Method and apparatus for coordinated transmission opportunity sharing in a wireless network

Abstract

Methods and apparatuses for coordinated transmit opportunity sharing in a wireless network are disclosed. In one embodiment, a method includes receiving, at an access point (AP), a signal from each of one or more neighboring APs, the signal containing a value of one or more parameters related to data transmission, determining, at the AP, whether the value of the one or more parameters is greater than a respective predetermined threshold of the one or more parameters, in response to the value of the one or more parameters being greater than the respective predetermined threshold, the AP selecting one or more Co-APs from the one or more neighboring APs as a first set of Co-APs for sharing a transmit opportunity (TXOP) in a subsequent transmission of the AP.

Description

Technical Field

[0001] This application relates to wireless air interface technology, and more particularly to methods and apparatus for coordinating the sharing of transmission opportunities in a wireless network. Background Technology

[0002] In May 2019, the IEEE 802.11 task group began developing a new Wi-Fi standard called IEEE 802.11be (or Wi-Fi 7). One of the key medium access control (MAC) features supported by the Wi-Fi 7 standard is coordinated transmit opportunity (Co-TXOP) sharing, which allows access points (APs) that compete for a TXOP through channel contention to share their TXOP duration or bandwidth with a group of coordinated APs (Co-APs). When each Co-AP sharing a TXOP provides a portion of the TXOP bandwidth for the entire TXOP duration by the TXOP owner, the resulting TXOP sharing type is called coordinated orthogonal frequency division multiple access (Co-OFDMA).

[0003] By utilizing a shared TXOP (Turn-Only Graph) from other Co-APs, Co-TXOP sharing is expected to reduce the average or standard deviation of the channel access delay for Co-APs. However, when using Co-OFDMA, the duration of PPDU (Physical Layer Protocol Data Unit) transmission by the TXOP-owning AP may increase due to the transmission of PPDUs over reduced bandwidth. Furthermore, Co-OFDMA requires the exchange of control or overhead frames necessary for multi-AP coordination. Therefore, Co-TXOP sharing based on Co-OFDMA involves a trade-off between reduced channel access delay and increased PPDU transmission duration, as well as the additional control frame exchange.

[0004] Therefore, when using Co-TXOP sharing in a wireless network, it is necessary to optimize the total frame transmission latency. Summary of the Invention

[0005] This application improves the average or standard deviation of the total frame delivery delay shared via Co-TXOP by efficiently enabling or disabling Co-TXOP sharing and appropriately selecting one or more Co-APs, such that the AP can share the AP's TXOP with the one or more Co-APs via Co-OFDMA.

[0006] In one aspect, a method is provided, comprising: receiving a signal at an access point (AP) from each of one or more neighboring APs, the signal containing values ​​of one or more parameters related to data transmission; determining at the AP whether the values ​​of the one or more parameters are greater than respective predetermined thresholds for the one or more parameters; and in response to the values ​​of the one or more parameters being greater than the respective predetermined thresholds, the AP selecting one or more Co-APs from the one or more neighboring APs as a first Co-AP set for sharing a transmission opportunity (TXOP) in subsequent transmissions at the AP.

[0007] On the other hand, an access point (AP) is provided, comprising: a processor for performing the methods described above.

[0008] On the other hand, a non-transitory processor-readable medium is provided, wherein executable instructions are tangibly stored, which, when executed by a processor, cause the processor to perform the methods described above. Attached Figure Description

[0009] The accompanying drawings, by way of example, illustrate exemplary embodiments of this application, wherein:

[0010] Figure 1 This is a block diagram of a wireless network, illustrating an exemplary environment in which the exemplary embodiments provided in this application may be operated;

[0011] Figure 2 This is a flowchart illustrating the steps of a method for Co-TXOP sharing provided by an exemplary embodiment described herein;

[0012] Figure 3A This is an exemplary MAC frame format used to send buffer status information;

[0013] Figure 3B This is an exemplary measurement report frame format used to send access delay measurement results;

[0014] Figure 4 It is used for Figure 2 An exemplary structure of the access category delay information element shared by the coordinated transmission opportunity in the protocol;

[0015] Figure 5 This is a block diagram illustrating exemplary embodiments of Co-TXOP sharing enablement and Co-AP selection provided by the exemplary embodiments described herein;

[0016] Figure 6This is a block diagram illustrating an example of Co-OFDMA;

[0017] Figure 7 This is a flowchart illustrating the steps of a method for Co-TXOP sharing via Co-OFDMA;

[0018] Figure 8A It shows the use Figure 2 and Figure 6 The simulation results of the method in the figure are shown in the figure. =0;

[0019] Figure 8B It shows the use Figure 2 and Figure 6 The simulation results of the method in the figure are shown in the figure. =0.2 ms;

[0020] Figure 9 This is a block diagram of an exemplary device for Co-TXOP sharing provided in the example embodiments described herein;

[0021] Similar reference numerals may be used in different accompanying drawings to denote similar components. Detailed Implementation

[0022] Figure 1 An exemplary wireless network 100 is illustrated. Wireless network 100 may be a WLAN, a Wi-Fi network, or a next-generation Wi-Fi compatible network operating according to one or more protocols in the 802.11 family of protocols. Wireless network 100 includes multiple access points (APs) AP1 104a, AP2 104b, AP3 104c, AP4 104d, and AP5 104e, and one or more stations (STAs) 106a, 106b, 106c, 106d, and 106e.

