CN115484609A

CN115484609A - Data transmission method, device and system and computer readable storage medium

Info

Publication number: CN115484609A
Application number: CN202110666467.XA
Authority: CN
Inventors: 王云贵
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-06-16
Filing date: 2021-06-16
Publication date: 2022-12-16

Abstract

Disclosed are a data transmission method, device and system, and a computer readable storage medium, belonging to the technical field of wireless communication. A first AP receives an RTS frame from a STA associated with the first AP. The first AP sends a CTS frame to the STAs on the first channel group while sending a collaborative announcement frame on the second channel group. The CTS frame includes an indication of a first transmission duration, and the collaborative announcement frame includes an identification of the second AP, an indication of the first target channel group, and an indication of the first transmission duration. The cooperative announcement frame is used for indicating the second AP to use the first target channel group within a first transmission duration after receiving the cooperative announcement frame. In the uplink transmission process of the STA competing for the channel, other APs deployed at the same frequency with the AP associated with the STA can perform downlink transmission by using the unused channel bandwidth of the STA, so that uplink and downlink cooperative transmission of the STA and the non-associated AP is realized.

Description

Data transmission method, device and system and computer readable storage medium

Technical Field

The present application relates to the field of wireless communications technologies, and in particular, to a data transmission method, apparatus and system, and a computer-readable storage medium.

Background

A Wireless Local Area Network (WLAN) includes an Access Point (AP) and a Station (STA). The AP is used to provide bridging functionality between the WLAN and other types of networks, such as wired networks. The STA is assigned a wireless terminal, such as a smart phone, a notebook computer, and the like, which is configured with a WLAN access function.

Currently, the STA usually uses a carrier sense multiple access with collision avoidance (CSMA/CA) method to send uplink data to the AP. In addition, in the uplink transmission process, in order to avoid the problem of co-channel interference, under the scene of co-channel deployment of multiple APs, only the STA competing for the channel and the AP associated with the STA can transmit data, and the flexibility of data transmission is low.

Disclosure of Invention

The application provides a data transmission method, a data transmission device, a data transmission system and a computer readable storage medium, which can solve the problem of low data transmission flexibility at present.

In a first aspect, a data transmission method is provided. The method comprises the following steps: a first AP receives a Request To Send (RTS) frame from a STA associated with the first AP. The first AP sends a Clear To Send (CTS) frame to the STA on the first channel group in response to the RTS frame, while sending a coordination announcement (CoA) frame on the second channel group. The CTS frame includes an indication of a first transmission duration, and the collaborative announcement frame includes an identification of a second AP, an indication of a first target channel group, and an indication of a first transmission duration. The cooperative announcement frame is used for indicating the second AP to use the first target channel group within a first transmission duration after receiving the cooperative announcement frame. The working channel of the second AP overlaps with the working channel of the first AP, that is, the second AP and the first AP are deployed at the same frequency. The first channel group belongs to the operating channel of the first AP and includes a primary channel of the operating channel of the first AP. The second channel group includes one or more channels of the operating channels of the first AP other than the channels in the first channel group. The first target channel group belongs to and includes a primary channel of the second AP's operating channel, and the first target channel group does not include any channel in the first channel group.

In the application, after an STA contending for a channel sends an RTS frame to an AP associated with the STA, the AP associated with the STA may allocate a channel other than a channel used by the STA to other APs deployed at the same frequency as the AP, so that the other APs allocated to the channel can send a downlink frame to the STA associated with the STA on the allocated channel in a process that the STA sends an uplink frame to the AP associated with the STA, thereby implementing uplink and downlink cooperative transmission between the STA and a non-associated AP, improving flexibility of data transmission, and improving utilization rate of bandwidth resources.

Optionally, the primary channel of the operating channel of the second AP does not overlap with the primary channel of the operating channel of the first AP.

Optionally, the RTS frame comprises an indication of a second transmission duration.

In one implementation, the first AP receives an RTS frame from the STA on a third channel group that includes the first channel group and that includes channels of the operating channels of the first AP that are not in the first channel group. That is, the STA requests use of the third channel group for the second transmission duration, and the first AP permits the STA to use a part of the channels (i.e., the first channel group) of the third channel group for the first transmission duration.

Optionally, in this implementation, the first transmission duration is greater than or equal to the second transmission duration. Since the channel bandwidth of the third channel group requested to be used by the STA is smaller than the channel bandwidth of the first channel group permitted by the first AP to be used by the STA, the duration that the STA sends the uplink frame included in the first transmission duration set by the first AP is longer than the duration that the STA sends the uplink frame included in the second transmission duration set by the STA, and thus the first transmission duration may be longer than or equal to the second transmission duration.

In another implementation, a first AP receives RTS frames from STAs on a first channel group. That is, the STA requests use of the first channel group for the second transmission duration, and the first AP grants the STA use of the first channel group for the first transmission duration. In this implementation, the first transmission duration is less than the second transmission duration.

Optionally, the first transmission duration is greater than a duration threshold.

In this application, since the first transmission duration includes the transmission time of the collaborative announcement frame and the time for the second AP to parse the collaborative announcement frame, if the first transmission duration is too small, the second AP may not be able to send a downlink frame within the first transmission duration of the received collaborative announcement frame or may not be able to send a downlink frame until the second AP finishes sending a downlink frame, which means that collaborative transmission cannot be achieved. Therefore, by setting the first transmission duration to be greater than the duration threshold, the reliability and the effectiveness of the cooperative transmission can be improved.

Optionally, the start time and the end time of the CTS frame transmitted by the first AP are the same as the start time and the end time of the coordinated announcement frame, respectively, and the CTS frame includes a padding field.

In the present application, the length of the CTS frame is equal to the length of the cooperative announcement frame by adding the padding field to the CTS frame, and further, the start time and the end time for the first AP to transmit the CTS frame are respectively the same as the start time and the end time for transmitting the cooperative announcement frame. Synchronous transmission of the CTS frame and the cooperative announcement frame can be realized, and synchronous response of the STA to the CTS frame and synchronous response of other APs receiving the cooperative announcement frame to the cooperative announcement frame are further realized, so that the reliability of cooperative transmission is improved.

Optionally, the collaborative announcement frame further includes an identification of a third AP, an indication of a second target channel group, and an indication of the first transmission duration. The cooperative announcement frame is further configured to instruct the third AP to use the second target channel group within the first transmission duration after receiving the cooperative announcement frame. Wherein the working channel of the third AP overlaps with the working channel of the first AP. The second target channel group belongs to and includes a primary channel of the operating channel of the third AP, and the second target channel group does not include the first channel group and any channel of the first target channel group.

Optionally, the first AP may also receive frames from the STAs on the first channel group. The frame may be a data frame, a control frame, or a management frame.

In a second aspect, a data transmission method is provided. The method comprises the following steps: the AP receives a preamble of a first frame from a STA that is not associated with the AP, the preamble of the first frame including an indication of a transmission duration of a data portion of the first frame. And when the main channel of the working channel of the AP is idle, the AP sends a second frame to the STA associated with the AP on the main channel of the working channel of the AP within the sending duration after receiving the lead code of the first frame.

In the application, when an STA competing for a channel sends an uplink frame to an AP associated with the STA, other APs deployed at the same frequency as the AP associated with the STA may monitor the uplink frame on a working channel, and send a downlink frame to the STA associated with the STA on a main channel when the main channel is idle, that is, other APs deployed at the same frequency as the AP associated with the STA competing for the channel may actively initiate cooperative transmission to perform downlink transmission by using a channel bandwidth unused by the STA, thereby implementing uplink and downlink cooperative transmission between the STA and a non-associated AP, improving the flexibility of data transmission, and also improving the utilization rate of bandwidth resources.

Optionally, when there is an idle secondary channel in the working channel of the AP, the AP may further send a second frame to the STA associated with the AP on the idle secondary channel within the sending duration after receiving the preamble of the first frame. That is, the AP may transmit the second frame to the STA associated with the AP using the total bandwidth of the primary channel and the idle secondary channel.

