CN106572489B

CN106572489B - One kind being based on the associated access of more BSS and transmission method

Info

Publication number: CN106572489B
Application number: CN201610957479.7A
Authority: CN
Inventors: 杨懋; 李波; 姬励; 闫中江
Original assignee: Northwest University of Technology
Current assignee: Northwest University of Technology
Priority date: 2016-11-03
Filing date: 2016-11-03
Publication date: 2019-11-05
Anticipated expiration: 2036-11-03
Also published as: CN106572489A

Abstract

The present invention provides a kind of methods based on more BSS associated access and transmission, it is related to field of communication technology, cell edge node carries out more association process to main AP request first, with from AP be associated or first be associated from AP after reinform main AP, keep out of the way simultaneously secondly based on EDCA mechanism, and reply main AP and the resource request frame from AP, and orthogonal frequency-time multiple access uplink is performed by the triggering frame scheduling of each AP, or TF-R is triggered by each AP and forms OFDMA random access, last cell edge node can start association handoff procedure, the present invention uses the associated access of more BSS and transmission method, solve Cell Edge User fairness poor, access and transmission plan are associated with using more BSS, promote the property of edge customer access and data transmission Can, it ensures the access and transmission quality of Cell Edge User, solves the problems, such as Cell Edge User by neighboring community's larger interference.

Description

One kind being based on the associated access of more BSS and transmission method

Technical field

The present invention relates to field of communication technology, the access of especially a kind of WLAN and transmission method.

Background technique

The media of 802.11 WLAN of IEEE (Wireless Local Area Networks, WLAN) default are visited Ask that control (Multiple Access Control, MAC) agreement is that there is the carrier sense multiple of conflict avoidance function to access (Carrier Sense Multiple Access with Collision Avoidance, CSMA/CA) agreement.The agreement In, several transmitting stations (station, STA) compete the broadcast channel right to use by specified rule, so that certain website is possible to and it The transmission data of his dispatching station clash, and not only channel resource are brought to waste, and also result in the throughput degradation and packet of network Average transmission delay increases.Especially next generation wlan suffers from larger interference towards highly dense scene, Cell Edge User, Therefore, it is difficult to obtain the channel right to use, and transmission rate is lower.To ensure fairness, need to try to promote Cell Edge User Access and data transmission quality.As capacity of equipment is constantly promoted, node has while listening to the ability of multiple channels, this is just For the fairness problem of Cell Edge User more bases are provided, solves existing ask to develop more methods Topic.

Summary of the invention

For overcome the deficiencies in the prior art, the present invention is directed to be connect using multiple cell is associated based under highly dense scene Enter and transmission method, solves existing 802.11 WLAN of IEEE and lack the means for promoting edge customer access and data transmission, it is small Area edge user suffers from neighboring community's larger interference, so that the problem that fairness is poor, promotes edge customer and access sum number According to the performance of transmission.

Core of the invention content mainly includes three parts, i.e. uplink process, downlink process and main association handoff procedure. Firstly, cell edge node cannot be serviced preferably for a long time by larger interference or positioned at cell edge experiencing itself Afterwards, more association process are carried out to primary wireless access points (access point, AP) request, and is associated from AP or first and from AP Main AP is reinformed after being associated；Secondly, accessing (Enhanced Distributed based on enhanced distributed coordination Channel Access, EDCA) mechanism is kept out of the way simultaneously in main plot and from cell, and replys main AP and from AP's Resource request (resource request, RR) frame, such as triggering-resource request frame (trigger frame-resource Request, TF-RR), and orthogonal frequency can be performed by the scheduling of the trigger frame (trigger frame, TF) of each AP Multiple access accesses (Orthogonal Frequency Division Multiple Access, OFDMA) uplink, Huo Zhetong It crosses each AP triggering TF-R and forms OFDMA random access；Finally, the discovery of cell edge node is in the long term, certain is from cell Access and transmission performance are better than main plot, can start association handoff procedure.