[0023] Each of APs 104a, AP2 104b, AP3 104c, AP4 104d, and AP5 104e may include a network access interface that serves as a wireless transmit and / or receive point for STAs 106a, 106b, 106c, 106d, and 106e. Each of APs 104a, AP2 104b, AP3 104c, AP4 104d, and AP5 104e may connect to backhaul network 102, which enables data exchange between APs 104a, AP2 104b, AP3 104c, AP4 104d, or AP5 104e and other remote networks (including, for example, the Internet), nodes, routers, APs, and devices (not shown). The backbone network may include one or more routers, switches, cables, fiber optic cables, and / or other network nodes or components.

[0024] Each AP is used to receive data from one or more STAs or from the backbone network 102 via air interface 108, and to send data from one or more STAs or from the backbone network 102 to STAs via air interface 108.

[0025] Similarly, each AP can communicate with one or more neighboring APs in the wireless network 100 via air interface 108. The first AP can be a neighboring AP of the second AP, provided that the signal strength received by the second AP from the first AP is equal to or greater than a predetermined signal strength threshold (e.g., the signal sensitivity of the second AP). For example, the signal sensitivity level of the AP can be -82 dBm. The second AP can set a predetermined signal strength threshold to meet the signal quality requirements for communication between the first AP and the second AP.

[0026] For example, AP2 104b, AP3 104c, AP4 104d, or AP5 104e can be... Figure 1 For AP1 104a's neighboring APs, as long as the signal strength of AP2 104b, AP3 104c, AP4 104d or AP5 104e received by AP1 104a is equal to or greater than a predetermined signal strength (e.g. -82 dBm).

[0027] Each of APs 104a, AP2 104b, AP3 104c, AP4 104d, and AP5 104e can communicate with their respective neighboring APs via multicast or broadcast signals on air interface 108 over a signaling channel such as a broadcast channel. The multicast or broadcast signals may include values ​​for one or more parameters, signaling data, or other control data.

[0028] Each STA in STAs 106a, 106b, 106c, 106d, and 106e is used to communicate with one or more APs in APs 104a, 104b, 104c, 104d, and 104e. For example, in Figure 1 In this configuration, STA 106a can communicate with both AP2 104b and AP3 104c, and STA 106c can communicate with AP1 104a and AP4 104d. Each of STAs 106a, 106b, 106c, 106d, and 106e can be used to receive data from or send data to one or more of the following APs via air interface 108: AP1 104a, AP2 104b, AP3 104c, AP4 104d, and AP5 104e.

[0029] Each of STAs 106a, 106b, 106c, 106d, and 106e can be a laptop computer, desktop PC, PDA, Wi-Fi phone, wireless transmit / receive unit (WTRU), mobile station (MS), mobile terminal, smartphone, mobile phone, sensor, Internet of Things (IoT) device, user equipment, or other wireless-enabled computing or mobile device.

[0030] Figure 2 Exemplary steps of a method 200 for Co-TXOP sharing in a wireless network are shown. In an example of wireless network 100, one or more APs, including AP1 104a, AP2 104b, AP3 104c, AP4 104d, and AP5 104e, can be used to transmit values ​​of one or more parameters related to data transmission between the APs and their respective neighboring APs via air interface 108. Data transmission includes packet transmission. The term "packet" refers to a Media Access Control (MAC) layer Service Data Unit (MSDU).

[0031] Parameters may include the average channel access delay for each access category (AC) of enhanced distributed channel access (EDCA) over a given time period between adjacent APs. Each AP is used to determine the average channel access delay for frames transmitted from each EDCA AC within a sliding time window.

[0032] In some examples, the parameters may also include the current queue length (i.e., buffer state), which refers to the queue length of each EDCA AC of the AP when the parameters are sent to the AP's neighboring APs. The current queue length of each EDCA AC of the AP may be the sum of downlink (DL) traffic waiting in the queue and estimated uplink (UL) traffic until the AP can send traffic.

[0033] Through EDCA, high-priority services have a higher chance of transmission than low-priority services. For example, on average, a site with high-priority services waits less time before sending its packets than a site with low-priority services. For instance, a shorter arbitration inter-frame space (AIFS) can be used for higher-priority packets. The priority level in EDCA is called the access category (AC). The contention window (CW) can be set based on the expected traffic in each AC.

[0034] The parameter value can be transmitted in beacon frames from one or more neighboring APs on air interface 108. The beacon frames can be transmitted in the signal. The parameter value can be periodically multicast or broadcast by one or more APs among AP1 104a, AP2 104b, AP3 104c, AP4 104d, and AP5 104e. Multicasting or broadcasting the parameter value can be performed using IEEE 802.11 standard measurement report frames or quality of service (QoS) empty frames. Each IEEE 802.11 standard measurement report frame and QoS empty frame includes a frame header containing buffer status information in the QoS control field or high throughput (HT) control field. Each QoS empty frame includes an empty frame body. Each IEEE 802.11 standard measurement report frame includes a station (STA) statistics report, which carries access delay measurements for each AC of the sending AP.

