starts to send wireless frame 02 at time A.

[0089] The aligned transmission in the embodiment of the present application can be understood as multiple transceivers ending transmission of their respective wireless frames at the same time, and the clocks of the multiple transceivers are synchronized. For example, the multiple transceivers include AP03 and AP04, and the clocks of AP03 and AP04 are synchronized. The aligned transmission between AP03 and AP04 means that AP03 ends sending wireless frame 03 at time B, and AP04 also ends sending wireless frame 04 at time B.

[0090] It can be understood that synchronous and aligned transmission means that multiple transceivers start transmitting their respective radio frames at the same time and end transmitting their respective radio frames at the same time. For example, multiple transceivers include AP01 and AP02, and the clocks of AP01 and AP02 are synchronized. Synchronous transmission between AP01 and AP02 means that AP01 starts transmitting radio frame 01 at time C and ends transmitting radio frame 01 at time D. AP02 also starts transmitting radio frame 02 at time C and ends transmitting radio frame 02 at time D.

[0091] The above-mentioned various methods will be described below in conjunction with specific embodiments.

[0092] See also Figure 2a , introduces the method embodiment of the present application to perform multi-AP coordinated transmission through method A. For ease of understanding, it can be combined with Figure 1bThe system framework diagram shown in the figure briefly describes this embodiment, and the method may include:

[0093] AP1 sends control information to AP2. After receiving the control information, AP2 sends data to STA2 at a certain interval, such as 4ms. It should be noted that when AP2 includes multiple APs, the interval between each AP2 receiving the control information and sending the data is the same, and the transmission duration of the sent data is also the same. That is, the time when multiple APs start sending data is the same, the transmission duration of the sent data is also the same, and the time to end sending data is also the same, which can achieve synchronous and aligned transmission of multiple APs during downlink transmission. Among them, AP1 can also synchronize with multiple AP2s.

[0094] The following will be explained based on specific steps:

[0095] 201. A first AP accesses a channel.

[0096] In this embodiment, the AP that initiates multi-AP coordination is called the first AP, and the AP that interacts with the first AP is called the second AP. Since the Wi-Fi frequency band is an unlicensed frequency band, multiple APs should access the channel in a competitive manner to send wireless frames. It can be described in the following two cases: Case 1, a certain AP is selected as the first AP; Case 2, any AP may be the first AP.

[0097] In one example of case 1, the selected AP, i.e., the first AP, successfully competes for the channel and sends a first wireless frame through the channel, and the first wireless frame can be used to initiate multi-AP coordinated transmission. In another example, if the first AP fails to compete for the channel, the AP that successfully competes for the channel sends a request frame to the first AP, and the request frame is used to request the first AP to access the channel and send the first wireless frame through the channel.

[0098] In an example of situation 2, any AP can compete for the channel through the channel access method, and the AP that successfully competes is the first AP to send the first wireless frame, thereby triggering multi-AP coordinated transmission. It can be understood that whichever AP competes for the channel is the first AP to send the first wireless frame.

[0099] Among them, in the embodiments of the present application, there are multiple ways for the AP to compete for channels. In one example, a channel access method based on carrier sense multiple access with collision avoidance (CSMA / CA) is used to compete for channels; in another example, the AP can also compete for channels based on a request to send / clear to send (RTS / CTS) channel access mechanism or based on a point coordination function (PCF), etc., which are not limited here.

[0100] 202. The first AP determines the second AP.

[0101] When it is necessary to reduce the interference between cells through coordination between multiple APs, the first AP can determine the second AP that participates in the coordination. In this embodiment, there are multiple bases for the first AP to determine the second AP. In one example, the first AP obtains the received signal strength indication (RSSI) of the adjacent AP, and determines the AP corresponding to the RSSI whose value is included in the first numerical interval as the second AP. The adjacent AP can be understood as an AP that can communicate with the first AP; in another example, the first AP determines the physical distance between the first AP and the adjacent AP, and selects the second AP from them, so that the value of the physical distance between the first AP and the second AP is within the second numerical interval; in another example, the first AP can also determine the thin AP among the adjacent APs as the second AP. The so-called thin AP can be understood in this embodiment as an AP that needs to be managed, debugged and controlled by the wireless controller, that is, the thin AP cannot work independently and needs to be used in conjunction with the wireless controller; in another example, the first AP can also determine the second AP based on business demand information. Therefore, the specific way in which the first AP determines the second AP is not limited here. It can be understood that the second AP can be one or more APs.

[0102] It should be noted that, in actual applications, this step is an optional step, that is, the first AP may also involve all neighboring APs in the coordination.

[0103] 203. The first AP generates a first wireless frame.

[0104] The first AP generates a first wireless frame, which is used to initiate coordinated transmission of multiple APs. It should be noted that in order to achieve synchronous and aligned transmission of multiple APs during downlink transmission, the first wireless frame at least includes first indication information, which is used to indicate the transmission duration of the second wireless frame to the second AP.

[0105] It should be noted that the transmission duration in the embodiment of the present application can be understood as the time from the start of a transceiver sending a wireless frame to the completion of the wireless frame sending. The transmission duration is related to the size of the wireless frame. In practical applications, the transmission duration can also have other names, such as transmission delay, etc., which are not limited here. Among them, the transmission duration can be directly indicated by a period of time, or by the sending time and end time of the wireless frame, which are not limited here.

[0106] In this embodiment, the first AP generates the first wireless frame so that after receiving the first wireless frame, the second AP sends the second wireless frame to the second STA associated with the second AP at a first time interval to achieve synchronization of multiple APs. The first time interval may be a predefined short inter-frame space (SIFS) or may be customized by the first AP. When the first time interval is customized by the first AP, the first wireless frame may also include indication information of the first time interval.

[0107] Optionally, in order to indicate which second APs participate in the coordinated transmission initiated by the first AP, the first wireless frame may further include second indication information, and the second indication information is used to indicate the identification information of the second AP, so that after the second AP receives the first wireless frame, it determines whether it needs to participate in the multi-AP coordinated transmission according to the second indication information. It should be noted that, in this embodiment, the identification information of the second AP may have multiple situations. In one example, the identification information of the second AP may be the media access control (MAC) address of the second AP; in another example, the identification information of the second AP may be a partial MAC address of the second AP; in another example, the first AP may be the address assigned by the second AP, or the address determined by the second AP itself and indicated to the first AP, so that the first AP includes the address in the first wireless frame, or the identification information of the device (which may be a STA or AP) that has a coupling relationship with the second AP, so that after the device receives the frame sent by the first AP to the second AP, it forwards it to the second AP through the internal interface between the device and the second AP. Therefore, the identification information of the second AP is not specifically limited here.

[0108] Optionally, the first AP may also instruct the second AP to perform channel monitoring within a first time period after receiving the first wireless frame. If the second AP monitors that the channel between the second AP and the second STA is in an idle state within the first time period after receiving the first wireless frame, the second AP may send a second wireless frame to the associated second STA. Conversely, if the channel between the second AP and the second STA is in an occupied state, the second AP does not send the second wireless frame. Therefore, the first wireless frame may also include a third indication information, which is used to indicate whether the second AP needs to monitor the channel between the second AP and the second STA before sending the second wireless frame to the second STA. In one example, a 1-bit channel sensing (CS) indication bit may be set in the first wireless frame. For example, when the CS indication bit is set to 1, it indicates that the second AP needs to perform channel monitoring and only sends the second wireless frame to the second STA when the channel between the second AP and the second STA is idle. When the CS indicator bit is set to 0, it indicates that the second AP does not need to perform channel monitoring, that is, after receiving the first wireless frame, the second AP sends a second wireless frame to the second STA at an interval of the first duration regardless of whether the channel between the second AP and the second STA is idle.

[0109] Optionally, in order to implement the function of joint resource management, the first radio frame may also carry some control information to help the second AP perform radio resource management, for example:

[0110] Since the transmission of the first AP and the transmission of the second AP are performed on the same channel, in order to reduce the interference of the second AP to the first STA associated with the first AP, the first wireless frame may carry fourth indication information, and the fourth indication information is used to indicate the transmission power information of each second AP. The transmission power information may be the maximum transmission power or the transmission power configured by the first AP for the second AP, so that the interference value received by the first STA from the second AP is within a third numerical range, where the third numerical range may be predefined.

[0111] Optionally, in order to allow the second AP to predict the interference value of the first AP to the second STA before sending the second radio frame, the first radio frame may also carry fifth indication information, where the fifth indication information is used to indicate the transmission power information of the first AP.

[0112] Optionally, in order to reduce the interference of the second STA to the first AP, the first radio frame may carry sixth indication information, and the sixth indication information is used to indicate the tolerable maximum interference threshold information of the first AP, so that the second AP determines the power indication information of each associated second STA according to the sixth indication information. The power indication information can be used for each second STA to determine the maximum transmit power. In addition, the power indication information can be included in the second radio frame sent by the second AP to the second STA. In a possible implementation, the tolerable maximum interference threshold information can be the value of the spatial reuse parameter (SRP), and the SRP can be used for the second AP to adjust the transmit power when performing spatial multiplexing transmission, so the second AP can set the transmission parameters of the associated second STA according to the value of the SRP. Correspondingly, in order to allow the second AP to predict the interference value received from the first STA when the second AP receives the radio frame sent by the second STA before sending the second radio frame, the first radio frame can carry the seventh indication information and the eighth indication information, the seventh indication information is used to indicate the identification information of the first STA, and the eighth indication information is used to indicate the transmit power information of the first STA.

