WO2014183401A1

WO2014183401A1 - Channel access method and access device

Info

Publication number: WO2014183401A1
Application number: PCT/CN2013/087307
Authority: WO
Inventors: 林英沛; 张佳胤; 杨讯; 马驰翔
Original assignee: 华为技术有限公司
Priority date: 2013-05-16
Filing date: 2013-11-18
Publication date: 2014-11-20
Also published as: CN104168662B; CN104168662A

Abstract

Disclosed are a channel access method and an access device. The method comprises: an access device determining another access device capable of using a channel in collaboration with the access device as a collaborative access device; the access device monitoring use states of channels the collaborative access device accesses, and determining a channel capable of being used by the access device among the channels used by the collaborative access device as a collaborative available channel; and the access device transmitting data in transmission channels comprising the collaborative available channel. In the embodiments of the present invention, an access device can use a collaborative available channel of a collaborative access device as a transmission channel of the access device to transmit data, and a same channel can be simultaneously accessed by multiple access devices, thereby improving the spectrum utilization rate and reducing the network congestion.

Description

Channel access method and access device

The present invention relates to the field of wireless communications, and in particular, to a channel access method and an access device in a wireless local area network scenario. Background technique

With the development of communication-related technologies, the Wireless Local Area Network (WLAN) technology based on the IEEE 802.11 standard has been widely used because: On the one hand, the existing networks of mobile operators are difficult to bear hugely. The data traffic needs to be effectively offloaded by the WLAN network. On the other hand, the low cost of the WLAN network attracts more and more users to select the WLAN network for data service interaction.

Wi-Fi networks use unlicensed bands. This open frequency band is difficult to obtain QoS (Quality of Service) guarantee for spectrum use, and the spectrum resources are limited. Moreover, with the increasing popularity of smart terminals such as portable computers and smart phones supporting WLAN technology, WLAN bands are increasingly congested. Therefore, at present, the development and evolution of WLAN network technology is mainly aimed at improving spectrum utilization efficiency and interference management capability.

IEEE 802.11 adopts Carrier Sense Multiple Access with Collision Avoid (CSMA) mechanism to access multiple channels in a competitive manner to avoid collisions. The random backoff mechanism can effectively avoid the occurrence of collisions. Specifically, when the network load is large, when multiple APs or STAs need to send data on a certain channel at the same time, only one AP or STA can access the channel at a time, and other APs or STAs need to Wait for the channel to become idle. At this time, there may be a state in which a plurality of APs or STAs are ready to access the channel at the same time. The carrier sense mechanism with collision avoidance mentioned above makes it necessary to transmit data.

The AP or the STA accesses the channel in turn, and minimizes the collision conflict of the access channel at the same time. When the number of APs or STAs is small, the system can effectively ensure the normal operation of the system. However, when the number of APs or STAs is large, due to the exclusiveness of channel access, only one AP or STA can access the channel at a time, resulting in low spectrum utilization and network congestion. Summary of the invention

The present invention is to solve the problem that the channel resources are not fully utilized when the device accesses and uses the channel in the WLAN.

In order to solve the above technical problem, according to an embodiment of the present invention, in a first aspect, a channel access method is provided, including:

The access device will be determined to be a cooperative access device with other access devices that cooperate with the channel;

The access device monitors a usage status of a channel accessed by the cooperative access device, and determines, in a channel used by the cooperative access device, a channel that can be used by the access device as a cooperative available channel; as well as

The access device performs data transmission on a transport channel including the cooperative available channel.

With reference to the first aspect, in a possible implementation manner, the access device is configured to be a cooperative access device by using another access device that can cooperate with the channel, including:

The access device parses the physical layer convergence process protocol data unit PPDU and/or the medium access control MAC frame header of the other access device, and obtains address information of the other access device, where the address information includes basic services. a set identifier; if the address information is included in a cooperative access set of the access device, the access device determines the other access device as the cooperative access device Ready.

With reference to the first aspect, in a possible implementation, the channel that can be used by the access device in the channel used by the collaboration access device is determined as a cooperative available channel, including:

The access device monitors and obtains a service set identifier of the other access device;

If the service set identifier of the other access device is the same as the access device and the extended service set to which the service set identifier belongs supports cooperative transmission, H'J determines the other access device as the collaboration Access device.

If the network allocation vector of the channel in which the cooperative access device competes for obtaining the usage right is greater than or equal to the set threshold, determining, by the cooperative access device, the channel that has obtained the usage right is determined as the cooperative available channel.

With reference to the first aspect, in a possible implementation manner, the method further includes: if the access device competes for obtaining the right to use the channel accessed by itself, the access device is competitively obtained. The own available channel of the right and the cooperative available channel are jointly determined as the transport channel.

With reference to the first aspect, in a possible implementation manner, the determining, by the access device, the self-available channel that obtains the usage right and the cooperative available channel are jointly determined as the transport channel, including:

If the self-available channel is adjacent to the cooperative available channel, the self-available channel and the cooperative available channel and a guard interval therebetween are used as the transport channel;

If the self-available channel is not adjacent to the cooperative available channel, the carrier-available channel and the cooperative available channel are used as carrier aggregation manners. The transmission channel.

With reference to the first aspect, in a possible implementation manner, the accessing, by the access device, data transmission on a transport channel including the cooperative available channel includes:

The access device performs data transmission on the transport channel by using a cooperative transmission manner determined in negotiation with the cooperative access device.

With reference to the first aspect, in a possible implementation manner, the access device performs data transmission on the transmission channel by using a cooperative transmission manner that is determined in negotiation with the cooperative access device, and includes:

If the access device and the cooperative access device use the same channel for transmitting data, the station in the overlapping basic service set area is used in the joint transmission, CS/CB or interference-coordinated cooperative transmission mode. Any one of the data transmission on the transport channel; for any station that is outside the overlapping basic service set area, adopting any one of CS/CB or interference alignment or direct transmission cooperative transmission mode, Transmission channel for data transmission;

If the access device is different from the channel used by the cooperative access device to transmit data, any one of the CS/CB or the interference-aligned cooperative transmission mode is adopted for the sites in the overlapping basic service set regions. Transmitting data on the transport channel; using any one of a CS/CB, a perturbation alignment, or a direct transmission cooperative transmission mode for a station that is outside the overlapping basic service set area, performing on the transport channel data transmission.

With reference to the first aspect, in a possible implementation manner, before the access device is configured to be a cooperative access device by using another access device that can cooperate with the channel, the method includes:

Determining the channel accessed by the access device based on the monitored channel quality and/or the usage of the neighboring other access devices.

In a second aspect, the present invention provides an access device, including:

Collaborative device determination module for other devices that will be able to use the channel in cooperation therewith The access device is determined to be a cooperative access device;

a cooperative channel determining module, configured to monitor a usage status of a channel accessed by the cooperative access device, and determine, in a channel used by the cooperative access device, a channel that can be used by the access device as a collaboration available Channel;

And a data transmission module, configured to perform data transmission on a transmission channel including the cooperative available channel.