[0035] Figure 3AExamples of buffer status or queue size information in the QoS control field or HT control field of MAC frame format 300 are shown. In this disclosure, the terms "buffer status," "queue length," and "queue size" are used interchangeably. Buffer status information may be included in the QoS control field 302 or the high throughput (HT) control field 304. The format of the QoS control field 302 depends on the subtype 306 of the frame carrying the QoS control field. In one example, for a QoS empty frame transmitted by a non-AP STA, bits 8 through 15 of the QoS control field 302 indicate the queue size 308 of the traffic identifier (TID) indicated in bits 0 through 3, where each TID corresponds to a certain EDCA AC. APs may use the same frame subtype format to inform neighboring APs of their current buffer status information for a given TID. Queue size or buffer status information may also be included in the HT control field 304. The HT control field 304 includes control information 309, which includes variables control 1 through control N. Each control variable in control variables 1 through N 310 may include a control identification (ID) and control information. In one example, when control ID=3, the control information includes a cache status report 314 indicating a queue size high 316 and a queue size full 318. The queue size high 316 is equal to the queue size of the AC with the AC index (ACI) indicated in the ACI high field, and the queue size full 318 is equal to the sum of the queue sizes of all ACs specified in the ACI bitmap field.

[0036] Figure 3B The format of measurement report frame 330 is illustrated. Measurement report frame 330 contains a STA statistics report, which includes access latency measurement results. Measurement report frame 330 includes measurement report elements. Each measurement report element includes a measurement report field 331. The measurement report field includes a group ID 332, which indicates the type of statistics included in the statistics group data field. When group ID 332 equals 10, the statistics group data field includes access latency measurement result information 336 for each AC.

[0037] exist Figure 4In the example, in each beacon frame transmitted by one or more adjacent APs, the frame header may include an Information Element (IE) 350 for carrying average access delay information. In this example, IE 350 indicates the average channel access delay encountered by frames transmitted from each EDCA AC during the sliding window. IE may include: an element ID 352, having one octet to uniquely identify IE 350 in the wireless network 100; a length field 354 of IE 350, having one octet to indicate the length of the IE; and AC access delay 356, having four octets. Each octet of AC access delay 356 indicates the average access delay of the AC, such as AC_BE 356a, AC_BK 356b, AC_VI 356c, and AC_VO 356d, etc.

[0038] The access latency value for a specified AC in the Basic Service Set (BSS) AC access latency IE can be scaled in the following ways:

[0039]

[0040]

[0041] 255 indicates that the AP did not send any frames from the designated AC during the measurement window; 254 indicates that the AP did not send any frames from the designated AC during the measurement window, which is a result of continuous channel access delay due to high-priority AC transmissions, as required by the clear channel assessment (CCA) mechanism. The term "BSS" refers to a single wireless network operating according to the Wi-Fi protocol.

[0042] refer to Figure 2After one or more APs, such as AP1 104a, AP2 104b, AP3 104c, AP4 104d, and AP5 104e, transmit a signal containing values ​​of one or more parameters related to data transmission of the one or more APs on air interface 108, in step 202, one or more of AP1 104a, AP2 104b, AP3 104c, AP4 104d, and AP5 104e receive a signal containing values ​​of one or more parameters from their respective neighboring APs via air interface 108. In a wireless network, an AP can have one or more neighboring APs. Each AP can receive the values ​​of parameters from its neighboring APs by listening to the values ​​of parameters broadcast or multicast on air interface 108. For example, AP1 104a can be used to listen to beacon frames broadcast on air interface 108 by neighboring APs (e.g., one or more of AP2 104b, AP3 104c, AP4 104d, and AP5 104e), and receive parameter values ​​from the beacon frames of neighboring APs (e.g., one or more of AP2 104b, AP3 104c, AP4 104d, and AP5 104e) through air interface 108. As described above, multicast or broadcasting of parameter values ​​can be performed using IEEE 802.11 standard measurement report frames or QoS empty frames carrying STA statistical reports.

[0043] After the AP receives the values ​​of one or more parameters from a neighboring AP, in step 204, the AP can determine whether the value of the one or more parameters is greater than its respective predetermined threshold.

[0044] In the example in Table 1 below, each AP in the wireless network uses its Medium Access Control (MAC) addresses m1, m2, ..., m n And be uniquely identified. One or more parameters may include the first... The first adjacent AP Average access latency of each EDCA AC and / or current queue length :

[0045] Table 1

[0046]

[0047] An AC (Account Selector) consists of four indices: 1. Voice (VO), 2. Video (VI), 3. Best Effort (BE), and 4. Background (BK). ACs with smaller indices have higher priority. For example, the first AC (Voice) has higher priority than the second AC (Video).

[0048] If the values ​​of one or more parameters of one or more neighboring APs are greater than their respective predetermined thresholds, then in step 206, the AP can select one or more Co-APs from the neighboring APs as a first Co-AP set for sharing TXOPs in subsequent transmissions of the AP. By selecting one or more Co-APs as the first Co-AP set, the AP enables Co-TXOP sharing with those one or more Co-APs.

[0049] In some examples, if the average access latency received from neighboring APs exceeds a predetermined threshold of the EDCA AC, the AP or the TXOP owner AP can select a Co-AP set. Adjacent APs in the network can be considered as candidate Co-APs sharing a TXOP.