[0113] Optionally, in order to ensure that the second AP has enough time to prepare for data transmission after receiving the first wireless frame, the first wireless frame can be lengthened so that after the second AP decodes and obtains the indication information contained in the first wireless frame, it still has a certain amount of time to prepare data until the first wireless frame transmission is completed. In one example, a padding field is added to the first wireless frame, and invalid information is filled in the padding field. Therefore, the first wireless frame may include ninth indication information to indicate the length of the padding field. For ease of understanding, as shown in FIG. Figure 2b As shown, it is a schematic diagram of the frame format of an exemplary first wireless frame provided in an embodiment of the present application, wherein each AP information field (AP info field) may include an AP ID field and other information (other information) fields after the AP ID field. In one example, an AP info field may be used as a fill field, and the AP ID of the fill field may be set to a special AP ID field, such as all 1s or all 0s, to indicate the beginning of the fill field. When the second AP detects the special AP ID field, it can determine that the subsequent other information field is invalid information for filling, so the second AP can prepare data within the time it takes to receive the fill field. Figure 2cAs shown, a frame format diagram of an exemplary first wireless frame provided in this embodiment, in which the AP info field adjacent to the frame check sequence (FCS) can be understood as a fill field, wherein the APID in the AP info field = special value, and the other information field (Other information) after the AP ID field in the AP information field contains invalid (useless) other information fields.

[0114] Optionally, in order to better manage wireless resources, the first AP can also perform centralized scheduling to determine the transmission parameters of the second AP, that is, the first AP allocates and indicates resource scheduling information to the second AP. Therefore, the first wireless frame can also carry tenth indication information, which is used to indicate resource scheduling information, so that the second AP determines the channel resources used to send the second wireless frame according to the resource scheduling information. Among them, the resource scheduling information may include but is not limited to a combination of one or more of the following information: resource block (resource unit, RU) allocation information of each second AP, identification information of the site scheduled by the second AP (that is, identification information of the second STA), modulation and coding scheme (MCS) used by each site or spatial stream used by each site.

[0115] Optionally, since there are different application scenarios in actual applications, such as uplink transmission and downlink transmission, the first wireless frame in the embodiment of the present application may include an eleventh indication information, and the eleventh indication information is used to indicate uplink transmission or downlink transmission. In one example, a 1-bit uplink and downlink indication bit may be set in the first wireless frame. For example, when the uplink and downlink indication bits are set to 0, it indicates that uplink transmission is required, that is, the second AP triggers the second STA to send a wireless frame to the second AP. When the uplink and downlink indication bits are set to 1, it indicates that downlink transmission is required, that is, the second AP needs to send a wireless frame to the second STA. It should be noted that in this embodiment, the eleventh indication information is used to indicate downlink transmission.

[0116] Optionally, in view of the fact that the present application also provides a variety of coordinated transmission modes, such as synchronous transmission, aligned transmission, synchronous and aligned transmission, etc., the first AP may indicate a specific transmission mode to the second AP before the second AP participates in the coordinated transmission, wherein the first AP may have the following indication methods, including:

[0117] The first wireless frame includes twelfth indication information, and the twelfth indication information is used to indicate whether synchronous transmission is required. In this embodiment, the twelfth indication information is used to indicate that synchronous transmission is required. It should be noted that if the twelfth indication information indicates that multiple APs do not need synchronous transmission, that is, the second AP does not need to start transmission at the same time, then the second AP can decide the time to start transmission by itself, and the second AP can perform aligned transmission or not.

[0118] Optionally, the first wireless frame may further include thirteenth indication information, which is used to indicate whether aligned transmission is required. If the thirteenth indication information indicates that multiple APs do not need aligned transmission, that is, the second APs do not need to end transmission at the same time, the second APs may decide the end time of transmission by themselves.

[0119] In some specific scenarios, such as when the distance between APs is far and the distance between STAs is also far, it is possible to allow for neither synchronous transmission nor aligned transmission. In this embodiment, the first AP indicates to the second AP that neither synchronous transmission nor aligned transmission is possible, and the first wireless frame may include both the twelfth indication information and the thirteenth indication information. The twelfth indication information is used to indicate that multiple APs do not need synchronous transmission, and the thirteenth indication information is used to indicate that multiple APs do not need aligned transmission.

[0120] Optionally, the first wireless frame includes fourteenth indication information, and the fourteenth indication information is used to indicate the mode of multi-AP coordinated transmission. In one example, a 2-bit transmission indication bit can be set in the first wireless frame. For example, when the transmission indication bit is 01, it indicates that synchronous transmission is required. When the transmission indication bit is 10, it indicates that aligned transmission is required. When the transmission indication bit is 00, it indicates neither synchronous transmission nor aligned transmission. When the transmission indication bit is 11, it indicates synchronous and aligned transmission. Therefore, the specific indication method is not limited in this application.

[0121] Optionally, if the first AP determines that neither synchronous transmission nor aligned transmission is performed, the first AP may instruct the second AP to set the ACK policy to block ACK (BA) when sending the second radio frame to the second STA, so that the second STA will not respond to the BA frame immediately after receiving the second radio frame, but will respond to the BA frame after receiving the block ACK request (BAR) frame sent by the second AP, thereby reducing the interference caused by the second STA also sending the BA frame when the second AP sends the data frame. For example, the first AP instructs the second AP to send the second radio frame to the second STA, and during the sending period of the second radio frame, the first AP sends the third radio frame to the first STA associated with the first AP, that is, the sending time of the second radio frame may be different from the sending time of the third radio frame, and the end time of the second radio frame may be different from the end time of the third radio frame, but the sending period of the second radio frame and the third radio frame may have an intersection. Among them, the sending period in the embodiment of the present application can be understood as the time period corresponding to the start of a transceiver sending a radio frame to the completion of the sending of the radio frame. For example, the transceiver starts sending a wireless frame at time A and ends sending the wireless frame at time B, then time A to time B is the sending period of the wireless frame. Therefore, for ease of understanding, let the sending period of the second wireless frame be [time 1, time 2], and the sending period of the third wireless frame be [time 3, time 4], and time 3 is earlier than time 1, and time 4 may not be equal to time 2, so there is an intersection between the sending period of the second wireless frame and the sending period of the third wireless frame. In order to avoid one AP sending a wireless frame while another AP is receiving a confirmation frame, the first AP instructs the second AP to set an ACK policy, so that after the second STA receives the second wireless frame, it will not immediately reply with a confirmation frame, but after the first wireless frame and the second wireless frame are both sent, the second AP sends a confirmation frame request to the second STA, and the second STA then sends a confirmation frame to the second AP.

[0122] Therefore, the first radio frame may also carry fifteenth indication information, where the fifteenth indication information is used to indicate that the ACK policy is carried in the second radio frame.

[0123] In summary, in addition to the first indication information, the first radio frame may also carry multiple indication information, which may be specifically shown in Table 1.

[0124] Table 1

[0125]

[0126]

[0127] For ease of description, in this embodiment, the information that the first AP needs to indicate to the second AP is referred to as information to be indicated. The information to be indicated includes at least the first indication information, and the information to be indicated may also include, but is not limited to, a combination of one or more of the indication information shown in Table 1. It should be noted that the information to be indicated may be entirely included in the first radio frame. For example, if the information to be indicated includes the first indication information to the fourth indication information, the first radio frame includes the first indication information to the fourth indication information. In an example, the other information in the information to be indicated except the first indication information may not be entirely included in the first radio frame. For example, if the information to be indicated includes the first indication information to the fourth indication information, after the first AP determines the second AP participating in the coordinated transmission, it sends a control frame to the second AP, and the control frame includes the second indication information and the third indication information. When the first AP competes for the channel, it sends a first radio frame to the second AP to trigger the transmission of multiple APs, and the first radio frame includes the first indication information and the fourth indication information. Therefore, the way in which the first AP sends the information to be indicated to the second AP is not limited here.

[0128] It should be noted that, in the present embodiment, the first AP accesses the channel through step 201, determines the second AP and generates the first wireless frame through steps 202 and 203, and there is no sequence of steps between the two processes, and step 201 may be executed first, or step 202 and step 203 may be executed first, or they may be executed simultaneously, and the specific sequence is not limited here.

[0129] 204. The second AP receives the first wireless frame sent by the first AP.

[0130] After the first AP accesses the channel, it sends the generated first wireless frame to the determined second AP to initiate coordinated transmission of multiple APs, so that after the second AP receives the first wireless frame, it sends the second wireless frame to the second STA associated with the second AP at a first interval, wherein the transmission duration of the second wireless frame is the transmission duration indicated by the first indication information. And the first duration can be a customized duration of the first AP or a preset duration.

[0131] It should be noted that in order to improve data transmission efficiency and reduce the bit error rate, in actual applications, the transmitting end, i.e., the first AP in this embodiment, can sequentially encode, modulate, map into frames, perform inverse fast Fourier transform, and add a cyclic prefix (CP) to the first wireless frame, and then transmit it to the receiving end, i.e., the second AP in this application, through a channel. Correspondingly, after the second AP receives the first wireless frame sent by the first AP, it sequentially performs CP removal, fast Fourier transform, data extraction, channel estimation, equalization, demodulation, and decoding processing on the received first wireless frame. In this application, the decoding operation of the encoded first wireless frame can adopt existing technical means, which will not be described in detail in this application.

[0132] In addition, as described in step 203, the first radio frame may include multiple indication information, and the second AP participates in the coordinated transmission of multiple APs according to each indication information in the first radio frame, as follows:

[0133] The second AP determines, according to the first indication information, a transmission duration of a second radio frame sent to the second STA.

[0134] Optionally, when the first wireless frame includes second indication information, the second AP determines to participate in the multi-AP coordinated transmission initiated by the first AP according to the second indication information.

[0135] Optionally, when the first wireless frame includes the third indication information, the second AP determines whether it is necessary to monitor the channel between the second AP and the second STA before sending the second wireless frame based on the third indication information. If the third indication information indicates that the channel needs to be monitored, the second AP determines whether to send the second wireless frame based on the state of the monitored channel, that is, it does not send when the channel is busy, otherwise it sends. If the third indication information indicates that it is not necessary to monitor the channel, the second AP directly sends the second wireless frame to the second STA at an interval of the first duration after receiving the first wireless frame.

[0136] Optionally, when the first wireless frame includes the fourth indication information, the second AP determines the transmission power information of the second AP according to the fourth indication information, wherein the transmission power information may be the maximum transmission power or the transmission power configured by the first AP. Therefore, in this embodiment, when the second AP sends the second wireless frame, the transmission power used does not exceed the maximum transmission power. Or the transmission power used is the transmission power configured by the first AP.