With reference to the second aspect, in a possible implementation manner, the collaboration device determining module includes:

a parsing sub-module, configured to parse a physical layer convergence process protocol data unit PPDU and/or a media access control MAC frame header of the other access device, to obtain address information of the other access device, where the address information includes a basic Service set identifier payment;

And a first determining submodule, configured to determine the other access device as the cooperative access device if the address information is included in a coordinated access set of the access device.

a monitoring submodule, configured to listen to obtain a service set identifier of the other access device;

a second determining submodule, configured to: if the service set identifier of the other access device is the same as the access device, and the extended service set to which the service set identifier belongs supports cooperative transmission, the other access The device is determined to be the collaborative access device.

With reference to the second aspect, in a possible implementation, the cooperative channel determining module is configured to: if the network access vector of the channel in which the cooperative access device competes for obtaining the usage right is greater than or equal to a set threshold, Determining, by the cooperative access device, a channel that has obtained the usage right is determined as the cooperative available channel. With reference to the second aspect, in a possible implementation, the cooperative channel determining module is further configured to:

If the access device competes for the right to use the channel accessed by itself, the access device competes with the available channel of the access right and the cooperative available channel to determine the transmission channel.

With reference to the second aspect, in a possible implementation manner, the cooperative channel determining module includes:

a first transport channel determining submodule, configured to: if the self available channel is adjacent to the cooperative available channel, use the self available channel and the cooperative available channel together with a guard interval therebetween Transmission channel

And a second transmission channel determining submodule, configured to use the carrier aggregation mode and the cooperative available channel as a carrier channel if the self-available channel is not adjacent to the cooperative available channel.

With reference to the second aspect, in a possible implementation, the data transmission module includes:

a cooperative transmission mode determining submodule, configured to negotiate with the cooperative access device to determine a coordinated transmission mode;

And a data transmission submodule, configured to perform data transmission on the transmission channel by using the cooperative transmission mode.

With reference to the second aspect, in a possible implementation manner, the cooperative transmission mode determining submodule is specifically configured to:

If the access device and the cooperative access device use the same channel for transmitting data, the station in the overlapping basic service set area is used in the joint transmission, CS/CB or interference-coordinated cooperative transmission mode. Any one of the cooperative transmission modes; the CS/CB, the interference alignment, or the direct transmission coordinated transmission mode is used as the cooperative transmission mode for the sites that are outside the overlapping basic service set areas; If the access device is different from the channel used by the cooperative access device to transmit data, the site used in the overlapping basic service set area is adopted.

Any one of the CS/CB or the interference-aligned cooperative transmission mode is used as the cooperative transmission mode; for the sites that are outside the overlapping basic service set areas, the CS/CB, the interference alignment or the direct transmission cooperative transmission mode is adopted. Any one of them is used as the cooperative transmission method.

With reference to the second aspect, in a possible implementation, the access device further includes:

And an access module, configured to determine, according to the monitored channel quality and/or the usage of the neighboring other access devices, the channel accessed by the access device.

Effect of the invention

The accessing device can use the cooperative available channel of the cooperative access device as its own transmission channel for transmitting data. In this embodiment of the present invention, one channel may access multiple access devices at the same time, thereby improving spectrum utilization and reducing the network. congestion.

Further features and aspects of the present invention will become apparent from the following detailed description of exemplary embodiments. DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in FIG

1 is a flowchart of a channel access method according to an embodiment of the present invention;

2 is a schematic diagram of a basic channel access rule in a channel access method according to Embodiment 2 of the present invention;

3 is a schematic diagram of a SIFS delay in a channel access method according to Embodiment 2 of the present invention; FIG. 4 is a schematic diagram of a random backoff mechanism in a channel access method according to Embodiment 2 of the present invention; 5 is a schematic diagram of a NAV principle in a channel access method according to Embodiment 2 of the present invention; FIG. 6 is a flowchart of a channel access method according to Embodiment 2 of the present invention;

7 is a schematic diagram of a partial BSSID in a channel access method according to Embodiment 2 of the present invention;

FIG. 8 is a schematic diagram showing the distribution of an AP and a STA in a channel access method according to Embodiment 2 of the present invention; FIG.

FIG. 9 is a schematic diagram of different bandwidth combinations in a channel access method according to Embodiment 2 of the present invention; FIG.

FIG. 10 is a schematic diagram of channel usage in a channel access method according to Embodiment 2 of the present invention; FIG.

11 is a schematic diagram of using a guard interval in a channel access method according to an embodiment of the present invention;

FIG. 12 is a schematic diagram of NAV in a channel access method according to Embodiment 2 of the present invention; FIG. 13 is a schematic structural diagram of an access device according to Embodiment 3 of the present invention;

FIG. 14 is a schematic structural diagram of an access device according to Embodiment 4 of the present invention. detailed description

Various exemplary embodiments, features, and aspects of the invention are described in detail below with reference to the drawings. The same reference numerals in the drawings denote the same or similar elements. The various aspects of the embodiments are illustrated in the drawings, and the drawings are not necessarily drawn to scale unless otherwise indicated.

The term "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustrative." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous.

In addition, numerous specific details are set forth in the Detailed Description of the <RTIgt; Those skilled in the art will appreciate that the present invention may be practiced without these specific details. In other instances, for large Well-known methods, means, components and circuits have not been described in detail so as to highlight the gist of the invention. Embodiment 1

FIG. 1 is a flowchart of a channel access method according to an embodiment of the present invention. As shown in FIG. 1, the channel access method includes:

Step 101: The access device determines, as the cooperative access device, other access devices that can cooperate with the channel.

Specifically, determining the cooperative access device may include: adopting the following manner: manner 1, determining according to the address information;

Specifically, the access device may parse a PPDU (Physical Layer Convergence Procedure Protocol Data Unit) and/or a MAC (Medium Access Control) frame of the other access device. Header, obtaining address information of the other access device;

If the address information is included in the coordinated access set of the access device, the access device determines the other access device as the collaborative access device;

The address information may include a BSSID (Basic Service Set Identifier); specifically, the access device may set the address information in the PPDU of the physical layer by using a basic service set identifier, so that the physical layer is parsed. The PPDU can obtain the address information, and does not need to parse the MAC, and the implementation speed is fast. Of course, it is also possible not to add address information to the physical layer, but to parse the basic service set identifier in the MAC frame header.

The cooperative access set of the access device may be a set set in advance, or may be generated by the access device according to the information of the neighboring access device collected by the access device. Method 2, according to the SSID (Service Set Identifier);

Specifically, after the access device listens to the service set identifier of the other access device, if the service set identifier of the other access device is the same as the access device and the service set identifier belongs to The ESS (Extended Service Set) supports coordinated transmission, and the other access devices are determined as the cooperative access device.

After the access device is determined to be a cooperative access device by using another access device that cooperates with the channel, the cooperative relationship of the shared channel can be established by interacting with the cooperative access device.