The detailed implementation steps of the technical solution adopted by the present invention to solve the technical problems are as follows:

Step 1: Cell Edge User node A arbitrarily selects the following two kinds implementation when carrying out more associations:

Implementation 1 is when Cell Edge User node A is in T₁Average interference in time is greater than defined interference threshold, Or T₁When average throughput is lower than defined throughput threshold in time, the interference threshold, throughput threshold and T₁By 802.11 agreement of the WLAN regulation for supporting multi-connection sends more associations to primary wireless access points AP (access point) After initialization frame MA-INIT (Multi-associate initialization), main AP receive more association initialization frames, More association initialization, which are returned, to node A agrees to frame MA-INIT-ACK (Multi-associate initialization Acknowledgement) or more association initialization disagree frame MA-INIT-NAK (Multi-associate Initialization not acknowledgement), if node A receives MA-INIT-ACK, node A listens to multiple letters Road, and multi-connection application frame MA-Req (multi- is sent from AP to the multiple of other cells except node A cell subjected Access-request), no matter whether the multiple main channel from AP identical, MA-Req multiple channels simultaneously send or Successively send on each channel respectively；After node A sends MA-Req frame, according to 802.11 agreement of WLAN, it is not All MA-Req frames that node A transmission can be all received from AP, received from AP MA-Req frame slave AP be known as it is to be selected from AP, to From AP after receiving MA-Req frame, Xiang Jiedian A returns to multi-connection application and agrees to frame MA-Req-ACK (multi-access- for choosing Request acknowledgement) or multi-connection application reject frame MA-Req-NAK (multi-access-request not acknowledgement)；If node A receives the MA-Req-ACK frame to be selected from AP, MA-Req- is sent to node A The to be selected of ACK frame forms incidence relation from AP and node A, i.e. node A is sending the to be selected from AP of MA-Req-ACK frame to node A Upper registration, Xiang Jiedian A send the to be selected of MA-Req-ACK frame and provide service from AP for node A, are transferred to step 2 later；

If node A does not receive the ACK of main AP or do not receive any one MA-Req-ACK from AP, abandon more Basic service set BSS (Basic Service Set) is associated with process；

Implementation 2 is Cell Edge User node A in T₁Average interference in time is greater than defined interference threshold, or Person T₁When average throughput is lower than defined throughput threshold in time, the interference threshold and throughput threshold and T₁By propping up 802.11 agreement of the WLAN regulation for holding multi-connection listens to multiple channels and sends multi-connection application frame from AP to multiple MA-Req, no matter main AP and main channel from AP it is whether identical, MA-Req sends simultaneously in multiple channels or successively exists respectively Each channel is sent；Frame MA-Req-ACK or reject frame MA-Req- is agreed in the slave AP selection for receiving the MA-Req frame of node A transmission NAK multi-connection application；If node A receives the MA-Req-ACK returned more than or equal to 1 AP, multi-connection application agreement is sent Whether frame MA_Rpt (multi-associate-report) informs more association results to main AP, that is, inform to succeed and establish with from AP Association after main AP receives MA_Rpt frame, returns to multi-connection request and agrees to acknowledgement frame MA_Rpt ACK frame (multi- Associate-report acknowledgement) confirmation, be transferred to step 2 later, if node A do not receive any one from The MA-Req-ACK of AP then abandons more BSS association processes；

Step 2: after the success of node A multi-connection process, being in more association status, there are time limit X, X for more association status It is provided by 802.11 agreement of WLAN of support multi-connection, under more association status, if there is upstream data needs to send, Then follow the steps 3；If receiving main AP or the scheduling frame from AP, 4 are thened follow the steps；The lower line number for being sent to node A is received from AP According to packet, 5 are thened follow the steps；If node A needs to switch main AP, 6 are thened follow the steps；

Wherein there are two types of implementations by the time limit X of more association status:

Implementation 1 is stipulated time X, and X is provided that fringe node is in multiple cell BSS (Basic Service by agreement Set after) connecting T time, fringe node after entering more association status X times, return later by automatic switchback main plot work Return step 1；

Implementation 2 is after node A switches back into main plot, to need to wait for a period of time D, D is assisted by WLAN 802.11 View regulation, cannot transmit data in time D, in order to avoid interfering to other users, if D=0, expression can be stood after switching back Channel is used, that is, degenerating is implementation 1, later return step 1；

Step 3: node A is based on enhanced distributed coordination and accesses EDCA (Enhanced Distributed Channel Access) mechanism, is performed simultaneously backoff procedure in main plot and from cell, keeps out of the way process according in EDCA mechanism, small in master It area and initializes contention window CW value respectively from cell, is then kept out of the way, it is after any one cell keeps out of the way 0, i.e., executable There are three types of implementation, three kinds of implementations are described in detail below for access and transmission process, access and transmission process:

Implementation 1: accessing in the cell that retreat count reduces to 0, in corresponding access and transmission process, all channels Mode is kept out of the way in any selection, that is, selects to keep out of the way again, or selection is once kept out of the way in cells reservation that other have not been kept out of the way Count value continues to keep out of the way；

Implementation 2: in current demand signal and interference plus noise ratio SINR (Signal to Interference plus Noise Ratio) highest cell or the average highest cell of SINR execute access and transmission process；

Implementation 3: the different community of the same channel selects the highest cell of SINR to execute access and transmission process；

Return step 2 later；

Step 4: fringe node A replys the main AP and resource request RR (resource from AP after being associated with multiple AP Request) frame, resource collect the scheduling that request RAR (resource allocation request) frame passes through the TF of each AP To execute based on orthogonal frequency-time multiple access OFDMA (Orthogonal Frequency Division Multiple Access) the uplink of technology, or triggering-resource request frame TF-RR (trigger frame- is triggered by each AP Resource request) form OFDMA random access, i.e., if AP hair is TF, execution OFDMA；If AP hair It is TF-RR, then executing OFDMA random access；

Return step 2；

Step 5: node A, with after being successfully associated AP, is sent to section if be not received by from AP in step 1, step 2 more The data packet of point A, continues to listen to channel, executes according to 802.11 agreements；If receiving the data packet for being sent to node A from AP, Ethernet packet header domain is modified, with being revised as the MAC of node A by the destination address for receiving the data packet for being sent to node A from AP Location is again seen modified data packet off by cable network from AP；

After main AP receives the data packet, it can be transmitted to node A, later return step 2；

Step 6: there are time threshold T by node A₂, T₂It is provided by 802.11 agreement of WLAN of support multi-connection, such as Fruit is more than time threshold T₂, when certain is less than main plot or handling capacity higher than main plot from the interference of cell, then starts association and cut Process is changed, the premise of starting association handoff procedure is main BSS and belongs to the same expansion service set ESS (Extended from BSS Service Set), it is associated with handoff procedure are as follows: when node A issues association request again from AP to be switched (Reassociation Request) frame replys association request again after receiving Reassociation Request frame from AP Acknowledgement frame (Reassociation Response) realizes that association switching or node A are subordinate to before carrying out more associations to node A The main AP of cell issues disassociation Disassociation, realizes association switching.

The beneficial effects of the invention are as follows due to using the associated access of more BSS and transmission method, so that being interfered in the past Biggish fringe node can carry out being associated with the AP of other cells more, increase the transmission opportunity of fringe node, solve cell side Edge user fairness poor；Due to using more BSS association access and transmission plan, edge customer access sum number is improved According to the performance of transmission, the access and transmission quality of Cell Edge User have been ensured, so that access and transmission performance are improved, solved The problem of Cell Edge User determined by neighboring community's larger interference.