[0137] Optionally, when the first wireless frame includes the fifth indication information, the second AP obtains the transmit power information of the first AP according to the fifth indication information, and then the second AP predicts the interference value received by the associated second STA from the first AP according to the transmit power information of the first AP. In actual applications, the prediction can be made by the following formula: Interference value of the first AP to the second STA = transmit power of the first AP - path loss value from the first AP to the second STA. It can be understood that other methods can also be used for prediction in actual applications, which are not limited here.

[0138] Optionally, when the first radio frame includes the sixth indication information, the second AP obtains the tolerable maximum interference threshold information of the first AP according to the sixth indication information, and determines the power indication information of each second STA based on the maximum interference threshold information, so that each second STA determines the maximum transmit power of the second STA through the power indication information, that is, controls the transmit power of each second STA so that the interference value of the second STA to the first AP is within the fourth numerical range. Therefore, in this embodiment, the transmit power of the second STA when sending a BA in response to the second radio frame cannot exceed the maximum transmit power of the second STA. In an example, the second AP can determine the average interference value of each second STA to the first AP according to the maximum interference threshold information. For example, the value of the tolerable maximum interference threshold information of the first AP is 5mw, and there are 5 second STAs associated with the second AP. The second AP can assume that the average interference value of each second STA to the first AP shall not be greater than 5mw / 5=1mv, and then the second AP can determine the maximum transmit power of the second STA according to the average interference value of each second STA to the first AP. It should be noted that, in the present application, in an optional manner, the second AP can directly predict the maximum transmit power of the second STA and indicate it to the second STA. In another optional manner, the second AP can indicate power indication information to the second STA, such as the maximum interference value of the second STA to the first AP, so that the second STA determines the maximum transmit power of the second STA according to the power indication information, that is, through the power indication information sent by the second AP, the second STA can directly obtain the maximum transmit power of the second STA, and can also further calculate the maximum transmit power of the second STA according to the power indication information.

[0139] Optionally, when the first wireless frame includes the seventh indication information and the eighth indication information, the second AP determines the interference value of each first STA to the second AP based on the identification information of the first STA in the seventh indication information and the transmission power of the first STA in the eighth indication information.

[0140] Optionally, when the first wireless frame includes the ninth indication information, the second AP determines the length of the padding field used to fill the invalid information through the ninth indication information, that is, the second AP can prepare data to be sent to the second STA within the length of the padding field. In another example, the first wireless frame may also include a special AP ID field to indicate the beginning of the padding field. When the second AP detects the special AP ID field, the second AP can prepare data to be sent to the second STA within the length of the padding field.

[0141] Optionally, when the first wireless frame includes the tenth indication information, the second AP determines the channel resources used to send the second wireless frame through the resource scheduling information indicated by the tenth indication information, wherein the resource scheduling information may include but is not limited to a combination of one or more of the following information: resource block (resource unit, RU) allocation information of each second AP, identification information of the site scheduled by the second AP (i.e., identification information of the second STA), the MCS used by each site or the spatial stream used by each site.

[0142] Optionally, when the first wireless frame includes the eleventh indication information, the second AP determines whether to perform uplink transmission or downlink transmission through the eleventh indication information. In this embodiment, the eleventh indication information is used to indicate downlink transmission, that is, triggering the second AP to send a second wireless frame to the second STA. The second wireless frame can be a data frame or a control frame.

[0143] Optionally, when the first wireless frame includes the twelfth indication information, the second AP determines whether synchronous transmission is required through the twelfth indication information. In this embodiment, the twelfth indication information is used to indicate the need for synchronous transmission. That is, after each second AP receives the first wireless frame, it sends a second wireless frame to the second STA at a preset time interval, thereby realizing synchronous transmission of multiple APs.

[0144] Optionally, when the first wireless frame includes the thirteenth indication information, the second AP determines whether aligned transmission is required through the twelfth indication information. In this embodiment, the thirteenth indication information is used to indicate that aligned transmission is required.

[0145] Optionally, when the first wireless frame includes the fourteenth indication information, the second AP may determine the multi-AP coordinated transmission mode through the fourteenth indication information. In this embodiment, the fourteenth indication information is used to indicate synchronous and aligned transmission.

[0146] Optionally, when the thirteenth indication information indicates that aligned transmission is not required or the fourteenth indication information indicates neither synchronous transmission nor aligned transmission, the first wireless frame may also include the fifteenth indication information, the second AP carries the ACK policy in the second wireless frame through the fifteenth indication information, so that the second STA does not respond to the BA frame immediately after receiving the second wireless frame, but responds to the BA frame after receiving the BAR frame sent by the second AP.

[0147] Optionally, after receiving the first wireless frame sent by the first AP, the second AP also sends a first confirmation frame in response to the first wireless frame to the first AP. It should be noted that when there are multiple second APs, there are also multiple corresponding first confirmation frames. Therefore, in order to achieve synchronous and aligned transmission of multiple first confirmation frames, the first wireless frame can also include the transmission duration of the first confirmation frame, so that after receiving the first wireless frame, multiple second APs send first confirmation frames to the first AP at the same interval.

[0148] 205. The second AP sends a second radio frame to the second STA.

[0149] In this embodiment, after receiving the first radio frame, the second AP sends a second radio frame to the second STA at an interval of the first duration.

[0150] The manner in which the second AP sends the second radio frame to the second STA according to the indication information included in the first radio frame is as described in step 204 and will not be repeated here.

[0151] 206. The first AP sends a third wireless frame to the first STA.

[0152] After the first AP sends the first radio frame to the second AP, the first AP sends the third radio frame to the first STA associated with the first AP during the sending period of the second radio frame, and in order to achieve alignment of downlink frames sent by multiple APs, the transmission duration of the third radio frame is equal to the transmission duration of the second radio frame. In this embodiment, in order to achieve synchronization of downlink frames sent by multiple APs, after sending the first radio frame, the first AP also sends the third radio frame to the first STA at an interval of the first duration, that is, the sending time of the third radio frame is the same as the sending time of the second radio frame, so as to achieve synchronization of the second radio frame and the third radio frame.

[0153] Optionally, the third wireless frame may also include an ACK policy, so that the first STA does not immediately respond to the third confirmation frame (which can be understood as a BA) after receiving the third wireless frame, but responds after receiving a BAR frame sent by the first AP.

[0154] It should be noted that, in this embodiment, this step is an optional step, that is, the first AP may not send the third wireless frame to the first STA, but only trigger multiple second APs to send second wireless frames to the second STA, thereby achieving synchronous and aligned transmission of multiple second APs.

[0155] For ease of understanding, the following two situations are described separately based on diagrams:

[0156] 1. The first AP sends a third wireless frame to the first STA.

[0157] like Figure 2d As shown, it is a schematic diagram of synchronous transmission provided by this embodiment. Figure 2d In the figure, the first AP sends a first radio frame to the second AP, namely the SYNC frame in the figure, and then sends a third radio frame to the first STA at an interval of T ms, namely Data1 in the figure. Optionally, the first AP receives a third confirmation frame sent by the first STA to respond to the third radio frame, namely BA1 in the figure. After receiving the SYNC frame, the second AP sends a second radio frame to the second STA at an interval of T ms, namely Data2 in the figure, and receives a second confirmation frame sent by the second STA to respond to the second radio frame, namely BA2 in the figure. It can be understood that since the start transmission time of Data1 and Data2 is the same, and the transmission duration of Data1 and Data2 is the same, the transmission end time of Data1 and Data2 is also the same, thereby achieving synchronous and aligned transmission of multiple APs.

[0158] 2. The first AP does not send the third wireless frame to the first STA.

[0159] like Figure 2e FIG. 2 is another schematic diagram of synchronous transmission provided by this embodiment. Figure 2e In the figure, the first AP sends the first wireless frame, i.e., the SYNC frame in the figure, to the second AP, and then does not send any wireless frame. After receiving the SYNC frame, the second AP (1) sends the second wireless frame, i.e., Data1 in the figure, to the second STA (1) at an interval of Tms, and receives the second confirmation frame, i.e., BA1 in the figure, sent by the second STA (1). After receiving the SYNC frame, the second AP (2) also sends Data2 to the second STA (2) at an interval of Tms, and receives BA2 sent by the second STA (2). It can be understood that since the start transmission time of Data1 and Data2 is the same, and the transmission duration of Data1 and Data2 is the same, the transmission end time of Data1 and Data2 is also the same, thereby achieving synchronous and aligned transmission of multiple APs.

[0160] 207. The second STA sends a second confirmation frame to the second AP.

[0161] After receiving the second radio frame sent by the second AP, the second STA sends a second confirmation frame in response to the second radio frame to the second AP.

[0162] Optionally, when the second wireless frame includes power indication information of the second STA, the second STA determines the maximum transmit power of the second STA according to the power indication information, and the transmit power of the second confirmation frame sent by the second STA cannot be greater than the maximum transmit power.

[0163] Optionally, when the second radio frame includes an ACK policy, the second STA sends the second confirmation frame to the second AP only after receiving the BAR frame sent by the second AP.

[0164] It should be noted that, in actual applications, this step is an optional step, that is, after receiving the second wireless frame, the second STA may not send the second confirmation frame.

[0165] 208. The first STA sends a third confirmation frame to the first AP.

[0166] Optionally, after receiving the third radio frame sent by the first AP, the first STA sends a third confirmation frame in response to the third radio frame to the first AP.

[0167] Optionally, when the third wireless frame includes an ACK policy, the first STA sends the third confirmation frame to the first AP only after receiving the BAR frame sent by the first AP.

