WO2019001568A1

WO2019001568A1 - Method and device for establishing wlan link

Info

Publication number: WO2019001568A1
Application number: PCT/CN2018/093657
Authority: WO
Inventors: 顾燕杰; 王树起; 李卫华
Original assignee: 华为技术有限公司
Priority date: 2017-06-30
Filing date: 2018-06-29
Publication date: 2019-01-03
Also published as: CN109429359B; CN109429359A

Abstract

A method and a device for establishing a WLAN link. The method comprises: a first network device using an initial bandwidth to broadcast a probe request; detecting whether a probe response corresponding to the probe request and sent by a second network device has been received and, if the probe response has not been received, using an adjusted bandwidth to broadcast the probe request; and then beginning to re-execute from the aforementioned step of detecting whether a probe response corresponding to the probe request and sent by second network device has been received, the adjusted bandwidth being a smaller bandwidth than the previously used bandwidth; and, if a probe response is received, then establishing a WLAN link with the second network device, the bandwidth of the WLAN link being the bandwidth used when receiving the probe response. The solution provided in the embodiments of the present application uses a smaller adjusted bandwidth to re-send a probe request when a probe response corresponding to the probe request has not been received, and thereby expands the scope of the probe, ensuring successful establishment of a WLAN link.

Description

WLAN link establishment method and device

This application claims priority to the Chinese Patent Application of the State Intellectual Property Office of China, Application No. 201710527445.9, and the invention titled "WLAN Link Establishment Method and Equipment" on June 30, 2017, the entire contents of which are incorporated herein by reference. In the application.

Technical field

The embodiments of the present invention relate to the field of communications technologies, and in particular, to a wireless local area network (WLAN) link establishing method and device.

Background technique

WLAN is a very convenient data transmission system, which refers to the application of wireless communication technology to interconnect network devices to form a network system that can communicate with each other and achieve resource sharing.

Before establishing a WLAN link, the network device must first find other network devices that can establish a WLAN link with it. In the prior art, a network device transmits a probe request using a 20 MHz bandwidth to find other network devices with which a WLAN link can be established.

Under normal circumstances, the maximum transmission distance that can be reached by a probe request sent in a 20MHz bandwidth is about 400 meters. If the distance between a network device and another network device exceeds 400 meters, another network device cannot receive it. The probe request caused the two to fail to establish a WLAN link.

Therefore, the prior art has a problem that a WLAN link cannot be established due to a limited detection range.

Summary of the invention

The embodiment of the present application provides a method and a device for establishing a WLAN link, which are used to solve the problem that the WLAN link cannot be established due to the limited detection range in the prior art.

In a first aspect, the embodiment of the present application provides a method for establishing a WLAN link, where the method includes: the first network device uses an initial bandwidth to broadcast a probe request; and the first network device detects whether the second network device receives the probe request that is sent by the second network device. If the probe response is not received, the first network device uses the adjusted bandwidth broadcast probe request, and starts to perform the step of detecting whether the probe response corresponding to the probe request sent by the second network device is received. Adjusting the bandwidth refers to a bandwidth smaller than the bandwidth used last time; if the probe response is received, the first network device establishes a WLAN link with the second network device, wherein the bandwidth of the WLAN link is when the probe response is received. The bandwidth used.

In the solution provided by the embodiment of the present application, the probe request is re-transmitted with a smaller adjustment bandwidth without receiving the probe response corresponding to the probe request, thereby expanding the detection range and ensuring successful establishment of the WLAN link.

In one possible design, the initial bandwidth is 20 MHz; in the case where the probe response corresponding to the probe request transmitted using the initial bandwidth is not received, the adjustment bandwidth is 1 MHz.

In the solution provided by the embodiment of the present application, the first network device directly uses the lowest bandwidth of 1 MHz as the adjustment bandwidth to obtain the maximum coverage of the probe request, and avoids adjusting the bandwidth of sending the probe request multiple times, thereby saving processing overhead.

In another possible design, the method further includes: the first network device sends the first bandwidth capability information to the second network device, and receives the second bandwidth capability information sent by the second network device, where the first bandwidth capability information For indicating the type of bandwidth supported by the first network device, the second bandwidth capability information is used to indicate the type of bandwidth supported by the second network device.

