Method for improving performance of wireless local area network and giving consideration to fairness of stations

Abstract

According to the method for improving the performance of the wireless local area network and giving consideration to the fairness of all the stations, a reconfigurable intelligent metasurface is used, the system performance of the wireless local area network is improved, and centralized control over the fairness of all the stations is taken into consideration; the method comprises the following steps of: 1) pre-designing a plurality of control codebooks according to a service range of a wireless local area network access point and a relative position of the access point and a reconfigurable intelligent metasurface; 2) scanning, using the same time period of the pre-designed control codebooks one by one, and counting the total throughput between the access point and each station during the use of each control codebook; 3) according to the information obtained in the scanning stage, considering the system performance of the wireless local area network and the fairness of each station, and calculating the probability Pi that each control codebook is used; 4) according to a preset periodic time frequency, selecting and using one control codebook in each time period according to the probability Pi; and 5) updating the probability Pi that the control codebook is used according to a preset updating frequency in order to adapt to the network requirement in time.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to a centralized control method that uses a reconfigurable intelligent metasurface to improve the performance of a wireless local area network system while taking into account the fairness of each site. Background Art

[0002] Wireless Local Area Network (WLAN) under the IEEE 802.11 wireless communication protocol standard has become the main solution for home wireless device access and network deployment in medium and large enterprises and commercial facilities. DCF (Distributed Coordination Function) is a media access control mechanism in the IEEE 802.11 wireless LAN standard, which is used to manage access between devices in a wireless network. DCF is a distributed protocol based on the carrier sense multiple access / collision avoidance (CSMA / CA) mechanism. It solves the multi-user communication problem through the binary back-off mechanism (BEB), reduces conflicts between nodes to a certain extent, and thus improves communication performance.

[0003] However, since the DCF mechanism is static for each device and does not take into account the congestion status of the network, conflicts may occur when the network is congested. During the continuous conflict and retransmission process, the contention window gradually increases, which will worsen the congestion and may eventually lead to transmission failure. Therefore, when multiple devices send at the same time, it will cause a collision, making it impossible for the receiving end to decode the transmitted frame. However, the physical layer may experience a capture effect, that is, when multiple frames arrive at the receiving end at different power levels, the frame with the strongest signal power can be demodulated. Therefore, even if there is synchronous transmission, as long as the signal power difference is large enough, a capture effect can be generated, so that the receiving end can still successfully receive some data.

[0004] Reconfigurable smart metasurfaces are usually composed of a large number of carefully designed electromagnetic units. By applying control signals to the adjustable elements on the electromagnetic units, the electromagnetic properties of these units can be dynamically controlled, thereby realizing active intelligent regulation of electromagnetic waves in space in a programmable manner, forming an electromagnetic field with controllable amplitude, phase, polarization and frequency. Therefore, reconfigurable smart metasurfaces have the ability to dynamically regulate the spatial energy distribution of wireless LAN signals in the environment, thereby improving the wireless LAN communication environment.

[0005] There are many existing devices that use the capture effect and reconfigurable smart metasurfaces to improve the performance of wireless LANs, but most of them have the following disadvantages: 1) they cannot guarantee fairness for sites with lower transmission power, resulting in poor user experience. 2) they often cannot adjust the power difference between sites in a timely manner according to the different loads of each site, and cannot adapt well to changes in network demand. Summary of the invention

[0006] The purpose of the present invention is to improve the performance of a wireless local area network system and take into account the fairness of each site in a scenario where multiple sites communicate with one access point at the same time.

[0007] Technical solution of the present invention: In order to achieve the above-mentioned purpose, the present invention proposes a method for improving the performance of wireless local area network while taking into account the fairness of each site, using a reconfigurable intelligent metasurface and utilizing the capture effect to improve the performance of the wireless local area network system while taking into account the fairness of each site. The centralized control method is suitable for scenarios where multiple sites communicate with one access point at the same time.