Step 102: The access device monitors a usage status of a channel accessed by the cooperative access device, and determines, in the channel used by the cooperative access device, a channel that can be used by the access device as a cooperative available channel. ;

The NAV (Network Allocation Vector) can indicate the time that the device can occupy the channel for which the device is entitled to obtain the right to use. If a device occupies a certain channel, the value of the N AV is large, indicating that the device can occupy the channel. For a long time, the channel is also used as a transmission channel. After the access device monitors the situation of other access devices, if other access devices access a channel and compete for the right to use the channel, the channel of the access right may be obtained according to other access devices. The AV determines whether the channel can be utilized. Specifically, the threshold may be a predetermined value. If the coordinated access device competes to obtain the NAV of the channel for which the usage right is greater than or equal to the set threshold, the cooperative access device competes. The channel from which the usage right is obtained is determined to be a cooperative available channel. The set threshold may be preset, for example: a fixed value is set according to a specific networking and implementation, and the set threshold may also be changed at any time according to specific conditions, for example: The NAV value of the present invention is determined as the threshold value, which is not specifically limited in the embodiment of the present invention. Further, if the access device competes for the right to use the channel accessed by the access device, the access device competes with the available channel of the access right and the cooperative available channel to determine the transmission channel. Specifically, it can include the following conditions:

Case 1: If the self-available channel is adjacent to the cooperative available channel, the self-available channel and the cooperative available channel and a guard interval between the two are jointly used as the transport channel;

Case 2: If the self-available channel is not adjacent to the cooperative available channel, use the carrier aggregation mode and the cooperative available channel as the transmission channel. Carrier aggregation refers to the aggregation of two or more basic carriers to meet broadband requirements. In the embodiment of the present invention, the carrier aggregation may be used to use a plurality of non-contiguous channels as the transmission channel. The specific carrier aggregation method may be implemented in multiple implementation manners, which is not limited herein.

Step 103: The access device performs data transmission on a transport channel including the cooperative available channel.

Specifically, the bandwidth used by the access device and its cooperating access device may be the same or different. After determining that an access device is a cooperative access device, the access device may first negotiate with the cooperative access device to determine a coordinated transmission mode, and then, after determining the transport channel, adopt the cooperative transmission mode, where the transmission is performed. The channel performs data transmission. The access device performs the data transmission on the transport channel by using the coordinated transmission mode determined by the cooperative access device, and may specifically include the following conditions:

Case 1: If the access device and the cooperative access device use the same channel for transmitting data, JT (Joint Transmission), CS/ is adopted for the sites in the overlapping basic service set areas. Any one of CB (Coordinated scheduling/beamforming) or IA (Interference Alignment) cooperative transmission mode And performing data transmission on the transport channel; using any one of a CS/CB, a perturbation alignment, or a direct transmission cooperative transmission mode for a station that is outside the overlapping basic service set area, performing on the transport channel data transmission;

Case 2: If the access device and the cooperative access device use different channels for transmitting data, the CS/CB or the interference-aligned cooperative transmission mode is adopted for the sites in the overlapping basic service set areas. Any one of the data transmission on the transport channel; for any station that is outside the basic service set area, the CS/CB, the interference alignment, or the direct transmission cooperative transmission mode is used. The transmission channel performs data transmission.

In addition, before the step 101, the method may further include: Step 100: The access device determines, according to the monitored channel quality and/or the usage of the neighboring access devices, the channel accessed by the access device.

The channel quality may be whether the channel is busy, the duty ratio, etc., and the usage of other neighboring access devices may include: whether other neighboring access devices can cooperate with the channel or the like.

In the channel access method of the embodiment of the present invention, the access device may use the cooperative available channel of the cooperative access device as its own transmission channel for transmitting data, and one channel may access multiple access devices at the same time, thereby improving spectrum utilization. , reducing network congestion. Further, the access device can also use the available channel, the cooperative available channel, and the guard interval between the two as a transmission channel, which can form a continuous net spectrum, realize large-bandwidth transmission, further improve spectrum utilization and reduce Network congestion. In addition, different cooperative transmission modes can not only effectively improve spectrum utilization, but also support cooperation between access devices with different bandwidths, enhance system robustness, and effectively suppress interference and increase network. Throughput.

Embodiment 2

In the embodiment of the present invention, the access device competes for obtaining the channel used by itself. The mechanism by which the rights and cooperative access devices compete to obtain the right to use the channel can be referred to.

The provisions of the IEEE-related agreement are described below.

2 is a schematic diagram of basic channel access rules in a channel access method according to Embodiment 2 of the present invention. As shown in FIG. 2, different frame spacings in IEEE 802.11 are SIFS.

(Short Inter-Frame Space, PICC), PIFS (Point Coordination Function Inter-Frame Space) and DIFS have different channel priority access levels. Among them, SIFS is used to separate the frames that need to respond and their corresponding response frames, such as: data frame and ACK (correct) response, RTS

(Request to Send, request to send) /CTS (Clear to Send) response. SIFS needs to be as short as possible to meet the various delay times of reasonable implementation, so as to reduce unnecessary system overhead and waste. FIG. 3 is a schematic diagram of a SIFS delay in a channel access method according to Embodiment 2 of the present invention. As shown in FIG. 3, the delay time includes a decoding delay of a frame (Rx) received by a PHY (Physical Layer). The processing delay of the received frame in the MAC, the time at which the response frame is established, and the start time of the transmitter transmission response (Tx). As shown in Figure 2 and Figure 3, a specific SIFS duration can be defined by the aSIFSTime parameter. Among them, in the 802 of IEEE 802.11a, 802.1 lg, and 802.1 In, the SIFS duration defined by the aSIFSTime parameter is 164 敖 seconds ( s). The length of other IFS (Inter-Frame Space) is SIFS plus an integer multiple of the slot time, and the transmission time starts at the edge of the slot. The duration of a particular PH Y can be defined by the aS lotTime parameter. Among them, in the PHYs of IEEE 802.11a, 802.1 lg, and 802.1 In, the duration of the aSlotTime parameter is 9 microseconds. The access priority of the PIFS is second only to the SIFS, and is used to obtain priority access to the channel, for example: Beacon. The PIFS duration is defined as "PIFS=aSIFSTime+aSlotTime". Access devices such as: APs or STAs use PIFS delay to obtain access to the channel to transmit beacons, start a non-contention period; or if no expected response frames are received within a non-contention period, then Obtain access to the channel. DIFS by The STAs running under the DCF are used to transmit data frames and management frames. The DIFS duration is defined as "DIFS=aSIFSTime+2 X aSlotTime,". If the AP or STA using DCF determines that the channel is idle during the DIF S period, or uses DCF. After the AP or STA correctly receives a frame, it continues to judge whether the channel is idle during the remaining backoff time after DIFS. If idle, the AP or STA access channel of the DCF is used for transmission.