In the solution provided by the embodiment of the present application, the first network device and the second network device record the bandwidth capability of the other party, so as to use the bandwidth that both parties can use for data transmission in the adjustment process described later, and ensure the accuracy of the bandwidth adjustment. And help to increase the efficiency of bandwidth adjustment.

In another possible design, after the first network device establishes a WLAN link with the second network device, the method further includes: in the process of transmitting data by using the WLAN link, the first network device acquires the sending and receiving state information, and the sending and receiving state information is used. The first network device adjusts the bandwidth of the WLAN link to the first bandwidth, and sends the first bandwidth to the second network device by using the first bandwidth, if the sending and receiving state information meets the preset condition. An information frame; if the first network device receives the first acknowledgment signal corresponding to the first information frame sent by the second network device, the first network device determines to use the first bandwidth to transmit data.

In another possible design, after the first network device establishes the WLAN link with the second network device, the method further includes: if the first network device receives the second information frame sent by the second network device by using the second bandwidth, The second network device sends a second acknowledgement signal corresponding to the second information frame, where the second bandwidth is obtained by adjusting the bandwidth of the WLAN link by the second network device.

The embodiments of the present application provide two types of bandwidth adjustment modes, namely active adjustment and passive adjustment. By dynamically adjusting the bandwidth of the WLAN link after establishing the WLAN link, balancing the throughput requirements with the signal coverage requirements, maximizing the throughput rate while ensuring that the WLAN links are not disconnected. Demand.

On the other hand, the embodiment of the present application provides a network device, which has the function of implementing the foregoing method examples. The functions can be implemented in hardware or in hardware by executing the corresponding software. The hardware or software includes one or more units corresponding to the functions described above.

In one possible design, the structure of the network device includes a processor and a communication interface, and the processor is configured to support the network device to perform the corresponding function in the above method. The communication interface is used to support communication between network devices and other network devices. Further, the network device may further include a memory for coupling with the processor, which stores program instructions and data necessary for the network device.

In another aspect, an embodiment of the present application provides a computer storage medium for storing computer software instructions used by the first network device, including a program designed to perform the above aspects.

In still another aspect, embodiments of the present application provide a computer program product for performing the method of the above aspect when the computer program product is executed.

Compared with the prior art, in the solution provided by the embodiment of the present application, the probe request is re-transmitted with a smaller adjustment bandwidth without receiving the probe response corresponding to the probe request, thereby expanding the detection range and ensuring The WLAN link was successfully established.

DRAWINGS

1 is a schematic diagram of an implementation environment provided by an embodiment of the present application;

2A is a flowchart of a method for establishing a WLAN link according to an embodiment of the present application;

2B is an interaction diagram of a WLAN link setup process exemplarily shown:

3A is a flowchart of a method for establishing a WLAN link according to another embodiment of the present application;

FIG. 3B is an interaction diagram of a bandwidth adjustment process exemplarily shown; FIG.

4A is a flowchart of a method for establishing a WLAN link according to another embodiment of the present application;

4B is an interaction diagram of a bandwidth adjustment process exemplarily shown;

FIG. 5 is a schematic diagram of an application scenario exemplarily shown;

6 is a schematic diagram of another application scenario exemplarily shown;

FIG. 7A is a schematic block diagram of a network device according to an embodiment of the present application; FIG.

FIG. 7B is a schematic structural diagram of a network device according to an embodiment of the present application.

Detailed ways

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

Please refer to FIG. 1 , which shows a schematic diagram of an implementation environment provided by an embodiment of the present application. The implementation environment includes a first network device 110 and a second network device 120.

The network devices (including the first network device 110 and the second network device 120) are devices that have the function of establishing a WLAN link with other network devices. Illustratively, the network device may be a terminal device, such as a mobile phone, a tablet computer, an e-book reader, a multimedia playing device, etc.; or may be a wearable device, such as a smart watch, a smart bracelet, smart glasses, etc.; Toys, such as drones, smart battle cars, etc.; or other devices that have the ability to establish WLAN links, such as Wireless Access Point.

For example, the first network device 110 is a mobile phone, and the second network device 120 is also a mobile phone. For another example, the first network device 110 is a drone, and the second network device 120 is a remote controller or a mobile phone. For another example, the first network device 110 is a mobile phone, and the second network device 120 is an AP.

For convenience of description, in the embodiment of the present application, the foregoing devices having the WLAN link function with other network devices are collectively referred to as network devices.