In the application, the AP sends the second frame to the STA associated with the AP by using the total bandwidth of the primary channel and the idle secondary channel, so that on one hand, the bandwidth resources can be fully utilized, and the utilization rate of the bandwidth resources is improved. On the other hand, the transmission time of the second frame can be reduced, so that the AP can transmit more data to the STA associated with the AP within a specified time duration, thereby improving the transmission efficiency.

Optionally, an implementation manner in which the AP sends the second frame to the STA associated with the AP on the primary channel of the working channel of the AP includes: and when the sending duration is greater than the duration threshold, the AP sends a second frame to the STA associated with the AP on the main channel of the working channel of the AP.

In the application, because the AP may send the downlink frame after analyzing the preamble after receiving the preamble of the first frame and after a Short Inter Frame Space (SIFS) is completed, if the sending duration of the data portion of the first frame is too small, the AP may not be in time to send the downlink frame in the sending duration or may not be in time to send one downlink frame, that is, cooperative transmission cannot be achieved. Therefore, by setting the condition that the sending duration of the data part of the first frame is greater than the duration threshold as the condition that the AP sends the second frame to the STA associated with the AP, the reliability and the effectiveness of cooperative transmission can be improved.

In a third aspect, an AP is provided. The AP comprises a plurality of functional modules, which interact to implement the method in the first aspect and its embodiments. The functional modules can be implemented based on software, hardware or a combination of software and hardware, and the functional modules can be arbitrarily combined or divided based on specific implementations.

In a fourth aspect, an AP is provided. The AP comprises a plurality of functional modules that interact to implement the method in the second aspect and its embodiments described above. The functional modules can be implemented based on software, hardware or a combination of software and hardware, and the functional modules can be combined or divided arbitrarily based on specific implementation.

In a fifth aspect, a data transmission system is provided, which includes: a STA, a first AP and a second AP, wherein the working channels of the first AP and the second AP overlap, the STA is associated with the first AP, and the first AP is configured to perform the method according to any one of the first aspect, or the second AP is configured to perform the method according to any one of the second aspect.

In a sixth aspect, an AP is provided, including: a transceiver and an antenna;

the transceiver is configured to perform transceiving actions on an operating channel of the AP using the antenna, and to implement the method in the first aspect and the embodiments thereof or to implement the method in the second aspect and the embodiments thereof.

In a seventh aspect, a computer-readable storage medium is provided, which has instructions stored thereon, which when executed by a processor of a computer device, implement the method of the first aspect and its embodiments or implement the method of the second aspect and its embodiments.

In an eighth aspect, a chip is provided, which comprises programmable logic circuits and/or program instructions, and when the chip is run, implements the method of the first aspect and its embodiments or implements the method of the second aspect and its embodiments.

Drawings

Fig. 1 is a schematic diagram of a multi-AP coordination architecture according to an embodiment of the present disclosure;

fig. 2 is a schematic view of an application scenario involved in a data transmission method provided in an embodiment of the present application;

fig. 3 is a schematic flowchart of a data transmission method according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a collaborative announcement frame according to an embodiment of the present application;

fig. 5 is a schematic diagram of a frame transmission sequence according to an embodiment of the present application;

fig. 6 is a schematic diagram of another frame transmission sequence provided in the embodiment of the present application;

fig. 7 is a schematic flowchart of another data transmission method provided in an embodiment of the present application;

fig. 8 is a schematic diagram of another frame transmission sequence provided in an embodiment of the present application;

fig. 9 is a schematic structural diagram of a first AP according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of an AP according to an embodiment of the present application;

fig. 11 is a block diagram of an AP according to an embodiment of the present application.

Detailed Description

To make the objects, technical solutions and advantages of the present application more clear, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

The Institute of Electrical and Electronics Engineers (IEEE) 802.11 series of standards, also known as WLAN protocols, use a range of radio frequencies including the 2.4 gigahertz (GHz) band and the 5GHz band. Wherein, the 2.4GHz frequency band comprises 2.4GHz to 2.4835GHz, and the 5GHz frequency band comprises 5.150GHz to 5.350GHz and 5.725GHz to 5.850GHz. In order to avoid the co-channel interference problem, the available frequency bands in the WLAN are divided into independent channels, i.e. there is no frequency band overlap between the channels. For example, there are 3 independent channels in the 2.4GHz band, including channel 1, channel 6, and channel 11, so that at most three inter-frequency WLANs can be deployed simultaneously in the 2.4GHz band. In the embodiment of the present application, "x" in "channel x" refers to a channel number defined in the WLAN protocol. For example, the 5GHz band includes channel 36, channel 40, channel 44, channel 48, and so on.

Due to the limited signal coverage of a single AP, multiple APs are typically deployed to meet signal coverage requirements in high-density deployment scenarios such as offices, dining halls, airports, and train stations. Because the number of independent channels in the WLAN is limited, it cannot be satisfied that all APs perform inter-frequency deployment (i.e., each AP employs an independent channel), and therefore, some APs need to perform co-frequency deployment. The co-frequency deployment of multiple APs means that the working channels of the multiple APs overlap, specifically, the working channels of the multiple APs are completely the same, or the working channels of the multiple APs are partially the same.

In the embodiment of the present application, the operating channel of the AP refers to a complete WLAN channel, for example, a20 megahertz (MHz) WLAN channel, or a WLAN channel with a larger bandwidth (for example, 40mhz,80mhz or 160 MHz). A channel with a bandwidth greater than 20MHz may be referred to as a large bandwidth channel, which consists of multiple contiguous 20MHz channels. For example, in the 5GHz band, a 40MHz wide bandwidth channel may consist of 20MHz channel 36 and 20MHz channel 40, denoted as channel <36,40>. If the operating channel of the AP is a large bandwidth channel, the operating channel of the AP may include a primary channel and a secondary channel. Any 20MHz channel in the working channels of the AP may be set as a main channel, and there may be one or more main channels. The channels other than the primary channel in the working channels of the AP are secondary channels. To improve the quality of WLAN service, the AP may use a large bandwidth channel as an operating channel, such as a WLAN channel with a bandwidth of 40MHz or more. If the operating channel of the AP or STA is configured as a large bandwidth channel, a part or the entire bandwidth of the operating channel may be used for transmission each time data is transmitted, but at least one primary channel must be included. For example, if the operating channel of the AP is configured as an 80MHz channel <36,40,44,48>, wherein the primary channel is channel 36, then the AP may transmit data on the entire 80MHz channel, or on a 40MHz channel <36,40>, or on a20 MHz channel 36.

Current WLAN protocols only support single AP transmission without coordinated spatial multiplexing between different APs, and thus are limited in the efficient use of time, frequency and spatial resources. In order to effectively utilize limited wireless resources, the next generation WLAN protocol (IEEE 802.11be protocol) draft has started to introduce a multi-AP cooperative transmission technology. The multi-AP cooperative transmission refers to that multiple APs deployed at the same frequency transmit data together. Data information and control information are shared among the multiple APs through a wired network or a wireless network, and multi-AP cooperative transmission can be achieved, so that peak throughput is improved, spectrum utilization rate is improved, and transmission delay is reduced.

For example, fig. 1 is a schematic diagram of a multi-AP coordination architecture provided in the embodiment of the present application. As shown in fig. 1, a plurality of APs located at similar positions and deployed at the same frequency form a multi-AP cooperation group (as shown by the dashed box). The APs in the multi-AP cooperation group exchange data information and control information with each other through a wired network or a wireless network. There is a master AP (also called a sharing AP or coordinator AP) in the multi-AP cooperation group for controlling CSMA/CA channel access of each AP in the multi-AP cooperation group, scheduling frequency resources of each AP in the multi-AP cooperation group, coordinating cooperative transmission of multiple APs in the multi-AP cooperation group, and the like. The other APs in the multi-AP cooperative group except the primary AP are secondary APs (the secondary APs may also be referred to as shared APs or coordinated APs), and the secondary APs perform cooperative transmission according to the frequency resources allocated by the primary AP, subject to the scheduling of the primary AP. In a multi-AP cooperative architecture, the master AP is not fixed. Generally, an AP that preempts a channel in the multi-AP coordination group and performs data transmission within this transmission opportunity (TXOP) time is used as a primary AP, and other APs are used as secondary APs.