[0008] The centralized control method comprises the following steps:

[0009] In the first step, multiple control codebooks are pre-designed according to the service range of the wireless LAN access point and the relative position of the access point and the reconfigurable smart metasurface;

[0010] The control codebook is a fixed-length number composed of 0 and 1, which indicates the level of the control signal driving the reconfigurable smart metasurface unit; each number in the control codebook corresponds to each unit state: 0 indicates that the control signal of the corresponding unit is low, and 1 indicates that the control signal of the corresponding unit is high; the use of the control codebook described later means that the control board outputs the corresponding control signal to drive all units of the reconfigurable smart metasurface;

[0011] Using a pre-designed control codebook, channel fluctuations are caused between the signal transmission position and the signal reception position, and the signal strength of the beam in a specific direction of the wireless local area network is enhanced to produce a capture effect (that is, when multiple frames arrive at the receiving end at different power levels, the frame with the strongest signal power can be demodulated), reduce the probability of collision and improve performance; using the control codebook, the state of each unit on the reconfigurable smart metasurface can be dynamically adjusted, thereby realizing a variety of electromagnetic wave control functions;

[0012] The second step is to scan and use the same time period of the pre-designed control codebook one by one, and count the total throughput between the access point and each station during the use of each control codebook;

[0013] It should be noted that the present invention does not limit the duration of the above time period, which can be set according to actual network conditions.

[0014] The third step is to calculate the probability P of each control codebook being used based on the information obtained in the scanning phase, taking into account the performance of the wireless LAN system and the fairness of each site. i ; Using the following formula:

[0015]

[0016] Where n is the number of pre-designed control codebooks, P i is the probability that the i-th control codebook is used, called the activation probability, D i is the total throughput between the access point and each station during the use of the i-th control codebook in the second step, and w is the adjustment factor used to balance system performance and station fairness;

[0017] It should be understood that the larger the w value, the more it tends to fairness, and the smaller the w value, the more it tends to performance; in different network requirements, by continuously adjusting w, a trade-off can be made between performance and fairness; the above method enables each site to have a certain probability of obtaining power improvement.

[0018] The fourth step is to generate a pseudo-random number within a certain range for each time period according to the preset periodic time frequency;

[0019] Based on the pseudo-random number, the determined range of pseudo-random number generation, and the activation probability of each control codebook, a control codebook is selected for use in the following manner:

[0020] Calculate the cumulative probability:

[0021]

[0022] Among them C i is the cumulative probability, satisfying the following conditions: C0=0, C n =1,P j The activation probability of the jth control codebook;

[0023] Calculate and accumulate probability C i Associated X i value:

[0024] X i =X min +C i (X max -X min )(0≤i≤n)

[0025] Among them, X i is the cumulative probability C i The associated value; X min is the lower bound of pseudo-random numbers; C i is the cumulative probability mentioned above; X max is the upper bound of pseudo-random numbers;

[0026] It should be noted that the above cumulative probability and cumulative probability C i Associated X i The calculation of the value is performed immediately after updating the activation probability;

[0027] Finally, according to the generated pseudo-random numbers x and X i , determine the interval where x is located and select the corresponding control codebook;

[0028] Step 5: To meet network requirements in a timely manner, the activation probability of each control codebook is updated according to the preset update frequency; the following formula is used for calculation:

[0029]

[0030] Where n is the number of pre-designed control codebooks, P i is the activation probability of the i-th control codebook, D i is the total throughput between the access point and each station during the period when the i-th control codebook is used in the second step, and w is the adjustment factor used to balance system performance and station fairness;

[0031] It should be noted that the present invention is not limited to the preset time frequency, which can be set according to the actual network conditions; the present invention is not limited to the update frequency, which depends on the actual conditions and needs.

[0032] After completing the above steps, repeat steps 4 and 5.

[0033] It can be understood that by selecting a control codebook by a pseudo-random number, it is possible to avoid a certain control codebook from being used too frequently in a certain long period of time, and it is also possible to ensure that each control codebook has a chance to be used over a long period of time, and the activation probability of each control codebook can be adjusted according to the real-time network conditions, so that the selection of the control codebook is more flexible and dynamic.

[0034] Beneficial effects: The present invention first determines the control codebook according to the service range of the access point and the relative position of the access point and the reconfigurable intelligent metasurface; then the control codebooks are used one by one, and the total throughput between the access point and each site during the use of each control codebook is counted; then the activation probability of the control codebook is calculated according to the throughput; finally, the control codebook is randomly selected according to the activation probability of the control codebook, and the activation probability needs to be updated according to the preset update frequency. The present invention uses a reconfigurable intelligent metasurface to cause channel fluctuations between the access point and the site, enhance the signal strength in a specific direction, produce a capture effect, reduce the collision probability, improve the performance of the wireless local area network system and take into account the fairness of each site. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is the first application scenario of the present invention;

[0036] Figure 2 This is the second application scenario of the present invention;

[0037] Figure 3It is the structural block diagram of the control board;

[0038] Figure 4 It is a simple flow chart of a specific example of a centralized control scheme. DETAILED DESCRIPTION

[0039] The present invention proposes a centralized control method that uses a reconfigurable intelligent metasurface to improve the performance of a wireless local area network system while taking into account the fairness of each site.