[0168] It should be noted that, in this embodiment, in addition to realizing synchronous and aligned transmission of downlink wireless frames, synchronous and aligned transmission of uplink confirmation frames can also be realized, for example, synchronous and aligned transmission of the second confirmation frame and the third confirmation frame is realized, and for example, when the first AP does not send the third wireless frame or the first AP sends the third wireless frame but the first STA does not send the third confirmation frame, synchronous and aligned transmission between multiple second confirmation frames is realized, as follows:

[0169] The first wireless frame may also include the transmission duration of the second confirmation frame, so that after the second AP obtains the transmission duration of the second confirmation frame, it can indicate the transmission duration of the second confirmation frame to the second STA through the second wireless frame, so that after receiving the second wireless frame, the second STA sends the second confirmation frame to the second AP at an interval of the second duration. It should be noted that, similar to the first duration, the second duration can be preset or customized by the first AP, so the second duration can be the same as or different from the first duration, and the specifics are not limited here.

[0170] Optionally, when the first AP sends the third wireless frame, the third wireless frame may include the transmission duration of the third confirmation frame, so that after receiving the third wireless frame, the first STA sends the third confirmation frame to the first AP at an interval of the second duration. It should be noted that the transmission duration of the third confirmation frame is equal to the transmission duration of the second confirmation frame.

[0171] In summary, this embodiment can realize synchronous and aligned transmission between confirmation frames, and there will be no situation where one STA sends a confirmation frame while another STA receives a data frame or a control frame sent by the AP, thereby reducing mutual interference between the STA and the AP.

[0172] It should be noted that, in the embodiment of the present application, sending a wireless frame and receiving a confirmation frame in response to the wireless frame can be referred to as a transmission, and in the present embodiment, the first wireless frame can trigger not only one synchronous and aligned transmission, but also multiple synchronous and aligned transmissions. Figure 2f As shown, an exemplary transmission schematic diagram provided for this embodiment realizes synchronization and alignment of multiple transmissions through the first wireless frame. The time occupied by each transmission can be called a time segment (TS), so the first wireless frame can include indication information for each time segment. It can be understood that the indication information for each time segment can include the first indication information, and a combination of one or more of the second indication information to the sixteenth indication information. In one example, the indication information for each time period can be different. For example, the transmission duration of Data11 in time segment1 is different from the transmission duration of Data21 in time segment2. Alternatively, the indication information for each time period can be the same, such as the first wireless frame can include periodic indication information, so that multiple APs use the same indication information for synchronized and aligned transmission every other time segment.

[0173] In the embodiment of the present application, through the sending process and signaling of multi-AP coordinated scheduling, multi-AP coordinated parallel synchronous downlink transmission is achieved, interference is reduced, and throughput is improved.

[0174] superior Figure 2a Downlink synchronous transmission is described below. Figure 3a , introduces the method embodiment of the present application to coordinate multiple APs to achieve uplink synchronization and aligned transmission through method B. For ease of understanding, it can be combined with Figure 1b The system framework diagram shown in the figure briefly describes this embodiment, and the method may include:

[0175] AP1 sends control information to AP2. After receiving the control information, AP2 sends trigger information to STA2 at interval A. After STA2 receives the trigger information, it sends data to AP2 at interval B. It should be noted that when AP2 includes multiple APs, there can also be multiple associated STA2s. Among them, the interval between each AP2 receiving the control information and sending the trigger information is duration A, and the transmission duration of the trigger information sent by each AP2 is also the same, so the moment when each STA2 receives the trigger information is also the same. And the interval between each STA2 receiving the trigger information and sending the data is duration B, and the transmission duration of the data sent by each STA2 is also the same, so the time when each STA2 ends sending the data is also the same. Therefore, multiple STA2s start transmitting data at the same time and end transmitting data at the same time, so that the synchronous transmission of multiple STAs during uplink transmission can be achieved. Among them, STA1 can also receive the trigger information of AP1 to synchronize with multiple AP2s.

[0176] The following will be explained based on specific steps:

[0177] 301. A first AP accesses a channel.

[0178] 302. The first AP determines the second AP.

[0179] In this embodiment, steps 301 to 302 are Figure 2a The steps 201 to 202 are similar and will not be described in detail here.

[0180] 303. The first AP generates a first wireless frame.

[0181] In this embodiment, in order to realize synchronous transmission of uplink data, the first AP generates a first radio frame, so that after receiving the first radio frame, the second AP sends a second radio frame to the second STA at an interval of a first duration. The second radio frame triggers the second STA to send a third radio frame to the second AP at an interval of a second duration after receiving the second radio frame. In this embodiment, the second radio frame can be a trigger frame, and the third radio frame can be a data frame sent by the second STA. It should be noted that the first duration and the second duration can both be preset, or both customized by the first AP. When the first duration and the second duration are customized by the first AP, the first radio frame can also include indication information of the first duration and indication information of the second duration. Therefore, the second duration can be the same as or different from the first duration, and is not specifically limited here.

[0182] In order to coordinate the uplink synchronization and alignment transmission of multiple APs, the first wireless frame at least includes the first indication information and the sixteenth indication information, the first indication information is used to indicate the transmission duration of the second wireless frame, and the first indication information is used to indicate the transmission duration of the second wireless frame. Figure 2aThe first indication information included in the first wireless frame is similar to that in the first wireless frame, and the details are not repeated here. In addition, the sixteenth indication information is used to indicate the transmission duration of the third wireless frame sent by the second STA. It can be understood that in order to indicate the transmission duration of the third wireless frame to the second STA, the second wireless frame sent by the second AP to the second STA may also include the transmission duration of the third wireless frame.

[0183] and Figure 2a Similar to the first radio frame generated in step 203 shown in the figure, the first radio frame generated by step 303 in this embodiment may also include but is not limited to one or more combinations of the indication information shown in Table 2:

[0184] Table 2

[0185]

[0186] Among them, the second to eighth indication information and Figure 2a The second indication information to the eighth indication information contained in the first wireless frame are similar and will not be described in detail here.

[0187] The eleventh indication information is used to instruct the second AP to perform uplink transmission, that is, it is necessary to trigger the second STA to send a third wireless frame to the second AP.

[0188] Among them, the 112th to 14th instructions are Figure 2a The twelfth to fourteenth indication information contained in the first wireless frame are similar and will not be described in detail here.

[0189] Among them, if the first AP determines neither synchronous transmission nor aligned transmission, the fifteenth indication information is used to indicate the ACKpolicy, that is, the second AP will not respond to the confirmation frame immediately after receiving the third wireless frame, but will respond after receiving the BAR frame sent by the second STA.

[0190] It should be noted that, in this embodiment, the first AP accesses the channel through step 301, determines the second AP and generates the first wireless frame through steps 302 and 303, and there is no order of steps between these two processes. Step 301 can be executed first, or step 302 and step 303 can be executed first, or they can be executed simultaneously, and the specific details are not limited here.

[0191] 304. The second AP receives the first wireless frame sent by the first AP.

[0192] In this embodiment, step 304 and Figure 2a Step 204 in the illustrated embodiment is similar and will not be described in detail here.

[0193] 305. The second AP sends a second radio frame to the second STA.

[0194] In this embodiment, step 305 and Figure 2a Step 205 in the illustrated embodiment is similar and will not be described in detail here.

[0195] It should be noted that the second radio frame in this embodiment is used to trigger the second STA to send the third radio frame to the second AP, and the second radio frame may include the transmission duration of the third radio frame. Figure 2a In the illustrated embodiment, the second STA may be a data frame sent by the second AP to the second STA.

[0196] 306. The second STA sends a third radio frame to the second AP.

[0197] After receiving the second radio frame sent by the second AP, the second STA sends a third radio frame to the second AP at an interval of a second time period, where the second time period may be SIFS.

[0198] Optionally, when the second radio frame includes power indication information of the second STA, the second STA determines the maximum transmission power of the second STA according to the power indication information, and the power of the second STA sending the third radio frame cannot be greater than the maximum transmission power.

[0199] 307. The second AP sends a third confirmation frame to the second STA.

[0200] After receiving the third radio frame sent by the second STA, the second AP sends a third confirmation frame in response to the third radio frame to the second STA.

[0201] Optionally, when the first wireless frame includes an ACK policy, the second AP sends the third confirmation frame to the second STA only after receiving a BAR frame sent by the second STA.

[0202] Optionally, when the first wireless frame includes fifth indication information to indicate the transmit power information of the second AP, and the transmit power information may be the maximum transmit power or the transmit power configured by the first AP, when the second AP sends the third confirmation frame, the power used cannot exceed the maximum transmit power of the second AP, or the power used is the transmit power configured by the first AP.

[0203] It should be noted that this step is an optional step, that is, in actual applications, after the second AP receives the third wireless frame sent by the second STA, it may not send a third confirmation frame in response to the third wireless frame to the second STA.

[0204] 308. The first AP sends a fourth radio frame to the first STA.

[0205] After the first AP sends the first wireless frame to the second AP, the first AP sends a fourth wireless frame to the first STA associated with the first AP during the sending period of the second wireless frame. The fourth wireless frame is used to trigger the first STA to send a fifth wireless frame to the first AP at an interval of a second time after receiving the fourth wireless frame, and the fourth wireless frame must include the transmission duration of the fifth wireless frame. In addition, in order to achieve alignment of uplink frames sent by multiple STAs, the transmission duration of the fourth wireless frame is equal to the transmission duration of the second wireless frame, and the transmission duration of the fifth wireless frame is equal to the transmission duration of the third wireless frame.

[0206] It should be noted that, in this embodiment, in order to achieve synchronization between the fourth wireless frame and the second wireless frame, the first AP sends the fourth wireless frame to the first STA during the sending period of the second wireless frame, that is, after the first AP sends the first wireless frame, it also sends the fourth wireless frame to the first STA at an interval of the first time length, so that the sending time of the fourth wireless frame is the same as the sending time of the second wireless frame.

[0207] It should be noted that Figure 2a The step 206 shown is similar and will not be described again here.

[0208] For ease of understanding, the following two situations are described separately based on diagrams:

[0209] 1. The first AP sends a fourth wireless frame to the first STA.