For example, in the multi-AP cooperative architecture shown in fig. 1, the operating channels of both AP 101A and AP 101B include channel 36 and channel 40. If the AP 101A preempts the channel this time, the AP 101A serves as a primary AP in the TXOP time, and can transmit downlink data to the STA 102A associated with the AP 101A; the AP 101B acts as a secondary AP during the TXOP time, subject to the scheduling of the AP 101A. If the AP 101B seizes the channel next time, the AP 101B serves as a master AP in the next TXOP time, and can transmit downlink data to the STA 102B associated with the AP 101B; the AP 101A acts as a secondary AP during the TXOP time, subject to the scheduling of the AP 101A.

The embodiment of the application provides a cooperative transmission mechanism triggered by an AP during uplink transmission aiming at a multi-AP co-frequency deployment scene. The method and the device for realizing the uplink and downlink cooperative transmission of the STA and the non-associated AP have the advantages that in the process that the STA competes to a channel for uplink transmission, other APs which are deployed at the same frequency with the AP associated with the STA can utilize unused channel bandwidth of the STA for downlink transmission, so that uplink and downlink cooperative transmission of the STA and the non-associated AP is realized, the flexibility of data transmission is improved, and the utilization rate of bandwidth resources is improved.

For example, fig. 2 is a schematic view of an application scenario involved in a data transmission method provided in an embodiment of the present application. As shown in fig. 2, the application scenario includes: a plurality of APs 201A-201C (collectively referred to as APs 201) and a plurality of STAs 202A-202C (collectively referred to as STAs 202). STA202A associates with AP201A, STA 202B associates with AP 201B, and STA 202C associates with AP201C. That is, the AP201A is configured to provide the STA202A with the wireless access service based on the WLAN protocol, the AP 201B is configured to provide the STA 202B with the wireless access service based on the WLAN protocol, and the AP201C is configured to provide the STA 202C with the wireless access service based on the WLAN protocol. The number of APs and STAs in the figure is only used as an exemplary illustration, and is not used as a limitation to an application scenario related to the data transmission method provided by the embodiment of the present application.

The AP201 is a network device having a WLAN chip or a WLAN system on a chip (SoC) chip. For example, AP201 may be a router or a switch, etc. The STA202 is a wireless terminal having a WLAN chip, for example, the STA202 may be a smart phone, a laptop, or a smart wearable device.

In the embodiment of the present application, the working channel of the AP201 and the main channel of the working channel are both configured in advance. The operating channels of AP201A, AP 201B, and AP201C overlap, and the main channels of the operating channels of AP201A, AP 201B, and AP201C do not completely overlap. For example, the operating channels of AP201A and AP 201B are the same, both 80MHz channels <36,40,44,48>. The operating channels of AP201A and AP201C partially overlap, and the operating channel of AP201C is a 40MHz channel <44,48>. The main channels of the working channels of the two APs are not completely overlapped, which means that the main channels of the working channels of the two APs are not overlapped at all or partially overlapped. For example, there are two main channels of the working channel of AP201A, including channel 36 and channel 40; the main channel of the working channel of the AP 201B is channel 40; the primary channel of the operating channel of AP201C is channel 44.

Optionally, the AP201 stores a neighbor AP list. The neighbor AP list records the primary channel of the working channel of the neighbor AP of AP 201. The neighbor AP list may further record identifiers of neighbor APs of the AP201, a working channel, and other information such as a Received Signal Strength Indication (RSSI) of the AP201 to the neighbor APs. The identity of the neighbor AP may be a Basic Service Set Identifier (BSSID) of the neighbor AP. The BSSID of the AP refers to a Medium Access Control (MAC) address of the AP at an air interface. One AP may use the working channel overlapping with the working channel of the AP, and use other APs with RSSI values greater than the threshold as neighbor APs of the AP. For example, if the neighbor APs of AP201A include AP 201B and AP201C, AP201A may store the neighbor AP list as shown in table 1.

TABLE 1

Identification of neighbor AP	Working channel	Main channel	RSSI
				BSSID1(AP 201B)	Channel with a plurality of channels<36,40,44,48>	Channel 40	RSSI1
BSSID2(AP 201C)	Channel with a plurality of channels<44,48>	Channel 44	RSSI2

Wherein BSSID1 is BSSID of AP 201B, and RSSI1 is RSSI value of AP201A to AP 201B. BSSID2 is the BSSID of AP201C, and RSSI2 is the RSSI value of AP201A for AP201C.

In some implementations, the neighbor AP list may be obtained by the AP by way of background channel scanning. When the AP is configured as an operating channel with a bandwidth of 20MHz, the AP listens to beacon (beacon) frames of other APs on the current operating channel, and if the AP can listen, the AP that transmits the beacon frame is taken as a neighbor AP and records the information of the neighbor AP in a neighbor AP list. When the AP is configured as an operating channel with a bandwidth of 40MHz or more, the AP selects each 20MHz channel of the set according to the 20MHz channel set included in the current operating channel, switches to the 20MHz channel for a period of time (e.g., 200 milliseconds), then listens to the beacon frames of other APs on the 20MHz channel, and if the beacon frames can be listened to, takes the AP that transmits the beacon frame as a neighbor AP and records the information of the neighbor AP in a neighbor AP list.

Optionally, the beacon frame sent by the AP carries an indication of the working channel of the AP and/or an indication of the main channel of the working channel of the AP, so that other APs that receive the beacon frame can record channel information of the AP. Alternatively, after determining the neighbor AP, the AP may send an indication of the operating channel of the AP and/or an indication of the main channel of the operating channel of the AP to the neighbor AP in a wired or wireless manner.

In other implementations, the neighbor AP list may be manually configured. Optionally, with continued reference to fig. 2, the application scenario further includes a wireless controller 203. The radio controller 203 may be an access controller. For example, the wireless controller 203 may specifically be an access device such as a switch or a gateway. The plurality of APs 201 are wired to the wireless controller 203. The wireless controller 203 is for managing the AP 201. The maintenance personnel can configure the neighbor AP list in the AP201 through the wireless controller 203.

Optionally, the AP may also receive and store service information sent by the neighbor AP, and may also send its own service information to the neighbor AP. The service information includes one or more of the data volume to be transmitted, the time length to be transmitted, the service priority of the data to be transmitted, or the user priority of the data to be transmitted. Due to the overlapping of the working channels of the AP and the neighbor AP, traffic information can be (wirelessly) synchronized between the AP and the neighbor AP on the working channel. Alternatively, the AP and the neighboring AP may synchronize service information through a wireless controller (wired).

In the embodiment of the application, the AP associated with the STA competing for the channel in the uplink transmission process is used as the primary AP, and the neighbor AP of the primary AP is used as the secondary AP. For example, in the application scenario shown in fig. 2, the STA 103A contends for the channel, and the AP103A is a primary AP, and the AP 103B and the AP 103C are both secondary APs.

Based on the same gist of the present application, the present application provides two implementation manners through the following two embodiments. In a first embodiment of the present application, a primary AP triggers a secondary AP to perform downlink transmission cooperatively in an uplink transmission process of an STA associated with the primary AP. In the second embodiment of the present application, the secondary AP actively performs downlink transmission in coordination during the uplink transmission of the STA associated with the primary AP.

The first embodiment of the present application: fig. 3 is a flowchart illustrating a data transmission method according to an embodiment of the present application. The method may be applied in an application scenario as shown in fig. 2. As shown in fig. 3, the method includes:

step 301, the first AP receives an RTS frame from a STA associated with the first AP.

