WO2014173120A1

WO2014173120A1 - Establishing method, station and system of relay link

Info

Publication number: WO2014173120A1
Application number: PCT/CN2013/087459
Authority: WO
Inventors: 杨绿溪; 王士玉; 杨讯
Original assignee: 华为技术有限公司
Priority date: 2013-04-25
Filing date: 2013-11-20
Publication date: 2014-10-30
Also published as: CN104125652A

Abstract

The embodiments of the present invention relate to an establishing method, a receiving station, a request station and a system of a relay link. The method comprises: the receiving station receives a first broadcast frame transmitted by the request station and a second broadcast frame transmitted by an access point, when the first broadcast frame and the second broadcast frame are both relay discovering request frames of the request station, and when the receiving station has been set as a relay type station, the receiving station transmits a relay discovering response frame to the request station, so that the request station determines whether to establish a relay relationship with the receiving station based on the relay discovering response frame. Therefore, the present invention completes the technical details of the request station transmitting the relay discovering request frame and receiving the relay discovering response frame, and achieves that the request station can transmit data to the access point (AP) by utilizing better channel conditions and high order MCS, which not only improve the data transmission rate, but also ensure the validity of the data transmission.

Description

Method, site and system for establishing a relay link The application is submitted to the Chinese Patent Office on April 25, 2013, and the application number is 201310146409.X, and the invention name is "the establishment method, site and system of the relay link". Priority of Chinese Patent Application, the entire contents of which is incorporated herein by reference. The present invention relates to the field of wireless communication technologies, and in particular, to a method, a station, and a system for establishing a relay link. BACKGROUND OF THE INVENTION With the rapid development of wireless communication technologies, in order to meet the demand for wireless service data, the IEEE 802. l lah standard emerges as the times require. The IEEE 802.l lah standard is mainly about the physical layer and media intervention control layer protocol, which defines a physical layer of orthogonal frequency division multiplexing and enhancements in media access control. Among them, an access point (Acs s Point, AP) in IEEE802.l lah can cover from 1 km to 2 km, and a Station (STA) farther from the AP sends data to the AP. It will experience a large channel fading. To this end, the concept of relay is introduced in the IEEE 802. l lah standard.

In the IEEE 802.11 lah standard, when there is a relay in the basic service set (BSS), STAs that are far away from the AP or whose power is limited can select the appropriate relay and establish a connection with it. When you need to send data to the AP, you only need to send the data to Relay, which is then forwarded to the AP by Relay.

FIG. 1 is a flowchart of a method for establishing a relay link provided by the prior art. As shown in the figure, the establishing method includes: first, the STA and the AP perform an association operation, and second, the STA sends a Relay discovery request frame and receives a Relay discovery response frame, and then the STA selects a Relay to establish a connection with, and establishes a connection with the Relay. Finally, the STA or the Relay reports the relay relationship between the two to the AP. The process of establishing a connection between the STA and the relay is: the STA sends a direct link to the Relay. A setup request frame of the Tunne led Di rect Link Setup (TDLS) is established. After receiving the setup response frame of the Relay response, the STA sends a setup confirmation frame of the TDLS to the relay. In addition, the establishment method is based on the establishment of a TDLS link method between existing STAs, but only corresponding changes have been made in some parts.

However, the above method only involves the general establishment process of the Relay link, and the necessary technical details are lacking in the STA sending the Relay discovery request frame and receiving the Relay discovery response frame, and how the STA selects the Relay part. At the same time, when multiple Relays receive the Relay Discovery Request frame and respond to the Relay Discovery Response frame, the multiple Relays may cause collision, rollback, etc. when accessing the channel, thereby increasing the waiting time of the STA, which is not conducive to saving. The transmit power of the STA. SUMMARY OF THE INVENTION Embodiments of the present invention provide a method, a site, and a system for establishing a relay link, to alleviate the lack of necessary technical details in the process of establishing a Relay link in the prior art, and when multiple relays are received When the Relay finds the request frame and responds to the Relay to find the response frame, the multiple Relays may cause collision or fallback when accessing the channel.

In a first aspect, an embodiment of the present invention provides a method for establishing a relay link, where the method includes: receiving, by a receiving station, a first broadcast frame sent by a requesting station and a second broadcast frame sent by an access point, where a second broadcast frame is a broadcast frame generated by the access point after receiving the first broadcast frame sent by the requesting station, where the receiving station and the requesting site are located in a coverage of the access point; If the first broadcast frame and the second broadcast frame are both a relay discovery request frame of the requesting site, and the receiving station is configured as a relay type site, sending a relay discovery response frame to the requesting station. And determining, by the requesting station, whether to establish a relay relationship with the receiving station according to the relay discovery response frame. .

In a first possible implementation, the first broadcast frame and the second broadcast frame are both a relay discovery request frame of the requesting site, and the receiving station is configured as a relay type site. Sending a relay discovery request frame to the requesting station includes: if the first broadcast frame and The second broadcast frame is a relay discovery request frame of the requesting site, and the receiving station is configured as the relay type site, and measures frame energy of the first broadcast frame; if the first broadcast The frame energy of the frame is greater than a preset energy threshold, and the relay discovery request frame is sent to the requesting station.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a second possible implementation, the first broadcast frame and the second broadcast frame are both the requesting site a relay discovery request frame, and the receiving station is configured as a relay type site, and sending the relay discovery request frame to the requesting station includes: relaying according to the first broadcast frame and the second broadcast frame The discovery indication field and the media access control MAC header determine that the first broadcast frame and the second broadcast frame are both relay discovery request frames of the requesting site, and when the receiving site is set as a relay type site, A relay discovery response frame is sent to the requesting site.

In a second aspect, an embodiment of the present invention provides a method for establishing a relay link, where the method includes: requesting a station to send a first broadcast frame to an access point, and according to the first Generating a second broadcast frame by the broadcast frame, and transmitting the second broadcast frame to a receiving station within the coverage of the access point; receiving a relay discovery response frame sent by the receiving station, and discovering according to the relay The response frame determines whether a relay relationship with the receiving station is established.

In a first possible implementation manner, a frame structure of the first broadcast frame and the second broadcast frame is the same, and a physical layer PHY header of the first broadcast frame and the second broadcast frame includes the middle Following the discovery indication field; the receiver address in the media access control MAC header of the first broadcast frame is the MAC address of the access point, the transmitter address is the MAC address of the requesting station, and the destination address is a broadcast address. The receiver address of the MAC header of the second broadcast frame is a broadcast address, the transmitter address is a MAC address of the access point, and the source address is a MAC address of the requesting station.

