Cooperative transmission method, apparatus and device based on multiple wireless access devices, and medium

Abstract

The invention provides a cooperative transmission method and device based on multiple wireless access devices, equipment and a medium. According to the invention, a plurality of wireless access devices with relatively strong co-channel interference are divided into a cooperative set (i.e., a target cooperative set), and a data transmission strategy of each second wireless access device participating in cooperative transmission is determined through the first wireless access device with the strongest cooperative transmission capability. The first wireless access device can comprehensively consider transmission requirements to determine the optimal data transmission strategy between each second wireless access device and the corresponding target terminal device, so that the problem of co-channel interference existing in multi-AP cooperative transmission in an AP dense deployment scene can be solved; and meanwhile, an access point controller does not need to be introduced, and the conditions that the network construction cost is high and the communication topology complexity is high when a centralized WLAN network architecture is adopted to carry out multi-AP cooperative transmission can also be avoided.

Description

Technical Field

[0001] This application relates to the field of communication technologies, and in particular, to a cooperative transmission method, apparatus, device, and medium based on multiple wireless access devices. Background Art

[0002] With the large-scale popularization of mobile terminals such as smart phones and tablets, and the booming development of the Internet of Things in fields such as smart homes, smart cities, and industrial Internet of Things, a large number of stations (STAs) need to access the network. The wireless local area network (WLAN) has become an ideal solution to meet the needs of high-density device access and flexible networks due to its advantages of high bandwidth and low latency. Among them, a station refers to a wireless device or terminal device in a wireless local area network according to the IEEE 802.11 standard. To provide better signal coverage and network capacity, the deployment of wireless access points (APs) shows an increasingly dense trend. However, the co-channel interference (CCI) problem within overlapping basic service sets (OBSS) becomes more prominent in the scenario of dense deployment of wireless access points.

[0003] The Institute of Electrical and Electronics Engineers (IEEE) defines the new generation of Wi-Fi standard as 802.11be (also known as Wi-Fi 7), and determines multi-AP cooperation as a key technology in the standard. The key to realizing multi-AP cooperation is how to negotiate and cooperate between different APs on the basis of existing technologies such as frequency reuse and spatial reuse of a single AP, so that they can use non-interfering spectrum and spatial resources simultaneously. At present, most of the research on multi-AP cooperation adopts a centralized WLAN network architecture, that is, the access point controller (AC) centrally manages the information transfer and policy execution between the AP and the STA. However, when the number of APs is large, the access point controller needs to process a large amount of device interaction information. Secondly, the centralized WLAN network architecture requires each AP to be able to establish a communication connection with the access point controller, which not only increases the network construction cost but also increases the complexity of the communication topology. Summary of the Invention

[0004] The present application provides a cooperative transmission method, device, equipment and medium based on multiple wireless access devices, which is used to solve the defects of high network construction cost and high complexity of communication topology existing in the prior art when introducing an access point controller, and can also solve the co-channel interference problem existing in the cooperative transmission of multiple APs in the scenario of dense AP deployment.

[0005] The present application provides a cooperative transmission method based on multiple wireless access devices, which is applied to a first wireless access device in a target cooperation set. The target cooperation set includes multiple different wireless access devices, and the co-channel interference among the multiple wireless access devices is greater than a preset interference threshold. The first wireless access device is any one of the wireless access devices in the target cooperation set. The method includes: If it is determined that itself is the wireless access device with the strongest cooperative transmission ability in the target cooperation set, send a cooperative transmission request to the remaining wireless access devices in the target cooperation set; According to the messages returned by the remaining wireless access devices in response to the cooperative transmission request, determine multiple second wireless access devices. The second wireless access device is a wireless access device in the target cooperation set that agrees to participate in the cooperative transmission; Obtain the transmission requirements of each of the second wireless access devices and the target terminal devices involved in the transmission requirements. Each of the wireless access devices is connected to at least one terminal device, and the wireless access device is used to provide wireless local area network access services for the terminal devices; According to the transmission requirements, determine the data transmission strategies between each of the second wireless access devices and the corresponding target terminal devices; Send the data transmission strategies to each of the second wireless access devices, so that each of the second wireless access devices can implement data transmission with the corresponding target terminal devices according to the data transmission strategies.

[0006] According to the cooperative transmission method provided by the present application, the determination that itself is the wireless access device with the strongest cooperative transmission ability in the target cooperation set includes: Obtain the broadcast messages sent by each of the wireless access devices in the target cooperation set. The broadcast messages carry parameters representing the cooperative transmission ability; If the value of the parameter corresponding to the first wireless access device is the optimal value among the values of the parameters corresponding to each of the wireless access devices in the target cooperation set, determine that itself is the wireless access device with the strongest cooperative transmission ability in the target cooperation set.

[0007] According to the cooperative transmission method provided by the present application, the target cooperation set is determined in advance through the following steps: Determine each wireless access device within a preset range and the terminal devices connected to each of the wireless access devices; For each of the wireless access devices, determine the average value of the co-channel interference suffered by all terminal devices within its corresponding service range from other wireless access devices except itself; According to the average value of the co-channel interference, determine the co-channel interference graph corresponding to the preset range. In the co-channel interference graph, vertices represent wireless access devices, edges represent the existence of co-channel interference between wireless access devices, and the weight of an edge represents the degree of co-channel interference; Divide the wireless access devices within the preset range into multiple cooperation sets according to the weights of the edges in the co-channel interference graph, where the target cooperation set is any one of the multiple cooperation sets.

[0008] According to the cooperative transmission method provided by the present application, the determining the data transmission strategy between each of the second wireless access devices and the corresponding target terminal device according to the transmission requirement includes: Determine the cooperative transmission mode between each of the second wireless access devices and the corresponding target terminal device according to the transmission requirement, the cooperative transmission capabilities of each of the second wireless access devices, and the cooperative transmission capabilities of each of the target terminal devices; Determine the values of the transmission parameters required for each of the cooperative transmission modes; Determine the data transmission strategy between each of the second wireless access devices and the corresponding target terminal device according to the cooperative transmission mode and the values of the transmission parameters.

[0009] According to the cooperative transmission method provided by the present application, the determining the values of the transmission parameters required for each of the cooperative transmission modes includes: For each of the target terminal devices, determine the correlation relationship between the signal-to-interference-plus-noise ratio on the target resource unit set and the transmission parameters required for the corresponding cooperative transmission mode. The target resource unit set includes multiple resource units obtained by orthogonal frequency division multiple access technology, and the resource units are used to implement data transmission; According to the correlation relationship, determine the total amount of data transmitted by each of the target terminal devices on the target resource unit set; Taking the maximization of the total amount of data as the goal, obtain the optimal solution of the total amount of data, and obtain the values of the transmission parameters when the total amount of data obtains the optimal solution.

[0010] According to the cooperative transmission method provided by the present application, the broadcast message is encapsulated by a first frame structure. The first frame structure includes a very high throughput MAC layer capability information field. The reserved fields in the very high throughput MAC layer capability information field include an orthogonal frequency division multiple access mode support field and a spatial multiplexing mode support field. The orthogonal frequency division multiple access mode support field is used to identify whether the orthogonal frequency division multiple access mode is supported, and the spatial multiplexing mode support field is used to identify whether the cooperative spatial multiplexing mode is supported; The value of the parameter representing the cooperative transmission capability is: the value of the orthogonal frequency division multiple access mode support field in the broadcast message and the value of the spatial multiplexing mode support field.

[0011] According to the cooperative transmission method provided by the present application, the data transmission strategy includes the ID of the target terminal device, the cooperative transmission mode, and the values of the transmission parameters required for the cooperative transmission mode. The cooperative transmission modes include the orthogonal frequency division multiple access mode and the spatial multiplexing mode. The values of the transmission parameters required for the orthogonal frequency division multiple access mode include the value and location of the resource unit. The values of the transmission parameters required for the spatial multiplexing mode include the value of the transmission power and the transmission power limit value; The sending of the data transmission strategy to each of the second radio access devices includes: Encapsulating the data transmission strategy by a second frame structure and sending the information obtained after encapsulation to each of the second radio access devices; Wherein, the second frame structure includes a plurality of user information fields. The data transmission strategy between one second radio access device and a corresponding target terminal device corresponds to one user information field. The user information field includes an association identification field, a resource unit allocation field, a target receiving power field, a multi-radio access point cooperative transmission mode field, and a maximum transmission power field. The association identification field is used to uniquely identify the ID of a target terminal device. The multi-radio access point cooperative transmission mode field is used to identify the cooperative transmission mode used. The resource unit allocation field is used to represent the size and location of the resource unit. The target receiving power field is used to represent the value of the transmission power. The maximum transmission power field is used to represent the transmission power limit value.