Please refer to FIG. 2A, which is a flowchart of a method for establishing a WLAN link provided by an embodiment of the present application. This method can be applied to the implementation environment shown in FIG. The method can include the following steps.

Step 201: The first network device broadcasts a probe request by using an initial bandwidth.

The first network device broadcasts a probe request with an initial bandwidth for discovering other network devices capable of establishing a WLAN link with the first network device. The initial bandwidth is the first type of bandwidth used by the first network device to broadcast the probe request. Optionally, the initial bandwidth is 20 MHz.

Step 202: The first network device detects whether a probe response corresponding to the probe request sent by the second network device is received. If not, performing the following step 203; if yes, performing the following step 204.

Signals with different bandwidths have different coverage, and bandwidth is negatively correlated with coverage. The larger the bandwidth, the smaller the coverage; conversely, the smaller the bandwidth, the larger the coverage. Therefore, if the distance between the other network device and the first network device exceeds the coverage of the probe request sent by the first network device, the other network device cannot receive the probe request sent by the first network device, and the corresponding network cannot be sent. Probe response.

If the other network device receives the foregoing probe request, the probe response corresponding to the probe request is sent to the first network device. The other network device that sends the foregoing probe response is the second network device. The number of the second network devices may be one or multiple. Optionally, the second network device sends a probe response by using a bandwidth used by the first network device to send the probe request. For example, the first network device adopts a 20 MHz broadcast probe request, and if another network device receives the probe request, the network device sends a probe response to the first network device by using 20 MHz.

Step 203: The first network device broadcasts the probe request by adjusting the bandwidth, and starts execution again from step 202 above.

After the first network device does not receive the probe response from the other network device within the preset time, the probe request is sent by adjusting the bandwidth, where the adjusted bandwidth refers to a bandwidth smaller than the bandwidth used last time to obtain a larger Coverage. The bandwidths commonly used in WLANs include 1MHz, 5MHz, 10MHz, 20MHz, 40MHz, 80MHz, and 160MHz. Optionally, the adjustment bandwidth is one level lower than the bandwidth used last time. Exemplarily, if the first network device uses the initial bandwidth 20 MHz broadcast probe request, if the probe response is not received, the probe request is broadcast again with the adjusted bandwidth of 10 MHz, and so on, until the probe response is received or the minimum bandwidth is adopted ( Such as 1MHz) as the adjustment bandwidth.

Optionally, the initial bandwidth used by the first network device is 20 MHz, and if the probe response corresponding to the probe request sent by using the initial bandwidth is not received, the adjustment bandwidth is 1 MHz. The first network device directly uses the minimum bandwidth of 1 MHz as the adjustment bandwidth to obtain the maximum coverage of the probe request, avoids adjusting the bandwidth used for sending the probe request multiple times, saves processing overhead, and helps improve the efficiency of establishing the WLAN link.

Step 204: The first network device establishes a WLAN link with the second network device.

After the first network device receives the probe response corresponding to the probe request sent by the second network device, the first network device establishes a WLAN link with the second network device, where the bandwidth of the WLAN link is used when receiving the probe response. Bandwidth.

Optionally, after receiving the probe response sent by the second network device, the first network device sends an association request to the second network device, where the association request is used to request to establish a WLAN link. The bandwidth of the above association request is the same as the bandwidth used by the above probe response. After receiving the association request, the second network device sends the association response with the same bandwidth as the association request. After receiving the association response, the first network establishes a WLAN link with the second network device.

Optionally, the first network device sends the first bandwidth capability information to the second network device, where the first bandwidth capability information is used to indicate the bandwidth type supported by the first network device, and the second network device records the bandwidth type supported by the first network device. . The first network device receives the second bandwidth capability information sent by the second network device, the second network capability information is used to indicate the type of bandwidth supported by the second network device, and the first network device records the supported bandwidth type of the second network device. Illustratively, the first bandwidth capability information indicates that the first network device can use bandwidths of 1 MHz, 5 MHz, 10 MHz, and 20 MHz, and the second bandwidth capability information indicates that the second network device can use bandwidths of 1 MHz, 5 MHz, 10 MHz, 20 MHz, and 40 MHz. The first network device and the second network device record the bandwidth capability of the other party, so as to use the bandwidth that both parties can support for data transmission in the subsequent bandwidth adjustment process. Optionally, the first network device carries the first bandwidth capability information in the association request and sends the information to the second network device, where the second network device can carry the second bandwidth capability information in the association response and send the information to the first network device.