With reference to the second aspect or the first possible implementation manner of the second aspect, in a second possible implementation manner, the coverage of the access point includes multiple receiving sites, and the receiving the receiving site Sending a relay discovery response frame, and determining, according to the relay discovery response frame, whether to establish a relay relationship with the receiving site, including: receiving the multiple in a preset response time a relay discovery response frame sent by the receiving station; calculating a frame energy of each relay discovery response frame, and obtaining a calculation result after the calculating; selecting, from the calculation result, a receiving station corresponding to the maximum frame energy as the requesting site and The receiving site that establishes the relay relationship.

In a third aspect, an embodiment of the present invention provides a receiving station, where the station includes: a receiving unit, configured to receive a first broadcast frame sent by a requesting station, and a second broadcast frame sent by an access point, where the second a broadcast frame is a broadcast frame generated by the access point after receiving the first broadcast frame sent by the requesting station, where the receiving station and the requesting site are located within the coverage of the access point, and the The first broadcast frame and the second broadcast frame are transmitted to the first processing unit; the first processing unit is configured to receive the first broadcast frame and the second broadcast frame from the receiving unit, if The first broadcast frame and the second broadcast frame are both a relay discovery request frame of the requesting site, and the receiving station is configured as a relay type site, and sends a relay discovery response frame to the requesting station, where The requesting station determines whether to establish a relay relationship with the receiving station according to the relay discovery response frame.

In a first possible implementation manner, the first processing unit is further configured to: if the first broadcast frame and the second broadcast frame are both relay discovery request frames of the requesting site, and the receiving The station is configured as the relay type site, and measures frame energy of the first broadcast frame; if the frame energy of the first broadcast frame is greater than a preset energy threshold, sending the relay discovery request to the requesting station frame.

With reference to the third aspect or the first possible implementation manner of the third aspect, in a second possible implementation manner, the first processing unit is further configured to use, according to the first broadcast frame and the second broadcast The relay discovery indication field and the medium access control MAC header in the frame determine that the first broadcast frame and the second broadcast frame are both relay discovery request frames of the requesting site, and the receiving station is set to medium When the site is succeeded, a relay discovery response frame is sent to the requesting site.

In a fourth aspect, an embodiment of the present invention provides a requesting station, where the station includes: a sending unit, configured to send a first broadcast frame to an access point, and according to the first broadcast frame by using the access point Generating a second broadcast frame and transmitting to a receiving station within coverage of the access point And the processing unit is configured to receive a relay discovery response frame sent by the receiving station, and determine, according to the relay discovery response frame, whether to establish a relay relationship with the receiving station.

In a first possible implementation manner, a frame structure of the first broadcast frame and the second broadcast frame is the same, and a PHY header of the first broadcast frame and the second broadcast frame includes the relay discovery An indication field; a receiver address in the media access control physical layer MAC header of the first broadcast frame is a MAC address of the access point, a transmitter address is a MAC address of the requesting station, and a destination address is a broadcast address The receiver address of the MAC header of the second broadcast frame is a broadcast address, the transmitter address is a MAC address of the access point, and the source address is a MAC address of the requesting station.

With reference to the fourth aspect or the first possible implementation manner of the fourth aspect, in a second possible implementation, the coverage of the access point includes multiple receiving sites, and the processing unit is further used to Receiving a relay discovery response frame sent by the multiple receiving stations in a preset response time, calculating a frame energy of each relay discovery response frame, obtaining a calculation result after the calculation, and selecting a maximum from the calculation result The receiving station corresponding to the frame energy serves as a receiving station with which the requesting station establishes a relay relationship.

In a fifth aspect, an embodiment of the present invention provides a system for establishing a relay link, where the system includes: a site provided by the third invention, a site provided in the fourth aspect, and a coverage provided by the third invention. The site and the access point of the site provided in the fourth aspect.

By using the method for establishing a relay link, the receiving station, the requesting station, and the system, the receiving station receives the first broadcast frame sent by the requesting station and the second broadcast frame sent by the access point, and determines the The first broadcast frame and the second broadcast frame are both relay discovery request frames of the same requesting site, and when the receiving station is configured as a relay type site, sending a relay discovery response frame to the requesting site, when Receiving, by the requesting station, a relay discovery response frame sent by the receiving station, determining, according to the relay discovery response frame, whether to establish a relay relationship with the receiving station, thereby completing the requesting station to send a Relay discovery request frame and receiving Relay discovers the technical details of the response frame, enabling the requesting site to transmit the number to the AP using relatively good channel conditions and a high-order Modulation and Coding Scheme (MCS). According to this, not only the data transmission rate is improved, but also the correctness of data transmission is ensured. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a flowchart of a method for establishing a relay link provided by the prior art;

2 is a flowchart of a method for establishing a relay link according to Embodiment 1 of the present invention; FIG. 3 is a schematic diagram of a frame structure of a first broadcast frame according to Embodiment 2 of the present invention; FIG. 5 is a schematic diagram of a frame structure of a TDLS discovery request frame according to Embodiment 4 of the present invention; FIG. 7 is a schematic diagram of a frame structure of a TDLS discovery request frame according to Embodiment 6 of the present invention; FIG. 8 is a schematic diagram of a frame structure of a TDLS setup request frame according to Embodiment 7 of the present invention; FIG. 9 is a schematic diagram of a frame structure of a TDLS setup confirmation frame according to Embodiment 8 of the present invention; FIG. 11 is a flowchart of a method for establishing a relay link according to Embodiment 10 of the present invention; FIG. 12 is a flowchart of establishing a relay link according to Embodiment 11 of the present invention; FIG. 13 is a schematic diagram of a method for establishing a relay link according to Embodiment 12 of the present invention; FIG. 14 is a schematic diagram of a station according to Embodiment 13 of the present invention;

Figure 15 is a schematic diagram of a station according to Embodiment 14 of the present invention;

16 is a schematic diagram of a station provided in Embodiment 15 of the present invention;

Figure 17 is a schematic diagram of a station provided in Embodiment 16 of the present invention. The embodiments of the present invention provide a method, a station, and a system for establishing a relay link, where the station includes a receiving station and a requesting station, and the receiving station receives the first broadcast frame sent by the requesting station and the sending of the access point. a second broadcast frame, and determining that the first broadcast frame and the second broadcast frame are both relay discovery request frames of the same requesting site, and the receiving station is configured as a relay type site Sending a relay discovery response frame to the requesting station, and when the requesting site receives the relay discovery response frame sent by the receiving station, determining, according to the relay discovery response frame, whether to establish and the receiving site Following the relationship, the technical details of the request site sending the Relay discovery request frame and receiving the Relay discovery response frame are improved, and the requesting station can use the relatively good channel conditions and the high-order MCS to send data to the AP, which not only improves the data. The transmission rate also ensures the correctness of data transmission.