[0012] The present application also provides a cooperative transmission device based on multiple wireless access devices, which is deployed on a first wireless access device in a target cooperation set. The target cooperation set includes multiple different wireless access devices, and the co-channel interference among the multiple wireless access devices is greater than a preset interference threshold. The first wireless access device is any one of the wireless access devices in the target cooperation set. The cooperative transmission device includes: a first sending module, configured to send a cooperative transmission request to the remaining wireless access devices in the target cooperation set if it is determined that itself is the wireless access device with the strongest cooperative transmission ability in the target cooperation set; a first determining module, configured to determine multiple second wireless access devices according to the messages returned by the remaining wireless access devices in response to the cooperative transmission request. The second wireless access devices are the wireless access devices in the target cooperation set that agree to participate in cooperative transmission; an obtaining module, configured to obtain the transmission requirements of each of the second wireless access devices and the target terminal devices involved in the transmission requirements. Each of the wireless access devices is connected to at least one terminal device, and the wireless access device is used to provide wireless local area network access services for the terminal device; a second determining module, configured to determine a data transmission strategy between each of the second wireless access devices and the corresponding target terminal device according to the transmission requirements; a second sending module, configured to send the data transmission strategy to each of the second wireless access devices, so that each of the second wireless access devices can implement data transmission with the corresponding target terminal device according to the data transmission strategy.

[0013] The present application also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, it implements the cooperative transmission method based on multiple wireless access devices as described in any one of the above.

[0014] The present application also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the cooperative transmission method based on multiple wireless access devices as described in any one of the above.

[0015] The present application also provides a computer program product, including a computer program. When the computer program is executed by a processor, it implements the cooperative transmission method based on multiple wireless access devices as described in any one of the above.

[0016] The present application provides a cooperative transmission method, apparatus, device and medium based on multiple wireless access devices. By dividing multiple wireless access devices with strong co-channel interference into a cooperative set (i.e., a target cooperative set), and determining the data transmission strategies of each wireless access device participating in cooperative transmission through the first wireless access device with the strongest cooperative transmission ability among them. Since the first wireless access device can comprehensively consider the transmission requirements to determine the optimal data transmission strategies between each of the second wireless access devices and the corresponding target terminal devices, the present application can solve the co-channel interference problem existing in multi-AP cooperative transmission in the scenario of dense AP deployment. At the same time, the present application does not need to introduce an access point controller, and can also avoid the situation of high network construction cost and high communication topology complexity existing in multi-AP cooperative transmission using a centralized WLAN network architecture. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 is a flowchart of a cooperative transmission method based on multiple wireless access devices shown in an embodiment of the present application; Figure 2 is a cooperative transmission scenario diagram of multiple wireless access devices shown in an embodiment of the present application; Figure 3 is a schematic diagram of a multi-AP cooperative uplink transmission process shown in an embodiment of the present application; Figure 4 is a schematic diagram of a multi-AP cooperative downlink transmission process shown in an embodiment of the present application; Figure 5 is a schematic diagram of the expansion result of the IE field in a Beacon frame shown in an embodiment of the present application; Figure 6 is a schematic diagram of the structure of a Multi-AP Trigger frame shown in an embodiment of the present application; Figure 7 is a format diagram of a Common Info field shown in an embodiment of the present application; Figure 8 is a format diagram of a User Info field shown in an embodiment of the present application; Figure 9 is a schematic diagram of the joint optimization principle shown in an embodiment of the present application; Figure 10It is a structural block diagram of a collaborative transmission device based on multiple wireless access devices shown in an embodiment of the present application; Figure 11 It is a schematic structural diagram of an electronic device shown in an embodiment of the present application. Detailed implementation manners

[0019] To make the objectives, technical solutions, and advantages of the present application clearer, the technical solutions in the present application will be clearly and completely described below with reference to the accompanying drawings in the present application. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

[0020] An overlapping basic service set refers to a phenomenon in a wireless local area network where the coverage ranges of two or more basic service sets (BSS) overlap. A basic service set refers to a network set composed of a single wireless access point and its associated terminal devices. In a wireless local area network, a channel is a channel for wireless network signal transmission. If multiple wireless access points are all set to communicate using the same channel, then their signals will be transmitted within the same frequency band, and these signals will be superimposed on each other, forming interference, and ultimately causing the receiver to be unable to correctly receive and process the signals. The main objective of most of the published 802.11 protocols is to improve the throughput of a single wireless access point and increase the number of user accesses. However, there is a lack of a collaborative relationship between wireless access points, and the purpose of collaborative management of multiple wireless access points is only to optimize channel selection or adjust the load between wireless access points. Although the newly released 802.11ax version has begun to focus on improving the user experience in high-density scenarios, the existing 802.11ax protocol is still difficult to completely solve the co-channel interference problem in dense deployment scenarios. And the centralized WLAN network architecture adopted in the related technologies, although this method can enable better cooperation between APs, when the number of APs is large, the access point controller needs to process a large amount of device interaction information. Secondly, the centralized WLAN network architecture requires each AP to be able to establish a communication connection with the access point controller, which not only increases the network construction cost but also increases the complexity of the communication topology.

[0021] To solve the problems in the related art, the present application provides a cooperative transmission method based on multiple wireless access devices. In this method, the multiple wireless access devices are wireless access points (APs), and the terminal devices are stations (STAs). The following will elaborate on this method. The method of the present application is applied to the first wireless access device in the target cooperation set. The target cooperation set includes multiple different wireless access devices, and the co-channel interference between the multiple wireless access devices is greater than a preset interference threshold. The first wireless access device is any one of the wireless access devices in the target cooperation set.

[0022] Figure 1 is a flowchart of a cooperative transmission method based on multiple wireless access devices shown in an embodiment of the present application. Referring to Figure 1 , the cooperative transmission method based on multiple wireless access devices of the present application includes the following steps: Step 101: If it is determined that itself is the wireless access device with the strongest cooperative transmission ability in the target cooperation set, send a cooperative transmission request to the remaining wireless access devices in the target cooperation set.

[0023] Before elaborating on step 101 in detail, the concept of the cooperation set of the present application will be described first. In this embodiment, each cooperation set (including the target cooperation set) is determined in advance through the following steps: Determine each wireless access device within a preset range and the terminal devices connected to each wireless access device; for each wireless access device, determine the average value of the co-channel interference suffered by all terminal devices within its corresponding service range from other wireless access devices except itself; according to the average value of the co-channel interference, determine the co-channel interference graph corresponding to the preset range. In the co-channel interference graph, the vertices represent wireless access devices, the edges represent the existence of co-channel interference between wireless access devices, and the weight of the edge represents the degree of co-channel interference; according to the weights of the edges in the co-channel interference graph, divide the wireless access devices within the preset range into multiple cooperation sets, where the target cooperation set is any one of the multiple cooperation sets. Among them, the preset range is any size range within the coverage of a wireless local area network, and the preset range can be set according to actual needs. For example, it can be the coverage of a wireless local area network on one floor, or the coverage of a wireless local area network in a building, or the coverage of a wireless local area network in a community.

[0024] The complete process of dividing into multiple cooperation sets is as follows: First, calculate the co-channel interference between each terminal device STA within the preset range and the wireless access device AP. Among them, the associated with any other co-channel interference can be expressed as: (1) Among them, represents the average transmission power, represents the channel gain between and represents the distance between and represents additive white Gaussian noise.

[0025] Next, calculate the average value of the co-channel interference received by all STAs within the service range from .

[0026] (2) Among them, represents the number of all STAs within the service range, that is, the number of all STAs connected (associated) to , represents the total value of the co-channel interference received by all STAs within the service range from .

[0027] Next, introduce the AP interference matrix : (3) Among them, represents the average value of the co-channel interference received by all STAs within the service range from , is the AP interference threshold. Next, based on the interference matrix , establish the co-channel interference graph . In the co-channel interference graph, each vertex in the vertex set represents an AP, and each edge in the set represents the existence of co-channel interference between APs. represents and there is co-channel interference greater than the interference threshold between, at this time, set the weight of the edge between and in the co-channel interference graph to . represents and there is no co-channel interference between, at this time, in the co-channel interference graph between and​ The weight of the edge between and is set to be much greater than the maximum value of the edge lengths in the interference graph G. Then, according to the weights of the edges in the co-channel interference graph , the APs with a relatively high degree of interference with each other are grouped into the same cluster (hereinafter denoted as ), that is, the vertices with relatively short distances in the interference graph are grouped into the same cluster. The clustering algorithm adopted in this application can be determined according to actual requirements. For example, it can be at least any one of K-Means Clustering, Hierarchical Clustering, and DBSCAN (Density-Based Spatial Clustering of Applications with Noise).

[0028] In this application, a cluster represents a collaborative set. To control the number of APs in a single collaborative set, a is defined for each collaborative set: (4) where represents the sum of the weights of the edges between any two different vertices in a collaborative set, represents the co-channel interference graph in and the weight of the edge between. Each collaborative set needs to satisfy , represents the interference upper limit value corresponding to each collaborative set. Therefore, by reasonably setting , the number of APs in each collaborative set can be restricted, and thus the scale of the AP collaborative set can be controlled.

[0029] Before step 101, the method of this application may further include: obtaining the broadcast messages sent by each wireless access device in the target collaborative set, where the broadcast messages carry parameters characterizing the co-transmission ability; if the value of the parameter corresponding to the first wireless access device is the optimal value among the values of the parameters corresponding to each wireless access device in the target collaborative set, determining itself as the wireless access device with the strongest co-transmission ability in the target collaborative set.