[0050] In some examples, AP (e.g., AP1 104a) can use the... Each AC competes for access to the channel, among which AP determines the first Co-AP set. This includes an index of all Co-APs that the AP considers for Co-TXOP sharing in subsequent transmissions. The AP can determine this by using the average access latency of neighboring APs. gather:

[0051] (1)

[0052] in, It is the first The first Co-AP Average access latency of each AC This is a threshold specified for each AC. Formula (1) indicates that if the average access delay of adjacent APs is greater than a predetermined threshold (e.g., if the first...), the threshold is set to 1. The priority of the AC is equal to or greater than that of the AP used to obtain the TXOP. If the priority of an AC is 0 ms, 0.2 ms or higher, then the adjacent AP is selected as the Co-AP for the AP to consider for Co-TXOP sharing in its subsequent transmissions.

[0053] In some examples, if the current queue length or queue size value in the MAC frame of the EDCA AC of a neighboring AP is greater than a predetermined threshold of the EDCA AC, the AP or the TXOP owner AP can select that neighboring AP as a candidate Co-AP for sharing the TXOP. For example, an AP can determine this by using the current queue length of the data to be sent by the neighboring AP. gather:

[0054] (2)

[0055] in, It is the first The first Co-AP The queue length of each AC, This is the threshold specified for each AC. Formula (2) indicates that if the current queue length is greater than the threshold value specified for each AC, the threshold value will be determined based on the current queue length. The AC (whose priority is equal to or greater than AP) is used to obtain the TXOP. If a predetermined threshold (based on the priority of each AC) is met, then an adjacent AP is selected as a Co-AP for the AP to consider for Co-TXOP sharing in its subsequent transmissions. For example, =0 kilobytes indication, if Co-AP has to be in the first If data is sent from the queues of multiple ACs, the AP will select that Co-AP. . It can also be other integers, used to indicate if the Co-AP's first... If the current queue length of an AC exceeds a predetermined length (e.g., 5 kilobytes), the AP selects that Co-AP for consideration in subsequent transmissions for Co-TXOP sharing. .

[0056] In some examples, if the received average access latency value of a neighboring AP is greater than a first predetermined threshold, and the received current queue length value is greater than a second predetermined threshold for an EDCA AC (whose priority is equal to or greater than the priority of the AC used by the AP to acquire the TXOP), then the AP or the TXOP owner AP can select a neighboring AP as a candidate Co-AP that the AP can consider sharing the TXOP. For example, the AP can determine this by using the average access latency and the current queue length of the data to be sent by the neighboring AP. gather:

[0057] (3)

[0058] Formula (3) indicates that if the average access delay of adjacent APs is greater than a first predetermined threshold... And its current queue length is greater than AC. (Its priority is equal to or greater than that of the AC used by AP to obtain TXOP) The second predetermined threshold of the priority) If so, the adjacent AP is selected as a candidate Co-AP for the AP to consider for Co-TXOP sharing in subsequent AP transmissions.

[0059] In each of formulas (1), (2), and (3), if The set includes at least one Co-AP, i.e. The set is not empty ( If so, then Co-TXOP sharing will be enabled.

[0060] exist Figure 5 In the example shown, based on the values ​​of one or more parameters received by AP1 104 from neighboring APs AP2 104b, AP3 104c, AP4 104d, and AP5 104e, if the value of one or more parameters is greater than the corresponding predetermined threshold, then AP1 104a can use the above formulas (1), (2), or (3) to select... Candidate Co-APs AP2 104b, AP3 104c, and AP4 104d in the set are considered by AP1 104a for Co-TXOP sharing in subsequent transmissions of AP1 104a. Figure 4 In the example, the value of the parameter of AP5 104e does not meet the predetermined threshold in formula (1), (2) or (3), and AP1 104a from AP5 104e is excluded from the set. Similarly, one or more of AP2 104b, AP3 104c, AP4 104d, and AP5 104e can be selected as candidate Co-APs for consideration in subsequent transmissions of AP2 104b, AP3 104c, AP4 104d, or AP5 104e by using formulas (1), (2), or (3) above.

[0061] After Co-TXOP sharing is enabled on an AP (e.g., AP1 104a), the AP can use one of various types of Co-TXOP sharing, such as Co-OFDMA 600, Co-TDMA 350, and Co-SR 380.

[0062] If the AP uses Co-TDMA 350 and from If one or more Co-APs selected in the set share the TXOP, then after an AP acquires the TXOP through channel contention, the AP can interact with other APs for a portion of the TXOP's duration. Some Co-APs in the set share the entire bandwidth. If an AP uses Co-SR 380 with... If one or more Co-APs selected in the set share the subsequent TXOP, the APs can share the entire TXOP bandwidth for the entire TXOP duration, at the cost of reduced transmit power or the modulation and coding scheme (MCS) used.

[0063] In some examples, the AP can use Co-OFDMA with One or more Co-APs in the set share a TXOP. Figure 6 An exemplary Co-OFDMA protocol is shown. For example... Figure 6 As shown in the example, AP1 104a selects AP2 104b as the Co-AP for Co-OFDMA. After AP1 104a begins channel contention at t1, AP1 104a acquires the TXOP at t4. Figure 6 In the process, AP1 104a, as the TXOP owner AP, provides the TXOP to AP2 104b by sharing a portion of the TXOP bandwidth for the entire TXOP duration. After the channel becomes idle at t3, and after the arbitration inter-framespacing (AIFS) and backoff duration expire, at t4, AP1 104a can use control frame 502 to notify AP2 104b (which AP1 104a has selected as a Co-AP for TXOP sharing) of the information required for Co-OFDMA. For example, AP1 104a can notify AP2 104b of the TXOP channel bandwidth allocated to AP2 104b in control frame 502. At t2, AP1 104a and AP2 104b access the corresponding portions of the allocated channel bandwidth for the entire TXOP duration.

