A frequency division based air interface load balancing method and device

Abstract

This application discloses an air interface load balancing method and device based on frequency allocation, belonging to the field of wireless local area network (WLAN) technology. The method includes: dynamically monitoring the number of access sites and downlink throughput, sorting all access sites according to their wireless transmission negotiation rate; triggering a frequency band allocation operation when the frequency band allocation conditions are met: creating two new basic service sets, dividing the current frequency band into two sub-bandwidths and allocating them to the two basic service sets respectively, migrating sites ranked higher to one basic service set, and sites ranked lower to the other; employing a single radio frequency (SRF) and time-division multiplexing (TDM) mechanism for data transmission and reception, wherein during data transmission and reception, the link status follows a mutually exclusive availability principle, and only one link is available at any given time, exclusively occupying all wireless and radio frequency resources. Dynamic frequency allocation and merging based on the number of users and user service status reduces the probability of air interface collisions between multiple users and optimizes air interface resource allocation.

Description

Technical Field

[0001] This application belongs to the field of wireless local area network technology, and specifically relates to an air interface load balancing method and device based on frequency division. Background Technology

[0002] Wi-Fi 6 utilizes Orthogonal Frequency Division Multiple Access (OFDMA) technology to divide the channel into resource units, supporting concurrent transmission by multiple devices and significantly improving network capacity and efficiency, making it particularly suitable for high-density scenarios. However, in practical applications, the following three factors affect the application of OFDMA: 1. There are still a large number of stations on the market that support Wi-Fi 4 and Wi-Fi 5 standards; 2. Only a portion of the data frames use OFDMA modulation, while a large number of management frames, control frames, and some data frames still use Orthogonal Frequency Division Multiplexing (OFDM) modulation. 3. Due to compatibility and complex environments, sometimes even if both the station and the access point (AP) communicate in accordance with the Wi-Fi 6 standard, they do not use the High-Efficiency Multi-User Physical Layer Protocol Data Unit (HEMUPPDU) frame format to transmit data, but instead use the High-Efficiency Single-User Physical Layer Protocol Data Unit (HESUPPDU) frame format.

[0003] Due to the above three factors and the Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA) mechanism, wireless air interface resources are not fully utilized under Wi-Fi's high bandwidth conditions. Summary of the Invention

[0004] To address the aforementioned issues, this invention proposes an air interface load balancing method and device based on frequency partitioning to optimize air interface resource allocation and improve air interface utilization.

[0005] This application provides an air interface load balancing method based on frequency band allocation, including: Dynamically monitor the number of access sites and downlink throughput, and sort all access sites according to the wireless transmission negotiation rate. When the frequency band allocation conditions are met, the frequency band allocation operation is triggered: two basic service sets are created, the current frequency band is divided into two sub-bandwidths and allocated to the two basic service sets respectively, and the sites ranked higher are migrated to one basic service set and the sites ranked lower are migrated to the other basic service set; the frequency band allocation conditions are: the number of access sites and the number of sites that meet the downlink throughput requirements both reach the corresponding preset thresholds and remain at the first preset duration, and one sub-bandwidth corresponds to one link; Data transmission and reception are performed using a single radio frequency and time-division multiplexing mechanism. During data transmission and reception, the link status follows the principle of mutual exclusion and availability, and only one link is available at any given time and exclusively occupies all radio and radio frequency resources.

[0006] Furthermore, the method also includes: The air interface resource allocation weight ratio of the two links is preset. When both links have radio frames to be transmitted at the same time and are both in an available state, or when the receiving tasks of the two links exist at the same time, it is determined that a task conflict has occurred. When a task conflict occurs, the corresponding target link is selected to perform the data transmission task or data reception task by combining the air interface resource allocation weight ratio and the link priority identifier.

[0007] Furthermore, the method also includes: When the number of access sites or the number of sites that meet the downlink throughput requirements falls below the corresponding preset threshold and remains below the threshold for a second preset duration, the two sub-bandwidths are merged and the system is restored to a single basic service set.

[0008] Furthermore, the two newly established basic service sets include: Create two new basic service sets while keeping the original service set identifier (SSID) unchanged.