[0210] like Figure 3b FIG. 1 is another schematic diagram of synchronous and aligned transmission provided by this embodiment. Figure 3b In the figure, the first AP sends the first radio frame to the second AP, namely the SYNC frame in the figure, and then sends the fourth radio frame to the first STA at an interval of T ms, namely the Trigger1 frame in the figure, and receives the fifth radio frame sent by the first STA at an interval of P ms, namely Data1 in the figure. After receiving the SYNC frame, the second AP sends the second radio frame to the second STA at an interval of T ms, namely Trigger2 in the figure, and receives the third radio frame sent by the second STA at an interval of P ms, namely Data2 in the figure. It can be understood that since the start transmission time of Data1 and Data2 is the same, and the transmission duration of Data1 and Data2 is the same, the transmission end time of Data1 and Data2 is also the same, thus achieving synchronous transmission of uplink data.

[0211] 2. The first AP does not send the fourth wireless frame to the first STA.

[0212] like Figure 3c FIG. 1 is another exemplary synchronous and aligned transmission schematic diagram provided by this embodiment. Figure 3cIn the figure, the first AP sends the first radio frame to the second AP, namely the SYNC frame in the figure, and then does not send any radio frame. After receiving the SYNC frame, the second AP (1) sends the second radio frame to the second STA (1) at an interval of T ms, namely Trigger1 in the figure, and receives the third radio frame sent by the second STA (1) at an interval of P ms, namely Data1 in the figure. After receiving the SYNC frame, the second AP (2) also sends Trigger2 to the second STA (2) at an interval of T ms, and receives Data1 sent by the second STA (2) at an interval of P ms. It can be understood that since the start transmission time of Data1 and Data2 is the same, and the transmission duration of Data1 and Data2 is the same, the transmission end time of Data1 and Data2 is also the same, thereby achieving synchronous and aligned transmission of uplink data.

[0213] 309. The first STA sends a fifth radio frame to the first AP.

[0214] Optionally, after the first STA receives the fourth radio frame sent by the first AP, it sends a fifth radio frame to the second AP at an interval of a second time length.

[0215] 310. The first AP sends a fifth confirmation frame to the first STA.

[0216] Optionally, after receiving the fifth radio frame sent by the first STA, the first AP may send a fifth confirmation frame in response to the fifth radio frame to the first STA.

[0217] Optionally, the first AP may set an ACK policy so that the first AP sends the fifth acknowledgment frame to the first STA only after receiving the BAR frame sent by the first STA.

[0218] It should be noted that, in this embodiment, in addition to realizing the synchronous and aligned transmission of the uplink wireless frame, the synchronous and aligned transmission of the downlink confirmation frame can also be realized, that is, the synchronous and aligned transmission of the third confirmation frame and the fifth confirmation frame or the synchronous and aligned transmission between multiple third confirmation frames is realized, as follows:

[0219] The first wireless frame may also include fifteenth indication information, which is used to indicate the transmission duration of the third confirmation frame, so that the second AP sends a third confirmation frame to the second STA at a third duration after receiving the third wireless frame. It should be noted that the third duration may be a preset duration or customized by the first AP. If customized by the first AP, the first wireless frame may also include indication information of the third duration.

[0220] Optionally, after receiving the fifth wireless frame, the first AP also sends a fifth confirmation frame to the first STA at a third time interval, and it should be noted that the transmission duration of the fifth confirmation frame is equal to the transmission duration of the third confirmation frame.

[0221] In summary, this embodiment can realize the synchronous and aligned transmission confirmation frames of the first AP and the second AP, and there will be no situation where one AP sends a confirmation frame while the other AP receives a data frame sent by the STA, thereby reducing the interference between the AP and the STA.

[0222] and Figure 2a Similar to the first wireless frame in the embodiment shown, the first wireless frame in this embodiment can also trigger multiple synchronous transmissions, and the triggering method is the same as Figure 2a The manner of triggering the first radio frame in the illustrated embodiment is similar and will not be described in detail here.

[0223] In the embodiment of the present application, synchronous transmission of uplink data is achieved through the transmission process and signaling of multi-AP coordinated scheduling, interference is reduced, and throughput is improved.

[0224] superior Figure 2a and Figure 3a Synchronous and aligned transfers are described below. Figure 4a , introduces the method embodiment of the present application to coordinate multiple APs to achieve downlink aligned transmission through method C. For ease of understanding, it can be combined with Figure 1b The system framework diagram shown in the figure briefly describes this embodiment, and the method includes:

[0225] AP1 sends control information to AP2. After receiving the control information, AP2 sends data to STA2 and ends sending the data at time C. It should be noted that when AP2 includes multiple APs, the end time of each AP2 sending data to the associated STA2 is time C. That is, the end time of multiple APs sending data is the same, which can achieve the aligned transmission of multiple APs during downlink transmission. Among them, AP1 can also be aligned with AP2.

[0226] The following will be explained based on specific steps:

[0227] 401. A first AP accesses a channel.

[0228] 402. The first AP determines the second AP.

[0229] In this embodiment, steps 401 to 402 are Figure 2a The steps 201 to 202 are similar and will not be described in detail here.

[0230] 403. The first AP generates a first wireless frame.

[0231] The first AP generates a first wireless frame, and the first wireless frame is used to trigger the second AP to send a second wireless frame to the second STA associated with the second AP to initiate coordinated scheduling of multiple APs. It should be noted that in order to achieve alignment of multiple APs during downlink transmission, the first wireless frame includes at least first indication information, and the first indication information is used to enable the second AP to determine the transmission end time of the second wireless frame.

[0232] It should be noted that, depending on the wireless frame sent by the first AP, the first indication information included in the first wireless frame may also be different, which will be described below respectively:

[0233] Scenario 1: The first AP sends a first wireless frame to the second AP and the first STA.

[0234] For easier understanding, see Figure 4b , is an exemplary downlink alignment transmission schematic diagram provided by this embodiment based on scenario one. In the figure, the first AP sends a first wireless frame to the first STA, namely Data1 in the figure. The Data1 carries first indication information, and the first indication information can be used to indicate the transmission duration of Data1, or the transmission end time of Data1. Therefore, the second AP obtains the first indication information from Data1 to determine the transmission end time of Data1, and sends a second wireless frame to the second STA, namely Data2 in the figure, so that the transmission end time of Data2 is the same as the transmission end time of Data1, thereby realizing the alignment of downlink data transmission. Optionally, after receiving Data1 sent by the first AP, the first STA sends a BA1 frame to the first AP. After receiving Data2 sent by the second AP, the second STA sends a BA2 frame to the first AP.

[0235] Therefore, in this scenario, the first indication information is used to indicate the transmission duration of the first wireless frame or the transmission end time of the first wireless frame, so that the second AP determines the transmission end time of the second wireless frame according to the first indication information, and the transmission end time of the second wireless frame is the same as the transmission end time of the first wireless frame.

[0236] Scenario 2: The first AP sends a first wireless frame to the second AP, and then sends a third wireless frame to the associated first STA.

[0237] For easier understanding, see Figure 4c, is an exemplary downlink alignment transmission schematic diagram provided by this embodiment based on scenario 2. In the figure, the first AP sends a first wireless frame to the second AP, namely, the SYNC frame in the figure, and sends a third wireless frame to the first STA, namely, Data1 in the figure, wherein the SYNC frame carries first indication information, and the first indication information can be used to indicate the transmission duration of Data1, or the transmission end time of Data1. Therefore, the second AP determines the transmission end time of Data1 according to the first indication information, and sends a second wireless frame to the second STA, namely, Data2 in the figure, so that the transmission end time of Data2 is the same as the transmission end time of Data1, thereby realizing the alignment of downlink data transmission. Optionally, after receiving Data1 sent by the first AP, the first STA sends a BA1 frame to the first AP. After receiving Data2 sent by the second AP, the second STA sends a BA2 frame to the first AP.

[0238] Therefore, in this scenario, the first indication information is used to indicate the transmission duration of the third wireless frame or the transmission end time of the third wireless frame, so that the second AP determines the transmission end time of the second wireless frame according to the first indication information, and the transmission end time of the second wireless frame is the same as the transmission end time of the third wireless frame.

[0239] Scenario 3: The first AP sends a first wireless frame to the second AP.

[0240] For easier understanding, see Figure 4d , is an exemplary downlink alignment transmission schematic diagram provided by this embodiment based on scenario three. In the figure, the first AP sends a first wireless frame to the second AP, namely, the SYNC frame in the figure, to trigger multiple second APs to send second wireless frames, namely, Data in the figure, such as triggering the second AP (1) to send Data1, triggering the second AP (2) to send Data2, wherein the first wireless frame carries first indication information, and the first indication information can be used to indicate the transmission end time of the Data sent by each second AP. It should be noted that, in order to achieve alignment of downlink data transmission, the transmission end time of the Data sent by each second AP is the same. Optionally, after the second STA (1) receives Data1 sent by the second AP (1), it sends a BA1 frame to the second AP (1). After the second STA (2) receives Data2 sent by the second AP (2), it sends a BA2 frame to the second AP (2).

[0241] Therefore, in this scenario, the first indication information is used to indicate the transmission end time of the second wireless frame, so that multiple second APs determine the transmission end time of each second wireless frame according to the first indication information, and the transmission end time of each second wireless frame is the same.

[0242] and Figure 2aSimilar to the first radio frame generated in step 203 shown in the figure, the first radio frame generated by step 403 in this embodiment may also include but is not limited to one or more combinations of the indication information shown in Table 3:

[0243] Table 3

[0244]

[0245] Among them, the second indication information to the eleventh indication information and the fifteenth indication information are Figure 2a The second indication information to the eleventh indication information contained in the first wireless frame are similar to the fifteenth indication information, and the details are not repeated here.

[0246] The twelfth indication information is used to instruct the second AP to perform transmission without synchronization, that is, multiple APs can decide the time to start transmission by themselves, as long as the transmission end time is the same.

[0247] The thirteenth indication information is used to indicate that transmission needs to be aligned, that is, the transmission end times of multiple APs need to be the same.