When the channel changes from busy to idle, there may be multiple APs or STAs ready to send data at the same time. In order to reduce the collision conflict, the AP or STA that is ready to send data transmission selects a random backoff count as the backoff duration, and delays according to the backoff count. The random backoff count is a pseudo-random integer selected from the mean sentence distribution of the interval [0, CW]. The initial value of the CW (Contention Window) parameter is CWmin, which is doubled after each unsuccessful MPDU (MAC protocol data unit) transmission. For example: CW becomes twice as large as the ACK response frame corresponding to one data frame each time. If CW reaches the system set maximum value CWmax, CWmax is maintained until it is reset. The CW can be reset to CWmin after each successful transmission of the MPDU. Among them, the values of CW, CWmin and CWmax can be reduced by 1 ( 2 ⁿ - l ). In DCF, the values of CWmin and CWmax are specified according to the PHY used. For example: In the PHYs of IEEE 802.1 1 a, 802.1 1 g, and 802.1 1 η, the value of CWmin is 15 and the value of CWmax is 1023. Thus, the value of CW starts from 15, and after each MPDU transmission is unsuccessful, the next higher power of 2 is subtracted by 1 (that is, the value of CW is multiplied by 2) until 1023 or every time the MPDU transmission is successfully reset to 15.

At the beginning of a random backoff procedure, the AP or STA first selects a random backoff count in the range [0, CW]. After the DIFS duration, if a certain channel in the DIFS duration is judged to be idle, all APs or STAs start random backoff counting. If the channel becomes busy within a retreat time, it is retired Cheng is suspended. If the channel becomes idle again within one DIFS duration, then the random backoff count continues. FIG. 4 is a schematic diagram of a random backoff mechanism in a channel access method according to Embodiment 2 of the present invention. As shown in FIG. 4, when a STA (Station, Site) or an AP (Access Point, access point) needs to transmit data, the channel is first subjected to a certain duration, for example: "DIFS+""Retractiontime" of the interception, to the channel ^ ί, a CCA (Clear Channel Assessment), the duration is called DCF (Distributed Coordination Function) frame spacing, that is, DIFS (DCF Inter-Frame) Space, DCF frame spacing). If the channel is confirmed to be idle via the CCA, the AP or STA considers that it can use the channel to transmit data. If the channel is busy via the CCA, the AP or STA waits for the channel to become idle, delays the DIFS duration, and continues to wait for the random backoff duration. If the channel remains idle after the end of the backoff period, the AP or STA considers that it can transmit on the channel. When multiple STAs are postponed and enter the random backoff count, STA3, which is the site with the smallest random backoff count value, is selected to win the competition and start transmission first. The remaining stations suspend their own random backoff counts, waiting for the channel to become idle again. After the channel becomes idle again and waits for DIFS, the station STA4 that selects the random backoff count value is selected to access the channel for transmission. By analogy, the STA2, which has the largest random backoff count value, finally accesses the channel for transmission. In addition, if STA 1 is a newly accessed station, it may select a random backoff count from the entire CW, which may be more than the random backoff count remaining at the station that has suspended the backoff count in the previous access competition, such as STA 2. The values are large.

In order to reduce the probability of collision, the station that initiates the communication can start a short control frame exchange sequence using a modulatable RTS (Request to Send)/CTS (Clear to Send) frame to enhance the robustness of the collision detection mechanism. . This operation can reduce the collision probability and save power overhead by setting the N AV of the sender and receiver peripheral sites. RTS/CTS mechanism can effectively solve hidden Tibetan node problem. In IEEE 802.11, carrier sensing can be used to determine if a channel is available. 802.11 has two carrier monitoring functions: physical carrier monitoring and virtual carrier monitoring. As soon as one of the listening functions considers the medium to be busy, the MAC reports the result to the higher layer protocol. Among them, the physical carrier monitoring function is provided by the physical layer, depending on the medium and modulation method used. Virtual carrier monitoring can be implemented by Network Allocation Vector (NAV). 802.11 frames can contain a Duration field, which indicates the duration, used to reserve a media usage time. In addition, NAV itself is a timer that can be used to specify how much time is expected to occupy the medium or channel, in seconds. The AP or STA can set the NAV to the expected time of use, including all frames that must be used to complete the entire operation. Other APs or STAs count down the value of NAV to zero.

When the value of NAV is not zero, the virtual carrier monitoring function indicates that the medium is busy; when the value of NAV is zero, the virtual carrier monitoring function indicates that the medium is idle. The use of NAV ensures that the basic operation of the STA is not interrupted. FIG. 5 is a schematic diagram of the NAV principle in the second channel access method according to the embodiment of the present invention. As shown in FIG. 5, the bar graph on the NAV line is a NAV timer. The NAV can be carried by the frame header of the RTS frame and the CTS frame. If a NAV bar graph appears on the NAV line, the AP or STA delays access to the medium because the virtual carrier sensing mechanism will indicate that the medium is busy. In order to ensure that the entire process is not interrupted, the AP or STA at the transmitting end includes NAV in its RTS frame to prevent other STAs from accessing the channel when transmitting RTS frames.

NAV is zero. However, since not every AP or STA on the network receives these RTS frames, the AP or STA at the receiving end will return a CTS frame response to the RTS frame. The NAV is also included in the CTS frame, but the NAV in the CTS frame is shorter than the time in the RTS frame. The use of NAV can prevent other APs or STAs from accessing the channel during transmission until the end of the transmission process during the NAV period. Once the entire process is completed, Line access, that is, enter the competition window shown in Figure 5.

FIG. 6 is a flowchart of a method for accessing a channel according to an embodiment of the present invention. As shown in FIG. 6 , in the second embodiment, an access device and other access devices are used as an access device, and the access device is an AP. The cooperative access device is AP2, and the AP2 may be one or more, and the present invention is not limited. The API determines the final available channel bandwidth by listening to the channel that it has accessed and the channel of the adjacent and capable AP2. When AP I discovers an accessible channel, it can first access the channel. After accessing the channel, the AP I listens to each neighboring AP and confirms whether the neighboring AP can cooperate with the AP. Assume that the adjacent AP2 is an AP that can cooperate, and the AP I further interacts with the information of the AP2 to confirm whether the channel that the AP2 has obtained the usage right can be used by itself. If it is possible, the channel that AP2 is competing for the right to use is the cooperative available channel of AP I. Then, the AP I can also determine whether the AP2 cooperative available channel and its own contention have obtained the right to use the channel, that is, whether the available channel is adjacent to itself. If adjacent, the AP I can also use its own available channel, guard interval, and AP2. The cooperative available channels are collectively used as their own transmission channel; if not adjacent, AP I can use its own available channel and cooperative available channel by carrier aggregation. Specifically, the channel access method in the second embodiment of the present invention may include the following steps:

Step 301: The AP I listens to the channel, discovers and accesses the accessible channel.