[0030] In this embodiment, during the multi-AP collaborative transmission process, an AP is defined as two roles: Sharing AP and Shared AP. A Sharing AP refers to an AP that successfully obtains a transmission opportunity and has the intention to initiate multi-AP collaborative transmission. That is, a Sharing AP is not only the initiator of collaborative transmission in the collaborative set, but also responsible for formulating the data transmission strategy in collaborative transmission. A Shared AP refers to an AP that participates in the collaborative transmission initiated by the sharing AP. The Shared AP transmits according to the resource unit (RU) and / or transmission power indicated by the sharing AP, and receives collaborative scheduling from the Sharing AP to ensure that co-channel interference can be effectively reduced during the collaborative transmission process.

[0031] In the multi-AP collaborative information interaction, each AP in the target collaborative set will announce its collaborative transmission ability to other surrounding APs by broadcasting beacon frames. The Capability Information field in the beacon frame will be extended, and descriptive fields will be added to indicate the collaborative transmission ability of the AP. Exemplarily, AP1 adds fields indicating support for Coordinated Orthogonal Frequency Division Multiple Access (C-OFDMA) and Collaborative Spatial Reuse (CSR) in the broadcast beacon frame. Surrounding APs such as AP2 and AP3 can understand the collaborative transmission ability of AP1 by parsing these fields. Therefore, through the above method, each AP in the target collaborative set can determine its own and other APs' collaborative transmission abilities. In this embodiment, the parameters characterizing the collaborative transmission ability at least include the parameter indicating the support ability for C-OFDMA of collaborative orthogonal frequency division multiple access, and the parameter indicating the support ability for CSR of collaborative spatial reuse.

[0032] In this application, the Sharing AP is referred to as the first wireless access device. There is only one Sharing AP in a collaborative set. When an AP becomes a Sharing AP, it will send a Multi-AP Announcement frame to other APs in the collaborative set, that is, initiate a collaborative transmission announcement (i.e., a collaborative transmission request). As a preparation stage before the actual collaborative transmission, this collaborative transmission announcement can ensure effective information exchange between APs. Exemplarily, after AP1 successfully becomes a Sharing AP, it sends Multi-AP Announcement frames to AP2, AP3, etc. respectively, announcing that collaborative transmission is about to start.

[0033] Step 102: Determine multiple second wireless access devices according to the messages returned by the remaining wireless access devices in response to the cooperative transmission request. The second wireless access devices are the wireless access devices in the target cooperative set that agree to participate in the cooperative transmission.

[0034] In this embodiment, the AP that receives the cooperative transmission request will send a Multi-AP Response frame as a response message for feedback to indicate whether it agrees to participate in this cooperative transmission. The response message includes information about the STAs associated with this AP, the setting of the transmission power, and the RU allocation, etc. For example, after receiving the cooperative transmission request from AP1, AP2 and AP3 respectively send Multi-AP Response frames containing information about their respective associated STAs, transmission power, and RU allocation to AP1. Therefore, in this embodiment, the first wireless access device can determine which APs agree to participate in this cooperative transmission according to the received Multi-AP Response frames from each AP.

[0035] In this embodiment, each AP in the entire target cooperative set that agrees to participate in the cooperative transmission is referred to as a second wireless access device. The second wireless access devices may or may not include the first wireless access device.

[0036] Step 103: Obtain the transmission requirements of each second wireless access device and the target terminal devices involved in the transmission requirements. Each wireless access device is respectively connected to at least one terminal device, and the wireless access device is used to provide wireless local area network access services for the terminal devices.

[0037] In this embodiment, if there is a transmission requirement between a certain AP and a certain STA, then this AP will write the transmission requirement into the Multi-AP Response frame. In this way, the first wireless access device can determine the transmission requirements of each second wireless access device and the target terminal devices involved in the transmission requirements according to the received Multi-AP Response frames.

[0038] For example, the second wireless access devices include AP1 and AP2. AP1 is associated with STA1 and STA2, and AP1 is used to provide wireless local area network access services for STA1 and STA2. AP2 is associated with STA3 and STA4, and AP2 is used to provide wireless local area network access services for STA3 and STA4. If there is a transmission requirement between AP1 and STA1 and STA2, and there is a transmission requirement between AP2 and STA3, then the target terminal devices are STA1, STA2, and STA3.

[0039] Step 104: Determine the data transmission strategies between each second wireless access device and the corresponding target terminal device according to the transmission requirements. Among them, the transmission requirements may include the data type to be transmitted, the transmission time, the transmission protocol, etc. The content of the transmission requirements can be set according to actual needs.

[0040] In this embodiment, the first wireless access device comprehensively analyzes the transmission requirements of each second wireless access device, and determines the optimal data transmission strategies between each second wireless access device and the corresponding target terminal device, so as to minimize co-channel interference to the greatest extent.

[0041] Continuing from the previous embodiment, if there are transmission requirements between AP1 and STA1 and STA2, and there is a transmission requirement between AP2 and STA3, and AP1 is the first wireless access device, then AP1 will determine the data transmission strategies between AP1 and STA1, between AP1 and STA2, and between AP2 and STA3. Moreover, when determining each data transmission strategy, AP1 needs to ensure that when AP1 and STA1, AP1 and STA2, and AP2 and STA3 perform coordinated transmission using the corresponding data transmission strategies, co-channel interference is minimized to the greatest extent.

[0042] Step 105: Send the data transmission strategies to each second wireless access device, so that each second wireless access device can realize data transmission with the corresponding target terminal device according to the data transmission strategies.

[0043] In this embodiment, the first wireless access device can send the data transmission strategies in the form of a Multi-AP Trigger frame. The data transmission strategy used by each second wireless access device will be written in the Multi-AP Trigger frame, and the Multi-AP Trigger frames received by all second wireless access devices are the same.

[0044] In this embodiment, all the second wireless access devices are collectively referred to as Shared APs. The Sharing AP sends Multi-AP Trigger frames to all the Shared APs to trigger the official start of cooperative transmission. Each Shared AP parses the instructions in the Multi-AP Trigger frame to obtain the data transmission strategy it uses, and sets the transmission parameters accordingly, such as the cooperative transmission mode adopted, the size and location of the resource unit (RU), the value of the transmission power, the modulation and coding scheme (MCS), etc. By way of example, AP1 sends Multi-AP Trigger frames to AP2 and AP3, instructing them to start cooperative transmission. AP2 and AP3 set their respective transmission parameters according to the instructions in the Multi-AP Trigger frame and start data transmission with their respective STAs.

[0045] In this application, by dividing multiple wireless access devices with strong co-channel interference into a cooperative set (i.e., the target cooperative set), and determining the data transmission strategies of the respective second wireless access devices participating in cooperative transmission through the first wireless access device with the strongest cooperative transmission ability among them. Since the first wireless access device can comprehensively consider the transmission requirements to determine the optimal data transmission strategies between the respective second wireless access devices and the corresponding target terminal devices, this application can solve the co-channel interference problem existing in multi-AP cooperative transmission in the scenario of dense AP deployment. At the same time, this application does not need to introduce an access point controller and can also avoid the situation of high network construction cost and high communication topology complexity existing in multi-AP cooperative transmission using a centralized WLAN network architecture.

[0046] In this application, multi-AP cooperative transmission includes uplink cooperative transmission and downlink cooperative transmission. Next, the two cooperative transmission processes will be described separately. Figure 2 It is a cooperative transmission scenario diagram of multiple wireless access devices shown in an embodiment of this application. Figure 2 There are two BSSs, including BSS1 and BBS2. The target cooperative set includes AP1 and AP2. AP1 is associated with STA1 and STA2 to form BSS1, and AP2 is associated with STA3 to form BSS2.

[0047] Combined with Figure 2 , in one implementation, the key processes in multi-AP uplink cooperative transmission may include: Step 1: As the Sharing AP, AP1 first sends a Multi-AP Announcement frame to invite AP2 to participate in the cooperative transmission. The Multi-AP Announcement frame contains the basic information of the cooperative transmission, such as the transmission type (uplink cooperative transmission), transmission time, etc.

[0048] Step 2: After AP1 sends the Multi-AP Announcement frame, it waits for the feedback message from AP2. For example, if AP2 sends a feedback frame to AP1, after receiving the feedback frame, AP1 learns that STA3 has uplink data to be sent and needs to participate in this cooperative transmission. Therefore, AP1 adds STA3 to the cooperative transmission plan and prepares to generate a Multi-AP Trigger frame to trigger this uplink cooperative transmission.

[0049] Step 3: AP1 determines all STAs participating in this uplink cooperative transmission, including STA1, STA2, and STA3. AP1 determines the respective data transmission strategies of STA1, STA2, and STA3, and fills the User Info field corresponding to STA1 in the Multi-AP Trigger frame according to the data transmission strategy corresponding to STA1, fills the User Info field corresponding to STA2 in the Multi-AP Trigger frame according to the data transmission strategy corresponding to STA2, and fills the User Info field corresponding to STA3 in the Multi-AP Trigger frame according to the data transmission strategy corresponding to STA3, to obtain the final Multi-AP Trigger frame. For the data transmission strategy, if the cooperative transmission mode selects the C-OFDMA mode, AP1 will fill the RU Allocation field in the Multi-AP Trigger frame to specify the size and location of the resource unit RU used by each STA. If the cooperative transmission mode selects the C-SR mode, AP1 will fill the MAX TX power field and the UL Target Receive Power field to specify the maximum transmission power and the value of the target receive power (transmission power) of each STA respectively. AP1 sends the final Multi-AP Trigger frame to STA1, STA2, and STA3.