FIG. 2 is a flowchart of a method for establishing a relay link according to Embodiment 1 of the present invention. As shown in the figure, the embodiment of the present invention specifically includes the following steps:

Step 210: The receiving station receives the first broadcast frame sent by the requesting station and the second broadcast frame sent by the access point, where the second broadcast frame is that the access point receives the first broadcast sent by the requesting station. The broadcast frame generated after the frame, the receiving station and the requesting site are located within the coverage of the access point.

Specifically, each AP in IEEE802.l lah can cover a range of 1 to 2 kilometers and can cover multiple user sites, including a requesting site and a receiving site. In the embodiment of the present invention, the requesting site refers to a user site that sends a first broadcast frame, and the receiving site refers to a user site that receives the first broadcast frame and the second broadcast frame, and the receiving site may be one, or may For multiple. The requesting station is generally far away from the AP, and needs to send data to the AP through the receiving station as a relay, so that the requesting station can use the relatively good channel condition and the high-order MCS to send data to the AP, which not only improves the data transmission rate, It also guarantees the correctness of data transmission.

When the requesting station selects the relay station, generally, the receiving station closer to itself should be selected as the relay station, and the remote receiving station does not need to respond when receiving the first broadcast frame or the second broadcast frame. The selection method adopted is a selective response mechanism, that is, the receiving station responds not only when receiving the first broadcast frame but also when receiving the second broadcast frame.

The first broadcast frame is a Relay discovery request frame sent by the requesting station to the AP, and the second broadcast frame is a media access control of the received Relay discovery request frame after the AP receives the Relay discovery request frame sent by the requesting station. Media Acces s Control , MAC ) header is modified, The modified Relay Discovery Request frame obtained by the modification is broadcast to all user sites within its coverage. The requesting station sends the first broadcast frame to the AP by using a broadcast manner, so the receiving station can receive the first broadcast frame and the second broadcast frame.

The frame structure of the first broadcast frame and the frame structure of the second broadcast frame are similar to the TDLS discovery request frame in the prior art. The frame structure of the first broadcast frame, as shown in Figure 3. The frame structure of the frame structure of the second broadcast frame is as shown in FIG. The frame structure of the request frame is found by TDLS, as shown in Figure 5. 3 and FIG. 4, compared with FIG. 5, the difference is: setting the target address of the MAC header in the TDLS discovery request frame as a broadcast address, and modifying the TDLS originating site MAC address in the frame body to the Relay originating station MAC address. The address, TDLS response site MAC address is changed to Relay response site MAC address, and the Relay response site MAC address is set to the broadcast address. In the embodiment of the present invention, the PP originating site MAC address refers to the MAC address of the requesting site. As for the rest of the frame structure of the first broadcast frame and the second broadcast frame, for example, Log Link Control (LLC) is a sub-network access sub-network (Sub Network Access Protocol, SNAP) header and The MAC address (BSSID) of the station, etc., is the same as the TDLS discovery request frame, and will not be described in detail here.

As shown in FIGS. 3 and 4, the frame structure of the first broadcast frame and the frame structure of the second broadcast frame are the same. However, the address information in the MAC header of the first broadcast frame is different from the address information in the MAC header of the second broadcast frame. The MAC header contains four address fields, each of which is 6 bytes in length. These four address fields do not necessarily appear in the transmitted broadcast frame. The four address fields can indicate the transmitter address, receiver address, destination address, source address (ie, which station the frame originated from, possibly different from the transmitter address).

The receiver address in the MAC header of the first broadcast frame is the MAC address (BSSID) of the AP, the transmitter address is the MAC address of the requesting station, and the destination address is the broadcast address.

The receiver address in the MAC header of the second broadcast frame is the broadcast address, the transmitter address is the MAC address (BSSID) of the AP, and the source address is the MAC address of the requesting station.

Among them, the AP is also a kind of user site, but it is more powerful, therefore, requesting the MAC of the site. The address and the MAC address of the AP have the same nature, which can be understood as the exclusive unique serial number set at the factory, such as 00-23-5A-15-99-42. In addition, when the 48 bits of the address field are all 1, it is a broadcast address.

In addition, a Relay Discovery Indicator (RDI) field is added to the signaling field (S IG ) of the physical layer (Phys ica l Layer, PHY) header of the first broadcast frame and the second broadcast frame, and the length of the field is added. For lbi t. When RDI is 1, it indicates that the frame is a frame used in the Relay Di scovery phase. When RDI is 0, it indicates that the frame is a frame in other situations; or, when RDI is 0, it indicates This frame is used for the frame in the Relay Di scovery phase. When the RDI is 1, it indicates that the frame is a frame in other situations. The relay discovery indication field may also be represented by other methods, and is not described here again, as long as the request site and the receiving site have the same meanings indicated by the Relay Discovery indication field.

Step 220: If the receiving station determines that the first broadcast frame and the second broadcast frame are both relay discovery request frames of the same requesting site, and the receiving station is configured as a relay type site, to the requesting site And sending a relay discovery response frame, where the requesting station determines whether to establish a relay relationship with the receiving station according to the relay discovery response frame. In addition, when the first broadcast frame and the second broadcast frame are both relay discovery request frames of the same requesting site, and the receiving station is not a relay type site, discarding the first broadcast frame and the The second broadcast frame is described.

Specifically, in general, when the receiving station receives the first broadcast frame or the second broadcast frame, it first decodes to the MAC header portion, and determines whether to receive or demodulate the following information according to the receiver address or the destination address information. Because Relay is a newly introduced mechanism, the receiving station can directly obtain the RDI value when demodulating the signal. The RDI only indicates whether it is the relay discovery phase, and there is also a discovery response frame.

Determining, according to the first broadcast frame and the relay discovery indication field in the second broadcast frame, that the first broadcast frame and the second broadcast frame are both in a Relay discovery phase, and then according to the first broadcast frame. And determining, by the address information in the second broadcast frame MAC header, whether the first broadcast frame and the second broadcast frame are relay discovery request frames of the same requesting site, when determining the first The broadcast frame and the second broadcast frame are relay discovery request frames of the same requesting site, and when the receiving station that receives the first broadcast frame and the second broadcast frame is also set as a Relay site, directly to the The requesting site sends a relay discovery response frame. Among them, whether the receiving site is a Relay site or a non-Relay site, which is a supplementary function of the newly-produced user site, the user site can turn on or off the relay service of its own site according to requirements.

The method for determining, by the receiving station, that the first broadcast frame and the second broadcast frame are both the relay discovery request frames of the same requesting site is specifically described below:

(1) The RDI indication of lbi t in the signaling field SIG of the PHY Header of the PHY header of the first broadcast frame and the second broadcast frame indicates whether the transmitted frame is operating in the Relay discovery phase, for example, the receiving station is based on The RDI is 1 to know that the received broadcast frame belongs to the Relay discovery phase.

(2) In the Relay discovery phase, only one address in the Relay discovery request frame is set to the broadcast address, for example, all 1s, when the receiving station detects the broadcast address, it knows that the received broadcast frame is a Relay discovery request. frame.