Optionally, when the first network device receives the probe response sent by the multiple second network devices, the first network device selects one network device from the multiple second network devices as the target second network device according to the user requirement, Establishing a WLAN link with the target second network device. Exemplarily, the first network device displays the names of the plurality of second network devices to the user, and the user selects a second network device, and the selected second network device is the target second network device.

Please refer to FIG. 2B, which exemplarily shows an interaction diagram of a WLAN link establishment process. The first network device uses the 20 MHz bandwidth as the initial bandwidth broadcast probe request. The second network device does not receive the probe request sent by the first network device using the 20 MHz bandwidth. The first network device uses the 1 MHz bandwidth as the adjusted bandwidth broadcast probe request without receiving the probe response corresponding to the probe request. The second network device receives the probe request sent by the first network device by using the 1 MHz bandwidth, and sends the probe response by using the same bandwidth. After receiving the foregoing probe response, the first network device sends an association request to the second network device by using a 1 MHz bandwidth. After receiving the association request, the second network device sends an association response to the first network device by using the same bandwidth. After receiving the association response, the first network device establishes a WLAN link with the second network device, where the bandwidth of the WLAN link is 1 MHz.

After the first network device establishes a WLAN link with the second network device for data transmission, the bandwidth needs to be adjusted to meet the throughput requirement or the WLAN link is disconnected. The first network device can adopt active adjustment or passive adjustment. Way, dynamically adjust the bandwidth.

In an optional embodiment provided based on the embodiment of FIG. 2A, as shown in FIG. 3A, the above step 204 further includes the following steps. In this embodiment, the active adjustment mode is described.

Step 301: The first network device acquires the transceiver status information in the process of transmitting data by using the WLAN link.

The transceiver status information is used to indicate the status of transmitting and receiving data using the WLAN link. Optionally, the transceiver status information includes at least one of the following: a received signal strength, and a transmission success rate. The received signal strength indicates the signal strength of the data received by the first network device, and the first network device acquires the received signal strength according to the Received Signal Strength Indication (RSSI). The transmission success rate indicates the success rate of the first network device transmitting data to the second network device.

Step 302: If the sending and receiving state information meets the preset condition, the first network device adjusts the bandwidth of the WLAN link to the first bandwidth, and sends the first information frame to the second network device by using the first bandwidth.

The setting conditions of the foregoing preset conditions include at least one of the following: received signal strength, and transmission success rate. If the sending and receiving status information meets the preset condition, the first network device adjusts the bandwidth of the WLAN link; if the sending and receiving status information does not meet the preset condition, the first network device does not adjust the bandwidth of the WLAN link, and maintains the original bandwidth for data. transmission.

In addition, as already described above, the first network device records the bandwidth capability of the second network device, and the first bandwidth used is the type of bandwidth that the second network device can support. It is also described above that the bandwidth commonly used in the WLAN includes 1 MHz, 5 MHz, 10 MHz, 20 MHz, 40 MHz, 80 MHz, and 160 MHz, etc., and the first network device adjusts the bandwidth step by step according to the bandwidth division when adjusting the bandwidth, for example, currently The bandwidth is 10 MHz. If the first network device increases the bandwidth, the first bandwidth is 20 MHz. If the first network device lowers the bandwidth, the first bandwidth is 5 MHz.

In the embodiment of the present application, the first network device ensures the stability of the bandwidth adjustment by recording the bandwidth capability of the second network device and adjusting the bandwidth step by step to reduce the impact on the data transmission.

The first information frame is a message transmitted by the first network device and the second network device on the WLAN link, and the information frame may be a data frame or a management frame.

Optionally, if the sending and receiving state information meets the first preset condition, the first network device increases the bandwidth of the WLAN link; if the sending and receiving state information meets the second preset condition, the first network device lowers the WLAN link. bandwidth. If the sending and receiving state information does not meet the first preset condition or the second preset condition, the first network device does not adjust the bandwidth of the WLAN link, and maintains the original bandwidth for data transmission.