The first AP is a master AP. And after the STA associated with the first AP competes for the channel, sending an RTS frame to the first AP. The RTS frame includes an indication of a second transmission duration. The other STAs remain silent for a second transmission duration after receiving the RTS frame. The RTS frame is used to request that the channel transmitting the RTS frame be occupied for the second transmission duration. The second transmission time period is a Network Allocation Vector (NAV) time period set by the STA, and includes a total duration from a start time when the STA transmits the RTS frame to an end time when the STA transmits the uplink frame. The indication of the second transmission duration may be carried in a duration (duration) field of the RTS frame. The uplink frame sent by the STA in this embodiment may be a data frame.

Step 302, the first AP sends a CTS frame to the STA in response to the RTS frame on the first channel group, and sends a cooperation announcement frame on the second channel group.

The first AP may send the CTS frame to the STA on the first channel group and send the cooperative announcement frame (CoA frame) on the second channel group after receiving a SIFS of the RTS frame from the STA, that is, the start time of the CTS frame transmitted by the first AP is the same as the start time of the cooperative announcement frame. The first AP may simultaneously transmit the CTS frame and the collaborative announcement frame on different channel groups using an orthogonal frequency division multiple access (orthogonal frequency division multiple access) technique.

Optionally, the start time and the end time of the CTS frame transmitted by the first AP are the same as the start time and the end time of the coordinated announcement frame, respectively, and the CTS frame includes a padding field. Since the length of the CTS frame is generally smaller than that of the cooperative announcement frame, a padding field may be added to the CTS frame so that the length of the CTS frame is equal to that of the cooperative announcement frame.

In the embodiment of the application, the length of the CTS frame is equal to the length of the cooperative announcement frame by adding the padding field in the CTS frame, and further, the start time and the end time for the first AP to transmit the CTS frame are respectively the same as the start time and the end time for transmitting the cooperative announcement frame. Synchronous transmission of the CTS frame and the cooperative announcement frame can be realized, and synchronous response of the STA to the CTS frame and synchronous response of other APs receiving the cooperative announcement frame to the cooperative announcement frame are further realized, so that the reliability of cooperative transmission is improved.

Alternatively, in other implementations, the length of the CTS frame may be greater than the length of the cooperative announcement frame, and then a padding field may be set in the cooperative announcement frame so that the length of the cooperative announcement frame is equal to the length of the CTS frame. The embodiments of the present application do not exclude this possibility.

The CTS frame includes an indication of a first transmission duration. The CTS frame transmitted on the primary channel group may be used to indicate that the STA is permitted to use the primary channel group for a first transmission duration after receiving the CTS frame. The first transmission duration is a NAV duration set by the first AP, and includes a total duration from a start time when the first AP transmits the CTS frame to an end time when the STA transmits the uplink frame. The indication of the first transmission duration may be carried in a duration field of the CTS frame.

In one implementation, a first AP receives an RTS frame from a STA on a first channel group. That is, the STA requests use of the first channel group for the second transmission duration, and the first AP grants the STA use of the first channel group for the first transmission duration. Wherein the first transmission duration is less than the second transmission duration.

In this implementation, since the channel group (first channel group) requested to be used by the STA is the same as the channel group (first channel group) permitted by the first AP to be used by the STA, the duration for the STA to transmit the uplink frame included in the first transmission duration set by the first AP is the same as the duration for the STA to transmit the uplink frame included in the second transmission duration set by the STA. For example, the first transmission duration may be equal to the second transmission duration minus the response duration of the first AP to the RTS frame (i.e., the transmission duration of the RTS frame) and 1 SIFS duration.

In another implementation, the first AP receives an RTS frame from the STA on a third channel group. The third channel group includes the first channel group and includes channels of the operating channels of the first AP that are not in the first channel group, i.e., the first channel group is a proper subset of the third channel group. That is, the STA requests to use the third channel group for the second transmission duration, and the first AP grants the STA to use a part of the channels in the third channel group (i.e., the first channel group) for the first transmission duration.

In this implementation, since the channel bandwidth of the third channel group requested to be used by the STA is smaller than the channel bandwidth of the first channel group permitted to be used by the STA by the first AP, the duration for the STA to send the uplink frame included in the first transmission duration set by the first AP is greater than the duration for the STA to send the uplink frame included in the second transmission duration set by the STA. For example, if the first channel group includes 1 channel and the third channel group includes 2 channels, the duration that the STA included in the first transmission duration set by the first AP transmits the uplink frame may be 2 times the duration that the STA included in the second transmission duration set by the STA transmits the uplink frame. In such implementations, the first transmission duration may be greater than or equal to the second transmission duration.

The collaborative announcement frame includes an identification of the second AP, an indication of the first target channel group, and an indication of the first transmission duration. The cooperative announcement frame is used for indicating the second AP to use the first target channel group within a first transmission duration after receiving the cooperative announcement frame. In this embodiment, the second AP is a secondary AP of the first AP.

Optionally, the identification of the second AP is a BSSID of the second AP. The indication of the first target channel group includes a channel coding of the channels included in the first target channel group. Optionally, the indication of the first target channel group further includes a channel bandwidth allocated to the second AP.

The following embodiments of the present application explain a relationship between the first channel group, the second channel group, the first target channel group, the working channel of the first AP, and the working channel of the second AP.

1. A relationship between the operating channel of the first AP and the operating channel of the second AP.

The operating channel of the first AP is a large bandwidth channel. The working channel of the second AP overlaps with the working channel of the first AP, and the main channel of the working channel of the second AP does not completely overlap with the main channel of the working channel of the first AP. For example, the first AP is AP201A in the application scenario shown in fig. 2, and the second AP is AP 201B in the application scenario shown in fig. 2. The operating channels of AP201A and AP 201B are the same, both 80MHz channels <36,40,44,48>. The main channel of the working channel of the AP201A includes the channel 36 and the channel 40, and the main channel of the working channel of the AP 201B is the channel 40.

Optionally, the primary channel of the operating channel of the second AP does not overlap with the primary channel of the operating channel of the first AP. For example, the first AP is AP201A in the application scenario shown in fig. 2, and the second AP is AP201C in the application scenario shown in fig. 2. The primary channels of the operating channels of AP201A include channel 36 and channel 40, and the primary channel of the operating channel of AP201C is channel 44.

2. A relationship between the first channel group and an operating channel of the first AP.

The first channel group belongs to the operating channel of the first AP and includes the primary channel of the operating channel of the first AP. If the operating channel of the first AP has a plurality of primary channels, the first channel group includes the primary channels of the operating channel of the first AP, and means that the first channel group includes at least one primary channel of the operating channel of the first AP.

The first channel group may include only the primary channel of the first AP's operating channel. For example, if the first AP is the AP201A in the application scenario shown in fig. 2, and the main channel of the working channels of the AP201A includes the channel 36 and the channel 40, the first channel group may include the channel 36, or include the channel 40, or include the channel 36 and the channel 40.

Alternatively, the first channel group may include a secondary channel of the operating channel of the first AP in addition to the primary channel of the operating channel of the first AP. For example, if the first AP is the AP201A in the application scenario shown in fig. 2, the primary channel of the working channels of the AP201A includes the channel 36 and the channel 40, the secondary channel of the working channels of the AP201A includes the channel 44 and the channel 48, and the first channel group may include the channel 40 and the channel 44, or include the channel 36, the channel 40 and the channel 44, or include the channel 40, the channel 44 and the channel 48, and so on.

3. The relationship between the second channel group and the first channel group and the operating channel of the first AP.

The second channel group includes one or more channels of the working channels of the first AP other than the channels of the first channel group, that is, the second channel group belongs to the working channels of the first AP and does not overlap with the first channel group. For example, the first AP is AP201A in the application scenario shown in fig. 2, the first channel group includes channel 36, and the second channel group includes channel 40, channel 44, and channel 48.

4. A relationship between the first target channel group and the first channel group and an operating channel of the second AP.