[0040] In order to make the purpose, content and advantages of the present invention more clear, the present invention will be further described in detail with reference to the accompanying drawings and examples.

[0041] Figure 1 , Figure 2 There are two application scenarios, and the biggest difference between them is: Figure 1 In the scenario, the communication environment between the access point and the station is good, and data frame loss is almost only caused by collision; Figure 2 The communication environment between the access point and the site is poor, and even if there is no collision, many data frames will be lost. The systems in both scenarios are composed of a field programmable gate array (FPGA) as a control board, a reconfigurable smart metasurface, an access point, and multiple sites.

[0042] The control board contains a serial communication module, a pseudo-random number generation module, and a control codebook output module; the serial communication module receives information from the access point, which includes the activation probability of each control codebook; the pseudo-random number generation module generates a pseudo-random integer within a certain range of 1 to 255 at the beginning of each periodic time period, that is, every 0.1s; the control codebook output module selects a control codebook according to the pseudo-random number, the certain range, and the activation probability of each control codebook, and then according to the control codebook, the IO port of the control board outputs the corresponding high and low level control signals to drive the reconfigurable intelligent metasurface unit, thereby causing channel fluctuations between the signal transmission position and the signal reception position, increasing the signal in a specific direction, so that the stations in that direction obtain performance gains.

[0043] The reconfigurable intelligent metasurface used in this example is an electrically controlled reflective metasurface, which works at a central frequency of 2.4 GHz, a wireless communication frequency band, and can regulate the phase of electromagnetic waves in this frequency band. The reconfigurable intelligent metasurface in this example has a total of 12×12 units, each of which integrates two PIN diodes. The four level states of the two diodes, 00, 01, 11, and 10 (0 is a low level and 1 is a high level), correspond to the four phase states of the electromagnetic wave. Taking the phase corresponding to the level state 00 as the reference, the phase differences corresponding to the four level states are 0°, 90°, 180°, and 270°, respectively.

[0044] It should be noted that the reconfigurable intelligent metasurface used in this example has 12×12 units, that is, 12 rows and 12 columns, but the level states of the 12 units in each column are the same. Therefore, only a 24-bit control code book is required, and the 24 IO ports of the corresponding control board output corresponding control signals to drive all units of the reconfigurable intelligent metasurface to achieve regulation of electromagnetic waves.

[0045] The functions of the access point are: 1) Communicate with each site in the system and count the throughput between the access point and each site in real time; 2) Based on the throughput between the access point and each site, the access point takes into account the performance of the wireless LAN system and site fairness, calculates the activation probability of each control codebook, and sends it to the control board.

[0046] The role of a station is to communicate with an access point. In this example system, multiple stations send information to an access point at the same time, and multiple stations send fixed-size data packets and use a single and identical physical layer rate and the same transmission power, but the load will be different.

[0047] In order to improve the performance of the wireless LAN system and take into account the fairness of each site, a centralized control method is adopted. The specific steps are as follows:

[0048] In the first step, multiple control codebooks are pre-designed and stored in the control board according to the service range of the access point and the relative position of the access point and the reconfigurable smart metasurface.

[0049] In this example, the access point is on the same horizontal plane as the center of the reconfigurable smart metasurface and is located directly in front of the reconfigurable smart metasurface; according to the generalized Snell reflection law:

[0050]

[0051] Among them, θ r is the reflection angle, θ i is the incident angle, k0 is the wave vector in free space, n i is the refractive index of the medium, This is the phase gradient.

[0052]

[0053] Among them, λ is the wavelength of the electromagnetic wave, and f is the frequency of the electromagnetic wave.

[0054] The access point is the receiving end, so θ rThe angle of incidence is 0°, the frequency of the electromagnetic wave is 2.4 GHz, and different control codebooks are used according to the service range of the access point, so that the units between the columns of the reconfigurable intelligent metasurface produce a phase gradient, so that the electromagnetic wave in a specific incident angle direction is reflected by the reconfigurable intelligent metasurface to the access point, and the signal strength is enhanced, so that the station in a specific direction obtains performance gain.