The first preset condition includes at least one of the following: the received signal strength is greater than the first signal strength threshold, and the transmit success rate is greater than the first success rate threshold. The second preset condition includes at least one of the following: the received signal strength is less than the second signal strength threshold, and the transmit success rate is less than the second success rate threshold. The first signal strength threshold is greater than the second signal strength threshold, and the first success threshold is greater than the second success threshold. The signal strength threshold and success rate threshold can be preset based on actual experience or experimental data. Illustratively, the first signal strength threshold is 80 dBm, the second signal strength threshold is 40 dBm, the first success rate is 90%, and the second success rate is 70%. The received signal strength of the first network device is 90 dBm, and the transmission success rate is 95%. The transmission and reception state information of the first network device meets the first preset condition, and the bandwidth of the WLAN link is increased.

Step 303: If the first network device receives the first acknowledgement signal corresponding to the first information frame sent by the second network device, the first network device determines to use the first bandwidth to transmit data.

After receiving the first information frame sent by the first network device by using the first bandwidth, the second network device sends a first acknowledgement signal to the first network device if the first data bandwidth is used for subsequent data transmission. The first acknowledgement signal is used to indicate that the second network device agrees to adjust the bandwidth of the WLAN link. The bandwidth used by the second network device to send the first acknowledgement signal is the same as the first bandwidth used by the first network device to send the first information frame.

In a possible implementation manner, after receiving the first information frame sent by the first network device, the second network device directly sends the first acknowledgement signal to the first network device. In another possible implementation manner, after receiving the first information frame sent by the first network device, the second network device detects whether the received signal strength of the first information frame is greater than a preset threshold, and if yes, Sending a first acknowledgement signal corresponding to the first information frame to the first network device, and if not, transmitting a first acknowledgement signal corresponding to the first information frame to the first network device. The preset threshold can be preset based on actual experience or experimental data. The second network device can ensure that the data sent by the first bandwidth adopted by the first network device can be correctly received by the second network device by detecting whether the received signal strength of the first information frame is greater than a preset threshold.

Optionally, if the first network device does not receive the first acknowledgement signal corresponding to the first information frame sent by the second network device, the first network device still uses the original bandwidth for data communication.

Optionally, the first acknowledgment signal is used to indicate that the second network device has correctly received the first information frame, and is used to indicate that the second network device agrees to adjust the bandwidth of the WLAN link.

Please refer to FIG. 3B, which exemplarily shows an interaction diagram of a bandwidth adjustment process. A WLAN link has been established between the first network device and the second network device, and data transmission is performed at a bandwidth of 20 MHz. The first network device transmits the data data_sn1000 in a bandwidth of 20 MHz. If the transmission fails, the first network device lowers the bandwidth to 10 MHz and retransmits the data data_sn1000 with a bandwidth of 10 MHz. After receiving the data data_sn1000 sent by the first network device in the 10 MHz bandwidth, if the second network device agrees to adjust the bandwidth from 20 MHz to 10 MHz, the acknowledgment signal ack_sn1000 is sent in the 10 MHz bandwidth, indicating that the second network device has correctly received the data data_sn1000. After receiving the acknowledgment signal ack_sn1000, the first network device performs data transmission with the second network device at a bandwidth of 10 MHz.

In the solution provided by the embodiment of the present application, the network device can dynamically adjust the bandwidth of the WLAN link according to the sending and receiving state information, and maintain a balance between the throughput requirement and the signal coverage requirement. Maximize throughput requirements while ensuring that WLAN links are not disconnected.

In another optional embodiment provided based on the embodiment of FIG. 2A, as shown in FIG. 4A, the above step 204 further includes the following steps. In this embodiment, the passive adjustment mode is described.

Step 401: The second network device acquires the sending and receiving state information in the process of transmitting data by using the WLAN link.

The transceiver status information is used to indicate the status of transmitting and receiving data using the WLAN link. Optionally, the transceiver status information includes at least one of the following: a received signal strength, and a transmission success rate. The received signal strength represents the signal strength of the data received by the second network device. The transmission success rate indicates the success rate of the second network device transmitting data to the first network device.

Step 402: If the sending and receiving state information meets the preset condition, the second network device adjusts the bandwidth of the WLAN link to the second bandwidth, and sends the second information frame to the first network device by using the second bandwidth.

For the bandwidth adjustment process of the second network device, refer to the bandwidth adjustment process of the first network device in the foregoing embodiment of FIG. 3A, which is not repeatedly described in this embodiment.