The first target channel group belongs to and includes a primary channel of the operating channel of the second AP, and the first target channel group does not include any channel in the first channel group. The first target channel group does not include any channel in the first channel group, that is, the first target channel group is not overlapped with the first channel group, so that co-frequency interference caused by uplink transmission of the STA associated with the first AP and downlink transmission of the second AP can be avoided.

In a first possible implementation, the first target channel group belongs to an operating channel of the first AP. For example, the first AP is AP201A in the application scenario shown in fig. 2, the second AP is AP 201B in the application scenario shown in fig. 2, the first channel group includes channel 40 and channel 44, and the first target channel group includes channel 36 and channel 48. In this implementation, the first target channel group may overlap with the second channel group, i.e., the first AP may transmit the collaborative announcement frame on the channel allocated to the second AP. Alternatively, the first target channel group may not overlap with the second channel group, which is not limited in this embodiment of the application.

In a second possible implementation, the first target channel group does not belong to the operating channel of the first AP. For example, the first AP is AP201C in the application scenario shown in fig. 2, the second AP is AP201A in the application scenario shown in fig. 2, the first channel group includes channel 44, and the first target channel group includes channel 36 and channel 40.AP 201C may send a coordinated announcement frame on channel 48 instructing AP201A to use channel 36 and channel 40.

In a third possible implementation, a portion of the channels of the first target channel group belong to the operating channels of the first AP. For example, the first AP is AP201C in the application scenario shown in fig. 2, the second AP is AP201A in the application scenario shown in fig. 2, the first channel group includes channel 44, and the first target channel group includes channel 36 and channel 48. Wherein, the channel 48 in the first target channel group belongs to the working channel of the AP201C, and the channel 36 in the first target channel group does not belong to the working channel of the AP201C.

Optionally, the cooperative announcement frame further includes an identification of a third AP, an indication of a second target channel group, and an indication of the first transmission duration. The cooperative announcement frame is further configured to instruct the third AP to use the second target channel group within the first transmission duration after receiving the cooperative announcement frame. The working channel of the third AP overlaps with the working channel of the first AP, and the relationship between the working channel of the third AP and the working channel of the first AP may refer to the relationship between the working channel of the second AP and the working channel of the first AP, which is not described herein again in this embodiment of the present application. The second target channel group belongs to and includes a primary channel of the operating channel of the third AP, and the second target channel group does not include the first channel group and any channel of the first target channel group. The relationship between the second target channel group and the first channel group and the working channel of the third AP may refer to the relationship between the first target channel group and the working channel of the first channel group and the working channel of the second AP, and the details of the embodiment of the present application are not repeated herein. The second target channel group does not include any channel in the first target channel group, that is, the second target channel group is not overlapped with the first target channel group, so that co-channel interference caused by downlink transmission of the second AP and the third AP can be avoided.

Optionally, the first AP broadcasts a collaborative announcement frame on a channel common to the second AP and the third AP, and indicates a first target channel group for the second AP and a second target channel group for the third AP in the collaborative announcement frame, respectively. For example, if the first AP is an AP201A in the application scenario shown in fig. 2, the second AP is an AP 201B in the application scenario shown in fig. 2, the third AP is an AP201C in the application scenario shown in fig. 2, the first channel group includes the channel 36, the first target channel group includes the channel 40, and the second target channel group includes the channel 44 and the channel 48, the AP201A may broadcast and transmit the cooperative announcement frame on the channel 44 and/or the channel 48.

In this embodiment, the primary AP may instruct one or more secondary APs to use a corresponding channel group within a specified transmission duration after receiving the cooperative announcement frame by sending a cooperative announcement frame, so as to implement that the one or more secondary APs cooperatively perform downlink transmission in an STA uplink transmission process associated with the primary AP.

Or, when the primary AP determines to select the multiple secondary APs for downlink transmission cooperatively, the primary AP may also use the OFDMA technique to simultaneously send cooperative announcement frames to the multiple secondary APs, where each cooperative announcement frame is used to indicate the corresponding secondary AP to use the corresponding channel group within the specified transmission duration after receiving the cooperative announcement frame.

In the embodiment of the present application, the cooperative announcement frame carries an identifier of a secondary AP, an indication of a channel group, and an indication of a transmission duration, so as to indicate that the secondary AP uses the channel group within the transmission duration when receiving the cooperative announcement frame, and the cooperative announcement frame is used to trigger the secondary AP to perform downlink transmission in cooperation during an uplink transmission process of an STA associated with a primary AP. In addition, in the cooperative transmission mechanism provided by the present application, the primary channel of the working channel of each AP is fixed, and after receiving the cooperative announcement frame from the primary AP, the secondary AP may directly use the channel indicated by the cooperative announcement frame for downlink transmission, so that the cooperative efficiency is high.

Optionally, the collaborative announcement frame provided in the embodiment of the present application is a control frame. For example, fig. 4 is a schematic structural diagram of a collaborative announcement frame according to an embodiment of the present application. As shown in fig. 4, the collaborative announcement Frame includes a Frame control (Frame control) field, a duration (duration) field, a Receiver Address (RA) field, a Transmitter Address (TA) field, a common info field, a user info list (user info list) field (variable length), a padding (padding) field (optional), and a Frame Check Sequence (FCS) field, etc. Wherein, the frame control field, the duration field, the RA field and the TA field belong to the frame header. The cooperative announcement frame may be a newly defined control frame, and for example, a control frame having a subtype value (subtype value) of 0011 in a frame control field may be defined as the cooperative announcement frame. Alternatively, the cooperative announcement frame may also be a type of trigger frame (trigger frame) defined in the WLAN protocol, for example, a trigger frame whose trigger type (trigger type) in the public information field has a value of one of 8 to 15 may be defined as the cooperative announcement frame.

Optionally, the identity of the secondary AP, the indication of the channel group, and the indication of the transmission duration included in the collaborative announcement frame are in a user information list field. For example, referring to fig. 4, the user information list field includes a neighbor AP identification field, a channel bandwidth field, and a transmission duration field. The length of the neighbor AP identification field is 48 bits (bit), and is used for carrying the identification of the neighbor AP. The length of the channel identification field is 16 bits, and the channel identification field is used for bearing the channel number of the channel group. The length of the channel bandwidth field is 8 bits, and is used for bearing the total bandwidth size of the channel group. The length of the transmission duration field is 32 bits, and is used for bearing the indication of the transmission duration.

Optionally, the first transmission duration is greater than a duration threshold. Since the first transmission duration includes the transmission time of the cooperative announcement frame and the time for the second AP to parse the cooperative announcement frame, if the first transmission duration is too short, the second AP may not be able to send a downlink frame within the first transmission duration in which the cooperative announcement frame is received or may not be able to send a downlink frame in time, which means cooperative transmission cannot be achieved. Therefore, by setting the first transmission duration to be greater than the duration threshold, the reliability and the effectiveness of the cooperative transmission can be improved.

After receiving the RTS frame from the STA, the first AP may determine a first channel group for the STA to use, and then determine a first transmission duration according to a relationship between the first channel group and a channel group used by the STA to send the RTS frame and the second transmission duration. If the first transmission duration is greater than the duration threshold, the first AP performs step 302. If the first transmission duration is less than or equal to the duration threshold, the first AP sends a CTS frame to the STA on the channel group that the STA uses to send RTS frames, i.e., the first AP permits the STA to use the channel group that the STA uses to send RTS frames.

Optionally, the first AP has a plurality of neighbor APs. The first AP may select one or more APs from the plurality of neighbor APs as secondary APs for cooperative transmission. For example, the first AP stores service information of a plurality of neighbor APs, and determines cooperative transmission priorities of the plurality of neighbor APs according to the service information of the plurality of neighbor APs, and performs cooperative transmission using one or more neighbor APs with the highest cooperative transmission priority as a secondary AP. The data volume to be transmitted, the time length to be transmitted, the service priority of the data to be transmitted, and the user priority of the data to be transmitted of the neighbor AP are all positively correlated with the cooperative transmission priority, that is, if the data volume to be transmitted of the neighbor AP is larger, the time length to be transmitted is longer, the service priority of the data to be transmitted is higher, and the user priority of the data to be transmitted is higher, the cooperative transmission priority of the neighbor AP is higher.