[0064] Figure 7 Exemplary steps of a method 600 for TXOP sharing via Co-OFDMA are illustrated. After the AP enables Co-TXOP sharing by selecting one or more Co-APs from one or more neighboring APs as a first Co-AP set in step 206, in step 606, the AP (e.g., AP1 104a) can select one or more sub-channels from the available TXOP bandwidth for sharing subsequent TXOPs via Co-OFDMA. Each of the one or more sub-channels supports the IEEE 802.11 standard and PPDU transmission.

[0065] Available TXOP bandwidth refers to the bandwidth that an AP obtains through channel contention for transmitting data or packets. A subchannel refers to a certain bandwidth. Wi-Fi channel, and and Completely included In the case of bandwidth, it can be referred to as bandwidth. Another sub-channel of the channel. When a punctured preamble is used, the punctured channel is considered a sub-channel of either the main channel or the non-punctured channel. For the AP, the indices of the main 20 MHz channel, main 40 MHz channel, main 80 MHz channel, and main 160 MHz channel are respectively represented as... , , and If the AP supports preamble puncturing, a unique channel index is defined for each preamble puncturing option. For example, the indices for a primary 80 MHz channel with punctured subordinate 20 MHz, the higher 20 MHz of subordinate 40 MHz, or the lower 20 MHz of subordinate 40 MHz are respectively represented as: and .

[0066] For example, based on the available TXOP bandwidth, the AP determines the set of sub-channels (denoted as...). ), in Co-OFDMA and the When multiple Co-APs are used together, the AP can use this set of sub-channels, where . The set consists of the set of all sub-channels with a TXOP bandwidth, where Each subchannel member of the set is permitted access via the IEEE 802.11 standard (e.g., via preamble punching), and excludes the first... The main 20 MHz channel of each Co-AP, .

[0067] A subchannel of the TXOP bandwidth can be selected without significantly increasing the PPDU transmission duration or PER provided to the primary STA. For example, if the AP is sending AC data (e.g., VO), the AP can select the subchannel if using a subchannel instead of the entire TXOP bandwidth results in an increase in the AP's PPDU transmission duration and control frame overhead of less than a predetermined threshold (e.g., 10%) and an increase in PER of less than another predetermined threshold (e.g., 0.1).

[0068] exist gather In the case of step 608, AP selects one or more Co-APs from the first Co-AP set as the second Co-AP set (denoted as...). ), making

[0069] (4)

[0070] AP can potentially work with Co-OFDMA Co-APs in the set share TXOP. Equation (4) indicates that APs from the first Co-AP set... Select a set of Co-APs and form a second set of Co-APs. If the TXOP owner AP uses a set If any subchannel member shares subsequent TXOPs via Co-OFDMA, then the second set The first in Each Co-AP can use one or more sub-channels with TXOP bandwidth without changing its primary 20 MHz channel. Figure 5 In the example, the second Co-AP set Including AP2 104b and AP3 104c.

[0071] In some examples, the values ​​of parameters contained in the signals received by the AP from the Co-AP via air interface 108 are used, for example The average channel access delay and / or queue length of each Co-AP in the set, and the AP can also be obtained from a second set. Select one or more Co-APs as the third set of Co-APs for Co-OFDMA. Used for Co-TXOP sharing via Co-OFDMA.

[0072] For example, if AP from Selecting a Co-AP from the set for Co-OFDMA can be done by using a maximum weighted delay priority method, which involves multiplying the received average access delay value by a constant or weight (which depends on the EDCA AC priority) and then selecting the next highest weighted delay. The Co-AP that reports the maximum weighted average access delay from the set is selected. The higher the priority of the EDCA AC, the higher its weight. For example, the priority of a VO AC is higher than that of a BK AC. Similarly, after multiplying the received average access delay value by its weight, the AP can also select two Co-APs that report the first and second maximum average access delays from the set. Select two or more Co-APs from the set as the third Co-AP set. Used for Co-OFDMA.

[0073] For example, AP from The set is selected for Co-OFDMA with the highest value of the maximum weighted average channel access delay. One Co-AP as the third Co-AP set As shown below:

[0074] (5)

[0075] in, Based on AC index The weight, It is a set The first in The first Co-AP Average channel access delay for each AC. (Symbol) Instruction No. An AC of Co-AP (whose priority is equal to or greater than the AC used by the TXOP owner to obtain the TXOP). The maximum value of the weighted average channel access delay (based on priority). This is achieved by considering only the AC (whose priority is equal to or greater than the AC used by the TXOP owner to acquire the TXOP). (priority), symbol instruct The maximum weighted average channel access delay for all Co-APs in the set.

[0076] In some examples, if the AP selects only one Co-AP for Co-OFDMA, this selection can be performed using the maximum weighted queue length. That is, after multiplying the reported queue length by a constant or weight based on the EDCA AC priority, the AP selects the Co-AP with the maximum weighted current queue length reporting the EDCA AC. Similarly, after multiplying the received queue length value by a weight, the AP can also select from two Co-APs reporting the first and second maximum queue lengths of the EDCA AC, respectively. Select two or more Co-APs from the set as the third Co-AP set. Used for Co-OFDMA.