Step 403: If the first network device receives the second information frame sent by the second network device by using the second bandwidth, send a second acknowledgement signal corresponding to the second information frame to the second network device.

After receiving the second information frame sent by the second network device by using the second bandwidth, the first network device sends a second acknowledgement signal to the second network device if the second data bandwidth is used for subsequent data transmission. The second acknowledgement signal is used to indicate that the first network device agrees to adjust the bandwidth of the WLAN link. The bandwidth used by the first network device to send the second acknowledgment signal is the same as the second bandwidth used by the second network device to send the second information frame.

In a possible implementation, after receiving the second information frame sent by the second network device, the first network device sends a second acknowledgement signal directly to the second network device. In another possible implementation manner, after receiving the second information frame sent by the second network device, the first network device detects whether the received signal strength of the second information frame is greater than a preset threshold, and if yes, Sending a second acknowledgement signal corresponding to the second information frame to the second network device, and if not, transmitting a second acknowledgement signal corresponding to the second information frame to the second network device. The preset threshold can be preset based on actual experience or experimental data. The first network device can ensure that the data sent by the second bandwidth adopted by the second network device can be correctly received by the first network device by detecting whether the received signal strength of the second information frame is greater than a preset threshold.

Optionally, if the second network device does not receive the second acknowledgment signal corresponding to the second information frame sent by the first network device, the second network device still uses the original bandwidth for data communication.

Optionally, the second acknowledgment signal is used to indicate that the first network device has correctly received the second information frame, and is used to indicate that the first network device agrees to adjust the bandwidth of the WLAN link.

Please refer to FIG. 4B, which exemplarily shows an interaction diagram of a bandwidth adjustment process. A WLAN link has been established between the first network device and the second network device, and data transmission is performed with a bandwidth of 10 MHz. The second network device transmits the data data_sn1000 in a 10 MHz bandwidth. If the transmission fails, the second network device lowers the bandwidth to 5 MHz and retransmits the data data_sn1000 at a bandwidth of 5 MHz. After receiving the data data_sn1000 sent by the second network device in the 5 MHz bandwidth, the first network device sends the acknowledgment signal ack_sn1000 to the 5 MHz bandwidth if it agrees to adjust the bandwidth from 10 MHz to 5 MHz, indicating that the first network device has correctly received the data data_sn1000. After receiving the acknowledgment signal ack_sn1000, the second network device performs data transmission with the first network device at a bandwidth of 5 MHz.

The solution provided by the embodiment of the present application is described below through two examples.

Referring to FIG. 5, in an example, an application scenario in which the smartphone 51 is used to control the drone 52 is taken as an example. Different bandwidths are used at different distances to ensure that the operator can obtain a larger control range and recover the drone 52 in time. When the distance between the drone 52 and the smartphone 51 is less than 0.1 km, the HD video is transmitted using the 40 MHz bandwidth; when the distance between the drone 52 and the smartphone 51 becomes 0.1 km to 0.5 km, the smartphone 51. The bandwidth is adjusted according to the sending and receiving status information, and the bandwidth is reduced to 20 MHz to transmit the normal video. When the distance between the drone 52 and the smart phone 51 exceeds 0.5 km, the smart phone 51 further reduces the bandwidth according to the sending and receiving status information, and The bandwidth is reduced to 1 MHz, ensuring that control messages for controlling the drone 52 can be properly received by the drone 52. In the above manner, it is ensured that the control message transmission distance is further, the reliability is increased, and the accident situation caused by the control message loss is avoided.

Please refer to FIG. 6. In another example, an application scenario in which communication between two

smartphones

61 and 62 is performed is taken as an example. When the smart phone 61 is more than 1000 meters away from the smart phone 62, the text communication is performed using the 1 MHz bandwidth; when the smart phone 61 is 50 meters to 1000 meters away from the smart phone 62, the voice communication is performed using the 5 MHz bandwidth; when the smart phone 61 is away from the smart phone When 62 is less than 50 meters, video communication is performed using a 10 MHz bandwidth. In the above manner, different bandwidths are used at different distances, so that communication is performed by using appropriate communication methods.

The solution provided by the embodiment of the present application is introduced from the perspective of interaction between the first network device and the second network device. It can be understood that the network device (for example, the first network device, the second network device) includes corresponding hardware structures and/or software modules for performing the respective functions in order to implement the above functions. The embodiments of the present application can be implemented in a combination of hardware or hardware and computer software in combination with the elements of the examples and algorithm steps described in the embodiments disclosed in the application. Whether a function is implemented in hardware or computer software to drive hardware depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the technical solutions of the embodiments of the present application.