[0009] Furthermore, the two links are the first link and the second link; Based on the air interface resource allocation weight ratio and link priority identifier, the appropriate target link is selected to perform the data transmission task, including: Check if there is a link whose link priority identifier is set to the first set value. If so, select the link directly and increment the transmission count of the link by 1 after each radio frame is transmitted. If no link exists, a random number is generated. If the generated random number is less than or equal to the weight ratio of the first link, the first link is selected to perform the data transmission task. Otherwise, the second link is selected to send the data, and the transmission count of the corresponding link is incremented by 1 after transmission.

[0010] Furthermore, the two links are the first link and the second link; During the channel sensing phase, when the first link and the second link simultaneously detect a radio frame to be received with the target address of this device, it is determined to be a receiving task conflict. Check if there is a link whose link priority identifier is set to the first value. If so, select the link to receive and increment the receive count of the link by 1 after each radio frame is received. If it does not exist, a random number is generated; if the random number is less than or equal to the weight ratio of the first link, the first link is selected for reception; otherwise, the second link is selected for reception, and the reception count of the corresponding link is incremented by 1 after reception. If the target address of a wireless frame is not detected to be this device, it will be discarded without further processing.

[0011] Furthermore, the method also includes: Set a timer to check the transmission count of the link once every first detection period. If the transmission count does not change, increment the starvation value of the link by 1. If the transmission count changes, decrement the starvation value by 1 until it reaches zero. If the hunger value corresponding to a link continues to increase for the third consecutive detection period, the priority flag of that link is set to the first preset value. After the second detection period, the priority flag is restored to the second preset value. The first detection period is shorter than the second detection period, and the second detection period is shorter than the third detection period.

[0012] Furthermore, data transmission and reception are performed using a single radio frequency and time-division multiplexing mechanism, including: A single radio frequency combined with time-division multiplexing mechanism is adopted. The two links are initially in the listening state. When the channel is detected to be idle, they enter the data transmission and reception state. A polling mechanism and a buffer queue are used for frame transmission.

[0013] This application also provides an air interface load balancing device based on frequency band division, which achieves air interface load balancing through the above-described air interface load balancing method based on frequency band division.

[0014] Furthermore, the air interface load balancing device is a wireless access point, a wireless router, or an ONU gateway.

[0015] Compared with the prior art, this application has the following advantages: By dynamically monitoring the number of access sites and throughput and introducing duration to determine the user's service status, frequent frequency band splitting and merging are avoided. By grouping sites in descending order of wireless transmission negotiation rate and mapping them to different sub-bandwidths, the drag of low-speed sites on high-speed sites is isolated, the number of WIFI management frames and control frames is reduced, and the utilization rate of the air interface is improved, which to some extent improves the overall air interface throughput in high-density and high-load scenarios. Under the single-radio time-division multiplexing architecture, single-link exclusivity is achieved through physical switching of all wireless and radio frequency resources, effectively aggregating transmit power to improve transmission reliability in narrowband time slots.

[0016] To address the inevitable dual-link transmit / receive conflicts in a single-RF architecture, a target link determination method combining preset weights, random number generation, and starvation compensation mechanisms is introduced. This enables refined allocation of air interface time resources, ensuring fairness and low latency in dual-link service scheduling.

[0017] Maintaining consistent SSIDs during frequency band allocation enables seamless and transparent migration of terminals, greatly reducing the risk of service interruption caused by terminal reconnection.

[0018] This application dynamically divides and merges frequencies based on the number of users and user service status. In multi-user high-concurrency service scenarios, the method of this application can enhance the WiFi anti-interference capability of the device, reduce the probability of air interface collisions between multiple users, optimize air interface resource allocation, thereby improving air interface utilization and enhancing user experience.