[0050] Step 4: AP2 receives and parses the Multi-AP Trigger frame, and detects that the User Info field of STA3 associated with itself is included therein, which indicates that STA3 is about to perform uplink data transmission. Therefore, AP2 will prepare to receive the uplink data transmission of STA3, such as adjusting the parameters of the receiver, allocating processing resources, etc. At the same time, STA1 and STA2 will also receive and parse the Multi-AP Trigger frame, and determine their own data transmission strategies according to the Common Info and User Info fields therein.

[0051] Step 5: After a Short Inter-Frame Space (SIFS), STA1 and STA2 respectively start to send uplink data to AP1 based on their corresponding data transmission strategies, and STA3 also starts to send uplink data to AP2 according to the indication of the Multi-AP Trigger frame. In the IEEE 802.11 wireless local area network protocol, the short inter-frame space represents the time required for a node to switch states and correctly decode, that is, the time required to switch from the transmission state to the reception state and be able to correctly decode, or the time required to switch from the reception state to the transmission state.

[0052] Step 6: AP1 sends BA (Block Acknowledgment) frames to STA1 and STA2 respectively to confirm that it has successfully received the data they sent. At the same time, AP2 sends a BA frame to STA3 to confirm that it has successfully received the data sent by STA3.

[0053] Figure 3 is a schematic diagram of a multi-AP collaborative uplink transmission process shown in an embodiment of the present application. In Figure 3 STA1, STA2, and STA3, after receiving the Multi-AP Trigger frame, after a short inter-frame space, STA1 uploads data to AP1 through RU1, STA2 uploads data to AP1 through RU2, and STA3 uploads data to AP2 through RU3.

[0054] Combined with Figure 2 In one embodiment, the key processes in multi-AP downlink collaborative transmission may include: Step 1: At a certain moment, AP1 determines through a certain mechanism (such as internal communication, protocol regulations, etc.) that AP2 has downlink data to send to STA3 associated with it.

[0055] Step 2: As a sharing AP, AP1 generates a Multi-AP Trigger frame that includes the User Info field of AP2. This frame is used to trigger multi-AP downlink cooperative transmission and indicate the data transmission strategies of each AP.

[0056] Step 3: After receiving the Multi-AP Trigger frame, AP2 parses the User Info field in it to find the information related to itself, including the cooperative transmission mode, resource unit RU (for example, when the cooperative transmission mode is the C-OFDMA mode, the RU it uses can be determined according to the RU Allocation field), and the information of the transmission power (for example, when the cooperative transmission mode is the C-SR mode, the maximum transmission power can be determined according to the MAX TX power, and the value of the transmission power can be determined according to the UL Target ReceivePower field).

[0057] Step 4: According to the indication in the Multi-AP Trigger frame, after a short inter-frame interval, AP2 sends downlink data to STA3. If the cooperative transmission mode is C-SR, AP2 will adjust its transmission power to ensure that it does not exceed the maximum transmission power indicated by the Max TXpower field. If the cooperative transmission mode is C-OFDMA, AP2 sends downlink data to STA3 according to the RU indicated in the RU Allocation field. At the same time, if STA1 and STA2 are also STAs participating in this downlink cooperative transmission, AP1 will also send downlink data to STA1 and STA2 according to the indication in the Multi-AP Trigger frame.

[0058] Figure 4 It is a schematic diagram of a multi-AP cooperative downlink transmission process shown in an embodiment of the present application. In Figure 4 After receiving the Multi-AP Trigger frame, after a short inter-frame interval, AP1 sends downlink data to STA1 through RU1 and sends downlink data to STA2 through RU2, and AP2 sends downlink data to STA3 through RU3 and RU4.

[0059] Combined with the above embodiments, in one implementation, the broadcast message is encapsulated through a first frame structure. The first frame structure includes a very high throughput MAC layer capability information field. The reserved fields in the very high throughput MAC layer capability information field include an orthogonal frequency division multiple access mode support field and a spatial multiplexing mode support field. The orthogonal frequency division multiple access mode support field is used to identify whether the orthogonal frequency division multiple access mode is supported, and the spatial multiplexing mode support field is used to identify whether the cooperative spatial multiplexing mode is supported; The value of the parameter characterizing the co - transmission ability is: the value of the orthogonal frequency - division multiple access mode support field and the value of the spatial multiplexing mode support field in the broadcast message. Among them, the first frame structure is the Beacon frame structure.

[0060] In this embodiment, each AP periodically sends out a broadcast message representing its own co - transmission ability at a preset time interval. This application uses the improved Beacon frame structure to generate the broadcast message. The basic structure of the Beacon frame includes fields such as 802.11 MAC Header, Frame Control field, Duration, Destination MAC address, Source MAC address, Basic Service Set Identifier (BSSID), etc. To meet the requirements of the 802.11be standard for extremely high throughput (EHT), this application extends the fields of the Beacon frame to include more information about the co - transmission ability, which can be specifically achieved by adding an Information Element (IE) field. The 802.11be protocol designates Element ID = 255 as the EHT Capabilities field, which is used for the definition of the high - throughput capabilities of MAC - layer APs and STAs and supports further expansion.

[0061] Figure 5 It is a schematic diagram of the IE field expansion result in a Beacon frame shown in an embodiment of this application. Figure 5 shows the frame structure of the EHT Capabilities field in the 802.11be protocol. Among them, Element ID (1 byte): used to identify the type of information element; Length (1 byte): represents the length of the entire information element; Element ID Extension (1 byte): represents the extension field, used to identify more specific sub - element types; EHT MAC Capabilities Information (2 bytes): represents MAC - layer capability information, used to define the high - throughput capabilities of devices in the EHT environment; EHT PHY Capabilities Information (9 bytes): represents physical - layer capability information; Supported EHT - MCS And NSS Set (variable length): represents the modulation and coding schemes (MCS) and the number of spatial streams (NSS) supported by the device; EHT PPE Thresholds (optional): used for PPE (Preamble Puncturing and Enhancement) threshold configuration. In Figure 5In it, octets are a combination of eight binary digits (bits), also known as a byte.

[0062] Furthermore, the EHT MAC Capabilities Information field consists of multiple sub-fields, and each sub-field defines the capabilities of the device in the EHT environment in units of bits. EPCS Priority Access Support (1 bit): Indicates whether the enhanced priority access control mechanism is supported; EHT Link Adaptation Support (2 bits): Used for link adaptation mechanism support, indicating the degree of support of the device for link adjustment capabilities; Reserved (2 bits): Reserved field, which can be used for future expansion.

[0063] For the Reserved field in the EHT MAC Capabilities Information field, the C-OFDMA Mode Support field and the C-SR Mode Support field can be further expanded to support the multi-AP cooperative transmission mode. Among them, C-OFDMA Mode Support (1 bit): Used to identify whether the device supports the cooperative orthogonal frequency division multiple access (C-OFDMA) mode; C-SR Mode Support (1 bit): Used to identify whether the device supports the cooperative spatial multiplexing (C-SR) mode.

[0064] Combined with the above embodiments, in one implementation, the data transmission strategy includes the ID of the target terminal device, the cooperative transmission mode, and the values of the transmission parameters required for the cooperative transmission mode. The cooperative transmission mode includes the orthogonal frequency division multiple access mode and the spatial multiplexing mode. The values of the transmission parameters required for the orthogonal frequency division multiple access mode include the value and location of the resource unit. The values of the transmission parameters required for the spatial multiplexing mode include the value of the transmission power and the transmission power limit value; Correspondingly, sending the data transmission strategy to each second wireless access device may include: encapsulating the data transmission strategy through the second frame structure and sending the obtained information after encapsulation to each second wireless access device.

[0065] The second frame structure includes multiple user information fields, a data transmission strategy between a second wireless access device and a corresponding target terminal device corresponds to a user information field, and the user information field includes an association identification field, a resource unit allocation field, a target receiving power field, a multi-radio access point cooperative transmission mode field, and a maximum transmission power field. The association identification field is used to uniquely identify an ID of a target terminal device, the multi-radio access point cooperative transmission mode field is used to identify the cooperative transmission mode used, the resource unit allocation field is used to indicate the size and position of the resource unit, the target receiving power field is used to indicate the value of the transmission power, and the maximum transmission power field is used to indicate the transmission power limit value. The second frame structure is the Multi-AP Trigger frame structure.

[0066] The present application also improves the structure of the Multi-AP Trigger frame. Figure 6 1 is a schematic diagram of the structure of a Multi-AP Trigger frame shown in an embodiment of the present application. Figure 6 As shown, the Multi-AP Trigger frame of this application adopts the basic trigger frame format in the IEEE 802.11ax protocol (802.11be is inherited from 802.11ax). In order to support multi-AP cooperative transmission, it is necessary to extend the Common Info field and the User Info field. The Common Info field is mainly used to carry the common information required by multiple STAs in the uplink transmission; the User Info field is used to indicate the data transmission strategy assigned by the AP to each STA, such as cooperative transmission mode, available RU, transmission power, MCS information, etc.