[0077] In some examples, when both the weighted average access latency and the weighted queue length reported by the Co-AP meet the corresponding predetermined criteria, the AP can... Select one or more Co-APs from the set as the third Co-AP set. Used for Co-TXOP sharing via Co-OFDMA.

[0078] In identifying the second Co-AP set Or the third Co-AP set Then, in step 610, the AP can allocate TXOP bandwidth for use in Co-OFDMA for both the AP and the selected Co-AP. For example, the AP can allocate TXOP bandwidth for a set of Co-OFDMA applications. or Each Co-AP selects a Co-OFDMA sub-channel. This applies to both the AP and the set. All sub-channels selected by the Co-AP do not overlap. No two selected sub-channels include the common 20 MHz channel. This non-overlapping channel allocation can be performed using different methods. For example, if the TXOP owner is in the set Choose only one Co-AP (i.e. , representing the first If a Co-AP is used for Co-OFDMA, then the TXOP owner can obtain it from... The sub-channel that maximizes the effective throughput of the AP is accessed in the set, and the remaining TXOP bandwidth is allocated to the first sub-channel. Co-AP.

[0079] In some examples, the channels assigned to the AP and the selected Co-AP (referred to as...) and This can be determined as follows:

[0080] (6)

[0081] in, It is the index of the selected Co-AP. and They represent the sub-channel sets respectively. index The data rate and packet error rate (PER) of sending data to the master STA on the channel. It is the sub-channel that maximizes the effective throughput of the AP (i.e., the AP that owns the TXOP). Excluding sub-channels Then, the set of sub-channels fully included in the remaining TXOP bandwidth is the first The maximum bandwidth of a channel that a Co-AP can access.

[0082] In step 690, the AP can compete for the channel to send data, such as Figure 6 As shown at t1 in the diagram. After acquiring the channel, the AP can communicate with the data obtained in step 608 from... or One or more Co-APs selected by the set share a TXOP. or The Co-AP in step 610 can use the sub-channels of the TXOP bandwidth allocated by the AP to send data.

[0083] By appropriately enabling Co-TXOP sharing and appropriately selecting a Co-AP that can share its TXOP via Co-OFDMA, this application achieves a trade-off between reducing channel access delay and increasing PPDU transmission duration and additional control frame exchange, and minimizes the total packet delivery delay of the Co-AP.

[0084] Figure 8A and Figure 8B The computer simulation results indicate the impact of TXOP enabling method 200 and TXOP sharing via Co-OFDMA method 600 on the effective throughput and total frame delivery delay of the aggregation. The simulation for TXOP sharing via Co-OFDMA includes two Co-APs. Both Co-APs operate on a 40 MHz channel, with each Co-AP using a unique primary 20 MHz channel. In the simulation, each Co-AP serves one STA, all Co-APs are within each other's carrier sense range, and the AC used for all Co-APs is voice (VO). The application layer traffic generation rate in the simulation ranges from 10 Mbps to 60 Mbps.

[0085] like Figure 8A The simulation results show that formula (1) is used in method 200, and =0, indicating that Co-OFDMA method 600 is enabled for each TXOP of the Co-AP. In simulations using methods 200 and 600, as the AP service generation rate increases, the average total frame delay 702b, the standard deviation of the total frame delay 704b, the average AP channel access delay 706b, the standard deviation of the AP channel access delay 708b, and the standard deviation of the sum of the inter-frame spacing (IFS) and PPDU transmission duration of the Co-AP are significantly improved compared to the average total frame delay 702a, the standard deviation of the total frame delay 704a, the average AP channel access delay 706a, the standard deviation of the AP channel access delay 708a, and the standard deviation of the sum of the IFS and PPDU transmission duration 712a, respectively, without Co-TXOP sharing.

[0086] However, at low service generation rates such as 10-40 Mb / s, the average sum of the IFS and PPDU transmission durations (710b) of Co-AP using methods 200 and 600 is higher than the average sum of the IFS and PPDU transmission durations (710a) without Co-TXOP sharing. Despite this effect, in Figure 8AIn the case of Co-AP, the average total frame delay 702b and the standard deviation of total frame delay 704b are improved compared to the average total frame delay 702a and the standard deviation of total frame delay 704a when Co-TXOP sharing is not used.

[0087] like Figure 8B The simulation results show that formula (1) is used in method 200, and =0.2 ms, indicating that if the average channel access delay of the Co-AP is greater than 0.2 ms, then the Co-OFDMA method 600 is enabled for TXOP. Besides, as... Figure 8A Besides improvements in the average total frame delay 702b, the standard deviation of total frame delay 704b, the average AP channel access delay 706b, the standard deviation of AP channel access delay 708b, and the standard deviation of the sum of IFS and PPDU transmission durations of Co-AP 712b, the average total IFS and PPDU transmission durations of Co-AP 710b are also improved at low service generation rates (e.g., 10-40 Mb / s), because the average total IFS and PPDU transmission durations of Co-AP using methods 200 and 600 710b are only slightly higher than the average total IFS and PPDU transmission durations of Co-AP without Co-TXOP sharing 710a. Similarly, in Figure 8B In the case of Co-AP, the average total frame delay 702b and the standard deviation of total frame delay 704b are improved compared to the average total frame delay 702a and the standard deviation of total frame delay 704a when Co-TXOP sharing is not used.