(3) Comparing the address information of the first broadcast frame and the second broadcast frame. If the address information is the same, it indicates that the first broadcast frame and the second broadcast frame belong to the same requesting station.

Further, the step 220 further includes: when the receiving station determines that the first broadcast frame and the second broadcast frame are both a relay discovery request frame of the same requesting site, and the receiving station is set to the relay type The selective response mechanism adopted by the station is that the relay discovery response frame is not directly sent to the requesting station, but the frame energy of the received first broadcast frame is first measured, and the frame energy of the first broadcast frame is greater than the pre- When the energy threshold is set, the relay discovery request frame is sent to the requesting station. The description indicates that when the frame energy of the first broadcast frame is greater than the preset energy threshold, the distance between the requesting station and the receiving station is relatively close, and the receiving station is suitable as a relay station of the requesting station; when the frame energy of the first broadcast frame is not greater than When the preset energy threshold is used, it indicates that the distance between the requesting site and the receiving site is relatively long, and the receiving site is not suitable as a relaying site of the requesting site.

In addition, the structure of the Relay discovery response frame is similar to the structure of the TDLS discovery response frame. Relay The frame structure of the response frame is found. As shown in FIG. 6, the frame structure of the TDLS discovery response frame is as shown in FIG. In Figure 6, Re l ay initiates the site MAC address as the MAC address of the requesting site, and Relay responds to the site MAC address as the MAC address of the receiving site. The rest of the frame structure is similar to that of Figure 7, and will not be described in detail herein.

Further, after the step 220, the method further includes: receiving, by the receiving station, a TDLS setup request frame sent by the requesting station, and sending a TDLS setup confirmation frame to the requesting station, where the requesting station establishes an acknowledgement frame according to the TDLS. a relay relationship of the receiving station, and the receiving station sends, to the access point, report information that carries the requesting station and the receiving station as a relay relationship, where the access point learns the request The relay relationship between the site and the receiving site.

The frame structure of the TDLS establishment request frame is as shown in FIG. 8; the frame structure of the TDLS establishment confirmation frame is as shown in FIG. 9. The specific definition of these frame structures is prior art and will not be described in detail herein.

Therefore, the method for establishing a relay link provided by the embodiment of the present invention receives, by the receiving station, a first broadcast frame sent by the requesting station and a second broadcast frame sent by the access point, and determines the first broadcast frame and the The second broadcast frame is a relay discovery request frame of the same requesting site, and when the receiving station is configured as a relay type site, sending a relay discovery response frame to the requesting site, where the requesting site is used according to the The relay discovery response frame determines whether to establish a relay relationship with the receiving station, thereby perfecting the technical details of requesting the station to send a Rely discovery request frame and receiving a Rey discovery response frame, thereby realizing that the requesting station can utilize relatively Good channel conditions and high-order MCS transmit data to the AP, which not only improves the data transmission rate, but also ensures the correctness of data transmission.

FIG. 10 is a flowchart of a method for establishing a relay link according to Embodiment 9 of the present invention. As shown in the figure, the embodiment of the present invention specifically includes the following steps:

Step 101: A plurality of receiving stations receive a first broadcast frame sent by the requesting station and a second broadcast frame sent by the access point, where the second broadcast frame is sent by the access point to the requesting station. a broadcast frame generated after a broadcast frame, the plurality of receiving stations and the requesting station are all located Within the coverage of the access point.

Step 102: If multiple receiving stations determine that the first broadcast frame and the second broadcast frame are both relay discovery request frames of the same requesting site, and the receiving station is configured as a relay type site, the multiple Receiving, by the receiving station, a channel in a freely competitive manner in a preset response time, and when the receiving station acquires the channel in the preset response time, sending the channel to the requesting station by using the channel Following the discovery of the request frame, the requesting station determines whether to establish a relay relationship with the receiving station according to the relay discovery response frame. In addition, when the receiving station does not acquire the channel within the preset response time, the base station sends a relay discovery request frame to the requesting station.

The acquiring channel refers to being able to access the channel by using a contention method, and sending a relay discovery request frame to the requesting station, that is, the receiving station first detects whether the channel is idle, and if the channel is idle, randomly retreating after a certain time The requesting station sends a relay discovery request frame; if it is not idle, it waits for the channel to be idle, and after the channel is idle, it randomly sends back a certain time to send a relay discovery request frame to the requesting station. This channel access mechanism has been adopted in existing protocols.

Further, the step 102 further includes: if the multiple receiving stations determine that the first broadcast frame and the second broadcast frame are both relay discovery request frames of the same requesting site, and the receiving station is set to the middle The relay station may also obtain the channel energy of the first broadcast frame without first obtaining the channel by freely competing, and only the received frame energy of the first broadcast frame is greater than the pre-predetermined The receiving station of the set energy threshold sends a relay discovery request frame to the requesting station through a freely competitive manner acquisition channel within a preset response time, and the remaining receiving stations abandon sending a relay discovery request to the requesting station. frame.

The preset response time in the above step 102 is set in advance, or may be set by the AP according to its own situation, and then notified to each user site in the coverage of the AP. The preset response time can be started after the AP sends a second broadcast frame to the user site within its coverage.

The frame structure of the first broadcast frame in the embodiment of the present invention is as shown in FIG. 3. The frame structure of the frame structure of the second broadcast frame is as shown in FIG. Re lay finds the frame structure of the response frame, as shown in Figure 6. TDLS The frame structure of the request frame is established, as shown in FIG. 8; the frame structure of the TDLS establishment confirmation frame is as shown in FIG. 9. These frame structures have been described in detail in the embodiment shown in FIG. 2 and will not be described again here.

FIG. 11 is a flowchart of a method for establishing a relay link according to Embodiment 10 of the present invention. As shown in the figure, the embodiment of the present invention specifically includes the following steps:

Step 111: The requesting station sends a first broadcast frame to the access point, and generates a second broadcast frame according to the first broadcast frame by using the access point, and sends the second broadcast frame to the receiving station in the coverage of the access point. The second broadcast frame. The frame structure of the first broadcast frame and the second broadcast frame are the same, and the PHY headers of the first broadcast frame and the second broadcast frame include the relay discovery indication field; The receiver address in the MAC header is the MAC address of the access point, the transmitter address is the MAC address of the requesting station, and the destination address is a broadcast address; the receiver address in the MAC header of the second broadcast frame is broadcast The address, the transmitter address is the MAC address of the access point; the source address is the MAC address of the requesting site.