Specifically, when the AP I listens to and selects an accessible channel, it can determine which channel(s) to access based on the channel quality and/or the situation in which its neighboring APs use the channel. The APs may have one or more neighboring APs, and the AP I may access one or more channels. The channel quality may be a parameter such as whether the channel is busy or duty cycle. The case where the neighboring AP uses the channel includes: whether the neighboring AP is a cooperative AP or the like.

For example: Before accessing the channel, AP I scans the monitored channel to find the n channels that are least busy, such as the first n channels with the lowest duty cycle. Then, AP 1 listens to its neighboring APs to determine whether the neighboring APs are potential cooperative APs. If yes, the channels currently accessed by each neighboring AP, such as channel a, channel b, channel i, and the like, may be obtained. Then, if it is judged that: the channel i accessed by a neighboring AP is the adjacent channel of the channel j (0<j < n) in the first n channels with the lowest duty ratio, the AP I can preferentially access the channel. j, Establish BSS (Basic Service Set).

Step 302: The AP 1 listens to each neighboring AP, and determines whether the neighboring AP is a cooperative AP that can cooperate with the channel. In this embodiment, the AP2 is used as the cooperative AP.

For example: AP I listens to the PPDU sent by the neighboring AP, and determines whether the AP2 is a cooperative AP. The method for determining whether AP2 is a cooperative AP is as follows:

Method 1: Determine according to the address information, where the address information may be a BSSID;

The AP I can obtain the BSSID of the neighboring AP2 by solving the MAC frame header, and determine whether the AP2 is a cooperative AP according to the B S SID.

The partial B S S ID of the physical layer may be added to identify the B S S ID of the AP2. The AP 1 may obtain the partial BSSID of the neighboring AP2 by decomposing the PPDU of the physical layer, and determine whether the AP2 is a cooperative AP according to the partial BSSID.

The partial BSSID is a function of the BSSID. FIG. 7 is a schematic diagram of a partial BSSID in the channel access method according to the embodiment of the present invention. As shown in FIG. 7, for example, 39-47 bits in the BSSID may be used as the partial BSSID, and the physical solution is solved. The PPDU of the layer can obtain the BSS ID information of the AP2. The AP 1 can obtain the BSSID information by parsing the PPDU of the physical layer, and does not need to parse the MAC, and can quickly find out whether the neighboring AP2 is a coordinated AP.

For example: If the BSSID of AP2 is in the preset cooperation set of AP I, AP2 is an AP that can cooperate with AP I.

Method 2, judge according to SSID;

For example: If the SSID of the neighboring AP is the same as the SSID of the AP I, and the ESS to which the SSID belongs supports cooperative transmission. Step 303: The AP (AS) performs interaction with the AP2 that can cooperate with the DS (Distribution System) to establish a cooperative relationship, establish a cooperative relationship of the shared channel, and negotiate to determine the cooperative transmission mode, such as determining to adopt JT. Any one of the cooperative transmission modes such as CS/CB, IA, and direct transmission may be different depending on the bandwidth used by AP I and AP2.

The bandwidth used by the AP 1 and the AP 2 may be the same or different. After the AP 1 establishes a cooperative relationship with the neighboring AP 2, the AP 1 and the AP 2 negotiate the coordinated transmission mode. At the same time, the specific coordinated transmission mode is adopted, and when the cooperative transmission is performed subsequently, the data transmission is performed according to the determined coordinated transmission mode. For example, FIG. 8 is a schematic diagram of distribution of an AP and a STA in a channel access method according to an embodiment of the present invention, as shown in FIG. 8. STA3, STA4, STA5, and STA6 are in the OBSS (Overlapping Basic Service Set) area of AP I and AP2, and STA1 and STA2 are in the exclusive areas of AP I and AP2, respectively.

After the AP I accesses the channel, through the establishment of the cooperative relationship, the AP I can utilize the channel currently accessed by the AP2. When AP2 uses the current access channel of AP I, there may be cases where other APs also use the channel currently accessed by AP 1, so that AP2 cannot use the channel currently accessed by AP I, or AP2 can only access 20 MHz for legacy stations. The case of bandwidth. This may result in inconsistent bandwidth available between AP 1 and AP2. According to the respective available bandwidth of AP I and AP2, AP I and AP2 can adopt the following cooperative transmission modes:

Case 1: AP I and AP2 use the same channel.

In this case, the available channel that AP I is currently accessing is available to AP2, and the cooperative available channel currently accessed by AP2 is also available to AP I. If the channels of the two APs are adjacent, and the guard intervals are also included between the channels, the guard intervals can also be used together. In this case, for STA3, STA4, STA5 and both in the OBSS area STA6, AP I and AP2 can adopt cooperative transmission methods such as JT, CS/CB and IA. For STA 1 and STA 2 in the non-OB SS area, AP 1 and AP 2 can adopt cooperative transmission methods such as CS/CB, IA, and traditional non-precoding direct transmission (does not generate mutual interference).

Case 2: AP I and AP2 use different channels.

In this case, the available channel of AP I's current access is not available to AP2, and the bandwidth used by the two APs is different. If the channels of the two APs are adjacent, the AP I can use the inter-channel guard interval and the cooperative access channel of the current access of the AP2, and the AP2 can only maintain the cooperative available channel originally accessed by the AP2. For STA3, STA4, STA5, and STA6 in the OBSS area, AP I and AP2 can adopt cooperative transmission modes such as CS/CB and IA. For STA 1 and STA2 in the non-OBSS area, AP I and AP2 can use CS/CB, IA, and traditional non-pre-coded direct transmission (no mutual interference).

Then, A P 1 can determine whether to share channel resources and how to share channel resources according to the NAV information of the channel on which the intercepted party competes for the right to use and the information of the channel that is competing for itself. Specifically, if the cooperatively APs compete for the N A V of the used channel to be greater than a certain threshold, A P 1 may mark the channel in which the cooperative AP competes to use the right as the transport channel. At this time, if the AP I also competes for the right to use the channel that it accesses, the AP I sends the information on the channel that the user is competing for the right to use and the channel of the cooperative AP; if the AP I does not compete for the self-connection For the right to use the incoming channel, AP 1 cooperates with the cooperative AP to use the cooperative AP to compete for the channel for obtaining the right to use. If the NAV of the cooperative AP is less than a certain threshold, the API will abandon the channel currently accessed by the cooperative AP during the transmission, and use the channel that it is currently accessing according to its own contention. Specifically, the method may include the following steps:

Step 304: The AP 1 competes for the channel in the channel it accesses, and simultaneously monitors the situation in which the AP2 competes for the channel. AP I can be based on the partial BSSID letter in the above PPDU. The information or the BSS ID information of the MAC frame header determines whether the PPDU is sent by the AP2. If yes, the NAV information of the AP2 is determined from the PPDU sent by the AP2.

Step 305: After the API monitors that the AP2 has obtained the channel usage right, it determines the channel currently used by the AP 2. If the N AV of the AP 2 is less than a certain threshold, step 306 is performed; if the NAV of the AP2 is greater than Or equal to or equal to a certain threshold, step 307 is performed.