[0088] Figure 9 An exemplary device 850 is shown that can be used to implement methods 200 and 600 described herein. Device 850 may be an access point (AP), such as AP1 104a, AP2 104b, AP3 104c, AP4 104d, and AP5 104e in wireless network 100. Other devices suitable for implementing the methods described in this disclosure may be used, and these devices may include components different from those described below. Although Figure 9 A single instance of each component is shown, but in device 850, each component may have multiple instances.

[0089] Device 850 may include one or more processors 852, such as a central processing unit (CPU), microprocessor, application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), special-purpose logic circuitry, or a combination thereof. Device 850 may also include one or more input / output (I / O) interfaces 854, which can be connected to one or more suitable input devices and / or output devices (not shown). One or more of the input devices and / or output devices may be included as components of device 850, or may be external to device 850. Device 850 may include one or more network interfaces 858 for wired or wireless communication with a network. In an exemplary embodiment, network interface 858 includes one or more wireless interfaces, such as transmitter 838 and receiver 846, which enable communication within wireless network 100. One or more network interfaces 858 may include interfaces for wired communication links (e.g., Ethernet cables) and / or wireless communication links (e.g., one or more radio frequency links) for intra-network and / or inter-network communication. For example, one or more network interfaces 858 can provide wireless communication via one or more transmitters or transmit antennas, one or more receivers or receive antennas, and various signal processing hardware and software. In this regard, one or more network interfaces 858 may include a corresponding processing system similar to device 850. In some embodiments, one or more network interfaces 858 can manage transmit and receive parameters such as transmit power and packet detection (PD) level, while in other embodiments, one or both of these parameters may be set by processor 852. In this example, a single antenna 860 is shown, which can be used as both a transmit and receive antenna. However, in other examples, there may be separate antennas for transmit and receive. One or more network interfaces 858 can be used to transmit and receive data to backhaul network 102 or to STAs 106a, 106b, 106c, 106d and 106e, user equipment, access points, receive points, transmit points, network nodes, gateways or repeaters (not shown) in wireless network 100.

[0090] Device 850 may also include one or more storage units 870, which may include mass storage units such as solid-state drives, hard disk drives, disk drives, and / or optical disk drives. Device 850 may include one or more memories 872, which may include volatile or non-volatile memories (e.g., flash memory, random access memory (RAM), and / or read-only memory (ROM)). One or more non-transitory memories 872 may store instructions for execution by processor 852, such as for performing the present disclosure. One or more memories 872 may include other software instructions, such as for implementing an operating system and other applications / functions. In some examples, one or more datasets and / or one or more modules may be provided by external memory (e.g., an external drive that communicates with device 850 via wired or wireless communication) or may be provided by transient or non-transitory computer or processor-readable media. Examples of non-transitory computer-readable media include RAM, ROM, erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), flash memory, CD-ROM, or other portable storage devices.

[0091] In some embodiments, memory 872 may store data used by processor 852 to implement the methods and operations described herein, such as parameters from neighboring APs and Co-AP sets. wait.

[0092] A bus 892 may exist to provide communication between components of device 850, including one or more controllers 852, one or more I / O interfaces 854, one or more network interfaces 858, one or more storage units 870, and one or more memories 872. Bus 892 may be any suitable bus architecture, including, for example, a memory bus, a peripheral bus, or a video bus.

[0093] Certain adaptations and modifications can be made to the described embodiments. Therefore, the embodiments discussed above are considered illustrative rather than limiting.

[0094] This disclosure provides certain exemplary algorithms and computations for implementing examples of the disclosed methods and operations. However, this disclosure is not limited to any particular algorithm or computation. Although this disclosure describes methods and processes by steps performed in a certain order, one or more steps in the methods and processes may be omitted or changed appropriately. Where appropriate, one or more steps may be performed in an order different from that described in this disclosure.

[0095] Based on the description of the above embodiments, this disclosure can be implemented solely in hardware, or it can be implemented using software and necessary general-purpose hardware platforms, or it can be implemented using a combination of hardware and software. Based on this understanding, the technical solutions of this disclosure can be embodied in the form of a software product. The software product can be stored in a non-volatile or non-transitory storage medium, which can be a compact disk read-only memory (CD-ROM), a USB flash drive, or a hard disk. The software product includes several instructions that enable a computer device (personal computer, server, or network device) to execute the methods provided in the embodiments of this disclosure.

[0096] Although this disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations may be made without departing from the scope of this disclosure as defined in the appended claims.

[0097] Furthermore, the scope of this application is not limited to the specific embodiments of the processes, machines, articles of manufacture, material compositions, modules, methods, and steps described in the specification. It will be readily understood by those skilled in the art that existing or soon-to-be-developed processes, machines, articles of manufacture, material compositions, modules, methods, or steps that have substantially the same functionality as the corresponding embodiments described herein, or that can achieve substantially the same results as the embodiments described, can be used in accordance with this disclosure. Therefore, the appended claims are intended to include such processes, machines, articles of manufacture, material compositions, modules, methods, or steps within their scope.