Specifically, in the embodiment of the present invention, the requesting site refers to a user site that sends a first broadcast frame, and the receiving site refers to a user site that receives the first broadcast frame and the second broadcast frame, and the receiving site may be one. It can also be multiple. The requesting station is generally far away from the AP, and needs to send data to the AP through the receiving station as a relay. After the requesting site and the AP are associated, if the requesting site needs to obtain the relay site, the first broadcast frame, that is, the Relay discovery request frame, needs to be sent to the AP, and the AP receives the Relay discovery request frame sent by the requesting site, and then receives the Relay finds that the MAC header of the request frame is modified, and broadcasts the modified Relay discovery request frame to all user sites within its coverage.

Step 112: The requesting station receives a relay discovery response frame sent by the receiving station, and determines whether to establish a relay relationship with the receiving station according to the relay discovery response frame.

Specifically, when the coverage of the access point includes multiple receiving sites, the requesting site may receive the relay discovery response frame sent by the multiple receiving sites, and the processing method for the received multiple relay discovery response frames is :

(1) Receiving a relay discovery response frame sent by multiple receiving stations within a preset response time. (2) calculating a frame energy of each relay discovery response frame, and obtaining a calculation result after the calculation; (3) selecting a receiving station corresponding to the maximum frame energy from the calculation result as a relay relationship between the requesting station and the requesting station; Receive site.

After the step 112, the method further includes: the requesting station sends a channel direct link setup TDLS setup request frame to the receiving station, and receives a TDLS setup acknowledgement frame sent by the receiving station, and establishes an acknowledgement frame according to the TDLS. A relay relationship with the receiving site. In addition, the requesting station sends, to the AP, the reporting information that carries the requesting station and the receiving station as a relay relationship, where the access point learns the relay relationship between the requesting station and the receiving station. .

The frame structure of the first broadcast frame in the embodiment of the present invention is as shown in FIG. 3. The frame structure of the frame structure of the second broadcast frame is as shown in FIG. Relay finds the frame structure of the response frame, as shown in Figure 6. The frame structure of the request frame is established by TDLS, as shown in FIG. 8; the frame structure of the confirmation frame is established by TDLS, as shown in FIG. These frame structures have been described in detail in the embodiment shown in FIG. 2 and will not be described again here.

Therefore, the method for establishing a relay link according to an embodiment of the present invention sends a first broadcast frame to an access point by using a requesting station, and generates a second broadcast frame according to the first broadcast frame by using the access point, and Transmitting, by the receiving station in the coverage of the access point, the second broadcast frame, receiving a relay discovery response frame sent by the receiving station, and determining whether to establish and receive according to the relay discovery response frame. The site relay relationship improves the technical details of the request site sending the Relay discovery request frame and receiving the Relay discovery response frame, so that the requesting station can use the relatively good channel conditions and the high-order MCS to send data to the AP, which not only improves The data transmission rate also ensures the correctness of data transmission.

FIG. 12 is a flowchart of a method for establishing a relay link according to Embodiment 11 of the present invention. As shown in the figure, the embodiment of the present invention specifically includes the following steps:

Step 120 is that the requesting station (STA1) sends a Relay Discovery Request frame and receives the Relay Discovery Response frame. Steps 121 through 128 are specific technical details of step 120.

Step 121: The requesting station (STA1) sends a Relay discovery request frame to the AP, that is, the first broadcast. Frame (Fl).

Step 122: The AP broadcasts the relay discovery request frame, that is, the second broadcast frame (F2).

Step 123: The receiving station (STA2) is set as a relay type station. When STA2 is set as a relay type station, step 125 is performed. When STA2 is set as a non-relay type station, step 124 is performed.

Step 124: The STA2 abandons receiving the first broadcast frame or the second broadcast frame.

Step 125: Determine whether the frame energy PFI of the first broadcast frame (F1) received by the STA2 is greater than a preset energy threshold Ρο. When the PFI is greater than Po, step 126 is performed; when the PFI is not greater than Po, step 128 is performed.

Step 126: Determine whether STA2 can access the channel within a preset response time. When STA2 accesses the channel within the preset response time, step 127 is performed. When STA2 cannot access the channel within the preset response time, Then step 128 is performed.

Step 127: The STA2 directly sends a relay discovery response frame to the STA1.

Step 128: STA2 does not send a relay discovery response frame to STA1.

FIG. 13 is a schematic diagram of a method for establishing a relay link according to Embodiment 12 of the present invention. As shown in the figure, the two vertical lines in the figure indicate the competition channel, the box above the horizontal line represents the first broadcast frame (F1) of the transmitted frame, and the second broadcast frame (F2), and the lower line indicates the reception of the broadcast frame, including The first broadcast frame and the second broadcast frame.

STA1 is a requesting site, STA2 is a regular site, that is, a non-relay type STA, and STA3 to STA7 are relaying sites. F1 is the Relay discovery request frame sent by STA1 to the AP; F2 is the Relay discovery request frame broadcast by the AP; F3 is the Relay discovery response frame that STA4 or STA5 responds; F4 is the TDLS setup request frame sent by STA1 to STA4. PFI indicates the frame energy of the received first broadcast frame (F1), and PQ is the preset energy threshold PO, and P4 and P5 are the energy of the relay discovery response frame that the received STA4 and STA5 respond to, respectively.

STA3 receives only the second broadcast frame (F2) of the Relay discovery request frame broadcast by the AP, but does not receive the first broadcast frame (F1) from the request frame sent by STA1, so STA3 does not send to STA1. Relay finds the response frame;

STA7 receives the Relay Discovery Request frame broadcasted by the AP, that is, the second broadcast frame (F2), and also receives the request frame sent by STA1, that is, the first broadcast frame (F1), but receives the frame energy of the first broadcast frame (F1). The PFI is smaller than the preset energy threshold PQ, so the STA7 does not send the Relay discovery response frame to the STA1;

The STA6 receives the Relay Discovery Request frame of the AP broadcast, that is, the second broadcast frame (F2), and also receives the request frame sent by the STA1, that is, the first broadcast frame (F1), and simultaneously receives the frame of the first broadcast frame (F1). The energy PFI is not less than the preset energy threshold PQ, but the relay discovery response frame is discarded from being sent to the STA1 because the channel cannot be struck in the preset response time (ie, the Response Time L imi t window);

Only STA4 and STA5 satisfy all the conditions and successfully send a Relay discovery response frame to STA1, and STA1 selects a better one as its own relay. Assuming that STA1 receives a large amount of response information from STA4, STA4 is selected as a relay station.

As can be seen from the figure, the mechanism reduces the number of responding sites, can help the requesting site to quickly select the appropriate relay site, and also saves the power consumption of the requesting site.

FIG. 14 is a schematic diagram of a station according to Embodiment 13 of the present invention. The station is a receiving station, and is used to perform a method for establishing a relay link provided by Embodiments 1 to 12 of the present invention. As shown in the figure, the embodiment of the present invention specifically includes: a receiving unit 141 and a first processing unit 142.