The first AP sends a CTS frame to the associated STA on the first channel group, which indicates that the first AP permits the STA to occupy the channel in the first channel group, that is, the first AP allocates the channel in the first channel group to the STA for use, and then the STA only sends an uplink frame on the first channel group on which the CTS frame is received, so the first AP may further perform the following step 303.

Step 303, the first AP receives a frame from the STA associated with the first AP on the first channel group.

After receiving the cooperative announcement frame from the first AP on the primary channel and/or the secondary channel of the working channel of the second AP, the second AP may parse the cooperative announcement frame to obtain a first target channel group and a first transmission duration that are allocated by the first AP to the second AP, and then the second AP may send a frame to an STA associated with the second AP on the first target channel group within the first transmission duration in which the cooperative announcement frame is received. Optionally, if the duration of the frame transmitted by the second AP to the STA associated with the second AP is less than the first transmission duration, a padding field may be added to the frame to maintain alignment with the first AP.

In the embodiment of the present application, an implementation flow of the data transmission method shown in fig. 3 is described by taking an example where a first AP and a second AP use a same operating channel with a bandwidth of 40 MHz. Wherein the working channels of the first AP and the second AP respectively comprise a primary channel of 20MHz and a secondary channel of 20 MHz. The primary channel of the working channel of the first AP overlaps the secondary channel of the working channel of the second AP, and the secondary channel of the working channel of the first AP overlaps the primary channel of the working channel of the second AP. A first STA is associated with the first AP and a second STA is associated with the second AP.

For example, fig. 5 is a schematic diagram of a frame transmission sequence according to an embodiment of the present application. As shown in fig. 5, after the first STA contends for the channel, an RTS frame is sent to the first AP over the 40MHz operating channel of the first AP, the RTS frame including a transmission duration T1. After receiving the SIFS of the RTS frame, the first AP sends a CTS frame to the first STA on the 20MHz primary channel of the first AP, and simultaneously sends a cooperative announcement frame to the second AP on the 20MHz secondary channel of the first AP, where the CTS frame includes a transmission duration T2, and the cooperative announcement frame includes an indication of the primary channel of the working channel of the second AP and the transmission duration T2. And the first STA sends an uplink frame to the first AP on the 20MHz main channel of the first AP within the transmission time length T2 after receiving the CTS frame. And the second AP sends a downlink frame to the second STA on a20 MHz main channel of the second AP within the transmission time length T2 after receiving the cooperative announcement frame.

For another example, fig. 6 is a schematic diagram of another frame transmission sequence provided in this embodiment. As shown in fig. 6, after the first STA contends for the channel, an RTS frame is sent to the first AP on the 20MHz primary channel of the first AP, the RTS frame including a transmission duration T3. After receiving the SIFS of the RTS frame, the first AP sends a CTS frame to the first STA on the 20MHz primary channel of the first AP, and simultaneously sends a cooperative announcement frame to the second AP on the 20MHz secondary channel of the first AP, where the CTS frame includes a transmission duration T4, and the cooperative announcement frame includes an indication of the primary channel of the working channel of the second AP and the transmission duration T4. And the first STA sends an uplink frame to the first AP on the 20MHz main channel of the first AP within the transmission time length T4 after receiving the CTS frame. And the second AP sends the downlink frame to the second STA on the 20MHz primary channel of the second AP within the transmission duration T4 after receiving the cooperative announcement frame.

In summary, in the data transmission method provided in this embodiment of the present application, after an STA contending for a channel sends an RTS frame to an AP associated with the STA, the AP associated with the STA may allocate a channel other than a channel used by the STA to other APs deployed in the same frequency as the AP, so that the other APs allocated to the channel can send a downlink frame to the STA associated with the STA on the allocated channel in a process that the STA sends an uplink frame to the AP associated with the STA, thereby implementing uplink and downlink cooperative transmission between the STA and a non-associated AP, improving flexibility of data transmission, and improving utilization rate of bandwidth resources.

A second embodiment of the present application: fig. 7 is a flowchart illustrating another data transmission method according to an embodiment of the present application. The method may be applied in an application scenario as shown in fig. 2. As shown in fig. 7, the method includes:

step 701, the AP receives a preamble of a first frame from a STA not associated with the AP, the preamble of the first frame including an indication of a transmission duration of a data portion of the first frame.

Optionally, the indication of the transmission duration of the data portion of the first frame may be the transmission duration of the data portion of the first frame, or may also be the data amount of the data portion of the first frame, and the AP may calculate the transmission duration of the data portion of the first frame according to the data amount of the data portion of the first frame and the transmission rate. Alternatively, the indication of the transmission duration of the data portion of the first frame may also be the transmission duration of the first frame, and the AP may calculate the transmission duration of the data portion of the first frame according to the reception duration of the preamble of the first frame and the transmission duration of the first frame.

Optionally, the first frame is a data frame, a control frame or a management frame. In the embodiment of the present application, the preamble of the first frame refers to a preamble of a physical layer (PHY) header, and the data portion of the first frame refers to a portion of the first frame after the preamble. For example, the data portion of the first frame includes a MAC header and a payload (payload) portion.

Optionally, after the AP receives the preamble of the frame from the STA on the working channel, the AP obtains a basic service set color (BSS color) value by analyzing the preamble of the frame, and then determines whether the frame is from the STA associated with the AP or from the STA not associated with the AP according to the BSS color value. Alternatively, after receiving a frame from an STA on the working channel, the AP obtains the BSSID (i.e., the sender address) of the TA field by parsing the MAC header of the data portion of the frame, and then determines whether the frame is from an STA associated with the AP or from an STA not associated with the AP according to the BSSID.

Step 702, when the primary channel of the working channel of the AP is idle, the AP transmits a second frame to the STA associated with the AP on the primary channel of the working channel of the AP within the transmission duration after receiving the preamble of the first frame.

Optionally, the second frame is a data frame, a control frame or a management frame. After determining that the received frame is from the STA which is not associated with the AP, the AP may first detect whether a main channel of a working channel of the AP is idle, and if the main channel of the working channel of the AP is idle, the AP decides whether to perform cooperative transmission; if the main channel of the working channel of the AP is busy, the AP keeps silent.

Optionally, when the main channel of the working channel of the AP is idle and the transmission duration of the data portion of the first frame is greater than the duration threshold, the AP transmits the second frame to the STA associated with the AP on the main channel of the working channel of the AP.

Because the AP may send the downlink frame after the interval SIFS after analyzing the preamble within the sending time length after receiving the preamble of the first frame, if the sending time length of the data portion of the first frame is too small, the AP may not be in time to send the downlink frame within the sending time length or may not be in time to send one downlink frame, that is, cooperative transmission cannot be achieved. Therefore, by setting the condition that the sending duration of the data part of the first frame is greater than the duration threshold as the condition that the AP sends the second frame to the STA associated with the AP, the reliability and the effectiveness of cooperative transmission can be improved.

Optionally, when there is an idle secondary channel in the working channel of the AP, the AP may further send a second frame to the STA associated with the AP on the idle secondary channel within the sending duration after receiving the preamble of the first frame. The AP transmits the second frame to the STA associated with the AP on the primary channel and the idle secondary channel, which may be understood as that the AP transmits the second frame to the STA associated with the AP by using the total bandwidth of the primary channel and the idle secondary channel, and does not mean that the AP transmits the second frame to the STA associated with the AP on the primary channel and the idle secondary channel, respectively, that is, does not repeatedly transmit the second frame.

In the embodiment of the application, the AP sends the second frame to the STA associated with the AP by using the total bandwidth of the primary channel and the idle secondary channel, so that on one hand, the bandwidth resource can be fully utilized, and the utilization rate of the bandwidth resource is improved. On the other hand, the transmission time of the second frame can be reduced, so that the AP can transmit more data to the STA associated with the AP within a specified time duration, thereby improving the transmission efficiency.