[0067] exist Figure 6 In the , Frame Control (2 bytes): used to describe the frame type and subtype, protocol version and control flag, indicating that the frame is a trigger frame, distinguishing management frames, control frames or data frames; Duration (2 bytes): used to specify the duration required for the entire frame exchange, ensuring that all STAs complete the transmission within the specified time window to avoid conflicts; RA (Receiver Address, 6 bytes): indicates the receiver address, usually the target STA or AP MAC address of the trigger frame, indicating which receiving device the trigger frame is for; TA (Transmitter Address, 6 bytes): indicates the sender address, that is, the MAC address of the AP that initiates the trigger frame, used to identify the AP that triggers the transmission; Padding (variable length): ensures that the frame length meets the standard, maintains data alignment, and avoids parsing errors; FCS (Frame Check Sequence, 4 bytes): provides a cyclic redundancy check (CRC) to ensure that the frame is not damaged during transmission.

[0068] Figure 7 This is a format diagram of a Common Info field shown in an embodiment of the present application. In Figure 7Among them, TriggerType (4 bits): It is used to indicate the type and subtype of the trigger frame, and its value range is 8 - 15 (reserved values). In 802.11ax, 8 - 15 are reserved bits, while in 802.11be, these bits are redefined for Multi-AP Trigger frames to identify different trigger subtypes. For example: 0001 - Basic trigger frame, 1000 - Multi-AP Trigger frame (for multi-AP coordination). ULLength (12 bits): It represents the duration of the uplink (UL) transmission, ensuring that the STA completes the transmission within the correct time window. The unit is symbol period, and its value range is 0 - 4095. Multi-AP Label (1 bit): It is used to indicate whether the multi-AP coordinated transmission mode is enabled. When its value is 0, it means that the multi-AP coordinated transmission is turned off, and only a single AP manages this trigger frame. When its value is 1, it means that the multi-AP coordinated transmission is turned on, and the AP and STA participate in the coordinated transmission mode. CS required (1 bit): It is used to indicate whether the STA needs to perform carrier sense before uplink transmission. When its value is 0, it means that no carrier sense is required and it directly responds to the trigger frame. When its value is 1, it means that carrier sense is required to avoid collision transmission. UL BW (2 bits): It is used to specify the bandwidth allocation of the uplink. When its value is 00, it means the bandwidth is 20 MHz. When its value is 01, it means the bandwidth is 40 MHz. When its value is 10, it means the bandwidth is 80 MHz. When its value is 11, it means the bandwidth is 160 MHz or higher. GI and HE-LTF type / triggered Multi-AP sharing mode (2 bits): It is used to indicate the guard interval (GI) and the HE-LTF (High-Efficiency Long Training Field) type, showing how multi-APs share LTF resources. The meaning of its values: 00 - 0.8μs GI, HE-LTF single symbol; 01 - 1.6μs GI, HE-LTF two symbols; 10 - 3.2μs GI, HE-LTF three symbols; 11 - Multi-AP sharing mode. MU-MIMO HE-LTF Mode (1 bit): It is used to indicate whether HE-LTF in the multi-user MIMO (MU-MIMO) mode is enabled. The meaning of its values: 0 - Disable MU-MIMO; 1 - Enable MU-MIMO. Number of HE / EHT-LTF symbols (3 bits): It is used to specify the number of HE or EHT-LTF symbols used to further optimize the reliability of multi-STA transmission. Its value range: 000 - 1 symbol; 111 - 8 symbols.

[0069] Figure 8 This is a format diagram of a User Info field shown in an embodiment of the present application. In this embodiment, when the sharing AP allocates resources to multiple STAs, multiple User Info fields (i.e., user information fields) need to be included in the Multi-AP Trigger frame. As Figure 8 shown, the AID12 field (i.e., the association identifier field) is used to identify a specific STA associated with the AP, and this identifier is divided within the scope of a cooperative set rather than a single BSS. The User Info field can include Trigger dependent User Info sub-fields of different lengths according to the extended type of the Multi-AP Trigger frame, which are used to carry additional information. In the Trigger dependent User Info field, there is a 3-bit Multi-AP Mode sub-field (i.e., the multi-AP cooperative transmission mode field) and a variable-length Max TX power sub-field (i.e., the maximum transmission power field), where the Max TX power is an optional field and is used to set the transmission power threshold (the maximum transmission power value) in the C-SR mode. The Multi-AP Mode is used to indicate the cooperative transmission mode used in this multi-AP cooperative transmission, and the field coding table is shown in Table 1:

[0070] Table 1 The following introduces in detail Figure 8Format of the User Info field shown: AID12 (12 bits) / Association Identifier field: The Association Identifier (AID) of the STA, which is used to distinguish different STAs. AID12 is extended to the entire coordination set, not limited to the basic service set (BSS) of a single AP. Its value range is 0 - 4095, and each STA is uniquely identified within the coordinated AP set by AID12 to avoid conflicts between STAs within the same frame. RU Allocation (8 bits) / Resource Unit Allocation field: The size and location of the resource units (RUs) allocated to the STA. RU represents the division unit of the spectrum resource, and each STA can be allocated RUs of different sizes to meet different transmission requirements. UL FFC Coding Type (1 bit): Indicates whether to use the Low-Density Parity-Check (LDPC) coding method. The meaning of its value: 0 - BCC (Convolutional Coding); 1 - LDPC coding, which improves transmission reliability and rate. UL MCS (4 bits): Specifies the modulation and coding scheme (MCS) of the STA. Its value range: 0 - 15, representing different combinations of modulation orders and coding rates. UL DCM (1 bit): Indicates whether to adopt dual-carrier modulation to reduce the requirements for the transmission quality of the STA. SS Allocation / RA-RU Information (3 bits): Used to allocate the number of spatial streams (SSs) to the STA. Its range: 1 - 8 streams, depending on the number of antennas of the STA and the spatial multiplexing ability of the AP. UL Target Received Power (7 bits) / Target Received Power field: Used to set the signal power that the AP expects to receive when the STA sends data, that is, the transmission power, which facilitates the coordinated reception power management among multiple APs to avoid interference. Reserved (1 bit): Reserved bit, which is used to reserve space for future protocol extensions or function additions. Multi-AP Mode (3 bits) / Multi-Access Point Coordinated Transmission Mode field: The multi-access point coordinated transmission mode field, which indicates the coordinated transmission mode used when multiple APs perform coordinated transmission. The field coding table is shown in Table 1. Max TX Power (variable length, optional field) / Maximum Transmission Power field: Used to indicate the maximum transmission power threshold allowed for the STA, usually set in the C-SR mode to avoid interference caused by excessive power. Unit: dBm. Range: 0 - 127 dBm (7-bit coding); 255 indicates no power limit.

[0071] In this application, in addition to improving the structures of Beacon frames and Multi-AP Trigger frames, the structures of Multi-AP Announcement frames and Multi-AP Response frames are also adaptively adjusted. Multi-AP Announcement frame: A control frame used for communication between multiple APs in a Wi-Fi network, including the User Info field of the shared AP, the cooperative transmission mode that the sharing AP hopes to execute, and information about the STAs participating in cooperative transmission in the basic service set of the sharing AP. Multi-AP Response frame: As a response frame to the Multi-AP Announcement frame, the Multi-AP Response frame contains the willingness of the shared AP to participate in multi-AP cooperative transmission, information about the STAs in the basic service set of the shared AP that support and participate in this cooperative transmission, the channel resources that the AP hopes to obtain, the size of the data to be transmitted, and data caching, etc.

[0072] The co-channel interference avoidance multi-AP cooperative radio resource allocation method provided in this application includes two parts: a co-channel interference avoidance mechanism for multi-AP cooperation and a radio channel resource allocation algorithm for interference avoidance. For the co-channel interference avoidance mechanism for multi-AP cooperation, APs with relatively large co-channel interference are divided into a cooperation set, and on this basis, a multi-AP cooperative information interaction method and a cooperative transmission process are designed. In addition, the relevant frame structures for multi-AP information interaction and cooperative triggering in the 802.11 protocol are improved and designed. The details of this part have been described in detail above. For the radio channel resource allocation algorithm for interference avoidance, the RU allocation problem and the power control problem are jointly optimized through an inner and outer double-loop method to maximize the throughput of the AP-dense deployment network. Next, the content about the radio channel resource allocation algorithm for interference avoidance will be explained.

[0073] In this application, according to the transmission requirements, determining the data transmission strategies between each second wireless access device and the corresponding target terminal device may include: determining the cooperative transmission mode between each second wireless access device and the corresponding target terminal device according to the transmission requirements, the cooperative transmission capabilities of each second wireless access device, and the cooperative transmission capabilities of each target terminal device; determining the values of the transmission parameters required for each cooperative transmission mode; and determining the data transmission strategies between each second wireless access device and the corresponding target terminal device according to the cooperative transmission mode and the values of the transmission parameters.