[0248] Among them, the fourteenth indication information is used to indicate that synchronous transmission is not required, but synchronous alignment is required.

[0249] It should be noted that, in the present embodiment, the first AP accesses the channel through step 401, determines the second AP and generates the first wireless frame through steps 402 and 403, and there is no sequence of steps between the two processes, and step 401 may be executed first, or step 402 and step 403 may be executed first, or they may be executed simultaneously, and the specific sequence is not limited here.

[0250] 404. The second AP receives the first wireless frame sent by the first AP.

[0251] In the scenario 1 described in step 403 of this embodiment, the first indication information in the first radio frame is used to indicate the transmission duration of the first radio frame or the transmission end time of the first radio frame. When the first indication information is used to indicate the transmission duration of the first radio frame, the second AP determines the transmission end time of the first radio frame according to the transmission start time of the first radio frame and the transmission duration of the first radio frame, and determines the transmission end time of the first radio frame as the transmission end time of the second radio frame sent to the second STA. When the first indication information is used to indicate the transmission end time of the first radio frame, the second AP directly uses the transmission end time of the first radio frame as the transmission end time of the second radio frame sent to the second STA.

[0252] It should be noted that, in order to facilitate the second AP to quickly detect the indication information in the first radio frame, the indication information may be carried in the physical layer preamble of the physical layer protocol data unit where the first radio frame is located.

[0253] In scenario 2 described in step 403 of this embodiment, the first indication information is used to indicate the transmission duration of the third wireless frame or the transmission end time of the third wireless frame. The way in which the second AP determines the transmission end time of the second wireless frame based on the first indication information is similar to the way in which the transmission end time of the second wireless frame is determined in scenario 1, and the details are not repeated here.

[0254] In scenario three described in step 403 of this embodiment, the first indication information is used to indicate the transmission end time of the second radio frame, and the second AP directly obtains the transmission end time of the second radio frame according to the first indication information.

[0255] Optionally, when the first wireless frame further includes but is not limited to one or more combinations of the second indication information to the fifteenth indication information in Table 3, the second AP receives the first wireless frame and processes it in the same manner as Figure 2a The step 204 shown is similar and will not be described in detail here.

[0256] Optionally, in this embodiment, after receiving the first wireless frame sent by the first AP, the second AP also sends a first confirmation frame in response to the first wireless frame to the first AP. When there are multiple second APs, there are also multiple corresponding first confirmation frames. Therefore, in order to achieve aligned transmission of multiple first confirmation frames, the first wireless frame may also include the transmission end time of the first confirmation frame, so that after receiving the first wireless frame, multiple second APs send multiple first confirmation frames with the same transmission end time to the first AP.

[0257] 405. The second AP sends a second radio frame to the second STA.

[0258] In this embodiment, step 405 and Figure 2a The step 205 shown is similar and will not be described in detail here.

[0259] It should be noted that, in this embodiment, the second AP determines the transmission end time of the second wireless frame to be sent. Figure 2a In step 205, the second AP also determines the transmission start time of the second radio frame.

[0260] 406. The first AP sends a fourth radio frame to the first STA.

[0261] As described in the scenarios 1 to 3 in step 403, this step is an optional step, and the following describes this step based on three scenarios respectively:

[0262] Scenario 1: The first AP sends the first radio frame to the first STA, that is, the fourth radio frame is the first radio frame.

[0263] After the first AP generates the first wireless frame, it sends the first wireless frame to the associated first STA, and the first wireless frame also needs to be sent to the second AP to instruct the second AP to perform downlink transmission alignment. The transmission end time of the first wireless frame is the same as the transmission end time of the second wireless frame.

[0264] Optionally, the indication information in the first wireless frame may be carried in a physical layer preamble code of the first wireless frame.

[0265] Scenario 2: The first AP sends the third radio frame to the first STA, that is, the fourth radio frame is the third radio frame.

[0266] After the first AP sends the first wireless frame to the second AP, it sends the third wireless frame to the associated first STA, and the first indication information in the first wireless frame is used to indicate the transmission duration or transmission end time of the third wireless frame, so that the transmission end time of the second wireless frame sent by the second AP is the same as the transmission end time of the third wireless frame.

[0267] Scenario 3: The first AP does not send a wireless frame to the first STA.

[0268] In this scenario, the first AP may not send a radio frame to the first STA, but only trigger multiple second APs to send second radio frames and implement aligned transmission of multiple second radio frames.

[0269] 407. The second STA sends a second confirmation frame to the second AP.

[0270] 408. The first STA sends a fourth confirmation frame to the first AP.

[0271] In this embodiment, steps 407 to 408 are Figure 2a Steps 207 to 408 are similar and will not be described in detail here.

[0272] It should be noted that, in this embodiment, in addition to realizing the aligned transmission of downlink radio frames, the aligned transmission of uplink confirmation frames can also be realized, for example, the aligned transmission of the second confirmation frame and the fourth confirmation frame, or the aligned transmission between multiple second confirmation frames, as follows:

[0273] The first wireless frame may also include the transmission end time of the second confirmation frame, so that after the second AP obtains the transmission end time of the second confirmation frame, it can indicate the transmission end time of the second confirmation frame to the second STA through the second wireless frame, so that after receiving the second wireless frame, the second STA sends a second confirmation frame to the second AP, and the transmission end time of the second confirmation frame is as indicated by the first wireless frame.

[0274] Optionally, after the first AP sends the fourth wireless frame to the first STA, the fourth wireless frame may include a transmission end time of a fourth confirmation frame, wherein the transmission end time of the fourth confirmation frame is the same as the transmission end time of the second confirmation frame.

[0275] In summary, this embodiment can achieve aligned transmission between confirmation frames, and there will be no situation where one STA is sending a confirmation frame while another STA is receiving a data frame or a control frame, thereby reducing interference between STAs and interference between APs.

[0276] and Figure 2a Similar to the first wireless frame in the embodiment shown, the first wireless frame in this embodiment can also trigger multiple alignment transmissions, and the triggering method is the same as Figure 2a The manner of triggering the first radio frame in the illustrated embodiment is similar and will not be described in detail here.

[0277] In the embodiment of the present application, through the sending process and signaling of multi-AP coordinated scheduling, multi-AP coordinated parallel aligned downlink transmission is achieved, interference is reduced, and throughput is improved.

[0278] It should be understood that, given a signal to interference ratio (SIR), when the MCS selected by the transmitter is too high, packet loss may occur because the SIR of the receiver cannot reach the SIR required by the high MCS. When the MCS selected by the transmitter is too low, although the probability of packet loss is very low, the low MCS makes the data transmission rate low and the channel cannot be fully utilized. Therefore, in order to facilitate coordinated scheduling of multiple APs, each AP should know how high the SIR associated with each AP can obtain when multiple APs transmit in parallel, so that the AP can select the appropriate MCS when scheduling the STA to transmit.

[0279] Therefore, in an embodiment of the present application, a channel information prediction method is provided to predict the SIR of a site during multi-AP coordinated scheduling, and then allocate a suitable MCS to achieve a balance between transmission rate and packet loss rate. Figure 5a , is a flowchart of an exemplary information prediction method provided in an embodiment of the present application, including:

[0280] 501. The first AP sends a broadcast frame.

[0281] The first AP sends a broadcast frame to all STAs associated with the first AP, and the broadcast frame is used to indicate to the STAs associated with the first AP a second AP for which signal quality detection is required, wherein the broadcast frame carries identification information of the second AP. It should be noted that the second AP includes at least one AP, and the second AP may include the first AP.

[0282] In this embodiment, the identification information of the second AP may be in various situations. In one example, the identification information of the second AP may be the MAC address of the second AP. In another example, the identification information of the second AP may be a partial MAC address of the second AP, or an address assigned by the first AP to the second AP, or an address determined by the second AP itself and indicated to the first AP, so that the first AP includes the address in the broadcast frame, or the identification information of a device (which may be a STA or an AP) coupled with the second AP, so that after the device receives the frame sent by the first AP to the second AP, it forwards it to the second AP through the internal interface between the device and the second AP. Therefore, the identification information of the second AP is not specifically limited here.

[0283] For ease of description, in this embodiment, any one or more of the STAs associated with the first AP are referred to as first STAs, so the first AP sends a broadcast frame to the first STA to trigger the first STA to detect the channel between the second AP and the first STA.

[0284] In this embodiment, the broadcast frame may use existing management frames of the 802.11 standard such as a beacon frame (Beacon), a Probe Request frame, etc., or may use a non-standard manufacturer-defined frame format, etc., which is not specifically limited here.

[0285] It should be noted that the second AP in this embodiment can also receive the broadcast frame sent by the first AP.

[0286] 502. The first STA receives a wireless frame sent by a target AP.

[0287] In this embodiment, the AP that can communicate with the first STA is called a target AP. It can be understood that the target AP is part or all of the second AP. Therefore, the first STA receives the wireless frame sent by the target AP to detect the channel between the first STA and the target AP.

[0288] It should be noted that, in this embodiment, the wireless frame received by the first STA may be sent by the target AP autonomously, or may be sent by the target AP after being triggered by the first AP, which will be described below respectively:

[0289] Example 1: The wireless frame is sent autonomously by the target AP.

[0290] In this example, the wireless frame may be a beacon frame sent by the target AP, and the beacon frame may be used to measure the path loss from the target AP to the beacon frame receiver (i.e., the first STA). The beacon frame may carry a measurement report of the target AP itself, and the measurement report may include but is not limited to one or more of the following information: the transmit power of the target AP, and the signal reception level and power of the devices around the target AP.

[0291] Example 2: The wireless frame is sent by the target AP after being triggered by the first AP.

[0292] In this example, the broadcast frame in step 501 can also be used to trigger the second AP to sequentially send null data packets (NDP), and the broadcast frame also includes sequence indication information, which is used to indicate the sequence in which the second AP sends NDP frames. It should be noted that the broadcast frame can be an enhanced-null data packet announcement (E-NDPA) frame.