In the embodiment of the present application, an implementation flow of the data transmission method shown in fig. 7 is described by taking an application scenario that includes a third AP, a third STA associated with the third AP, a fourth AP, and a fourth STA associated with the fourth AP as an example. Wherein the third AP and the fourth AP use the same operating channel with a bandwidth of 40MHz, and the operating channels of the third AP and the fourth AP respectively include a primary channel with 20MHz and a secondary channel with 20 MHz. The primary channel of the working channel of the third AP overlaps the secondary channel of the working channel of the fourth AP, and the secondary channel of the working channel of the third AP overlaps the primary channel of the working channel of the fourth AP.

For example, fig. 8 is a schematic diagram of another frame transmission sequence provided in the embodiment of the present application. As shown in fig. 8, after the third STA contends for the channel, an uplink frame is transmitted to the third AP on the 20MHz main channel of the third AP, where the uplink frame includes a preamble and a data portion, and the preamble includes an indication of a transmission duration T5 of the data portion of the uplink frame. And the fourth AP sends the downlink frame to the fourth STA on the 20MHz main channel of the fourth AP within the sending time length T5 after receiving the lead code of the uplink frame and after the SIFS interval.

In summary, in the data transmission method provided in the embodiment of the present application, when an STA contending for a channel sends an uplink frame to an AP associated with the STA, other APs deployed in the same frequency as the AP associated with the STA may monitor the uplink frame on a working channel, and send a downlink frame to the STA associated with the STA on a main channel when the main channel is idle, that is, other APs deployed in the same frequency as the AP associated with the STA contending for the channel may actively initiate cooperative transmission to perform downlink transmission by using a channel bandwidth unused by the STA, thereby implementing uplink and downlink cooperative transmission between the STA and a non-associated AP, improving flexibility of data transmission, and also improving utilization rate of bandwidth resources.

The sequence of the steps of the data transmission method provided by the embodiment of the application can be properly adjusted, and the steps can be correspondingly increased or decreased according to the situation. Any method that can be easily conceived by a person skilled in the art within the technical scope of the present disclosure shall be covered by the protection scope of the present disclosure. The data transmission method shown in fig. 3 and the data transmission method shown in fig. 7 may be applied in the same application scenario, for example, a primary AP may allocate channels to some secondary APs, and a secondary AP not allocated a channel may actively perform cooperative transmission when its own primary channel is idle, which is not described herein again.

Fig. 9 is a schematic structural diagram of an AP according to an embodiment of the present application. The AP is a first AP of the at least two APs.

As shown in fig. 9, the first AP 90 includes:

a receiving module 901 is configured to receive an RTS frame from an STA associated with a first AP.

A sending module 902, configured to send, to the STA, a CTS frame in response to the RTS frame on the first channel group, and send, to the second channel group, a cooperative announcement frame at the same time, where the CTS frame includes an indication of the first transmission duration, and the cooperative announcement frame includes an identifier of the second AP, an indication of the first target channel group, and an indication of the first transmission duration, and the cooperative announcement frame is used to indicate that the second AP uses the first target channel group within the first transmission duration after receiving the cooperative announcement frame.

The working channel of the second AP overlaps with the working channel of the first AP, the first channel group belongs to the working channel of the first AP and includes a main channel of the working channel of the first AP, the second channel group includes one or more channels of the working channels of the first AP other than the channels in the first channel group, the first target channel group belongs to the working channel of the second AP and includes the main channel of the working channel of the second AP, and the first target channel group does not include any channel in the first channel group.

Optionally, the first AP receives the RTS frame from the STA on a third channel group that includes the first channel group and that includes channels of the operating channels of the first AP that are not in the first channel group.

Optionally, the RTS frame comprises an indication of a second transmission duration, the first transmission duration being greater than or equal to the second transmission duration.

Optionally, the cooperative announcement frame further includes an identifier of a third AP, an indication of the second target channel group, and an indication of the first transmission duration, and the cooperative announcement frame is further configured to indicate the third AP to use the second target channel group within the first transmission duration after the cooperative announcement frame is received; the working channel of the third AP overlaps with the working channel of the first AP, the second target channel group belongs to the working channel of the third AP and includes a main channel of the working channel of the third AP, and the second target channel group does not include any channel of the first channel group and the first target channel group.

Optionally, the receiving module 901 is further configured to receive a frame from an STA on the first channel group.

Fig. 10 is a schematic structural diagram of an AP according to an embodiment of the present application. As shown in fig. 10, the AP 100 includes:

a receiving module 1001 configured to receive a preamble of a first frame from a STA that is not associated with an AP, the preamble of the first frame including an indication of a transmission duration of a data portion of the first frame.

A sending module 1002, configured to send, when a primary channel of an operating channel of an AP is idle, a second frame to an STA associated with the AP on the primary channel of the operating channel of the AP within a sending duration after receiving a preamble of a first frame.

Optionally, the transmitting module 1002 is further configured to, when there is an idle secondary channel in the working channel of the AP, transmit a second frame to the STA associated with the AP on the idle secondary channel within a transmission duration after receiving the preamble of the first frame.

Optionally, the sending module 1002 is configured to: and when the main channel of the working channel of the AP is idle and the sending duration is greater than the duration threshold, sending a second frame to the STA associated with the AP on the main channel of the working channel of the AP.

With regard to the apparatus in the above-described embodiment, the specific manner in which each module performs the operation has been described in detail in the embodiment related to the method, and will not be elaborated here.

An embodiment of the present application provides an AP, including: a transceiver and an antenna. The transceiver is configured to perform transceiving actions on an operating channel of the AP using the antenna, so as to implement the data transmission method shown in fig. 3 or fig. 7.

Optionally, the transceiver comprises a baseband processing circuit and a radio frequency processing circuit. The baseband processing circuit may perform the processing actions related to the data transmission method, and the baseband processing circuit may further perform the transceiving actions related to the data transmission method through the radio frequency processing circuit.

Optionally, the AP further comprises a processor. The processor is used for executing the processing action related to the data transmission method, and the transceiver executes the transceiving action related to the data transmission method under the control of the processor.

For example, fig. 11 is a block diagram of an AP provided in an embodiment of the present application. As shown in fig. 11, the AP 110 includes: a processor 1101, a transceiver 1102, and an antenna 1103. The transceiver 1102 is configured to perform transceiving actions of the AP in the above-described method embodiment using the antenna 1103 under the control of the processor 1101.

The processor 1101 may be a Central Processing Unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of programs according to the present disclosure. In particular implementations, an AP may include multiple processors, as one embodiment. Each of these processors may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may refer to one or more devices, circuits, and/or processing cores that process data (e.g., computer program instructions).

Optionally, the AP 110 further comprises a memory, a communication bus and a communication interface (not shown in the figure).

The communication bus may include a path that transfers information between the aforementioned components.

The Memory may be, but is not limited to, a read-only Memory (ROM) or other type of static storage device that may store static information and instructions, a Random Access Memory (RAM) or other type of dynamic storage device that may store information and instructions, an electrically erasable programmable read-only Memory (EEPROM), a compact disk read-only Memory (CD-ROM) or other optical disk storage, optical disk storage (including compact disk, laser disk, optical disk, digital versatile disk, blu-ray disk, etc.), a magnetic disk or other magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. The memory may be self-contained and coupled to the processor via a communication bus. The memory may also be integral to the processor.

The memory is used for storing program codes for executing the scheme of the application and is controlled by the processor to execute. The processor is configured to execute program code stored in the memory. One or more software modules may be included in the program code. The one or more software modules may be software modules provided in either of the embodiments of fig. 9 or fig. 10.

A communication interface for communicating with other devices or a communication network, such as a WLAN or the like.