The receiving unit 141 is configured to receive a first broadcast frame sent by the requesting station and a second broadcast frame sent by the access point, where the second broadcast frame is that the access point receives the first broadcast sent by the requesting station a broadcast frame generated after the frame, the receiving station and the requesting station are located in the coverage of the access point, and the first broadcast frame and the second broadcast frame have been transmitted to the first processing unit 142; The first processing unit 142 is configured to receive the first broadcast frame and the second broadcast frame from the receiving unit 141, if the first broadcast frame and the second broadcast frame are both in the requesting station Following the discovery request frame, and the receiving station is configured as a relay type site, and sending a relay discovery response frame to the requesting station, where the requesting station uses the relay to find a response frame. Determining whether to establish a relay relationship with the receiving site.

The frame structure of the first broadcast frame and the second broadcast frame is the same, and the PHY header of the first broadcast frame and the second broadcast frame includes the relay discovery indication field; the first broadcast The receiver address in the MAC header of the frame is the MAC address of the access point, the transmitter address is the MAC address of the requesting station, the destination address is a broadcast address, and the receiver address of the MAC header of the second broadcast frame For the broadcast address, the transmitter address is the MAC address of the access point, and the source address is the MAC address of the requesting site.

Further, the first processing unit 142 is further configured to: if the first broadcast frame and the second broadcast frame are both a relay discovery request frame of the requesting site, and the receiving station is set to be the middle And determining, by the relay station, a frame energy of the first broadcast frame; if the frame energy of the first broadcast frame is greater than a preset energy threshold, sending the relay discovery request frame to the requesting station. .

Further, the first processing unit 142 is further configured to determine the first broadcast frame and the second broadcast according to the relay discovery indication field and the MAC header in the first broadcast frame and the second broadcast frame. The frame is a relay discovery request frame of the requesting station, and when the receiving station is set as a relay type site, a relay discovery response frame is sent to the requesting station.

Further, the coverage of the access point includes a plurality of receiving sites, and the first processing unit 142 is further configured to acquire, by using the freely competitive manner, the channels by the multiple receiving stations in a preset response time. Sending, by the receiving station, a relay discovery request frame to the requesting station, when the receiving station acquires the channel in the preset response time, when the receiving station is in the preset response time If the channel is not acquired, the relay discovery request frame is sent to the requesting station.

Further, the receiving station provided by the embodiment of the present invention further includes: a second processing unit 143 and a sending unit 144.

The second processing unit 143 is configured to receive a channel direct link setup TDLS setup request frame sent by the requesting station, and send a TDLS setup acknowledgement frame to the requesting station, where the requesting station establishes an acknowledgement frame according to the TDLS. Relay relationship with the receiving station; sending unit 144, configured to send, to the access point, report information that carries the requesting station and the receiving station as a relay relationship, where the access point learns a relay relationship between the requesting station and the receiving station. .

In addition, the receiving station provided by the embodiment of the present invention further includes: a third processing unit 144. The third processing unit 144 is configured to discard the first broadcast frame and the location when the first broadcast frame and the second broadcast frame are both relay discovery request frames, and the receiving station is not a relay type site. The second broadcast frame is described.

Therefore, the receiving station provided by the embodiment of the present invention receives the first broadcast frame sent by the requesting station and the second broadcast frame sent by the access point, and determines that the first broadcast frame and the second broadcast frame are the same a relay discovery request frame of a requesting station, and when the receiving station is configured as a relay type site, sending a relay discovery response frame to the requesting station, where the requesting station determines, according to the relay discovery response frame Whether to establish a relay relationship with the receiving site, thereby perfecting the technical details of requesting the site to send a Relay discovery request frame and receiving a Relay discovery response frame, realizing that the requesting site can utilize relatively good channel conditions and high-order MCS Sending data to the AP not only improves the data transmission rate, but also ensures the correctness of the data transmission.

FIG. 15 is a schematic diagram of a station according to Embodiment 14 of the present invention. The site is a requesting site, and is used to perform a method for establishing a relay link provided by Embodiments 1 to 12 of the present invention. As shown in the figure, the embodiment of the present invention specifically includes: a sending unit 151 and a processing unit 152.

The sending unit 151 is configured to send a first broadcast frame to the access point, and generate, by using the access point, a second broadcast frame according to the first broadcast frame, and send to a receiving station in a coverage range of the access point. The second broadcast frame; the processing unit 152 is configured to receive a relay discovery response frame sent by the receiving station, and determine, according to the relay discovery response frame, whether to establish a relay relationship with the receiving station.

The frame structure of the first broadcast frame and the second broadcast frame is the same, and the PHY header of the first broadcast frame and the second broadcast frame includes the relay discovery indication field; the first broadcast The receiver address in the MAC header of the frame is the MAC address of the access point, and the transmitter address is a MAC address of the requesting site, the destination address is a broadcast address; a receiver address of the MAC header of the second broadcast frame is a broadcast address, a transmitter address is a MAC address of the access point; and a source address is the requesting site MAC address.

Further, the coverage of the access point includes a plurality of receiving stations, and the processing unit 152 is further configured to receive, by using the preset response time, a relay discovery response frame sent by the multiple receiving stations, and calculate each The relay finds the frame energy of the response frame, and obtains the calculation result after the calculation, and selects the receiving station corresponding to the maximum frame energy from the calculation result as the receiving station with which the requesting station establishes a relay relationship.

Further, the processing unit 152 is further configured to send a channel direct link setup TDLS setup request frame to the receiving station, and receive a TDLS setup acknowledgement frame sent by the receiving station, and establish an acknowledgement frame according to the TDLS establishment. Determining a relay relationship of the receiving station, and transmitting, to the access point, the upper information carrying the requesting station and the receiving station as a relay relationship, where the access point learns the requesting site and the Receive the relay relationship of the site.

Therefore, the requesting station provided by the embodiment of the present invention sends a first broadcast frame to the access point, and generates a second broadcast frame according to the first broadcast frame by using the access point, and sends the second broadcast frame to the access point. Receiving, by the receiving station in the coverage, the second broadcast frame, receiving a relay discovery response frame sent by the receiving station, and determining, according to the relay discovery response frame, whether to establish a relay relationship with the receiving station, thereby improving The technical details of the request site sending the Relay discovery request frame and receiving the Relay discovery response frame enable the requesting site to transmit data to the AP using relatively good channel conditions and high-order MCS, which not only improves the data transmission rate, but also improves the data transmission rate. The correctness of data transmission is guaranteed.

Figure 16 is a schematic diagram of a station provided in Embodiment 15 of the present invention. The site 160 is a requesting station 160 for performing a method for establishing a relay link according to the first embodiment to the twelfth embodiment of the present invention. As shown in the figure, the embodiment of the present invention specifically includes: a receiving station port 161, a processor 162, and a memory 163. The receiving station bus 164 is used to connect the receiving station port 161, the processor 162, and the memory 163. The receiving site port 161 is used to connect to the AP and the requesting node. The receiving site and the requesting site are both located within the coverage of the access point.