Detailed description of the invention

Fig. 1 is the more associated scenes of BSS of the present invention, wherein STA indicates Cell Edge User node A, main there are three BSS The AP of cell, the AP of other two cell, i.e., AP to be selected are indicated from AP1, from AP2 where AP indicates STA.

Fig. 2 is the schematic diagram that downlink in the process modifies to ethernet packet header.

Fig. 3 is main association handoff procedure schematic diagram, wherein Reassociation Request be STA to it is to be switched from The claim frame that AP is issued, Reassociation Response is after receiving Reassociation Request frame from AP Reply frame.Disassociation is the frame that node A is issued to former main AP.

Fig. 4 is the more association process figures of committed step of embodiment 1.

Fig. 5 is the more association process figures of committed step of embodiment 2.

Fig. 6 is the more association process figures of committed step of embodiment 3.

Fig. 7 is the more association process figures of committed step of embodiment 4.

Fig. 8 is the more association process figures of committed step of embodiment 5.

Fig. 9 is the more association process figures of committed step of embodiment 6.

Figure 10 is the schematic diagram of a scenario of embodiment 7.

Figure 11 is the more association process figures of committed step of embodiment 7.

Figure 12 is the schematic diagram of a scenario of embodiment 8 and embodiment 9.

Figure 13 is the more association process figures of committed step of embodiment 8.

Figure 14 is the more association process figures of committed step of embodiment 9.

Wherein, it is channel that CRC, which is cyclic redundancy check Cyclic Redundancy Check, channel, and RTS is request Request To Send is sent, BO is to keep out of the way Back Off, and CTS is clear to send Clear To Send.

Specific embodiment

Present invention will be further explained below with reference to the attached drawings and examples.

The present invention can be realized in wireless network card by firmware, or be realized among the driver of wireless network card.

Fig. 1 is the more associated scenes of BSS of the present invention, wherein STA indicates Cell Edge User node A, main there are three BSS The AP of cell, the AP of other two cell, i.e., AP to be selected, in cell edge are indicated from AP1, from AP2 where AP indicates STA STA carries out be associated with from AP1 because experiencing itself by larger interference more.Fig. 2 be during downlink to ethernet packet header into The schematic diagram of row modification, by destination address by being changed to the MAC Address of node A from the MAC Address of AP.Fig. 3 is that main association switched Journey schematic diagram, wherein Reassociation Request is STA to the to be switched claim frame issued from AP, Reassociation Response is the reply frame received after Reassociation Request frame from AP. Disassociation is the frame that node A is issued to former main AP.

Specific implementation step is as follows:

Embodiment 1

Fig. 4 is the more association process figures of committed step of embodiment 1, it is assumed that has 3 BSS, each BSS to have one in network AP.STA in the present embodiment is under the jurisdiction of main AP, and it is channel1 from the main channel of AP1 that the main channel of main AP, which is channel1, It is channel2 from the main channel of AP2, is all from AP from AP1 and from AP2.Example illustrates that being associated with using more BSS The method of access first carries out Frame switch with main AP, obtains when so that Cell Edge User establishing be associated with the AP of other cells more After agreeing to main AP, then more association request frames are sent to establish how associated method to from AP simultaneously on the different channels.