Step 306: The API currently abandons the channel that the AP2 has obtained the usage right, and performs step 308. The channel acts as a cooperative available channel and is labeled as the transport channel of the API. Then, step 311 can be directly performed for data transmission, and step 309 can also be performed.

Step 308: The API determines, according to the information of the contention channel of the competition, whether the API obtains the right to use the current access channel. If the API obtains the right to use the current access channel, the current access channel is available for itself. Channel, the API will simultaneously mark the transmission channel of the transmission as the API. Then, step 311 can be performed for data transmission, or step 309 can be performed. Otherwise, step 308 is repeated after ending the process or continuing to compete for the channel.

In the embodiment of the present invention, there is no limitation on the timing of the API contention channel and the AP2 competition channel, and may be performed simultaneously or sequentially.

Step 309: The API determines whether the available channel of the available channel and the AP2 are adjacent channels. If yes, go to step 310, otherwise go to step 311.

Step 310: The API marks the guard interval between the available channel of itself and the cooperative available channel of AP2 as a transport channel.

The bandwidth of the guard interval between channels in the embodiment of the present invention is not specifically limited, and may be an integer multiple of 20 MHz or 20 MHz, or may be other values. For different applications, the guard interval may have different bandwidths. For example: IEEE 802.11 works on a bandwidth of 20Mhz, and a 40MHz bandwidth channel is introduced in 802.1 In. 802. 1 l ac introduces a 160MHz bandwidth consisting of a continuous 80MHz bandwidth and two non-contiguous 80MHz bandwidths. The combination is shown in Figure 9. FIG. 9 is a schematic diagram of different bandwidth combinations in a channel access method according to Embodiment 2 of the present invention. Whether in continuous 20MHz, 40MHz or 80MHz, the spectrum template is developed in the standard. The bandwidth of the guard interval needs to meet the requirements of the spectrum template. In the actual transmission process, in addition to meeting the spectrum template requirements in the standard, it is also necessary to meet the transmission power limits of various countries and regions to reduce the interference to other channels and communication systems.

The large bandwidth transmission mode in 802.1 I n and 802.1 1 ac can improve throughput and impose high requirements on spectrum opportunities. In the case of fewer APs or STAs or a better communication environment, APs or STAs based on the new standard may find a relatively high-speed continuous 40MHz or 80MHz spectrum for high-throughput transmission. However, in the case of a dense density of APs or STAs based on the new standard, or in the case of a legacy user who can only support 20 MHz bandwidth transmission, almost all idle available spectrum is occupied, based on the new standard. It is difficult for an AP or STA to find a thousand consecutive 40MHz or 80MHz spectrum, making the high-throughput performance of the new standard AP or STA difficult to reflect. At the same time, in the channel of the unlicensed frequency band, when the AP or STA accesses the channel, it will listen to whether the channels of the specified bandwidth are idle, so as to avoid collision collision. However, due to the low cost of the WiFi terminal, even if the regional transmission power limitation and the spectrum shielding requirement in the standard are met, the WiFi terminal will have a large amount of frequency dive leaking to the adjacent channel during the transmission. When the distance between the AP or the STA is relatively close, or the density of the network is large, these leaks are in a busy state, so that adjacent channels cannot be used even if the adjacent channel is actually idle. 10 is a schematic diagram of channel usage in a channel access method according to Embodiment 2 of the present invention. As shown in FIG. 10, if AP I and AP2 are relatively close, AP 1 is communicating on channel 1 12, and AP 2 is communicating on channel 120. Where channel 1 16 is equivalent Then the guard interval between the two. At this time, if the AP3 adjacent to them is listening to the CCA channel 116, since the AP I has the frequency sneak leak channel 116 on the channel 112 and the AP2 channel 120, it may result in the busy result of the channel 116. In fact, the channel 116 is idle, and the frequency transmission on the channel 112 and the channel 120 is leaked, causing the channel 116 to be unclean, resulting in waste of spectrum resources. The channel access method in the embodiment of the present invention can utilize the guard interval between channels to easily obtain large bandwidth transmission.

FIG. 11 is a schematic diagram of a guard interval used in a channel access method according to an embodiment of the present invention. As shown in FIG. 11, AP 1 establishes a BSS by competing to access the left available channel (channel 112). The AP2 that can cooperate with it is the right cooperative available channel (channel 120). If AP I's own available channel and AP2's cooperative available channel are adjacent available channels, and there is a guard interval between the two channels ( Channel 116), after performing step 313, the AP I may mark its own available channel, the cooperative available channel that AP2 is using, and the guard interval between the two channels as the transmission channel. Specifically, FIG. 12 is a schematic diagram of a NAV in a channel access method according to an embodiment of the present invention. As shown in FIG. 12, the AP I competes to obtain the right to use the channel 112, and finds that the AP2 occupying the channel 120 is adjacent thereto. Cooperating with the AP, and the AP2 competes for the right to use the channel 120, and the NAV value of the AP2 is relatively long. For example, the NAV value of the AP2 is greater than the NAV value of the AP1. If the guard interval between the channel 112 and the channel 120 is the channel 116, Then AP I can use channel 112, channel 1 16 and channel 120 as transport channels. If channel 112, channel 116, and channel 120 are separated by 20 MHz, AP 1 can transmit data over a bandwidth of 60 MHz.

Step 311: The AP 1 and the AP2 negotiate to start the coordinated transmission, and perform the data transmission on the marked transmission channel by using the cooperative transmission mode determined in the foregoing step 303.

For the cooperative transmission mode that needs to be synchronized, for example: JT mode, after AP I and AP2 negotiate the start time of the coordinated transmission, the two cooperate according to the previously negotiated coordinated transmission. Modes are transmitted on their respective transport channels. For cooperative transmission modes that do not require synchronization, such as: CS/CB, IA, and direct transmission, AP I transmits on the transmission channel according to the cooperative transmission mode negotiated with AP2 after determining the transmission channel.

In the channel access method of the embodiment of the present invention, in addition to using the self-available channel that the user has obtained the right to use, the AP may also use the cooperative cooperative channel of the neighboring cooperative AP to obtain the cooperative available channel for the use right, thereby improving spectrum utilization. rate.

In addition, when the cooperative available channel of the cooperative AP is adjacent to the AP's own available channel, the guard interval between the channels can be fully utilized, thereby further improving the spectrum utilization rate; thereby reducing network congestion and improving network performance.

Further, the partial BSSID parameter is introduced in the PPDU of the physical layer, and the AP only needs to parse the PPDU of the neighboring AP physical layer to quickly find out whether the neighboring cooperative AP has a channel.

Further, for different AP and STA location areas, the embodiment of the present invention can support multiple different coordinated transmission modes, and the AP and its cooperating APs can adopt different cooperative transmission modes according to different available bandwidths, which are effective. The spectrum utilization is improved, and the cooperation between different bandwidth APs is supported, the robustness of the system is enhanced, the interference is effectively suppressed, and the network throughput is increased.