The memory 163 may be a persistent storage such as a hard disk drive and a flash memory having a software module and a device driver therein. The software modules are capable of executing various functional modules of the above described methods of the present invention; the device drivers can be network and interface drivers.

At startup, these software components are loaded into memory 163, which is then accessed by processor 162 and performs the method of establishing the relay link provided by embodiments 1 through 12 of the present invention.

Figure 17 is a schematic diagram of a station provided in Embodiment 16 of the present invention. The station 170 is a requesting station 170 for performing a method for establishing a relay link according to the first embodiment to the twelfth embodiment of the present invention. As shown in the figure, the embodiment of the present invention specifically includes: The embodiment of the present invention specifically includes a requesting site port 171, a processor 172, and a memory 173. The requesting site bus 174 is used to connect the requesting site port 171, the processor 172, and the memory 173.

The requesting site port 171 is used to connect to the AP and the receiving site. Both the receiving site and the requesting site are located within the coverage of the access point.

The memory 173 may be a persistent storage such as a hard disk drive and a flash memory having a software module and a device driver therein. The software modules are capable of executing various functional modules of the above described methods of the present invention; the device drivers can be network and interface drivers.

At startup, these software components are loaded into memory 173 and then accessed by processor 172 and the method of establishing the relay link provided by embodiments 1 through 12 of the present invention is performed.

The embodiment of the present invention further provides a system for establishing a relay link, the system comprising: the receiving station provided in Embodiment 14 of the present invention, the requesting site provided in Embodiment 15 of the present invention, and the receiving the receiving station and The access point of the requesting station; or the receiving station provided by Embodiment 16 of the present invention, the requesting station provided by Embodiment 17 of the present invention, and the access point covering the receiving station and the requesting station. A person skilled in the art should further appreciate that it is described in conjunction with the embodiments disclosed herein. The unit and algorithm steps of the various examples can be implemented in electronic hardware, computer software, or a combination of both. In order to clearly illustrate the interchangeability of hardware and software, various features have been generally described in terms of function in the above description. Example composition and steps. Whether these functions are performed in hardware or software 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 particular application, but such implementation should not be considered to be beyond the scope of the present invention.

The steps of a method or algorithm described in connection with the embodiments disclosed herein can be implemented in hardware, a software module executed by a processor, or a combination of both. Software modules can be placed in random access memory (RAM), memory, read only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or technology Any other form of storage medium known.

The above described embodiments of the present invention are further described in detail, and the embodiments of the present invention are intended to be illustrative only. The scope of the protection, any modifications, equivalents, improvements, etc., made within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

Rights request

1. A method for establishing a relay link, characterized in that the method includes: the receiving station receives a first broadcast frame sent by the requesting station and a second broadcast frame sent by the access point, and the second broadcast frame is The access point generates a broadcast frame after receiving the first broadcast frame sent by the requesting site, and the receiving site and the requesting site are located within the coverage of the access point;

If both the first broadcast frame and the second broadcast frame are relay discovery request frames of the requesting site, and the receiving site is set as a relay-type site, send a relay discovery response frame to the requesting site. , used by the requesting station to determine whether to establish a relay relationship with the receiving station according to the relay discovery response frame.

2. The method for establishing a relay link according to claim 1, wherein if the first broadcast frame and the second broadcast frame are both relay discovery request frames of the requesting site, And the receiving site is set as a relay site, and sending a relay discovery request frame to the requesting site includes:

If the first broadcast frame and the second broadcast frame are both relay discovery request frames of the requesting station, and the receiving station is set to the relay type station, measure the frame of the first broadcast frame energy;

If the frame energy of the first broadcast frame is greater than the preset energy threshold, the relay discovery request frame is sent to the requesting station.

3. The method for establishing a relay link according to claim 1 or 2, wherein if both the first broadcast frame and the second broadcast frame are of the requesting site, Following the discovery request frame, and the receiving site is set as a relay site, sending the relay discovery request frame to the requesting site includes:

Determine that both the first broadcast frame and the second broadcast frame are of the requesting station according to the relay discovery indication field and the media access control MAC header in the first broadcast frame and the second broadcast frame. Following the discovery request frame, and the receiving station is set as a relay type station, the requesting station The node sends a relay discovery response frame.

4. The method for establishing a relay link according to claim 3, wherein the first broadcast frame and the second broadcast frame have the same frame structure, and the first broadcast frame and the second broadcast frame have the same frame structure. The PHY header of the broadcast frame includes the relay discovery indication field; the receiver address in the MAC header of the first broadcast frame is the MAC address of the access point, and the transmitter address is the MAC address of the requesting site, The destination address is the broadcast address; the receiver address in the MAC header of the second broadcast frame is the broadcast address, the transmitter address is the MAC address of the access point, and the source address is the MAC address of the requesting site.

5. The method for establishing a relay link according to any one of claims 1 to 4, characterized in that, the coverage of the access point includes multiple receiving sites, and if the first broadcast frame and the second broadcast frame are both relay discovery request frames of the requesting site, and the receiving site is set as a relay type site. Sending the relay discovery request frame to the requesting site includes:

The multiple receiving stations acquire the channel through free competition within the preset response time. When the receiving station acquires the channel within the preset response time, the channel is used to send the channel to the The requesting station sends a relay discovery request frame. When the receiving station fails to obtain the channel within the preset response time, it gives up sending the relay discovery request frame to the requesting station.

6. The method for establishing a relay link according to any one of claims 1 to 5, characterized in that, after sending a relay discovery request frame to the requesting site, it further includes:

Receive a channel direct link establishment TDLS establishment request frame sent by the requesting site, and send a TDLS establishment confirmation frame to the requesting site, so that the requesting site establishes a connection with the receiving site based on the TDLS establishment confirmation frame. succession relationship;

Reporting information carrying a relay relationship between the requesting site and the receiving site is sent to the access point, so that the access point learns the relay relationship between the requesting site and the receiving site.

7. The method for establishing a relay link according to claim 1, wherein if both the first broadcast frame and the second broadcast frame are relay discovery requests of the requesting site, frame, and the receiving site is set as a relay site, sending a relay discovery response frame to the requesting site, further including:

When the first broadcast frame and the second broadcast frame are both relay discovery request frames, and the receiving station is not a relay-type station, the first broadcast frame and the second broadcast frame are discarded.

8. A method for establishing a relay link, characterized in that the method includes:

Requesting the station to send a first broadcast frame to an access point, generating a second broadcast frame based on the first broadcast frame through the access point, and sending the third broadcast frame to a receiving station within the coverage of the access point. 2 broadcast frames;

Receive the relay discovery response frame sent by the receiving site, and determine whether to establish a relay relationship with the receiving site based on the relay discovery response frame.