An embodiment of the present application further provides a data transmission system, including: the system comprises a STA, a first AP and a second AP, wherein working channels of the first AP and the second AP are overlapped. The STA associates with a first AP for performing the method shown in fig. 3, or a second AP for performing the method shown in fig. 7.

Embodiments of the present application also provide a computer-readable storage medium, which stores instructions that, when executed by a processor of a computer device, implement the data transmission method shown in fig. 3 or fig. 7.

It will be understood by those skilled in the art that all or part of the steps for implementing the above embodiments may be implemented by hardware, or may be implemented by a program instructing relevant hardware, where the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.

In the embodiments of the present application, the terms "first", "second", and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The term "and/or" in this application is only one kind of association relationship describing the association object, and means that there may be three kinds of relationships, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

The above description is only exemplary of the present application and is not intended to limit the present application, and any modifications, equivalents, improvements, etc. made within the spirit and principles of the present application are intended to be included within the scope of the present application.

Claims

1. A method of data transmission, the method comprising:

a first Access Point (AP) receives a Request To Send (RTS) frame from a Station (STA) associated with the first AP;

the first AP sending, to the STA, an explicit CTS frame to respond to the RTS frame on a first channel group, and sending, at the same time, a cooperative announcement frame on a second channel group, where the CTS frame includes an indication of a first transmission duration, the cooperative announcement frame includes an identifier of a second AP, an indication of a first target channel group, and an indication of the first transmission duration, and the cooperative announcement frame is used to indicate the second AP to use the first target channel group within the first transmission duration after receiving the cooperative announcement frame;

wherein the working channel of the second AP overlaps with the working channel of the first AP, the first channel group belongs to the working channel of the first AP and includes a main channel of the working channel of the first AP, the second channel group includes one or more channels of the working channel of the first AP except for a channel in the first channel group, the first target channel group belongs to the working channel of the second AP and includes a main channel of the working channel of the second AP, and the first target channel group does not include any channel in the first channel group.

2. The method of claim 1, wherein the primary channel of the operating channel of the second AP does not overlap with the primary channel of the operating channel of the first AP.

3. The method of claim 1 or 2, wherein the first AP receives the RTS frame from the STA on a third channel group that includes the first channel group and that includes channels of the operating channels of the first AP that are not in the first channel group.

4. The method of claim 3, wherein the RTS frame comprises an indication of a second transmission duration, and wherein the first transmission duration is greater than or equal to the second transmission duration.

5. The method according to any of claims 1 to 4, wherein the first transmission duration is greater than a duration threshold.

6. The method of any of claims 1 to 5, wherein a start time and an end time for the first AP to transmit the CTS frame are the same as a start time and an end time for transmitting the collaborative announcement frame, respectively, and wherein the CTS frame comprises a padding field.

7. The method of any of claims 1 to 6, wherein the cooperative announcement frame further comprises an identification of a third AP, an indication of a second target channel group, and an indication of the first transmission duration, and wherein the cooperative announcement frame is further configured to instruct the third AP to use the second target channel group for the first transmission duration after receiving the cooperative announcement frame;

wherein the working channel of the third AP overlaps with the working channel of the first AP, the second target channel group belongs to the working channel of the third AP and includes a main channel of the working channel of the third AP, and the second target channel group does not include any channel of the first channel group and the first target channel group.

8. The method of any of claims 1 to 7, further comprising:

the first AP receives frames from the STA on the first channel group.

9. A method of data transmission, the method comprising:

an Access Point (AP) receiving a preamble of a first frame from a Station (STA) not associated with the AP, the preamble of the first frame comprising an indication of a transmission duration of a data portion of the first frame;

and when the main channel of the working channel of the AP is idle, the AP sends a second frame to the STA associated with the AP on the main channel of the working channel of the AP within the sending duration after receiving the lead code of the first frame.

10. The method of claim 9, further comprising:

and when an idle secondary channel exists in the working channel of the AP, the AP sends the second frame to the STA associated with the AP on the idle secondary channel within the sending time length after receiving the lead code of the first frame.

11. The method of claim 9 or 10, wherein the AP transmitting a second frame to the STA associated with the AP on the primary channel of the AP's operating channel comprises:

and when the sending duration is greater than a duration threshold, the AP sends the second frame to the STA associated with the AP on a main channel of a working channel of the AP.

12. An access point, AP, wherein the AP is a first AP of at least two APs, wherein the first AP comprises:

a receiving module, configured to receive a request to send RTS frame from a station STA associated with the first AP;

a sending module, configured to send, to the STA, an explicit CTS frame for sending in response to the RTS frame on a first channel group, and send, to a second channel group, a cooperative announcement frame at the same time, where the CTS frame includes an indication of a first transmission duration, the cooperative announcement frame includes an identifier of a second AP, an indication of a first target channel group, and an indication of the first transmission duration, and the cooperative announcement frame is used to indicate that the second AP uses the first target channel group within the first transmission duration after receiving the cooperative announcement frame;

wherein the working channel of the second AP overlaps with the working channel of the first AP, the first channel group belongs to the working channel of the first AP and includes a main channel of the working channel of the first AP, the second channel group includes one or more channels of the working channels of the first AP other than the channels in the first channel group, the first target channel group belongs to the working channel of the second AP and includes a main channel of the working channel of the second AP, and the first target channel group does not include any channel in the first channel group.

13. The first AP of claim 12, wherein the primary channel of the operating channel of the second AP is non-overlapping with the primary channel of the operating channel of the first AP.

14. The first AP of claim 12 or 13, wherein the first AP receives the RTS frame from the STA on a third channel group that includes the first channel group and that includes channels of the operating channel of the first AP that are not in the first channel group.

15. The first AP of claim 14, wherein the RTS frame comprises an indication of a second transmission duration, and wherein the first transmission duration is greater than or equal to the second transmission duration.

16. The first AP of any one of claims 12-15, wherein the first transmission duration is greater than a duration threshold.

17. The first AP of any one of claims 12-16, wherein a start time and an end time for the first AP to transmit the CTS frame are the same as a start time and an end time, respectively, for transmitting the cooperative announcement frame, and wherein the CTS frame includes a padding field.

18. The first AP of any one of claims 12 to 17, wherein the cooperative announcement frame further includes an identifier of a third AP, an indication of a second target channel group, and an indication of the first transmission duration, and wherein the cooperative announcement frame is further configured to instruct the third AP to use the second target channel group for the first transmission duration after receiving the cooperative announcement frame;

19. The first AP according to any one of claims 1 to 18,

the receiving module is further configured to receive a frame from the STA on the first channel group.

20. An access point, AP, comprising:

a receiving module to receive a preamble of a first frame from a station STA that is not associated with the AP, the preamble of the first frame including an indication of a transmission duration of a data portion of the first frame;

a sending module, configured to send, when a primary channel of a working channel of the AP is idle, a second frame to an STA associated with the AP on the primary channel of the working channel of the AP within the sending duration after receiving the preamble of the first frame.

21. The AP of claim 20,

the sending module is further configured to send the second frame to an STA associated with the AP on the idle secondary channel within the sending duration after receiving the preamble of the first frame when the idle secondary channel exists in the working channel of the AP.

22. The AP of claim 20 or 21, wherein the sending module is configured to:

and when the main channel of the working channel of the AP is idle and the sending duration is greater than the duration threshold, sending the second frame to the STA associated with the AP on the main channel of the working channel of the AP.

23. A data transmission system, comprising: a station STA, a first access point AP and a second AP, wherein the operating channels of the first AP and the second AP overlap, the STA being associated with the first AP, the first AP being configured to perform the method according to any one of claims 1 to 8, or the second AP being configured to perform the method according to any one of claims 9 to 11.

24. An access point, AP, comprising: a transceiver and an antenna;

the transceiver is configured to perform transceiving actions on an operating channel of the AP using the antenna, and implement the data transmission method according to any one of claims 1 to 11.

25. A computer-readable storage medium having stored thereon instructions which, when executed by a processor of a computer device, carry out a data transmission method according to any one of claims 1 to 11.