Claims

1. A method for coordinating transmission opportunity sharing in a wireless network, characterized in that, The method includes: At the access point (AP), a signal is received from each of one or more neighboring APs, the signal containing the value of one or more parameters related to data transmission, wherein the one or more parameters include the average channel access delay of frames transmitted from each of one or more access classes (ACs) of Enhanced Distributed Channel Access (EDCA) within a sliding time window of each of the one or more neighboring APs. At the AP, determine whether the value of one or more parameters is greater than a predetermined threshold for each of the one or more parameters; In response to the value of one or more parameters being greater than the respective predetermined threshold, the AP selects one or more Co-APs from the one or more neighboring APs as a first Co-AP set for sharing a transmission opportunity (TXOP) in subsequent transmissions of the AP, wherein if the received average access delay value of the neighboring APs is greater than a predetermined threshold of the EDCA AC, the AP selects a neighboring AP from the first Co-AP set as a candidate Co-AP for sharing the TXOP.

2. The method according to claim 1, characterized in that, The respective predetermined thresholds include a threshold that is 0 ms or greater than 0 ms.

3. The method according to claim 1, characterized in that, The one or more parameters include the current queue size of one or more access classes (ACs) for Enhanced Distributed Channel Access (EDCA) of each of the one or more adjacent APs.

4. The method according to claim 3, characterized in that, Each of the predetermined thresholds includes a threshold that is 0 kilobytes or greater than 0 kilobytes.

5. The method according to claim 1, characterized in that, For one or more Access Classes (ACs) of Enhanced Distributed Channel Access (EDCA) for each of the one or more adjacent APs, the one or more parameters include a first parameter of average channel access delay and a second parameter of current queue size.

6. The method according to claim 5, characterized in that, The first parameter is associated with a first predetermined threshold, which is 0 ms or greater than 0 ms; the second parameter is associated with a second predetermined threshold, which is 0 kilobytes or greater than 0 kilobytes.

7. The method according to claim 5, characterized in that, The one or more parameters are periodically multicast or broadcast by each of the one or more adjacent APs using beacon frames, IEEE 802.11 standard measurement report frames, or quality of service (QoS) empty frames.

8. The method according to claim 7, characterized in that, The beacon frame includes BSS AC delay information elements, the IEEE 802.11 standard measurement report frame includes the IEEE 802.11 standard STA statistics report and the frame header of the IEEE 802.11 standard measurement report frame, or the quality of service (QoS) empty frame includes buffer status information in the QoS control field or the high throughput (HT) control field.

9. The method according to claim 8, characterized in that, The STA statistics report includes the average access latency of one or more AC types among Best-effort Service (BE), Background (BK), Video (VI), and Voice (VO), or the QoS control field or the HT control field includes the current queue size of one or more AC types among BE, BK, VI, and VO.

10. The method according to any one of claims 1 to 9, characterized in that, The AP shares the TXOP with one or more Co-APs via Co-OFDMA.

11. The method according to claim 10, characterized in that, The method further includes: the AP selecting one or more sub-channels from the available TXOP bandwidth for the AP to share the TXOP via Co-OFDMA, wherein each of the one or more sub-channels supports IEEE 802.11 standard and physical layer protocol data unit (PPDU) transmission.

12. The method according to claim 11, characterized in that, When the AP uses any of the one or more sub-channels to send AC data, the increase in PPDU transmission duration and control frame overhead is less than a third predetermined threshold, and the increase in PER is less than a fourth predetermined threshold.

13. The method according to claim 11, characterized in that, The method further includes: The AP selects a second Co-AP set from the first Co-AP set, wherein each Co-AP in the second Co-AP set accesses a primary 20 MHz channel, and the primary 20 MHz channel is not included in at least one of the one or more sub-channels selected by the AP for possible TXOP sharing via Co-OFDMA.

14. The method according to claim 13, characterized in that, The method further includes: The AP selects a third Co-AP set from the second Co-AP set, wherein the third Co-AP set includes a Co-AP that reports the maximum weighted average access latency or the maximum weighted queue size of the EDCA AC.

15. The method according to claim 14, characterized in that, The weights of the maximum weighted average access latency or the maximum weighted queue size are based on the priority of the EDCA AC.

16. The method according to claim 14, characterized in that, The method further includes: the AP allocating a first sub-channel to the AP from the one or more sub-channels; the AP allocating a second sub-channel to each Co-AP in the third Co-AP set from the remaining available TXOP bandwidth; wherein the first sub-channel and the second sub-channel do not overlap.

17. The method according to claim 16, characterized in that, Select the sub-channel for the AP to increase the AP's effective throughput relative to other available sub-channels.

18. The method according to any one of claims 1 to 9, characterized in that, Each of the respective predetermined thresholds is associated with a first access class (AC) of Enhanced Distributed Channel Access (EDCA), and the first priority of the first AC is equal to or greater than the second priority of the second AC used by the AP to acquire the TXOP.

19. The method according to any one of claims 1 to 9, characterized in that, The AP shares the TXOP with one or more Co-APs via Co-Time Division Multiple Access (Co-TDMA).

20. The method according to any one of claims 1 to 9, characterized in that, The AP shares the TXOP with one or more Co-APs through Co-Speed ​​Frequency Reuse (Co-SR).

21. An access point (AP), characterized in that, The AP includes: A processor for performing the method according to any one of claims 1 to 9.

22. A non-transient processor-readable medium, characterized in that, The non-transitory processor-readable medium tangibly stores executable instructions that, when executed by a processor, cause the processor to perform the method according to any one of claims 1 to 9.

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