9. The method for establishing a relay link according to claim 8, wherein the first broadcast frame and the second broadcast frame have the same frame structure, and the first broadcast frame and the second broadcast frame have the same frame structure. The physical layer PHY header of the broadcast frame includes the relay discovery indication field; the receiver address in the media access control MAC header of the first broadcast frame is the MAC address of the access point, and the transmitter address is the The MAC address of the requesting site, the destination address is the broadcast address; the receiver address in the MAC header of the second broadcast frame is the broadcast address, and the transmitter address is the MAC address of the access point; the source address is the requesting site MAC address.

10. The method for establishing a relay link according to claim 8 or 9, wherein the coverage of the access point includes multiple receiving sites, and the receiving of the relay discovery sent by the receiving site response frame, and determining whether to establish a relay relationship with the receiving site based on the relay discovery response frame, including:

Receive relay discovery response frames sent by the multiple receiving stations within the preset response time; calculate the frame energy of each relay discovery response frame, and obtain the calculation result after the calculation; select the largest frame from the calculation result The receiving station corresponding to the energy serves as the receiving station with which the requesting station establishes a relay relationship.

11. The method for establishing a relay link according to claim 10, characterized in that: After selecting the receiving station corresponding to the maximum frame energy from the calculation result as the receiving station with which the requesting station establishes a relay relationship, it also includes:

Send a channel direct link establishment TDLS establishment request frame to the receiving site, and receive a TDLS establishment confirmation frame sent by the receiving site;

Establish a relay relationship with the receiving site according to the TDLS establishment confirmation frame;

12. A site, characterized in that the site includes:

A receiving unit, configured to receive a first broadcast frame sent by the requesting station and a second broadcast frame sent by the access point, where the second broadcast frame is when the access point receives the first broadcast sent by the requesting station. A broadcast frame generated after the frame, the receiving station and the requesting station are located within the coverage of the access point, and the first broadcast frame and the second broadcast frame have been transmitted to the first processing unit;

A first processing unit configured to receive the first broadcast frame and the second broadcast frame from the receiving unit, if both the first broadcast frame and the second broadcast frame are relays of the requesting site Discovery request frame, and the receiving site is set as a relay site, and sends a relay discovery response frame to the requesting site, so that the requesting site determines whether to establish communication with the receiving site based on the relay discovery response frame. relay relationship.

13. The site according to claim 12, wherein the first processing unit is further configured to: if both the first broadcast frame and the second broadcast frame are relay discovery requests of the requesting site frame, and the receiving station is set as the relay type station, measures the frame energy of the first broadcast frame; if the frame energy of the first broadcast frame is greater than the preset energy threshold, sends to the requesting station The relay discovery request frame.

14. The station according to claim 12 or 13, characterized in that, the first processing unit is further configured to detect the relay discovery indication field and media according to the relay discovery indication field and media in the first broadcast frame and the second broadcast frame. The access control MAC header determines that the first broadcast frame and the second broadcast frame are both the request When the receiving station is configured as a relay-type station, a relay discovery response frame is sent to the requesting station.

15. The station according to claim 14, characterized in that, the frame structures of the first broadcast frame and the second broadcast frame are the same, and the PHY headers of the first broadcast frame and the second broadcast frame include The relay discovery indication field; The receiver address in the MAC header of the first broadcast frame is the MAC address of the access point, the transmitter address is the MAC address of the requesting site, and the destination address is the broadcast address; The receiver address in the MAC header of the second broadcast frame is the broadcast address, the transmitter address is the MAC address of the access point, and the source address is the MAC address of the requesting site.

16. The site according to any one of claims 12 to 15, characterized in that, the coverage of the access point includes multiple receiving sites, and the first processing unit is also used for the multiple receiving sites. The channel is acquired through free competition within the preset response time. When the receiving station acquires the channel within the preset response time, the channel is used to send a relay discovery to the requesting station. request frame, when the receiving station does not obtain the channel within the preset response time, it gives up sending the relay discovery request frame to the requesting station.

17. The site according to any one of claims 12 to 15, characterized in that the site further includes:

The second processing unit is configured to receive the channel direct link establishment TDLS establishment request frame sent by the requesting site, and send a TDLS establishment confirmation frame to the requesting site, so that the requesting site establishes the channel direct link establishment according to the TDLS establishment confirmation frame. a relay relationship with said receiving site;

A sending unit, configured to send reporting information carrying a relay relationship between the requesting site and the receiving site to the access point, so that the access point can learn the relay relationship between the requesting site and the receiving site. successor relationship.

18. The site according to claim 12, characterized in that, the site further includes: a third processing unit, configured to: when the first broadcast frame and the second broadcast frame are both relay discovery request frames, And when the receiving station is not a relay-type station, the first broadcast frame and the second broadcast frame are discarded.

19. A site, characterized in that the site includes:

A sending unit, configured to send a first broadcast frame to an access point, generate a second broadcast frame according to the first broadcast frame through the access point, and send it to a receiving site within the coverage of the access point. The second broadcast frame;

A processing unit configured to receive a relay discovery response frame sent by the receiving site, and determine whether to establish a relay relationship with the receiving site based on the relay discovery response frame.

20. The station according to claim 19, characterized in that, the frame structures of the first broadcast frame and the second broadcast frame are the same, and the PHY headers of the first broadcast frame and the second broadcast frame include the relay discovery indication field; the receiver address in the media access control physical layer MAC header of the first broadcast frame is the MAC address of the access point, and the transmitter address is the MAC address of the requesting site, The destination address is the broadcast address; the receiver address in the MAC header of the second broadcast frame is the broadcast address, and the transmitter address is the MAC address of the access point; and the source address is the MAC address of the requesting site.

21. The site according to claim 19 or 20, characterized in that the coverage of the access point includes multiple receiving sites, and the processing unit is further configured to receive the multiple receiving sites within a preset response time. For each relay discovery response frame sent by the receiving station, calculate the frame energy of each relay discovery response frame, obtain the calculation result after the calculation, and select the receiving station corresponding to the maximum frame energy from the calculation result as the requesting station The receiving site with which a relay relationship is established.

22. The site according to claim 21, wherein the processing unit is further configured to send a channel direct link establishment TDLS establishment request frame to the receiving site, and receive a TDLS establishment confirmation frame sent by the receiving site. , establish a relay relationship with the receiving site according to the TDLS establishment confirmation frame, and send to the access point information carrying the relay relationship between the requesting site and the receiving site, for the The access point learns the relay relationship between the requesting site and the receiving site.

23. A system for establishing a relay link, characterized in that the method includes: the site according to claims 12 to 18, the site according to claims 19 to 22, and