[0074] Specifically, determining the values of transmission parameters required for each cooperative transmission mode may include: for each target terminal device, determining the association relationship between the signal-to-interference-plus-noise ratio on the target resource unit set and the transmission parameters required for the corresponding cooperative transmission mode. The target resource unit set includes multiple resource units divided by orthogonal frequency division multiple access technology, and the resource units are used to implement data transmission; according to the association relationship, determining the total amount of data transmitted by each target terminal device on the target resource unit set; aiming at maximizing the total amount of data, obtaining the optimal solution of the total amount of data, and obtaining the values of the transmission parameters when the total amount of data obtains the optimal solution.

[0075] In this embodiment, if the transmission parameters required for the cooperative transmission mode involve RUs and transmission power, then during cooperative transmission, multiple STAs participating in the cooperative transmission transmit at a specific power on the RUs allocated by the associated AP. Therefore, the sharing AP needs to allocate RUs and transmission power to the STAs participating in the cooperative transmission according to the cooperative transmission mode specified in the Trigger frame.

[0076] The network is defined as follows: There are M APs, and N STAs, , where the subscript in is one of

[0077] One STA is only associated with one AP. The channel resources are divided according to the 802.11be OFDMA subcarrier RU standard, and the network available RUs are expressed as . Define the binary RU allocation vector : (5) Define the power allocation vector , indicating the transmission power p of STAn associated with APm on RU k. The signal-to-interference-and-noise ratio (SINR) transmitted on the RU set is expressed as: (6) Where represents 's received power, represents 's channel gain when transmitting on RU ; represents the co-channel interference received by n; represents Gaussian white noise.

[0078] Since the smaller the interference, the greater the effective throughput of the network, the interference avoidance problem can be converted into a joint optimization allocation problem of throughput maximization for RUs and power.

[0079] The throughput transmitted by the RUs in the RU set is calculated as: (7) where represents the bandwidth of RU k.

[0080] The total system throughput can be expressed as: (8) The resource allocation problem for throughput maximization is expressed as: (9) C1: (10) C2: (11) C3: (12) C4: (13) where C1 represents the uniqueness constraint of RU allocation. At the same time, an AP can only allocate each RU to one STA within its service range; C2 represents the transmission power limit of the STA; C3 represents the minimum transmission requirement of the signal-to-interference-plus-noise ratio (SINR) that the STA needs to meet during transmission; C4 represents that the total RU resources allocated to the STA cannot exceed the number of available RUs.

[0081] To reduce the computational complexity of the model constructed by solving formulas (9)-(13) and improve the computational efficiency, this application decomposes the problem into two sub-problems: RU allocation and power control, and uses an improved genetic algorithm and Q-learning algorithm to solve them respectively. At the same time, an inner and outer double-loop is used to achieve information interaction between the two algorithms. The RU allocation problem in the outer loop optimizes the channel allocation result through an improved genetic algorithm. Each individual in the population needs to obtain the feedback result of power control during each optimization process. The inner-loop power control adjusts the power level through the Q-learning algorithm and feeds the result back to the outer-loop RU allocation algorithm to achieve their joint optimization. The joint allocation algorithm for RUs and power is as Figure 9 shown. Figure 9 It is a schematic diagram of a joint optimization principle shown in an embodiment of this application.

[0082] (1)This application assigns RU as the outer loop, treats the power control feedback result as a fixed value, and optimizes channel allocation through an improved genetic algorithm. Next, steps such as the genetic algorithm encoding method, population initialization scheme, crossover and mutation operations, and individual selection are improved.

[0083] 1) Encoding method A chromosome encoding scheme representing the RU allocation status is designed using a binary encoding method. Suppose there are N STAs and K available RUs. The RU allocation status is represented by a chromosome The value of the nth gene ∈{0, 1} represents the allocation status of the nth RU. All chromosomes form an N×K encoding matrix X, representing the RU allocation situation of the wireless network after the I-th iteration.

[0084] (10) 2) Population initialization The population initialization adopts a method that combines random initialization with heuristic initialization based on power control feedback. The heuristic method based on power control feedback bundles adjacent RUs according to the RU aggregation (Multi-Resource Unit, MRU) technology proposed in 802.11be, and preferentially allocates larger RU resources to STAs with higher power. The population size is , The number of individuals is generated randomly, and the gene value is randomly taken as 0 or 1; The number of individuals is generated heuristically and satisfies .

[0085] 3) Fitness function The genetic algorithm receives the power control feedback result of Q learning and uses the objective function as the fitness function.

[0086] (11) 4) Crossover and mutation Crossover operation: To ensure that there are no duplicate genes after the chromosome undergoes the crossover operation, this application adopts the partially mapped crossover (PMX) strategy and the cycle crossover (CX) strategy for the crossover operation.

[0087] Mutation operation: The mutation operation of the improved genetic algorithm in this application adopts three mutation strategies: exchange-based mutation strategy, insertion-based mutation strategy, and MRU-based bit mutation strategy. The MRU-based mutation strategy combines the 802.11be MRU technology on the basis of the bit mutation strategy. The gene at position p changes to the same encoding as the gene at the adjacent position p - 1 or p + 1 with a certain probability to simulate the RU allocation method of RU aggregation.

[0088] After individuals undergo crossover and mutation operations with a certain probability, crossover and mutation offspring are generated. , and the genetic selection process for the next iteration is as follows: (12) Among them, represents a random value uniformly distributed between 0 and 1, and the crossover and mutation control factor depends on the current iteration number and the maximum iteration number, and is used to control the probability of replacing the reference individual with the crossover and mutation individual. The crossover and mutation factor will decrease with the increase of the iteration number, thereby increasing the survival probability of the mutated individuals and ensuring the global search ability and effective convergence of the algorithm.

[0089] 5)Correction operation Under the premise of meeting the interference constraint, this application needs to tolerate to a certain extent the overlapping RU allocation situation under different AP service ranges. After the chromosome crossover and mutation step, a chromosome correction judgment step is added. According to the value range of the network and spectrum, the genes that need to be corrected are randomly adjusted, and it is detected again whether the genes meet the requirements. The judgment conditions are as follows: 1) Each 26-tone RU cannot be simultaneously allocated to multiple STAs within the same AP range.

[0090] 2) When each 26-tone RU is simultaneously allocated to multiple STAs associated with different APs, calculate its interference degree. When the SINR of all STAs is greater than the threshold, the RU can be shared; otherwise, the genes of the STA with the highest power are preferentially corrected until the SINR of the remaining STAs is greater than the threshold or all do not meet the requirements.

[0091] 6)Individual selection Select the chromosome with the highest fitness according to the fitness function and copy it to the next generation, and then use the roulette wheel method to select the remaining K - 1 chromosomes.

[0092] The individual selection process needs to calculate the fitness function value of the hybrid individuals and the fitness function of the reference individuals , and select the individuals to be retained in the next generation population , which is expressed as: (13) The population is updated according to Equation (13). The individuals in each iteration are optimized through RU allocation. By continuously searching for the optimal solution in the population, the optimal individual in the population is selected as the optimal RU allocation result.

[0093] (2) Power control method based on Q-learning The Q-learning algorithm is used to generate a power control strategy based on the feedback result of RU allocation. The action space, state space, and reward function are defined according to the characteristics of the densely deployed WLAN.

[0094] 1) State space (S): The state space is the transmission power level allocated by the AP to the STA, and is defined as follows: (14) where the set element represents the transmission power level of STA n on RUk.

[0095] 2) Action space (A): The set representing all possible actions that the agent can take based on the state. The action space is defined as: ] (15) The set element are the three candidate actions that the agent can execute, namely: increasing the transmission power level, keeping the transmission power level unchanged, and decreasing the transmission power level.

[0096] 3) Reward function (R): Represents the expected reward obtained by the agent when executing an action. The system throughput in the t-th learning is defined as the reward. If the constraint conditions are not met, the penalty reward is 0.

[0097] (16) The Q-learning agent iteratively updates to achieve the power allocation of the AP to the STA through the process of action selection - state correction - Q-value update. The process is as follows: Step1: Initialize parameters and learning space: Initialize the search probability , discount factor and learning rate of the Q-learning algorithm. In the initial state, the transmission power is evenly distributed and the Q-value matrix is initialized. The state space and learning space are constructed according to Equations (14) and (15) respectively; Step2: Action selection: Use the interaction framework and message passing process inside the collaborative set mentioned above to obtain the current state , and select the action with the largest Q-value in the Q-value matrix for power adjustment based on the greedy action selection strategy with probability. With (1 - )Probabilistically select other actions for adjustment, and the action execution description is as follows: (17) (18) Among them, is the action execution result, is the selected action.

[0098] Step3: State correction: Obtain the action execution result , and determine whether there is a situation where the power level does not meet the limiting conditions C2 and C3 in formula (9). If not, correct the power level.

[0099] Step4: Reward function value and Q-value update: Update the state to according to the state correction result, and calculate and update the Q-value: (19) Among them, represents the Q-value at the t-th iteration in state and the selected action , is the learning rate, is the discount factor, represents the maximum Q-value in state , represents the reward.

[0100] Step5: Termination condition judgment: Judge whether the iteration termination condition is reached, that is, whether the maximum number of iterations is reached. If so, stop the iteration; otherwise, jump to Step2.

[0101] Obtain the optimized state in the Q-learning process as the optimized result of power control, and at the same time feedback the optimized result to the RU allocation algorithm as the input parameter for each iteration.