[0019] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A flowchart of an air interface load balancing method based on frequency division according to an embodiment of this application is shown; Figure 2 A schematic diagram of frequency band allocation according to an embodiment of this application is shown; Figure 3 The diagram illustrates the TX pattern of a wireless air interface collision scheduling algorithm according to an embodiment of this application. Figure 4 An air interface resource switching diagram according to an embodiment of this application is shown; Figure 5 The diagram illustrates the RX pattern of a wireless air interface collision scheduling algorithm according to an embodiment of this application. Detailed Implementation

[0022] This application provides a method for optimizing wireless air interface resource allocation. This method monitors the number of accessing STAs and traffic statistics for each site. All sites are sorted from highest to lowest according to their wireless transmission negotiation rate. Based on the number of accessing sites, downlink throughput, and duration, it determines whether frequency band allocation (e.g., equal allocation) and site migration are necessary. If so, the current frequency band is divided (e.g., evenly divided) into two sub-bandwidths corresponding to two links, and two new basic service sets (BSS1 and BSS2) are created. BSS1 and BSS2 maintain the same service set identifier (SSID) as the original. Sites ranked higher (e.g., the first half) are allocated to BSS1, and sites ranked lower (e.g., the second half) are allocated to BSS2. The two links are configured with an air interface resource allocation weight ratio. The AP uses a single-radio time-division multiplexing mechanism, and both links are initially in a listening state. When the channel is detected to be idle (i.e., available), the system enters the data transmission and reception state. A polling mechanism and buffer queue are used for frame transmission. Link status follows a mutually exclusive availability principle; only one link is available at any given time and exclusively occupies all radio and radio frequency resources. When both links have transmission needs, the corresponding link is selected to transmit data based on the link priority identifier and the air interface resource allocation weight ratio of the two links. When a radio frame to be received is detected during the channel sensing phase, all antennas and radio frequency resources are switched to the corresponding link. When two links have conflicting reception tasks, the corresponding link is selected to receive data based on the link priority identifier and the air interface resource allocation weight ratio of the two links. When the number of sites or downlink throughput does not meet the triggering conditions and remains below the second preset duration, a bandwidth reclamation mechanism is triggered: the two sub-bandwidths are merged, restoring the system to a single basic service set (BSS) working state.

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] like Figure 1 The diagram shown is a flowchart of an air interface load balancing method based on frequency division according to an embodiment of this application, which includes the following steps: Step 101: Dynamically monitor the number of sites connected to the current access point and the traffic statistics of each site; When the number of sites and traffic reach a certain threshold, it indicates that the air interface space is becoming congested and air interface optimization is needed.

[0025] Step 102: Determine whether the frequency band allocation conditions are met. If yes, proceed to step 103; otherwise, continue the detection in step 101 until the frequency band allocation conditions are met. The frequency band allocation conditions are as follows: the number of access sites and the number of sites that meet the downlink throughput requirements both reach the corresponding preset thresholds and remain so for a first preset duration.

[0026] Specifically, it can be: the downlink throughput of the access stations with a number of access stations greater than or equal to a first preset value and at least a second preset value is greater than or equal to a third preset value, and this state lasts for a first preset duration; The frequency segmentation conditions set in this embodiment are as follows: The number of access stations is greater than or equal to 32, and at least 16 stations have a downlink throughput greater than or equal to 1Mbps for a duration of 5 minutes.

[0027] Step 103: Divide the frequency band into two equal parts, and then proceed to step 104; The specific method for frequency band allocation is as follows: 1) Create two new basic service sets, BSS1 and BSS2. The ServiceSet Identifier (SSID), encryption authentication method, and password of BSS1 and BSS2 should be consistent with the SSID, encryption authentication method, and password of the previous single BSS.

[0028] 2) Divide the current bandwidth into two sub-bandwidths, denoted as B1 and B2 respectively. BSS1 uses B1, and BSS2 uses B2, as follows: Figure 2 As shown.

[0029] 3) Sort the wireless transmission (WiFi Tx) negotiation rates of all sites in descending order; 4) Trigger frequency band allocation.

[0030] Step 104: Perform station migration, then proceed to step 118; if there is a sending requirement, proceed to step 105; if there is a receiving requirement, proceed to step 112. Sites ranked in the top half will be migrated to BSS1, and sites ranked in the bottom half will be migrated to BSS2.