Embodiment 3

FIG. 13 is a schematic structural diagram of an access device according to Embodiment 3 of the present invention. As shown in FIG. 13, the access device includes:

a cooperative device determining module 41, configured to determine another access device capable of using the channel with the cooperative as the cooperative access device;

The cooperative channel determining module 43 is configured to monitor a usage status of a channel accessed by the cooperative access device, and determine, in a channel used by the cooperative access device, a channel that can be used by the access device as a collaboration. Available channel;

a data transmission module 45, configured to transmit a signal including the cooperative available channel The channel performs data transmission.

Specifically, the access device may perform corresponding steps in the channel access method of the foregoing embodiment, and may refer to related descriptions in the foregoing embodiments.

In the embodiment of the present invention, after the access device cooperation device determining module 41 determines that the other access devices that can cooperate with the channel are determined as the cooperative access device, the cooperative channel determining module 43 monitors the usage status of the channel accessed by the cooperative access device. And determining, in the channel used by the cooperative access device, a channel that can be used by the access device as a cooperative available channel, and after marking the cooperative available channel as a transport channel, the data transmission module 45 can perform data transmission on the transport channel, so that A channel may access multiple access devices at the same time, which improves spectrum utilization and reduces network congestion.

Embodiment 4

FIG. 14 is a schematic structural diagram of an access device according to Embodiment 4 of the present invention, and components in FIG. 14 having the same reference numerals as those in FIG. 13 have the same functions. As shown in FIG. 14, the main difference between the access device and the access device shown in FIG. 13 is that, in one mode, the cooperative device determining module 41 of the access device may include:

The parsing sub-module 41 1 is configured to parse the physical layer convergence process protocol data unit PPDU and/or the media access control MAC frame header of the other access device, and obtain address information of the other access device, where the address information is Includes basic service set identifiers;

The first determining sub-module 413 is configured to determine the other access device as the cooperative access device if the address information is included in a cooperative access set of the access device.

In another mode, the collaboration device determining module 41 may further include: a monitoring submodule 415, configured to listen to obtain a service set identifier of the other access device;

a second determining submodule 417, configured to: if the service of the other access device is set And identifying, by the access device, the extended service set to which the service set identifier belongs to support coordinated transmission, and determining the other access device as the coordinated access device.

Further, the cooperative channel determining module 43 may be configured to: if the network access vector of the channel in which the cooperative access device competes for obtaining the usage right is greater than or equal to a set threshold, the cooperative access device is competitively obtained. The channel of the usage right is determined to be the cooperative available channel.

Further, the cooperative channel determining module 43 is further configured to: if the access device competes for obtaining the right to use the channel accessed by itself, the access device competes for obtaining the right to use itself The channel and the cooperative available channel are jointly determined as the transport channel.

Specifically, the cooperative channel determining module 43 may include:

The first transport channel determining sub-module 43 1 is configured to: if the self-available channel is adjacent to the cooperative available channel, use the self-available channel and the cooperative available channel together with a guard interval between the two The transmission channel;

a second transmission channel determining sub-module 433, configured to use the carrier aggregation mode and the cooperative available channel as a carrier channel if the self-available channel is not adjacent to the cooperative available channel. .

Additionally, the data transfer module 45 can include:

The cooperative transmission mode determining sub-module 45 1 is configured to negotiate with the cooperative access device to determine a cooperative transmission mode;

The data transmission sub-module 453 is configured to perform data transmission on the transmission channel by using the cooperative transmission mode.

The specific method for determining the cooperative transmission mode by the cooperative transmission mode determination sub-module can be divided into the following cases:

Case 1: If the access device and the cooperative access device use the same channel used for transmitting data, the site in the overlapping basic service set area is Any one of the joint transmission, CS/CB or interference-aligned cooperative transmission mode is adopted as the cooperative transmission mode; for sites outside the overlapping basic service set areas, CS/CB, interference alignment or direct transmission is adopted. Any one of the cooperative transmission modes as the cooperative transmission mode;

Case 2: If the access device and the cooperative access device use different channels for transmitting data, the CS/CB or the interference-aligned cooperative transmission mode is adopted for the sites in the overlapping basic service set areas. Any one of the cooperative transmission modes is adopted, and any one of the CS/CB, the interference alignment, or the direct transmission cooperative transmission mode is adopted as the cooperative transmission mode for the sites that are outside the overlapping basic service set regions.

In addition, the access device may further include:

The access module 5 1 is configured to determine, according to the monitored channel quality and/or the usage of the neighboring access devices, the channel accessed by the access device.

Further, the first transport channel determining sub-module 43 1 of the access device may also use its own available channel and the cooperative available channel as the transport channel, which may improve spectrum utilization; the second transport channel determining sub-module 433 may use its own available channel, The cooperative available channel and the guard interval between the two serve together as a transmission channel, which can form a continuous thousand-thousand frequency spectrum, realize large-bandwidth transmission, further improve spectrum utilization, and reduce network congestion. In addition, the cooperative transmission mode determining sub-module 451 adopts different coordinated transmission modes for different situations, which not only can effectively improve spectrum utilization, but also support cooperation between access devices with different bandwidths, thereby enhancing system robustness. Effectively suppresses interference and increases network throughput.

The channel access method and the access device according to the embodiment of the present invention are applicable to the field of wireless communication, and are particularly applicable to a scenario of a wireless local area network, wherein the wireless local area network may include: an access device and a station. Referring to Figure 8, AP I and AP2 are access devices, and STA 1 to STA6 are sites. The access device may adopt the specific structure of the access device in the foregoing embodiment. In the process of the downlink transmission of the access device to the station, the access device may use the channel access method in the foregoing embodiment, utilize the cooperative available channel of the cooperative access device, or simultaneously use the guard interval as the transmission channel and perform data transmission. A channel may access multiple access devices at the same time; thus, it can improve spectrum utilization and reduce network congestion.

Those of ordinary skill in the art will appreciate that the various exemplary units and algorithm steps in the embodiments described herein can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can select different methods for implementing the described functions for a particular application, but such implementation should not be considered to be beyond the scope of the present invention.

If the function is implemented in the form of computer software and sold or used as a stand-alone product, it is considered to some extent that all or part of the technical solution of the present invention (for example, a part contributing to the prior art) is It is embodied in the form of computer software products. The computer software product is typically stored in a computer readable storage medium, including thousands of instructions for causing a computer device (which may be a personal computer, server, or network device, etc.) to perform all or part of the steps of various embodiments of the present invention. . The foregoing storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM), and a random access memory. A medium that can store program code, such as a RAM (Random Access Memory), a disk, or an optical disk.

The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, and the invention may also be applied to a heterogeneous network of LTE-A, and any person skilled in the art may Variations or substitutions are readily conceivable within the scope of the present invention. Therefore, the scope of the invention should be determined by the scope of the claims.