[0102] On the one hand, this application divides the interfering APs in the WLAN into multi-AP cooperation sets, performs cooperative transmission scheduling and radio resource allocation based on the cooperation sets as a unit, and designs a multi-AP cooperation information interaction method and a cooperative transmission process to support interference avoidance between APs and effective allocation of transmission resources. On the other hand, a radio channel resource allocation algorithm for interference avoidance is proposed: a RU and power allocation model aiming to maximize network throughput is constructed, and the improved genetic algorithm and Q-learning algorithm are respectively used to solve the RU allocation problem and the power control problem, and the joint optimization of the two is realized through the inner and outer double-loop feedback method. Through the solution of this application, the co-channel interference problem existing in multi-AP cooperative transmission in the scenario of dense AP deployment can be solved. At the same time, this application does not need to introduce an access point controller, and can also avoid the high network construction cost and high communication topology complexity existing in multi-AP cooperative transmission using a centralized WLAN network architecture.

[0103] The device provided by this application is described below. The cooperative transmission device based on multiple wireless access devices described below can be correspondingly referred to the cooperative transmission method based on multiple wireless access devices described above. The cooperative transmission device based on multiple wireless access devices provided by this application is deployed on the first wireless access device in the target cooperation set. The target cooperation set includes multiple different wireless access devices, and the co-channel interference between the multiple wireless access devices is greater than a preset interference threshold. The first wireless access device is any one of the wireless access devices in the target cooperation set.

[0104] Figure 10 It is a structural block diagram of a cooperative transmission device based on multiple wireless access devices shown in an embodiment of this application. Refer to Figure 10, the collaborative transmission device 1000 based on multiple wireless access devices of the present application may include: a first sending module 1001, configured to send a collaborative transmission request to the remaining wireless access devices in the target collaborative set if it is determined that itself is the wireless access device with the strongest collaborative transmission ability in the target collaborative set; a first determination module 1002, configured to determine a plurality of second wireless access devices according to the messages returned by the remaining wireless access devices in response to the collaborative transmission request, where the second wireless access devices are the wireless access devices in the target collaborative set that agree to participate in the collaborative transmission; an acquisition module 1003, configured to acquire the transmission requirements of each of the second wireless access devices and the target terminal devices involved in the transmission requirements, each of the wireless access devices is respectively connected to at least one terminal device, and the wireless access device is configured to provide a wireless local area network access service for the terminal device; a second determination module 1004, configured to determine a data transmission strategy between each of the second wireless access devices and the corresponding target terminal device according to the transmission requirements; a second sending module 1005, configured to send the data transmission strategy to each of the second wireless access devices, so that each of the second wireless access devices realizes data transmission with the corresponding target terminal device according to the data transmission strategy.

[0105] According to a collaborative transmission device 1000 based on multiple wireless access devices provided by the present application, the first sending module 1001 includes: a first acquisition sub-module, configured to acquire the broadcast messages sent by each of the wireless access devices in the target collaborative set, where the broadcast messages carry parameters representing the collaborative transmission ability; a first determination sub-module, configured to determine that itself is the wireless access device with the strongest collaborative transmission ability in the target collaborative set if the value of the parameter corresponding to the first wireless access device is the optimal value among the values of the parameters corresponding to each of the wireless access devices in the target collaborative set.

[0106] According to a collaborative transmission device 1000 based on multiple wireless access devices provided by the present application, the target collaborative set is determined in advance through the following steps: Identify each wireless access device within a preset range and the terminal devices connected to each of the wireless access devices; for each of the wireless access devices, determine the average value of the co-channel interference suffered by all terminal devices within its corresponding service range from other wireless access devices except itself; based on the average value of the co-channel interference, determine the co-channel interference map corresponding to the preset range, in which vertices represent wireless access devices, edges represent the existence of co-channel interference between wireless access devices, and the weights of the edges represent the degree of co-channel interference; divide the wireless access devices within the preset range into multiple cooperation sets according to the weights of the edges in the co-channel interference map, where the target cooperation set is any one of the multiple cooperation sets.

[0107] According to a cooperative transmission device 1000 based on multiple wireless access devices provided by the present application, the second determination module 1004 includes: a second determination sub-module, configured to determine the cooperative transmission mode between each of the second wireless access devices and the corresponding target terminal device according to the transmission requirement, the cooperative transmission capabilities of each of the second wireless access devices, and the cooperative transmission capabilities of each of the target terminal devices; a third determination sub-module, configured to determine the values of the transmission parameters required for each of the cooperative transmission modes; a fourth determination sub-module, configured to determine the data transmission strategy between each of the second wireless access devices and the corresponding target terminal device according to the cooperative transmission mode and the values of the transmission parameters.

[0108] According to a cooperative transmission device 1000 based on multiple wireless access devices provided by the present application, the fourth determination sub-module includes: a fifth determination sub-module, configured to, for each of the target terminal devices, determine the correlation between the signal-to-interference-plus-noise ratio on the target resource unit set and the transmission parameters required for the corresponding cooperative transmission mode, where the target resource unit set includes multiple resource units obtained by orthogonal frequency division multiple access technology, and the resource units are used to implement data transmission; a sixth determination sub-module, configured to determine the total amount of data transmitted by each of the target terminal devices on the target resource unit set according to the correlation; a second acquisition sub-module, configured to take maximizing the total amount of data as the goal, obtain the optimal solution of the total amount of data, and acquire the values of the transmission parameters when the total amount of data obtains the optimal solution.

[0109] A collaborative transmission device 1000 based on multiple radio access devices provided by the present application, the broadcast message is encapsulated by a first frame structure, the first frame structure includes a very high throughput MAC layer capability information field, and the reserved fields in the very high throughput MAC layer capability information field include an orthogonal frequency division multiple access mode support field and a spatial multiplexing mode support field. The orthogonal frequency division multiple access mode support field is used to identify whether the orthogonal frequency division multiple access mode is supported, and the spatial multiplexing mode support field is used to identify whether the collaborative spatial multiplexing mode is supported; The value of the parameter characterizing the collaborative transmission capability is: the value of the orthogonal frequency division multiple access mode support field in the broadcast message and the value of the spatial multiplexing mode support field.

[0110] A collaborative transmission device 1000 based on multiple radio access devices provided by the present application, the data transmission strategy includes the ID of the target terminal device, the collaborative transmission mode, and the values of the transmission parameters required for the collaborative transmission mode. The collaborative transmission modes include the orthogonal frequency division multiple access mode and the spatial multiplexing mode. The values of the transmission parameters required for the orthogonal frequency division multiple access mode include the value and position of the resource unit. The values of the transmission parameters required for the spatial multiplexing mode include the value of the transmission power and the transmission power limit value; the second sending module 1005 includes: a sending sub-module, which is used to encapsulate the data transmission strategy through a second frame structure and send the information obtained after encapsulation to each of the second radio access devices; wherein, the second frame structure includes multiple user information fields. The data transmission strategy between one second radio access device and a corresponding target terminal device corresponds to one user information field. The user information field includes an association identification field, a resource unit allocation field, a target receiving power field, a multi-radio access point collaborative transmission mode field, and a maximum transmission power field. The association identification field is used to uniquely identify the ID of a target terminal device. The multi-radio access point collaborative transmission mode field is used to identify the used collaborative transmission mode. The resource unit allocation field is used to represent the size and position of the resource unit. The target receiving power field is used to represent the value of the transmission power. The maximum transmission power field is used to represent the transmission power limit value.

[0111] Figure 11 It is a schematic structural diagram of an electronic device shown in an embodiment of the present application. As Figure 11As shown, the electronic device may include: a processor 1110, a communications interface 1120, a memory 1130, and a communication bus 1140. Among them, the processor 1110, the communications interface 1120, and the memory 1130 complete communication with each other through the communication bus 1140. The processor 1110 may call the logical instructions in the memory 1130 to execute a cooperative transmission method based on multiple radio access devices. The method includes: if it is determined that itself is the radio access device with the strongest cooperative transmission ability in the target cooperative set, sending a cooperative transmission request to the remaining radio access devices in the target cooperative set; determining a plurality of second radio access devices according to the messages returned by the remaining radio access devices in response to the cooperative transmission request, where the second radio access devices are the radio access devices in the target cooperative set that agree to participate in the cooperative transmission; obtaining the transmission requirements of each of the second radio access devices and the target terminal devices involved in the transmission requirements, each of the radio access devices is respectively connected to at least one terminal device, and the radio access device is used to provide wireless local area network access services for the terminal device; determining a data transmission strategy between each of the second radio access devices and the corresponding target terminal device according to the transmission requirements; and sending the data transmission strategy to each of the second radio access devices, so that each of the second radio access devices can realize data transmission with the corresponding target terminal device according to the data transmission strategy.