[0055] This example designs four control codebooks, namely:

[0056] Control codebook 1, 101001010100000011111110, enhances the signal strength of electromagnetic waves in the direction of an incident angle of 10°, so that the station located at 10° in the direction of the reconfigurable smart metasurface obtains performance gain.

[0057] Control codebook 2, 100100111001001110010011, enhances the signal strength of electromagnetic waves in the direction of an incident angle of 30°, so that the station located at 30° in the direction of the reconfigurable smart metasurface obtains performance gain;

[0058] Control codebook 3: 010010011110011110001101, which enhances the signal strength of electromagnetic waves at an incident angle of 50°, so that the stations located at 50° on the reconfigurable smart metasurface obtain performance gains;

[0059] Control codebook 4: 010010001101111000100111, enhances the signal strength of electromagnetic waves at an incident angle of 60°, so that the station located at 60° in the reconfigurable smart metasurface obtains performance gain.

[0060] In the second step, the access point sends a scan start command to the control board. After receiving the command, the control board outputs corresponding control signals one by one according to the pre-stored control code book to drive all units of the reconfigurable intelligent metasurface for the same time period. In this example, the time period lasts for 1 second, and the total throughput between the access point and each station during the use of each control code book is counted.

[0061] It should be understood that the present invention does not limit the specific content of the scan start instruction and the duration of the above-mentioned time period.

[0062] In the third step, the access point uses the following formula to calculate the activation probability of each control codebook based on the throughput information obtained in the second step, taking into account the performance of the wireless LAN system and the fairness of the site:

[0063]

[0064] Where n is the number of pre-designed control codebooks, in this example n is 4, P iis the probability that the ith control codebook is applied to control the reconfigurable smart metasurface, called the activation probability, D i is the total throughput between the access point and each station during the use of the i-th control codebook in the second step, w is an adjustment factor used to balance system performance and station fairness. In this example, the value of w is 0.2.

[0065] It should be noted that the w value is not restricted and should be set according to actual conditions. The larger the w value, the more it tends to fairness, and the smaller the w value, the more it tends to performance. By continuously adjusting w, a trade-off can be made between performance and fairness.

[0066] Furthermore, the activation probability of each control codebook is sent to the control board through serial port communication.

[0067] In the fourth step, the control board generates a pseudo-random number within a certain range at a periodic time frequency, that is, every 0.1s. In this example, the pseudo-random number is generated using the LFSR (Linear Feedback Shift Register) algorithm. The pseudo-random number is an 8-bit binary number with a size range of 1 to 255, a starting value of 1, and the feedback polynomial is as follows:

[0068] x'=x 8 +x 7 +x 5 +x 4 +x 3 +1

[0069] Among them, x' is a newly generated pseudo-random number, and x is the pseudo-random number generated last time.

[0070] It should be noted that the present invention is not limited to the preset time frequency, and can be set according to actual network conditions.

[0071] Further, the control codebook output module selects to use a control codebook in the following manner according to the pseudo-random number, the determined range, and the activation probability of each control codebook:

[0072] Calculate the cumulative probability:

[0073]

[0074] Among them C i is the cumulative probability, satisfying the following conditions: C0=0, C n =1;P j The activation probability of the jth control codebook.

[0075] Calculate and accumulate probability C i Associated X i value:

[0076] X i =Xmin +C i (X max -X min )(0 ≤ i ≤ n)

[0077] Wherein, X i is the value associated with the cumulative probability C i ; X min is the lower bound of the pseudo-random number, which is 1 in this example; C i is the above-mentioned cumulative probability; X max is the upper bound of the pseudo-random number, which is 255 in this example;

[0078] It should be noted that the above-mentioned cumulative probability and the X i value associated with the cumulative probability C i are calculated immediately after updating the activation probability;

[0079] Finally, according to the generated pseudo-random number x and X i , determine the interval where x is located and select the corresponding control codebook.

[0080] It can be understood that the present invention generates a pseudo-random integer within the range of 1 to 255, and the above method divides the range of 1 to 255 into 4 intervals according to the activation probability of the control codebook, and selects the control codebook corresponding to the interval where the generated pseudo-random number is located.