[0031] Step 105: Prepare to send a wireless frame; Specifically, a polling mechanism is used to send wireless frames, and two links and their corresponding buffer queues are configured: sending queue 1 corresponds to link 1, and sending queue 2 corresponds to link 2.

[0032] Step 106: Perform link detection; In the initial state after frequency band allocation, each link is in a listening state, performing channel idle detection (CCA), and each link is allocated at least one antenna to receive and detect WIFI signals and non-WIFI signals on the channel.

[0033] Step 107: Determine if there is a link with an idle channel. If yes, proceed to step 108; otherwise, return to step 106 and continue link detection. Step 108: Determine if there is a conflict between sending queue 1 and queue 2; if yes, proceed to step 109; if no, proceed to step 110. Does queue 1 and queue 2 conflict? That is, queue 1 and queue 2 both have radio frames to send at the same time, and the channels of link 1 and link 2 are both in an idle state. Step 109: Use the wireless air interface collision TX direction scheduling algorithm to select the transmission link and execute step 111; The scheduling algorithm for wireless air interface collisions in the TX direction is as follows: Figure 3 As shown, this will be explained below.

[0034] Step 110: Select an idle link in the channel, and then proceed to step 111; Step 111: Switch all wireless resources (including frequency resources) and radio frequency resources to this link to ensure that data transmission can exclusively occupy resources and thus transmit wireless frames.

[0035] The process described above of switching all wireless resources (including frequency resources) and radio frequency resources to this link is as follows: Figure 4 As shown, before the handover, the basic service set BSS, with service set identifier SSID1, uses bandwidth B; after the handover, the basic service set BSS1 (SSID1) uses bandwidth B1, and the basic service set BSS1 (SSID1) uses bandwidth B2. B1 and B2 are obtained by dividing B equally.

[0036] Step 112: Prepare to receive wireless frames.

[0037] Step 113: Determine if a wireless frame is to be received; if there is a wireless frame to be received, proceed to step 115; otherwise, proceed to step 114. Here, a wireless frame to be received refers to a wireless frame whose target address is this device; if a wireless frame whose target address is not this device is received, then step 114 is executed. Step 114: Discard the wireless frame and do not process it.

[0038] In step 114, wireless frames whose destination MAC address is not that of the device are not processed and are discarded directly.

[0039] Step 115: Determine if there is a collision in the receiving link; if not, proceed to step 117; if yes, proceed to step 116. Step 115 determines whether both Link 1 and Link 2 have radio frames to receive. If there is no conflict, meaning only one link has data to receive, then proceed to step 117; otherwise, proceed to step 116.

[0040] Step 116: Using the wireless air interface collision RX direction scheduling algorithm, select the target link to receive the wireless frame based on the air interface resource allocation weight ratio, and then proceed to step 117.

[0041] The scheduling algorithm for wireless air interface collisions in the RX direction is as follows: Figure 5 As shown, this will be explained below.

[0042] Step 117: Switch all antenna and radio frequency resources to the corresponding links to ensure that resources are precisely matched with reception requirements and to receive wireless frames.

[0043] The process of switching all antenna and radio frequency resources to the corresponding link described above is as follows: Figure 4 As shown.

[0044] Step 118: Determine whether the frequency band merging conditions are met. If yes, proceed to step 119; otherwise, proceed to step 101. The frequency band merging condition is as follows: the number of access sites or the number of sites that meet the downlink throughput requirements falls below the corresponding preset threshold and remains below it for a second preset duration.

[0045] Specifically, it can be a state where the number of access stations is less than a first preset value, or less than a second preset value, and the downlink throughput of the access stations is greater than or equal to a third preset value, and this state lasts for a second preset duration.

[0046] The frequency merging conditions set in this embodiment are as follows: When the number of access stations is less than 32, or the number of stations with downlink throughput of less than 1Mbps is less than 16, and this state lasts for 5 minutes.

[0047] Step 119: Trigger the recycling mechanism to merge sub-bandwidth B1 and sub-bandwidth B2, restoring them to the single basic service set (BSS) state, and then execute step 101.