[0293] Therefore, after receiving the broadcast frame sent by the first AP, the second AP sends NDP frames in sequence according to the sequence indication information in the broadcast frame, wherein the inter-frame interval may be SIFS. It should be noted that the inter-frame interval may be a default interval or customized by the first AP. When the first AP customizes it, the broadcast frame also carries the indication information of the inter-frame interval. For ease of understanding, please refer to Figure 5b , is an exemplary transmission diagram provided by this embodiment. In the figure, AP1 broadcasts an E-NDPA frame (which can be understood as a broadcast frame), so AP1~AP3 send NDP frames in sequence according to the order indicated in the E-NDPA frame, such as AP1 sends NDP1 frame first, AP2 sends NDP2 frame, and AP3 sends NDP3 frame last. Optionally, AP1 can also send a trigger frame to trigger the first STA to send a feedback frame. Therefore, after the first STA receives the Trigger frame, it feeds back the corresponding Feedback1 frame~Feedback3 frame according to the received NDP1 frame~NDP3 frame.

[0294] Optionally, the broadcast frame may further include identification information of a STA that needs to detect a channel. The identification information of the STA that needs to detect a channel may be a MAC address or an IP address.

[0295] Therefore, the difference between the above two examples is that in Example 1, the first STA receives the wireless frame (such as a beacon frame) autonomously sent by the second AP, and then detects the channel according to the received signal strength of the beacon frame. In Example 2, each second AP sends NDP frames in the order indicated by the first AP, so that the first AP detects the channel according to the received NDP frames.

[0296] 503. The first STA determines channel quality information of the target channel according to the radio frame.

[0297] It should be noted that when example 2 in step 502 is adopted, that is, the wireless frame can be an NDP frame, the first STA also needs to determine the target AP based on the received NDP frame, including: the first STA obtains the order in which the second AP sends NDP frames based on the second indication information in the broadcast frame, and determines the target AP that sends the wireless frame through the order of the received wireless frames. For example, AP1 first sends NDP1, and then AP2 sends NDP2, and AP3 sends NDP3... When the first STA receives the second NDP, namely NDP2, it can be determined based on the order in which the second AP sends NDP frames that the target AP that sends the second NDP is AP2.

[0298] Therefore, after the first STA receives the wireless frame sent by the target AP, it determines the channel quality information of the target channel (i.e., the channel between the first STA and the target AP) according to the wireless frame. Specifically, the first STA can obtain the received signal strength indication (RSSI) of the target AP or the transmit power of the target AP according to the measurement report of the target AP carried by the wireless frame. Therefore, the channel quality information of the target channel determined by the first STA can be the RSSI of the target AP, the transmit power of the target AP, or the path loss between the target AP and the first STA. Therefore, in this embodiment, the channel quality information of the target channel can contain multiple contents, which are not limited here.

[0299] Optionally, when the channel quality information is the path loss between the target AP and the first STA, the first STA needs to calculate the channel quality information by using the transmit power and RSSI of the target AP. The specific calculation method may be:

[0300] Path loss = TX Power + Gr + Gt - RSSI, where TX Power represents the transmit power of the target AP, Gr represents the receive antenna gain, Gt represents the transmit antenna gain, RSSI represents the signal reception strength of the target AP, and Gr and Gt are preset values. It should be noted that in actual applications, there are many ways to calculate path loss, which will not be described here one by one.

[0301] 504. The first STA receives a trigger frame sent by the first AP.

[0302] Optionally, the first STA may also receive a trigger frame sent by the first AP, where the trigger frame is used to trigger the first STA to send a feedback frame, and the trigger frame may include resource configuration indication information, where the resource configuration indication information is used to indicate the wireless channel resources used by each first STA to reply to the feedback frame, wherein the resource configuration information may include but is not limited to one or more combinations of the following information: RU allocation information of the first STA, spatial and time stream (STS) information or orthogonal code.

[0303] It should be noted that the trigger frame generated by the first AP may be designed based on the Trigger frame defined in the 802.11ax standard, such as Figures 5c to 5e As shown, Figure 5c This is a frame structure diagram of an exemplary Trigger frame defined in the 802.11ax standard. The Trigger frame consists of multiple parts, such as Frame Control, Common info, Userinfo, etc. Figure 5d for Figure 5c The diagram shows the information contained in the Common info section of the Trigger frame. Figure 5e for Figure 5c The diagram shows the information contained in the User Info section of the Trigger frame. Figure 5c As shown, when the value of the Trigger Type subfield in the Common info part of the Trigger frame is different, the function of the Trigger frame is also different, as shown in Table 4, which is an exemplary correspondence table between the value and type of the Trigger Type subfield:

[0304] Table 4

[0305]

[0306] In one example, the value of the Trigger Type subfield can be set to a specific value, for example, the value of the TriggerType subfield is a value between 8 and 15. When the first AP sends the Trigger frame to the first STA, it triggers the first STA to send a feedback frame.

[0307] It should be noted that the first STA determines the channel quality information of the target channel through steps 502 and 503, and the first STA receives the trigger frame sent by the first AP through step 504, and there is no order of steps between these two processes. Steps 502 and 503 can be executed first, or step 504 can be executed first, or both can be executed simultaneously, and the specifics are not limited here.

[0308] 505. The first STA sends a feedback frame to the first AP.

[0309] In response to the trigger frame sent by the first AP, the first STA sends a feedback frame to the first AP, wherein the feedback frame includes channel quality information of the target channel, wherein the target channel is the channel between the first STA and the target AP. It can be understood that the feedback frame includes identification information of the target AP to indicate to the first AP which AP is being detected. The identification information of the target AP may be the MAC address of the target AP.

[0310] Optionally, in this embodiment, in order to reduce the length of the feedback frame, a short ID may be used as the identifier of the target AP. The specific operations are as follows:

[0311] The broadcast frame in step 501 further includes fourth indication information, and the fourth indication information is used to indicate the short ID of each second AP, such as Figure 5f As shown in FIG. 1 , a schematic diagram of the frame structure of an exemplary broadcast frame is shown. In the figure, each AP info field contains a corresponding MAC Address and Feedback ID (i.e., short ID). Therefore, when the first STA sends a feedback frame to the first AP, the feedback frame carries a short ID indication to indicate the identification information of the target AP, such as Figure 5g , which is a schematic diagram of an exemplary frame structure of a feedback frame. In the figure, each AP Feedback info field includes a corresponding Feedback ID (ie, a short ID) and channel quality information (eg, RSSI).

[0312] Optionally, the feedback frame sent by the first STA may contain multiple types of channel quality information, for example, it may include RSSI of the target AP and transmit power information of the target AP, such as Figure 5hAs shown in FIG. 1 , a schematic diagram of an exemplary feedback frame structure is shown. In the figure, each AP Feedback info field includes a corresponding Feedback ID, TX Power, and RSSI, etc. Alternatively, the channel quality information may also directly include the path loss between the first STA and the target AP, where the path loss value is calculated by the first STA using the transmit power and RSSI of the target AP, such as Figure 5i FIG. 4 is a schematic diagram of another exemplary frame structure of a feedback frame. In the figure, each AP Feedback info field includes a corresponding Feedback ID, pathloss, etc.

[0313] Optionally, in Example 2, since the first STA can receive NDP frames from the first AP and the second AP, the first STA can calculate the SIR or interference to signal ratio (ISR) of the second AP based on the received power of the two NDP frames, and carry the SIR or ISR of the second AP in the feedback frame.

[0314] Therefore, the content of the feedback frame sent by the first STA to the first AP is not specifically limited in this embodiment.

[0315] 506. The first AP predicts the SIR of the first STA according to the channel quality information of the target channel.

[0316] After the first AP receives the feedback frame sent by the first STA, the first AP predicts the SIR of the first STA according to the channel quality information of the target channel contained in the feedback frame, wherein the calculation formula of the SIR of the first STA can be: SIR = (transmitting power of the first AP - path loss between the first AP and the first STA) / (transmitting power of the target AP - path loss between the target AP and the first STA), so the first AP can directly or indirectly obtain the path loss between the target AP and the first STA through the channel quality information of the target channel fed back by the first STA, and then calculate the SIR of the first STA.

[0317] Optionally, the first AP may also calculate the ISR of the first STA, where ISR*SIR=1.

[0318] Optionally, the present application may also provide an information prediction method, including: each AP keeps monitoring the channel, obtains the RSSI of each STA (including the STA in this cell and the STA in other cells) according to the monitoring result, and then sends the obtained RSSI information to other APs. After each AP obtains the RSSI information sent by other APs, it can calculate the SIR of each STA during parallel transmission, thereby serving as the input for multi-AP coordinated scheduling transmission. For ease of understanding, for example, assume that there are two APs, AP1 and AP2, where AP1 is associated with STA1 and AP2 is associated with STA2. In historical transmissions, AP1 will monitor the signals of STA1 and STA2, and AP2 will also monitor the signals of STA1 and STA2. After AP1 sends the signal strength of STA1 and STA2 to AP2, if AP2 needs to obtain the SIR of STA2 during parallel transmission, it can be obtained by dividing the signal strength of STA2 monitored by AP2 by the signal strength of STA2 sent by AP1.

[0319] It should be noted that Figure 5a The information prediction method shown can be applied not only to the scenario of the multi-AP coordination method in the embodiment of the present application, but can also be independently applied to other scenarios where information prediction is required before data transmission. Figure 5a The specific application scenarios of the information prediction method provided in practice are not limited here.

[0320] The above describes the multi-AP coordination method in the embodiment of the present application. The following describes in detail the device for multi-access point AP coordinated transmission from the perspective of hardware processing.

[0321] Figure 6 A possible structural diagram of a device 600 for coordinated transmission of multiple access points AP in the above embodiment is shown. The device 600 can be configured as the aforementioned first access point AP. The device 600 may include: a processor 602, a computer-readable storage medium / memory 603, a transceiver 604, an input device 605 and an output device 606, and a bus 601. The processor, the transceiver, the computer-readable storage medium, etc. are connected via a bus. The embodiment of the present application does not limit the specific connection medium between the above components.