The embodiments of the present application may perform functional unit division on a network device (for example, a first network device and a second network device) according to the foregoing method example. For example, each functional unit may be divided according to each function, or two or more functions may be used. The functions are integrated in one processing unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit. It should be noted that the division of the unit in the embodiment of the present application is schematic, and is only a logical function division. In actual implementation, there may be another division manner.

In the case of employing an integrated unit, FIG. 7A shows a possible structural diagram of the network device involved in the above embodiment. The network device 700 includes a processing unit 702 and a communication unit 703. The processing unit 702 is configured to control and manage the actions of the network device 700. For example, when the network device 700 is the first network device, the processing unit 702 is configured to support the network device 700 to perform steps 201 to 204 in FIG. 2A, steps 301 to 303 in FIG. 3A, and/or to perform the description herein. Other steps of the technology. When the network device 700 is a second network device, the processing unit 702 is configured to support the network device 700 to perform steps 401 through 403 in FIG. 4A, and/or to perform other steps of the techniques described herein. The communication unit 703 is configured to support communication of the network device 700 with other network devices. The network device 700 may further include a storage unit 701 for storing program codes and data of the network device 700.

The processing unit 702 can be a processor or a controller, and can be, for example, a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), and an application-specific integrated circuit (Application-Specific). Integrated Circuit (ASIC), Field Programmable Gate Array (FPGA) or other programmable logic device, transistor logic device, hardware component, or any combination thereof. It is possible to implement or carry out the various illustrative logical blocks, modules and circuits described in connection with the present disclosure. The processor may also be a combination of computing functions, for example, including one or more microprocessor combinations, a combination of a DSP and a microprocessor, and the like. The communication unit 703 can be a communication interface, a transceiver, a transceiver circuit, etc., wherein the communication interface is a collective name and can include one or more interfaces, such as an interface between the first network device and the second network device. The storage unit 701 can be a memory.

When the processing unit 702 is a processor, the communication unit 703 is a communication interface, and the storage unit 701 is a memory, the network device involved in the embodiment of the present application may be the network device shown in FIG. 7B.

Referring to FIG. 7B, the network device 710 includes a processor 712, a communication interface 713, and a memory 711. Alternatively, network device 710 can also include a bus 714. The communication interface 713, the processor 712, and the memory 711 may be connected to each other through a bus 714. The bus 714 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (abbreviated). EISA) bus and so on. The bus 714 can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only one thick line is shown in Figure 7B, but it does not mean that there is only one bus or one type of bus.

The network device shown in FIG. 7A or 7B above may be the first network device or the second network device.

The steps of the method described in connection with the disclosure of the embodiments of the present application may be implemented in a hardware manner, or may be implemented by a processor executing software instructions. The software instructions may be composed of corresponding software modules, which may be stored in a random access memory (RAM), a flash memory, a read only memory (ROM), an erasable programmable read only memory ( Erasable Programmable ROM (EPROM), electrically erasable programmable read only memory (EEPROM), registers, hard disk, removable hard disk, compact disk read only (CD-ROM) or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor to enable the processor to read information from, and write information to, the storage medium. Of course, the storage medium can also be an integral part of the processor. The processor and the storage medium can be located in an ASIC. Additionally, the ASIC can be located in a network device. Of course, the processor and the storage medium can also exist as discrete components in the network device.

Those skilled in the art should appreciate that in one or more of the above examples, the functions described in the embodiments of the present application may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the functions may be stored in a computer readable medium or transmitted as one or more instructions or code on a computer readable medium. Computer readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one location to another. A storage medium may be any available media that can be accessed by a general purpose or special purpose computer.

The specific embodiments of the present invention have been described in detail with reference to the embodiments, technical solutions and advantages of the embodiments of the present application. It should be understood that the foregoing description is only The scope of the present invention is defined by the scope of the present invention, and any modifications, equivalents, improvements, etc., which are included in the embodiments of the present application, are included in the scope of protection of the embodiments of the present application.