[0048] like Figure 3 The diagram shown is a flowchart of a wireless air interface collision scheduling algorithm based on TX collision detection at the transmitting end, according to an embodiment of this application. The algorithm includes the following steps: Step 301: When sending a wireless frame, if it is found that both queue 1 and queue 2 have wireless frames to send, and both link 1 and link 2 are available, then the wireless air interface collision scheduling algorithm needs to be used to select the link. Step 302: After a conflict is detected, determine if there is a link whose priority flag primary bit is set to 1. If so, proceed to step 303; otherwise, proceed to step 305. Here, the priority flag is set to 1 to indicate high priority. This application is not limited to a value of 1; other values ​​may also be used. In this application, such values ​​used to identify high priority are collectively referred to as the first set value.

[0049] Step 303: Select the link where primary is set to 1, and proceed to step 304; Step 304: For each radio frame sent, increment the radio frame count for that link by 1; Step 305: Generate random numbers, with values ​​ranging from 1 to 10; Step 306: If the random number is less than or equal to (link 1 weight ratio × 10), proceed to step 307; otherwise, proceed to step 309. Step 307: Select link 1 to send a wireless frame. After sending the wireless frame, increment the wireless frame count for that link by 1. Step 309: Select link 2 to send a wireless frame. After sending the wireless frame, increment the wireless frame count of that link by 1. Step 311: Set a timer. Every 10ms, if the link's radio frame count does not change under the conditions in step 301, then increment the link's starvation value by 1. If the link's radio frame count changes, then decrement the link's starvation value by 1, until it reaches 0. Step 312: If the starvation value of the link increases by 1 every 30ms, then proceed to step 313; otherwise, proceed to step 311 and continue monitoring the link starvation value. Step 313: Set the priority (primary=1) bit of the link to 1 for 15ms; after 15ms, restore the priority bit to 0.

[0050] Here, the priority flag is set to 0 to indicate low priority. This application is not limited to a value of 1; other values ​​may also be used. In this application, such values ​​used to identify low priority are collectively referred to as the second set value.

[0051] like Figure 5 The diagram shown is a flowchart of a wireless air interface collision scheduling algorithm based on receiver RX collision detection, according to an embodiment of this application. The algorithm includes the following steps: Step 501: When a conflict occurs between the receiving tasks of Link 1 and Link 2, the air interface collision scheduling algorithm is used to select a link to receive the radio frame based on the weight ratio; Step 502: After a conflict is detected, first check which link's priority flag (primary bit) is set to 1, then proceed to step 503; if no link has a primary flag set to 1, then proceed to step 505. Step 503: Select the link where the primary is set to 1, and proceed to step 504; Step 504: For each received radio frame, increment the radio frame count for that link by 1; Step 505: Generate a random number, with a value range of 1 to 10, and then proceed to step 506; Step 506: If the random number is less than or equal to (link 1 weight ratio × 10), proceed to step 507; otherwise, proceed to step 509. Step 507: Select link 1 to receive radio frames. After receiving a radio frame, increment the radio frame count for link 1 by 1. Step 509: Select link 2 to receive radio frames. After receiving a radio frame, increment the radio frame count for link 2 by 1. Step 511: Set a timer. Every 10ms, if the link's received radio frame count remains unchanged under the conditions in step 501, increment the link's starvation value by 1. If the link's received radio frame count changes, decrement the link's starvation value by 1, until it reaches 0. Step 512: If the starvation value of the link increases by 1 every 30ms, then proceed to step 513; otherwise, proceed to step 511 and continue monitoring the link starvation value. Step 513: Set the priority (primary=1) bit of this link to 1 for 15ms; after 15ms, restore the priority bit to 0.

[0052] Based on the same inventive concept, embodiments of the present invention also provide an air interface load balancing device based on frequency band division, which achieves air interface load balancing through the above-described air interface load balancing method based on frequency band division.

[0053] The device is a wireless access point, a wireless router, or an ONU gateway.