Step 1: for when Cell Edge User (STA) is in T₁Average interference in time is greater than defined interference threshold, or Person T₁When average throughput is lower than defined throughput threshold in time, the interference threshold and throughput threshold and T₁By propping up 802.11 agreement of the WLAN regulation for holding multi-connection sends more association initialization frame MA-INIT to primary wireless access points AP, After main AP receives more association initialization frames, more association initialization are returned to STA and agree to frame MA-INIT-ACK or more associations Initialization disagrees frame MA-INIT-NAK, if STA receives MA-INIT-ACK, STA listens to multiple channels, and is subordinate to STA The multiple of other cells except the cell of category send multi-connection application frame MA-Req from AP, no matter the multiple master from AP Whether channel is identical, and MA-Req is sent in multiple channels simultaneously；After STA sends MA-Req frame, according to WLAN 802.11 agreements, the not all MA-Req frame that STA transmission can be received from AP, the slave AP that MA-Req frame is received from AP claim To be to be selected from AP, it is to be selected from AP after receiving MA-Req frame, to STA return multi-connection application agree to frame MA-Req-ACK or Multi-connection application reject frame MA-Req-NAK；If STA receives the MA-Req-ACK frame to be selected from AP, MA- is sent to STA The to be selected of Req-ACK frame forms incidence relation from AP and STA, i.e. STA is sending the to be selected from AP of MA-Req-ACK frame to STA Registration sends the to be selected of MA-Req-ACK frame to STA and provides service from AP for the STA, is transferred to step 2 later；

If STA does not receive the MA-INIT-ACK of main AP or does not receive any one MA-Req-ACK from AP, Abandon more basic service set BSS (Basic Service Set) association process；

Specific step is as follows:

Step 1.1: for when Cell Edge User (STA) is in T₁Average interference in time is greater than defined interference threshold, Or T₁When average throughput is lower than defined throughput threshold in time, the interference threshold and throughput threshold and T₁By 802.11 agreement of the WLAN regulation for supporting multi-connection sends more association initialization frame MA- to primary wireless access points AP INIT；

Step 1.2: after main AP receives more association initialization frame MA-INIT, returning to more association initialization to STA and agree to frame MA-INIT-ACK or more association initialization disagree frame MA-INIT-NAK.If returning to more association initialization agrees to frame MA- INIT-ACK then goes to step 1.3, returns to more association initialization and disagrees then return step 1.1 frame MA-INIT-NAK.

Step 1.3:STA receives MA-INIT-ACK, and STA listens to multiple channels, and respectively in channel channel1 and Channel2 is upper to send multi-connection application frame MA-Req frame to from AP1 and from AP2 simultaneously, is transferred to step 1.4 later；

Step 1.4: from AP1 and from AP2 after receiving MA-Req frame, being replied respectively in channel1 and channel2 MA-Req-ACK frame or MA-Req-NAK frame go to step 1.5 if returning to frame MA-Req-ACK frame, if returning to MA-Req- NAK frame then return step 1.1.；

Step 1.5:STA receives MA-Req-ACK frame, then with from AP1, from AP2 formed incidence relation, i.e. STA to STA sends the slave AP1 of MA-Req-ACK frame, registers from AP2, to STA send MA-Req-ACK frame it is to be selected from AP1, from AP2 Service is provided for STA, is transferred to step 2 later；If receiving MA-Req-NAK frame, return step 1.1.

Step 2: after the success of STA multi-connection process, be in more association status, more association status there are time limit X, X by Support 802.11 agreement of the WLAN regulation of multi-connection, under more association status, if there is upstream data needs to send, then Execute step 3；If receiving main AP or the scheduling frame from AP, 4 are thened follow the steps；The downlink data packet for being sent to STA is received from AP, Then follow the steps 5；If STA needs to switch main AP, 6 are thened follow the steps；

Implementation 1 is stipulated time X, and X is provided that fringe node is in multiple cell BSS (Basic Service by agreement Set after) connecting T time, fringe node STA is after entering more association status X times, automatic switchback main plot work, later Return step 1；

Implementation 2 is after STA switches back into main plot, to need to wait for a period of time D, D is by 802.11 agreement of WLAN Regulation, cannot transmit data in time D, in order to avoid interfering to other users, if D=0, expression can be immediately after switching back Using channel, that is, degenerating is implementation 1, later return step 1；

Step 3:STA is based on enhanced distributed coordination and accesses EDCA (Enhanced Distributed Channel Access) mechanism, is performed simultaneously backoff procedure in main plot and from cell, keeps out of the way process according in EDCA mechanism, small in master It area and initializes contention window CW value respectively from cell, is then kept out of the way, it is after any one cell keeps out of the way 0, i.e., executable There are three types of implementation, three kinds of implementations are described in detail below for access and transmission process, access and transmission process:

Implementation 3: the different community of the same channel selects the highest cell of SINR to execute access and transmission；

Return step 2 later；

Step 4:STA replys the main AP and resource request RR (resource from AP after being associated with multiple AP Request) frame is collected frame and is executed by the scheduling of the TF of each AP based on orthogonal frequency-time multiple access OFDMA The uplink of (Orthogonal Frequency Division Multiple Access) technology, or pass through each AP It triggers triggering-resource request frame TF-RR (trigger frame-resource request) and forms OFDMA random access, such as Fruit AP hair is TF, then executing OFDMA；If that AP hair is TF-RR, OFDMA random access is executed；

Return step 2；

Step 5:STA sends out STA's if be not received by from AP with after being successfully associated AP in step 1, step 2 more Data packet continues to listen to channel, executes according to 802.11 agreements；If receiving the data packet for being sent to STA from AP, ether is modified Packet header domain is netted, the destination address that the data packet for being sent to STA is received from AP is revised as to the MAC Address of STA, it again will modification from AP Data packet afterwards is seen off by cable network；

After main AP receives the data packet, it can be transmitted to STA, later return step 2；

There are time threshold T by step 6:STA₂, T₂It is provided by 802.11 agreement of WLAN of support multi-connection, if More than time threshold T₂, when certain is less than main plot or handling capacity higher than main plot from the interference of cell, then start association switching The premise of process, starting association handoff procedure is main BSS and belongs to the same expansion service set ESS (Extended from BSS Service Set), it is associated with handoff procedure are as follows: when STA issues association request (Reassociation again from AP to be switched Request it is real to reply Reassociation Response frame after receiving Reassociation Request frame from AP for) frame Now it is associated with the main AP sending disassociation of switching or STA to the STA cell being subordinate to before carrying out more associations (Disassociation) frame realizes association switching.

Embodiment 2

Fig. 5 is the more association process figures of committed step of embodiment 2, it is assumed that has 3 BSS, each BSS to have one in network AP.STA in the present embodiment is under the jurisdiction of main AP, and the main channel of main AP is channel1.It is channel1 from the main channel of AP1, It is channel2 from the main channel of AP2.Example illustrates that using the method for more BSS association access, so that cell side When edge user is associated with more with the AP of other cells foundation, Frame switch first is carried out with main AP, after obtaining main AP agreement, then in different letters More association request frames are sent to from AP after elder generation on road, to establish how associated method.

Step 1: for when Cell Edge User (STA) is in T₁Average interference in time is greater than defined interference threshold, or Person T₁When average throughput is lower than defined throughput threshold in time, the interference threshold and throughput threshold and T₁By propping up 802.11 agreement of the WLAN regulation for holding multi-connection sends more association initialization frame MA-INIT to primary wireless access points AP, After main AP receives more association initialization frames, more association initialization are returned to STA and agree to frame MA-INIT-ACK or more associations Initialization disagrees frame MA-INIT-NAK, if STA receives MA-INIT-ACK, STA listens to multiple channels, and is subordinate to STA The multiple of other cells except the cell of category send multi-connection application frame MA-Req from AP, no matter the multiple master from AP Whether channel is identical, and MA-Req is successively being sent in each channel respectively；After STA sends MA-Req frame, according to wireless office 802.11 agreement of domain net, it is not all can all be received from AP STA transmission MA-Req frame, received from AP MA-Req frame from AP be known as it is to be selected from AP, it is to be selected from AP after receiving MA-Req frame, to STA return multi-connection application agree to frame MA-Req-ACK or Person's multi-connection application reject frame MA-Req-NAK；If STA receives the MA-Req-ACK frame to be selected from AP, MA- is sent to STA The to be selected of Req-ACK frame forms incidence relation from AP and STA, i.e. STA is sending the to be selected from AP of MA-Req-ACK frame to STA Upper registration sends the to be selected of MA-Req-ACK frame to STA and provides service from AP for the STA, is transferred to step 2 later；