[0112] In addition, when the logical instructions in the above-mentioned memory 1130 are implemented in the form of software function units and sold or used as an independent product, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0113] On the other hand, the present application also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the collaborative transmission method based on multiple radio access devices provided by the above-mentioned various methods. The method includes: if it is determined that itself is the radio access device with the strongest collaborative transmission ability in the target collaborative set, sending a collaborative transmission request to the remaining radio access devices in the target collaborative set; determining a plurality of second radio access devices according to the messages returned by the remaining radio access devices in response to the collaborative transmission request, where the second radio access devices are the radio access devices in the target collaborative set that agree to participate in the collaborative transmission; obtaining the transmission requirements of each of the second radio access devices and the target terminal devices involved in the transmission requirements, each of the radio access devices is connected to at least one terminal device, and the radio access device is used to provide wireless local area network access services for the terminal device; determining a data transmission strategy between each of the second radio access devices and the corresponding target terminal device according to the transmission requirements; sending the data transmission strategy to each of the second radio access devices, so that each of the second radio access devices can realize data transmission with the corresponding target terminal device according to the data transmission strategy.

[0114] In another aspect, the present application also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it realizes the collaborative transmission method based on multiple radio access devices provided by the above-mentioned various methods. The method includes: if it is determined that itself is the radio access device with the strongest collaborative transmission ability in the target collaborative set, sending a collaborative transmission request to the remaining radio access devices in the target collaborative set; determining a plurality of second radio access devices according to the messages returned by the remaining radio access devices in response to the collaborative transmission request, where the second radio access devices are the radio access devices in the target collaborative set that agree to participate in the collaborative transmission; obtaining the transmission requirements of each of the second radio access devices and the target terminal devices involved in the transmission requirements, each of the radio access devices is connected to at least one terminal device, and the radio access device is used to provide wireless local area network access services for the terminal device; determining a data transmission strategy between each of the second radio access devices and the corresponding target terminal device according to the transmission requirements; sending the data transmission strategy to each of the second radio access devices, so that each of the second radio access devices can realize data transmission with the corresponding target terminal device according to the data transmission strategy.

[0115] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the essence of the above technical solution, or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0116] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A cooperative transmission method based on multiple wireless access devices, characterized in that: A method for applying to a first wireless access device in a target collaborative set, wherein the target collaborative set includes multiple different wireless access devices, and co-channel interference between the multiple wireless access devices is greater than a preset interference threshold. The first wireless access device is any one of the wireless access devices in the target collaborative set, and the method includes: If it is determined that the wireless access device is the wireless access device with the strongest cooperative transmission capability in the target cooperative set, sending a cooperative transmission request to other wireless access devices in the target cooperative set; Determine, according to the message returned by the remaining wireless access devices in response to the coordinated transmission request, a plurality of second wireless access devices, where the second wireless access devices are wireless access devices in the target coordinated set that agree to participate in the coordinated transmission; Acquire transmission requirements of each of the second wireless access devices and target terminal devices involved in the transmission requirements, each of the wireless access devices is respectively connected to at least one terminal device, and the wireless access device is used to provide wireless local area network access services for the terminal devices; Determining, according to the transmission requirements, a data transmission strategy between each of the second wireless access devices and the corresponding target terminal device; The data transmission strategy is sent to each of the second wireless access devices, so that each of the second wireless access devices implements data transmission with the corresponding target terminal device according to the data transmission strategy.

2. The collaborative transmission method according to claim 1, characterized in that: The determining that the wireless access device itself is the wireless access device with the strongest cooperative transmission capability in the target cooperative set includes: Acquire a broadcast message sent externally by each of the wireless access devices in the target cooperative set, wherein the broadcast message carries a parameter representing a cooperative transmission capability; If the value of the parameter corresponding to the first wireless access device is the optimal value among the values ​​of the parameters corresponding to the wireless access devices in the target cooperative set, it is determined that the first wireless access device is the wireless access device with the strongest cooperative transmission capability in the target cooperative set.

3. The collaborative transmission method according to claim 1, characterized in that: The target coordination set is determined in advance through the following steps: Determine each wireless access device within a preset range and a terminal device connected to each of the wireless access devices; For each of the wireless access devices, determining an average value of co-channel interference of all terminal devices within the corresponding service range with other wireless access devices except the wireless access device itself; Determine, according to the average value of the co-channel interference, a co-channel interference graph corresponding to the preset range, wherein in the co-channel interference graph, vertices represent wireless access devices, edges represent the existence of co-channel interference between wireless access devices, and edge weights represent the degree of co-channel interference; According to the weights of the edges in the co-channel interference graph, the wireless access devices within the preset range are divided into a plurality of cooperation sets, wherein the target cooperation set is any one of the plurality of cooperation sets.

4. The collaborative transmission method according to claim 1, characterized in that: The determining, according to the transmission requirement, a data transmission strategy between each of the second wireless access devices and a corresponding target terminal device includes: Determining a collaborative transmission mode between each of the second wireless access devices and the corresponding target terminal device according to the transmission requirements, the collaborative transmission capabilities of each of the second wireless access devices, and the collaborative transmission capabilities of each of the target terminal devices; Determining the values ​​of transmission parameters required for each of the cooperative transmission modes; A data transmission strategy between each of the second wireless access devices and the corresponding target terminal device is determined according to the cooperative transmission mode and the value of the transmission parameter.

5. The collaborative transmission method according to claim 4, characterized in that: The determining the value of the transmission parameter required for each of the cooperative transmission modes includes: For each of the target terminal devices, determining an association between a signal to interference plus noise ratio on a target resource unit set and a transmission parameter required by a corresponding cooperative transmission mode, wherein the target resource unit set includes a plurality of resource units obtained by dividing the target resource unit using an orthogonal frequency division multiple access technology, and the resource units are used to implement data transmission; Determine, according to the association relationship, the sum of the data amounts transmitted by each of the target terminal devices on the target resource unit set; With the goal of maximizing the sum of the data amounts, an optimal solution for the sum of the data amounts is obtained, and the value of the transmission parameter when the sum of the data amounts obtains the optimal solution is obtained.

6. The collaborative transmission method according to claim 2, characterized in that: The broadcast message is obtained by encapsulating a first frame structure, wherein the first frame structure includes an extremely high throughput MAC layer capability information field, and a reserved field in the extremely high throughput MAC layer capability information field includes an orthogonal frequency division multiple access mode support field and a spatial multiplexing mode support field, wherein the orthogonal frequency division multiple access mode support field is used to identify whether an orthogonal frequency division multiple access mode is supported, and the spatial multiplexing mode support field is used to identify whether a collaborative spatial multiplexing mode is supported; The value of the parameter characterizing the cooperative transmission capability is: the value of the orthogonal frequency division multiple access mode support field and the value of the spatial multiplexing mode support field in the broadcast message.

7. The coordinated transmission method according to claim 4, characterized in that: The data transmission strategy includes the ID of the target terminal device, the cooperative transmission mode and the value of the transmission parameter required by the cooperative transmission mode, the cooperative transmission mode includes an orthogonal frequency division multiple access mode and a spatial multiplexing mode, the value of the transmission parameter required by the orthogonal frequency division multiple access mode includes the value and position of the resource unit, and the value of the transmission parameter required by the spatial multiplexing mode includes the value of the transmission power and the transmission power limit value; The sending the data transmission strategy to each of the second wireless access devices includes: Encapsulating the data transmission strategy through a second frame structure, and sending the encapsulated information to each of the second wireless access devices; The second frame structure includes multiple user information fields, a data transmission strategy between the second wireless access device and a corresponding target terminal device corresponds to one user information field, the user information field includes an association identification field, a resource unit allocation field, a target receiving power field, a multi-wireless access point cooperative transmission mode field and a maximum transmission power field, the association identification field is used to uniquely identify an ID of a target terminal device, the multi-wireless access point cooperative transmission mode field is used to identify the cooperative transmission mode used, the resource unit allocation field is used to indicate the size and position of the resource unit, the target receiving power field is used to indicate the value of the transmission power, and the maximum transmission power field is used to indicate the transmission power limit value.

8. A cooperative transmission device based on multiple wireless access devices, characterized in that: A first wireless access device deployed in a target collaborative set, the target collaborative set including a plurality of different wireless access devices, co-channel interference between the plurality of wireless access devices being greater than a preset interference threshold, and the first wireless access device being any one of the wireless access devices in the target collaborative set; The collaborative transmission device comprises: A first sending module, configured to send a coordinated transmission request to other wireless access devices in the target coordinated set if it is determined that the wireless access device has the strongest coordinated transmission capability in the target coordinated set; A first determination module, configured to determine a plurality of second wireless access devices according to messages returned by the remaining wireless access devices in response to the coordinated transmission request, wherein the second wireless access devices are wireless access devices in the target coordinated set that agree to participate in the coordinated transmission; An acquisition module, used to acquire the transmission requirements of each of the second wireless access devices and the target terminal device involved in the transmission requirements, each of the wireless access devices is respectively connected to at least one terminal device, and the wireless access device is used to provide wireless local area network access services for the terminal devices; A second determination module, configured to determine a data transmission strategy between each of the second wireless access devices and a corresponding target terminal device according to the transmission requirement; The second sending module is used to send the data transmission strategy to each of the second wireless access devices, so that each of the second wireless access devices can realize data transmission with the corresponding target terminal device according to the data transmission strategy.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the coordinated transmission method based on multiple wireless access devices as described in any one of claims 1 to 7 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the coordinated transmission method based on multiple wireless access devices as described in any one of claims 1 to 7 is implemented.

Images