Claims

A method for establishing a WLAN link of a wireless local area network, the method comprising:

The first network device broadcasts the probe request by using an initial bandwidth;

The first network device detects whether a probe response corresponding to the probe request sent by the second network device is received;

If the probe response is not received, the first network device uses the adjusted bandwidth broadcast probe request, and starts from the step of detecting whether the probe response corresponding to the probe request sent by the second network device is received. Executing; wherein the adjustment bandwidth refers to a bandwidth smaller than the bandwidth used last time;

And if the probe response is received, the first network device establishes a WLAN link with the second network device, where a bandwidth of the WLAN link is a bandwidth used when receiving the probe response.
The method according to claim 1, wherein the initial bandwidth is 20 MHz; and in the case that a probe response corresponding to the probe request transmitted using the initial bandwidth is not received, the adjustment bandwidth is 1 MHz.
The method of claim 1 further comprising:

Transmitting, by the first network device, the first bandwidth capability information to the second network device, and receiving the second bandwidth capability information sent by the second network device;

The first bandwidth capability information is used to indicate a bandwidth type supported by the first network device, and the second bandwidth capability information is used to indicate a bandwidth type supported by the second network device.
The method according to any one of claims 1 to 3, wherein after the first network device establishes a WLAN link with the second network device, the method further includes:

In the process of transmitting data by using the WLAN link, the first network device acquires the sending and receiving state information, where the sending and receiving state information is used to indicate a state in which data is sent and received by using the WLAN link;

If the sending and receiving state information meets the preset condition, the first network device adjusts the bandwidth of the WLAN link to the first bandwidth, and uses the first bandwidth to send the first information frame to the second network device;

If the first network device receives the first acknowledgement signal corresponding to the first information frame sent by the second network device, the first network device determines to use the first bandwidth to transmit data.
The method according to any one of claims 1 to 3, wherein after the first network device establishes a WLAN link with the second network device, the method further includes:

Sending, by the first network device, a second information frame that is sent by the second network device by using the second bandwidth, sending, by the second network device, a second acknowledgement signal corresponding to the second information frame; The second bandwidth is obtained by the second network device adjusting the bandwidth of the WLAN link.
A first network device, the first network device comprising: a processing unit and a communication unit;

The communication unit is configured to broadcast a probe request by using an initial bandwidth;

The processing unit is configured to detect whether a detection response corresponding to the probe request sent by the second network device is received;

The communication unit is further configured to: if the probe response is not received, adopt an adjusted bandwidth broadcast probe request, and the processing unit again receives, from the detecting, whether the probe request sent by the second network device is received The step of corresponding probe response begins to be performed; wherein the adjusted bandwidth refers to a bandwidth smaller than the bandwidth used last time;

The processing unit is further configured to establish a WLAN link with the second network device, if the probe response is received, where a bandwidth of the WLAN link is a bandwidth used when receiving the probe response. .
The network device according to claim 6, wherein the initial bandwidth is 20 MHz; and in the case that a probe response corresponding to the probe request transmitted by using the initial bandwidth is not received, the adjustment bandwidth is 1 MHz.
A network device according to claim 6, wherein

The communication unit is further configured to send first bandwidth capability information to the second network device, and receive second bandwidth capability information sent by the second network device;

The first bandwidth capability information is used to indicate a bandwidth type supported by the first network device, and the second bandwidth capability information is used to indicate a bandwidth type supported by the second network device.
A network device according to any one of claims 6 to 8, characterized in that

The processing unit is further configured to: acquire, in the process of transmitting data by using the WLAN link, the sending and receiving state information, where the sending and receiving state information is used to indicate a state in which data is sent and received by using the WLAN link;

The processing unit is further configured to: if the transceiver status information meets a preset condition, adjust a bandwidth of the WLAN link to a first bandwidth, and adopt, by using, the first bandwidth to the first The second network device sends the first information frame;

The processing unit is further configured to: if the communication unit receives the first acknowledgement signal corresponding to the first information frame sent by the second network device, determine to use the first bandwidth to transmit data.
A network device according to any one of claims 6 to 8, characterized in that

The communication unit is further configured to: if receiving the second information frame sent by the second network device by using the second bandwidth, send a second acknowledgement signal corresponding to the second information frame to the second network device The second bandwidth is obtained by the second network device adjusting the bandwidth of the WLAN link.
A computer storage medium, characterized in that the computer storage medium stores executable instructions for performing the method of any one of claims 1 to 5.