[0322] The transceiver 604 may be used to support communication between the first AP and the second access point AP in the above embodiment, and also support communication between the first AP and one or more first STAs associated with the first access point AP in the above embodiment, and may perform Figures 2a to 5iThe transceiver 604 may be used to transmit a first wireless frame to at least the second access point AP, wherein the first wireless frame includes indication information for indicating the transmission duration of the second wireless frame sent by the second AP, and to transmit a third wireless frame to the first station STA during the transmission of the second wireless frame, wherein the transmission duration of the third wireless frame is the same as the transmission duration of the second wireless frame. The transceiver 604 may also perform Figure 2a Step 208, Figure 3a Step 306 and step 310, Figure 4a Step 408 in , and Figure 5a Of course, the transceiver 604 can also be used to execute other processes and methods of the technology described in this application.

[0323] The processor 602 is used to control and manage the actions of the first AP, and is used to execute the processing performed by the first AP in the above embodiment. Figures 2a to 5i The processing process involving the first AP and / or other processes used for the technology described in this application may be responsible for managing the bus and executing programs or instructions stored in the memory. For example, the processor 602 may execute Figure 2a Steps 201 to 203 in Figure 3a Steps 301 to 303 in Figure 4a Steps 401 to 403 in Figure 5a Step 506 in .

[0324] The computer-readable storage medium / memory 603 stores a program, instruction or data for executing the technical solution of the present application. For example, the computer-readable storage medium / memory 603 may include instructions sufficient to allow the device 600 to send a first wireless frame to one or more second APs, and may also include instructions sufficient to allow the device 600 to send a third wireless frame to the first station STA during the transmission period of the second wireless frame, and may also include instructions sufficient to allow the device 600 to implement the above Figures 2a to 5i The process involves the first AP's transceiver process, processing process and / or other processes used for the technology described in this application.

[0325] Understandably, Figure 6 Only a simplified design of the first AP is shown. In actual applications, the first AP may include any number of transceivers, processors, memories, etc., and all first APs that can implement the present application are within the protection scope of the present application.

[0326] Figure 7A possible structural diagram of a device 700 for coordinated transmission of multiple access points AP in the above embodiment is shown. The device 700 can be configured as the aforementioned second AP, and the device 700 includes: a processor 702, a computer-readable storage medium / memory 703, a transceiver 704, an input device 705 and an output device 706, and a bus 701. Among them, the processor, the transceiver, the computer-readable storage medium, etc. are connected through the bus. The embodiment of the present application does not limit the specific connection medium between the above components.

[0327] The transceiver 704 may be used to support communication between the second AP and the first AP, and also support communication between the second AP and one or more second STAs associated with the second access point AP in the above embodiment, and may perform Figures 2a to 4d The communication or interaction process involving the second AP and / or other processes used for the technology described in this application. For example, the transceiver 704 can be used to receive at least a first radio frame sent by the first AP, and can also be used to send a second radio frame to the second STA after the first radio frame. The transceiver 704 is also used to perform Figure 2a Step 204, step 205 and step 207 in Figure 3a Steps 304 to 307 in Figure 4a Of course, the transceiver 904 can also be used to execute other processes and methods of the technology described in this application.

[0328] The processor 702 is used to control and manage the actions of the second AP and to execute the processing performed by the second AP in the above embodiment. Figures 2a to 4d The processing process involving the second AP and / or other processes used for the techniques described in this application may be responsible for managing the bus and may execute programs or instructions stored in the memory.

[0329] The computer-readable storage medium / memory 703 stores programs, instructions, and data for executing the technical solution of the present application. For example, the computer-readable storage medium / memory 703 may include instructions sufficient to allow the device 700 to receive the first wireless frame sent by the first AP, and may also include instructions sufficient to allow the device 700 to send a second wireless frame to the second STA after receiving the first wireless frame, and may also include instructions sufficient to allow the device 700 to implement the above Figures 2a to 4d The process involves the second AP's transceiver process, processing process and / or other processes used for the technology described in this application.

[0330] Understandably, Figure 7Only a simplified design of the second AP is shown. In actual applications, the second AP may include any number of transceivers, processors, memories, etc., and all second APs that can implement the present application are within the protection scope of the present application.

[0331] The processor involved in the above-mentioned device 600 and device 700 can be a general-purpose processor, such as a general-purpose central processing unit (CPU), a network processor (NP), a microprocessor, etc., or an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program of the present application. It can also be a digital signal processor (DSP), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The controller / processor can also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of DSP and microprocessors, and the like. The processor usually performs logical and arithmetic operations based on program instructions stored in a memory.

[0332] The computer-readable storage medium / memory 603 and computer-readable storage medium / memory 703 mentioned above may also store an operating system and other application programs. Specifically, the program may include a program code, and the program code includes a computer operation instruction. More specifically, the above-mentioned memory may be a read-only memory (ROM), other types of static storage devices that can store static information and instructions, a random access memory (RAM), other types of dynamic storage devices that can store information and instructions, a disk storage, and the like. The memory 603 may be a combination of the above-mentioned storage types. And the above-mentioned computer-readable storage medium / memory may be in the processor, or may be outside the processor, or distributed on multiple entities including a processor or a processing circuit. The above-mentioned computer-readable storage medium / memory may be specifically embodied in a computer program product. For example, a computer program product may include a computer-readable medium in a packaging material.

[0333] Alternatively, the apparatus 600 and the apparatus 700 may also be configured as a general processing system, such as a chip, which includes: one or more microprocessors providing processor functions; and an external memory providing at least a portion of a storage medium, all of which are connected to other supporting circuits through an external bus architecture. When the instructions stored in the memory are executed by the processor, the processor executes the first AP in Figures 2a to 4d The multi-AP coordinated transmission method in the embodiment, and Figures 5a to 5i Some or all of the steps in the channel information prediction method in the embodiment, for example Figure 2a Steps 201 to 203 in Figure 3a Steps 301 to 303 in Figure 4a Steps 401 to 403 in Figure 5a Step 506 in, and / or other processes for the technology described in this application. Alternatively, the processor executes the second AP at Figures 2a to 4d Some or all of the steps in the multi-AP coordinated transmission method in the embodiment, and / or other processes for the technology described in this application. Alternatively, the processor executes the first STA in Figures 5a to 5i Some or all of the steps in the channel information prediction method in the embodiment, such as Figure 5a Step 503 in, and / or other processes for the technology described in this application.

[0334] The steps of the method or algorithm described in conjunction with the disclosure of the present application can be implemented in a hardware manner, or can be implemented by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules can be stored in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile hard disk, a CD-ROM or any other form of storage medium well known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an ASIC. In addition, the ASIC can be located in a user device. Of course, the processor and the storage medium can also be present in the user device as discrete components.

[0335] An embodiment of the present application also provides a device, which may be a chip, and may include a memory, wherein the memory is used to store instructions.

[0336] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0337] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0338] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0339] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0340] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), disk or optical disk and other media that can store program codes.

[0341] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application is described in detail with reference to the above embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A multi-access point AP coordinated transmission method, characterized in that: include: The second access point AP receives a first wireless frame sent by the first access point AP, where the first wireless frame includes transmit power information of the second access point AP, where the transmit power information is used to indicate a maximum transmit power of the second access point AP or a transmit power configured by the first access point AP for the second access point AP; During a period in which the first access point AP sends a third wireless frame to a first station STA associated with the first access point AP, the second access point AP sends the second wireless frame to a second station STA associated with the second access point AP based on the transmission power information of the second access point AP.

2. The method according to claim 1, characterized in that The first radio frame includes a sending time and an end time of the second radio frame.

3. The method according to claim 2, characterized in that The sending time of the second radio frame is the same as the sending time of the third radio frame.

4. The method according to claim 2, characterized in that: The sending time of the second radio frame is before the sending time of the third radio frame.

5. The method according to claim 1 or 2, characterized in that: The first wireless frame also includes identification information of the second access point AP.

6. The method according to claim 1 or 2, characterized in that: The first radio frame also carries one or more of the following: The maximum interference threshold information that the first access point AP can tolerate; the identification information of the first station STA; the transmission power information of the first station STA; and the transmission power information of the first access point AP.

7. The method according to claim 1 or 2, characterized in that: The transmission duration of the second radio frame is the same as the transmission duration of the third radio frame.

8. The method according to claim 1 or 2, characterized in that: The first wireless frame further includes eleventh indication information, and the eleventh indication information is used to indicate uplink transmission or downlink transmission.

9. A device for coordinated transmission of multiple access points (AP), the device being applied to a second access point (AP) side, characterized in that: include: a transceiver, configured to receive a first wireless frame sent by a first access point AP, wherein the first wireless frame includes transmit power information of the second access point AP, wherein the transmit power information is used to indicate a maximum transmit power of the second access point AP or a transmit power configured by the first access point AP for the second access point AP; During a period in which the first access point AP sends a third wireless frame to a first station STA associated with the first access point AP, the transceiver is further used to send the second wireless frame to a second station STA associated with the second access point AP based on the transmission power information of the second access point AP.

10. The device according to claim 9, characterized in that The first radio frame includes a sending time and an end time of the second radio frame.

11. The device according to claim 10, characterized in that The sending time of the second radio frame is the same as the sending time of the third radio frame.

12. The device according to claim 10, characterized in that The sending time of the second radio frame is before the sending time of the third radio frame.

13. The device according to claim 9 or 10, characterized in that The first wireless frame also includes identification information of the second access point AP.

14. The device according to claim 9 or 10, characterized in that The first radio frame also carries one or more of the following: The maximum interference threshold information that the first access point AP can tolerate; the identification information of the first station STA; the transmission power information of the first station STA; the transmission power information of the first access point AP.

15. The device according to claim 9 or 10, characterized in that The transmission duration of the second radio frame is the same as the transmission duration of the third radio frame.

16. The device according to claim 9 or 10, characterized in that The first wireless frame further includes eleventh indication information, and the eleventh indication information is used to indicate uplink transmission or downlink transmission.

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