[0054] Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An air interface load balancing method based on frequency band allocation, characterized in that, include: Dynamically monitor the number of access sites and downlink throughput, and sort all access sites according to the wireless transmission negotiation rate. When the frequency band allocation conditions are met, the frequency band allocation operation is triggered: two basic service sets are created, the current frequency band is divided into two sub-bandwidths and allocated to the two basic service sets respectively, and the sites ranked higher are migrated to one basic service set and the sites ranked lower are migrated to the other basic service set; the frequency band allocation conditions are: the number of access sites and the number of sites that meet the downlink throughput requirements both reach the corresponding preset thresholds and remain at the first preset duration, and one sub-bandwidth corresponds to one link; Data transmission and reception are performed using a single radio frequency and time-division multiplexing mechanism. During data transmission and reception, the link status follows the principle of mutual exclusion and availability, and only one link is available at any given time and exclusively occupies all radio and radio frequency resources.

2. The method according to claim 1, characterized in that, The method further includes: The air interface resource allocation weight ratio of the two links is preset. When both links have radio frames to be transmitted at the same time and are both in an available state, or when the receiving tasks of the two links exist at the same time, it is determined that a task conflict has occurred. When a task conflict occurs, the corresponding target link is selected to perform the data transmission task or the data reception task by combining the air interface resource allocation weight ratio and the link priority identifier.

3. The method according to claim 1, characterized in that, The method further includes: When the number of access sites or the number of sites that meet the downlink throughput requirements falls below the corresponding preset threshold and remains below the threshold for a second preset duration, the two sub-bandwidths are merged and the system is restored to a single basic service set.

4. The method according to claim 1, characterized in that, The two new basic service sets include: Create two new basic service sets while keeping the original service set identifier (SSID) unchanged.

5. The method according to claim 2, characterized in that, The two links are the first link and the second link; Based on the air interface resource allocation weight ratio and link priority identifier, the appropriate target link is selected to perform the data transmission task, including: Check if there is a link whose link priority identifier is set to the first set value. If so, select the link directly and increment the transmission count of the link by 1 after each radio frame is transmitted. If no link exists, a random number is generated. If the generated random number is less than or equal to the weight ratio of the first link, the first link is selected to perform the data transmission task. Otherwise, the second link is selected to send the data, and the transmission count of the corresponding link is incremented by 1 after transmission.

6. The method according to claim 2, characterized in that, The two links are the first link and the second link; During the channel sensing phase, when the first link and the second link simultaneously detect a radio frame to be received with the target address of this device, it is determined to be a receiving task conflict. Check if there is a link whose link priority identifier is set to the first value. If so, select the link to receive and increment the receive count of the link by 1 after each radio frame is received. If it does not exist, generate a random number; If the random number is less than or equal to the weight ratio of the first link, then the first link is selected for reception; otherwise, the second link is selected for reception, and the reception count of the corresponding link is incremented by 1 after reception. If the target address of a wireless frame is not detected to be this device, it will be discarded without further processing.

7. The method according to claim 5 or 6, characterized in that, The method further includes: Set a timer to check the transmission count of the link once every first detection period. If the transmission count does not change, increment the starvation value of the link by 1. If the transmission count changes, decrement the starvation value by 1 until it reaches zero. If the hunger value corresponding to a link continues to increase for the third consecutive detection period, the priority flag of that link is set to the first preset value. After the second detection period, the priority flag is restored to the second preset value. The first detection period is shorter than the second detection period, and the second detection period is shorter than the third detection period.

8. The method according to claim 1, characterized in that, Data transmission and reception are performed using a single radio frequency and time-division multiplexing mechanism, including: A single radio frequency combined with time-division multiplexing mechanism is adopted. The two links are initially in the listening state. When the channel is detected to be idle, they enter the data transmission and reception state. A polling mechanism and a buffer queue are used for frame transmission.

9. An air interface load balancing device based on frequency band allocation, characterized in that, Air interface load balancing is achieved using the air interface load balancing method based on frequency band division as described in any one of claims 1-8.

10. The device according to claim 9, characterized in that, The air interface load balancing device is a wireless access point, a wireless router, or an ONU gateway.

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