[0081] For example, the activation probabilities of each control codebook are respectively: P1 = 0.3, P2 = 0.1, P3 = 0.3, P4 = 0.3;

[0082] It is calculated that C0 = 0, C1 = 0.3, C2 = 0.4, C3 = 0.7, C4 = 1;

[0083] It is further calculated that X0 = 1, X1 = 74.2, X2 = 98.6, X3 = 171.8, X4 = 255;

[0084] If X0 ≤ x ≤ X1, that is, x belongs to the interval [X0, X1], then select control codebook 1; if X1 < x ≤ X2, that is, x belongs to the interval (X1, X2], then select control codebook 2; if X2 < x ≤ X3, that is, x belongs to the interval (X2, X3], then select control codebook 3; if X3 < x ≤ X4, that is, x belongs to the interval (X3, X4], then select control codebook 4.

[0085] If the generated pseudo-random number x=171; then x belongs to the interval (X2,X3], then the control codebook 3 is selected to use, and the reconfigurable intelligent metasurface causes channel fluctuations, that is, the communication signal strength between the access point directly in front of it and the station located at 30° from it is enhanced; even if there are stations in multiple directions sending information frames to the access point at the same time, the information frame sent by the station located at 30° in the reconfigurable intelligent metasurface has the maximum power when it arrives at the access point, and the access point can correctly demodulate the information frame it sends, that is, a capture effect is generated, which reduces the probability of all information frames being lost due to collision.

[0086] Step 5: In order to adapt to network needs in a timely manner, the probability is updated every 5 seconds to update the activation probability of each control codebook using the following formula:

[0087]

[0088] Where n is the number of pre-designed control codebooks, in this example n is 4, P i is the activation probability of the i-th control codebook before updating, P' i is the activation probability of the i-th control codebook after update, D i is the total throughput between the access point and each station during the use of the i-th control codebook in the fourth step, w is the adjustment factor, and the value of w in this example is 0.2.

[0089] It should be noted that the present invention has no restriction on the updating frequency of the probability, and it can be set according to the actual network conditions.

[0090] You only need to repeat steps 4 and 5.

[0091] It can be understood that by selecting a control codebook by a pseudo-random number, it is possible to avoid a certain control codebook from being used too frequently in a certain long period of time, and it is also possible to ensure that each control codebook has a chance to be used over a long period of time, and the activation probability of each control codebook can be adjusted according to the real-time network status, so that the selection of the control codebook is more flexible and dynamic.

[0092] The example system described above only expresses one embodiment of the present invention, and its description is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, making several modifications and improvements without departing from the inventive concept all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the attached claims.

Claims

1. A method for improving wireless local area network performance while taking into account fairness of each station, characterized in that: A centralized control method is provided to improve the performance of a wireless local area network system and take into account the fairness of each site by using a reconfigurable intelligent metasurface. The centralized control method includes the following steps: In the first step, multiple control codebooks are pre-designed according to the service range of the wireless LAN access point and the relative position of the access point and the reconfigurable smart metasurface; The control codebook is a fixed-length number composed of 0 and 1, which indicates the level of the control signal driving the reconfigurable smart metasurface unit; each number in the control codebook corresponds to each unit state: 0 indicates that the control signal of the corresponding unit is low, and 1 indicates that the control signal of the corresponding unit is high; the use of the control codebook described later means that the control board outputs the corresponding control signal to drive all units of the reconfigurable smart metasurface; Using a pre-designed control codebook, channel fluctuations are caused between the signal transmission location and the signal reception location, enhancing the signal strength of the beam in a specific direction of the wireless LAN to produce a capture effect (i.e., when multiple frames arrive at the receiving end at different power levels, the frame with the strongest signal power can be demodulated), reducing the probability of collision and improving performance; The second step is to scan and use the same time period of the pre-designed control codebook one by one, and count the total throughput between the access point and each station during the use of each control codebook; The third step is to calculate the probability P of each control codebook being used based on the information obtained in the scanning phase, taking into account the performance of the wireless LAN system and the fairness of each site. i ; Using the following formula: Where n is the number of pre-designed control codebooks, P i is the probability that the i-th control codebook is used, called the activation probability, D i is the total throughput between the access point and each station during the use of the i-th control codebook in the second step, and w is the adjustment factor used to balance system performance and station fairness; It should be understood that the larger the w value, the more it tends to fairness, and the smaller the w value, the more it tends to performance; in different network requirements, by continuously adjusting w, a trade-off can be made between performance and fairness; the above method enables each site to have a certain probability of obtaining power improvement; The fourth step is to generate a pseudo-random number within a certain range for each time period according to the preset periodic time frequency; Based on the pseudo-random number, the determined range of pseudo-random number generation, and the activation probability of each control codebook, a control codebook is selected for use in the following manner: Calculate the cumulative probability: Among them C i is the cumulative probability, satisfying the following conditions: C0=0, C n =1,P j The activation probability of the jth control codebook; Calculate and accumulate probability C i Associated X i value: X i =X min +C i (X max -X min )(0≤i≤n) Among them, X i is the cumulative probability C i The associated value; X min is the lower bound of pseudo-random numbers; C i is the cumulative probability mentioned above; X max is the upper bound of pseudo-random numbers; It should be noted that the above cumulative probability and cumulative probability C i Associated X i The calculation of the value is performed immediately after updating the activation probability; Finally, according to the generated pseudo-random numbers x and X i , determine the interval where x is located and select the corresponding control codebook; Step 5: To meet network requirements in a timely manner, the activation probability of each control codebook is updated according to the preset update frequency; the following formula is used for calculation: Where n is the number of pre-designed control codebooks, P i is the activation probability of the i-th control codebook, D i is the total throughput between the access point and each station during the period when the i-th control codebook is used in the second step, and w is the adjustment factor used to balance system performance and station fairness; After completing the above steps, repeat steps 4 and 5.