Claims

claims

1. A channel access method, characterized by including:

The access device determines other access devices that can cooperate with it to use the channel as cooperative access devices;

The access device monitors the usage status of the channel accessed by the cooperative access device, and determines a channel that can be used by the access device among the channels used by the cooperative access device as a cooperative available channel; as well as

The access device performs data transmission on a transmission channel including the cooperative available channel.

2. The channel access method according to claim 1, characterized in that the access device determines other access devices that can cooperate with it to use the channel as cooperative access devices, including:

The access device parses the physical layer convergence process protocol data unit PPDU and/or the media access control MAC frame header of the other access device to obtain the address information of the other access device, where the address information includes basic services Set identifier; If the address information is included in the coordinated access set of the access device, the access device determines the other access device as the coordinated access device.

3. The channel access method according to claim 1, characterized in that the access device determines other access devices that can cooperate with it to use the channel as cooperative access devices, including:

The access device monitors and obtains the service set identifier of the other access device;

If the service set identifier of the other access device is the same as the access device and the extended service set to which the service set identifier belongs supports cooperative transmission, H'J determines the other access device as the cooperative transmission Access device.

4. The channel access method according to any one of claims 1 to 3, wherein the channel that can be used by the access device among the channels used by the cooperative access device is determined as Available channels for collaboration include:

If the network allocation vector of the channel for which the cooperative access device competes to obtain the right to use is greater than or equal to the set threshold, then the channel for which the cooperative access device competes to obtain the right to use is determined as the cooperative available channel.

5. The channel access method according to any one of claims 1 to 4, characterized in that, further comprising:

If the access device competes to obtain the right to use the channel that it accesses, then the own available channel and the cooperative available channel for which the access device competes to obtain the right to use are jointly determined as the transmission channel.

6. The channel access method according to claim 5, characterized in that, the self-available channel and the cooperative available channel for which the access device competes to obtain the right to use are jointly determined as the transmission channel, include:

If the self-available channel is adjacent to the cooperative available channel, then the self-available channel, the cooperative available channel and the guard interval between the two are jointly used as the transmission channel;

If the self-available channel and the cooperative available channel are not adjacent, the self-available channel and the cooperative available channel are used as the transmission channels in a carrier aggregation manner.

7. The channel access method according to any one of claims 1 to 6, characterized in that the access device performing data transmission on the transmission channel including the cooperative available channel includes:

The access device adopts a cooperative transmission mode determined through negotiation with the cooperative access device to transmit data on the transmission channel.

8. The channel access method according to claim 7, characterized in that the access device adopts a cooperative transmission method determined through negotiation with the cooperative access device. Formula, data transmission is performed on the transmission channel, including:

If the channel used by the access device and the cooperative access device to transmit data is the same, then for the stations in the overlapping basic service set area of the two, joint transmission, collaborative scheduling CS/collaborative beamforming CB or Any one of the interference-aligned cooperative transmission methods, perform data transmission on the transmission channel; for stations outside the overlapping basic service set area, use any of the CS/CB or interference-aligned or direct transmission cooperative transmission methods. One is to perform data transmission on the transmission channel. If the channels used by the access device and the cooperative access device to transmit data are different, then CS/CB is used for stations located in the overlapping basic service set area of the two. Or any one of the interference-aligned cooperative transmission methods, data transmission is performed on the transmission channel; for stations outside the overlapping basic service set area, CS/CB, interference-aligned or direct transmission cooperative transmission methods are used Any one of them, perform data transmission on the transmission channel.

9. The channel access method according to any one of claims 1 to 8, characterized in that, before the access device determines other access devices that can cooperate with it to use the channel as cooperative access devices, it includes:

The channel accessed by the access device is determined based on the monitored channel quality and/or the usage of the other adjacent access devices.

10. An access device, characterized by: including:

A cooperative device determination module, configured to determine other access devices that can cooperate with it to use the channel as cooperative access devices;

A cooperative channel determination module, configured to monitor the usage status of the channels accessed by the cooperative access device, and determine the channels that can be used by the access device among the channels used by the cooperative access device as available for cooperation. channel; and

A data transmission module, configured to transmit data on a transmission channel including the cooperative available channel.

11. The access device according to claim 10, characterized in that the cooperative device determination module includes:

The parsing submodule is used to parse the physical layer convergence process protocol data unit PPDU and/or the media access control MAC frame header of the other access device to obtain the address information of the other access device, where the address information includes basic Service set identification payment;

The first determination submodule is configured to determine the other access device as the coordinated access device if the address information is included in the coordinated access set of the access device.

12. The access device according to claim 10, characterized in that the cooperative device determination module includes:

The listening submodule is used to monitor and obtain the service set identifier of the other access device;

The second determination submodule is configured to, if the service set identifier of the other access device is the same as the access device and the extended service set to which the service set identifier belongs supports coordinated transmission, then determine the other access device. The device is determined to be the cooperative access device.

13. The access device according to any one of claims 10 to 12, characterized in that the cooperative channel determination module is configured to: if the cooperative access device competes for the network allocation of the channel that has obtained the right to use it If the vector is greater than or equal to the set threshold, the channel for which the cooperative access device competes to obtain the right to use is determined to be the cooperative available channel.

14. The access device according to any one of claims 10-13, characterized in that the cooperation channel determination module is also used to:

15. The access device according to any one of claims 14, characterized in that the cooperation channel determination module includes:

The first transmission channel determination submodule is configured to, if the self-available channel is adjacent to the cooperative available channel, use the self-available channel, the cooperative available channel and the guard interval between them as the transmission channel;

The second transmission channel determination submodule is configured to use carrier aggregation as the transmission channel if the self-available channel and the cooperative available channel are not adjacent.

16. The access device according to any one of claims 10 to 15, characterized in that the data transmission module includes:

The cooperative transmission mode determination submodule is used to negotiate with the cooperative access device to determine the cooperative transmission mode;

The data transmission submodule is configured to use the cooperative transmission method to transmit data on the transmission channel.

17. The access device according to claim 16, characterized in that the cooperative transmission mode determination sub-module is specifically used to:

If the channel used by the access device and the cooperative access device to transmit data is the same, then for the stations located in the overlapping basic service set area of the two, the joint transmission, CS/CB or interference-aligned cooperative transmission method is used. Any one of the cooperative transmission methods is used as the cooperative transmission method; for stations outside the overlapping basic service set area, any one of CS/CB, interference alignment or direct transmission cooperative transmission methods is used as the cooperative transmission method;

If the channels used by the access device and the cooperative access device to transmit data are different, then any one of the CS/CB or interference-aligned cooperative transmission methods is used for stations located in the overlapping basic service set area of the two. as the cooperative transmission method; for stations outside the overlapping basic service set area, any one of CS/CB, interference alignment or direct transmission cooperative transmission methods is used as the cooperative transmission method. The cooperative transmission method.

18. The access device according to any one of claims 10 to 17, further comprising:

The access module is configured to determine the channel accessed by the access device based on the monitored channel quality and/or the usage of the other adjacent access devices.