2. The method for improving the performance of a wireless local area network while taking into account the fairness of each site according to claim 1, characterized in that: A control board is set up, which has a serial port module, a pseudo-random number generation module, and a control codebook output module; the serial port module receives information from the access point, which includes the activation probability of each control codebook; the pseudo-random number generation module generates a pseudo-random number within a determined range at the beginning of each periodic time period; the control codebook output module selects to use a control codebook according to the pseudo-random number, the determined range, and the activation probability of each control codebook, thereby causing channel fluctuations between the signal transmission position and the signal reception position, increasing the signal strength in a specific direction, so that the site in this direction obtains performance gain.

3. The method for improving the performance of a wireless local area network while taking into account the fairness of each site according to claim 1, characterized in that: Centralized control method, the specific steps are: In the first step, multiple control codebooks are pre-designed and stored in the control board according to the service range of the access point and the relative position of the access point and the reconfigurable smart metasurface; In the second step, the access point sends a scan start command to the control board. After receiving the command, the control board outputs the corresponding control signals one by one according to the pre-stored control codebook to drive all units of the reconfigurable intelligent metasurface for the same time period, and counts the total throughput between the access point and each station during the use of each control codebook; In the third step, the access point uses the following formula to calculate the activation probability of each control codebook based on the throughput information obtained in the second step, taking into account the performance of the wireless LAN system and the fairness of the site: Where n is the number of pre-designed control codebooks, P i is the activation probability of the i-th control codebook, D i is the total throughput between the access point and each station during the use of the i-th control codebook in the second step, and w is the adjustment factor used to balance system performance and station fairness; Further, the control codebook activation probability is sent to the control board; In the fourth step, the control board generates a pseudo-random number within a certain range for each time period according to the preset periodic time frequency.

4. The method for improving the performance of a wireless local area network while taking into account the fairness of each site according to claim 1, characterized in that: The output control codebook module selects a control codebook to use according to the pseudo-random number, the determined range, and the activation probability of each control codebook in the following manner: Calculate the cumulative probability: Among them C i is the cumulative probability, satisfying the following conditions: C0=0, C n =1;P j The activation probability of the jth control codebook; Calculate and accumulate probability C i Associated X i value: X i =X min +C i (X max -X min )(0≤i≤n) Among them, X i is the cumulative probability C i The associated value; X min is the lower bound of pseudo-random numbers; C i is the cumulative probability mentioned above; X max is the upper bound of pseudo-random numbers; It should be noted that the above cumulative probability and cumulative probability C i Associated X i The calculation of the value is performed immediately after updating the activation probability; Finally, according to the generated pseudo-random numbers x and X i , determine the interval where x is located and select the corresponding control codebook; In the fifth step, in order to adapt to network needs in a timely manner, the activation probability of each control codebook is updated according to the predetermined update frequency, using the following formula: Where n is the number of pre-designed control codebooks, P i is the activation probability of the i-th control codebook before updating, P' i is the activation probability of the i-th control codebook after update, D i is the total throughput between the access point and each station during the use of the i-th control codebook in the fourth step, and w is the adjustment factor; Repeat steps 4 and 5.

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