Specific step is as follows:

Step 1.1:STA is in T₁Average interference in time is greater than defined interference threshold or T₁Average throughput in time When amount is lower than defined throughput threshold, the interference threshold and throughput threshold and T₁By the wireless local area of support multi-connection 802.11 agreement of net regulation sends more association initialization frame MA-INIT to primary wireless access points AP；

Step 1.2: after main AP receives more association initialization frames, returning to more association initialization to STA and agree to frame MA- INIT-ACK or more association initialization disagree frame MA-INIT-NAK.If returning to more association initialization agrees to frame MA-INIT- ACK then goes to step 1.3, and association initialization is returned if returning and disagrees frame MA-INIT-NAK step 1.1.

After step 1.3:STA receives MA-INIT-ACK frame, multiple channels are listened to, to from AP1 on channel channel Multi-connection application frame MA-Req frame is sent, from AP1 after receiving MA-Req frame, replys MA-Req-ACK frame in channel1 Or MA-Req-NAK frame；If STA receives MA-Req-ACK frame, it is associated with AP1, is transferred to step 1.4 later；If connecing MA-Req NAK frame is received, then return step 1.1.

Step 1.4:STA be associated from AP1 after, send multi-connection application frame to from AP2 on channel channel2 MA-Req frame replys MA-Req ACK frame or MA-Req NAK frame in channel2 from AP2 after receiving MA-Req frame； If STA receives MA-Req ACK frame, it is associated with AP2 row, is transferred to step 2 later；If receiving MA-Req NAK frame, return Step 1.1.

Return step 2 later；

Return step 2；

There are time threshold T by step 6:STA₂, T₂It is provided by 802.11 agreement of WLAN of support multi-connection, if More than time threshold T₂, when certain is less than main plot or handling capacity higher than main plot from the interference of cell, then start association switching The premise of process, starting association handoff procedure is main BSS and belongs to the same expansion service set ESS (Extended from BSS Service Set), it is associated with handoff procedure are as follows: when STA issues association request Reassociation again from AP to be switched Request frame is replied Reassociation Response frame after receiving Reassociation Request frame from AP and is realized It is associated with the main AP sending disassociation Disassociation of switching or STA to the STA cell being subordinate to before carrying out more associations Frame realizes association switching.

Embodiment 3

Fig. 6 is the more association process figures of committed step of embodiment 3, it is assumed that has 3 BSS, each BSS to have one in network AP.STA in the present embodiment is under the jurisdiction of main AP, and the main channel of main AP is channel1.It is channel1 from the main channel of AP1, It is channel2 from the main channel of AP2, is all from AP from AP1 and from AP2.Example illustrates that being associated with using more BSS The method of access, when so that Cell Edge User establishing be associated with the AP of other cells more, first simultaneously to the slave AP of different channels More association request frames are sent, obtains after agreeing to from AP, reinforms main AP to establish how associated method.

Step 1: Cell Edge User STA is in T₁Average interference in time is greater than defined interference threshold or T₁Time When interior average throughput is lower than defined throughput threshold, the interference threshold and throughput threshold and T₁By support multi-connection 802.11 agreement of WLAN regulation, listen to multiple channels and to it is multiple from AP send multi-connection application frame MA-Req, nothing Whether the main channel by main AP and from AP is identical, and MA-Req is sent in multiple channels simultaneously；Receive the MA-Req of STA transmission Frame MA-Req ACK or reject frame MA-Req NAK multi-connection application are agreed in the slave AP selection of frame；It is more than or equal to if STA is received 1 AP return MA-Req ACK, then send multi-connection application agree to frame MA_Rpt (multi-associate-report) to Main AP informs more association results, that is, inform it is whether successful be associated with from AP foundation, after main AP receives MA_Rpt frame, return MA_ Rpt-ACK confirmation, is transferred to step 2 later, if not receiving any one ACK from AP, abandons more BSS association processes.Tool Steps are as follows for body:

Step 1.1:STA is calculated in T₁Average interference in time is greater than defined interference threshold or T₁It is average in time When handling capacity is lower than defined throughput threshold, the interference threshold and throughput threshold and T₁By the wireless of support multi-connection 802.11 agreement of local area network regulation, is transferred to step 1.2 later；

Step 1.2:STA listens to the two 2 channels of channel1 and channel2, and simultaneously on two channels to from AP1 and from AP2 send multi-connection application frame MA-Req, be transferred to step 1.3 later；

Step 1.3: receiving the slave AP1 of application frame MA-Req and from AP2 after receiving MA-Req frame, exist respectively Selection, which is sent, on channel1 and channel2 agrees to frame MA-Req-ACK or reject frame MA-Req-NAK multi-connection application；Such as Fruit sends MA-Req-ACK and is then transferred to step 1.4, is transferred to step 1.1 if sending MA-Req-NAK；

Step 1.4: if STA is received from AP1 and from the MA-Req-ACK frame of AP2, being closed with from AP1, from AP2 Connection retransmits MA_Rpt frame to main AP and informs more association results, is transferred to step 1.5 later；If receiving MA-Req NAK frame, Return step 1.1；

Step 1.5: after main AP receives MA-Rpt frame, MA-Rpt-ACK frame acknowledgment is sent to STA, is transferred to step 2 later, If not receiving any one ACK from AP, more BSS association processes are abandoned.；

Return step 2 later；

Return step 2；

Embodiment 4

Fig. 7 is the more association process figures of committed step of embodiment 4, it is assumed that has 3 BSS, each BSS to have one in network AP.STA in the present embodiment is under the jurisdiction of main AP, and the main channel of main AP is channel1.It is channel1 from the main channel of AP1, It is channel2 from the main channel of AP2.Example illustrates that using the method for more BSS association access, so that cell side When edge user establishes be associated with the AP of other cells more, more association request frames are successively first sent to the slave AP of different channels, are obtained Main AP is reinformed after AP agreement to establish how associated method.

Step 1: Cell Edge User (STA) is in T₁Average interference in time is greater than defined interference threshold or T₁When When interior average throughput is lower than defined throughput threshold, the interference threshold and throughput threshold and T₁By supporting connect more 802.11 agreement of the WLAN regulation connect listens to multiple channels and sends multi-connection application frame MA-Req from AP to multiple, No matter main AP and main channel from AP it is whether identical, MA-Req is successively sent in each channel respectively；Receive the MA- of STA transmission Frame MA-Req ACK or reject frame MA-Req NAK multi-connection application are agreed in the slave AP selection of Req frame；It is greater than if STA is received The MA-Req ACK that equal to 1 AP is returned then sends multi-connection application and agrees to frame MA_Rpt (multi-associate- Report more association results) are informed to main AP, that is, inform it is whether successful be associated with being established from AP, main AP receives MA_Rpt frame Afterwards, MA_Rpt-ACK confirmation is returned, is transferred to step 2 later, if not receiving any one ACK from AP, more BSS is abandoned and closes Join process.Specific step is as follows:

Step 1.1:STA is in T₁Average interference in time is greater than defined interference threshold or T₁Average throughput in time When amount is lower than defined throughput threshold, the interference threshold and throughput threshold and T₁By the wireless local area of support multi-connection 802.11 agreement of net regulation.

Step 1.2: listening to the two 2 channels of channel1 and channel2, and to from AP1 on channel1 channel Send multi-connection application frame MA-Req；

Step 1.3: from AP1 after receiving MA-Req frame, according to channel1 reply MA-Req-ACK frame or MA-Req-NAK frame；

Step 1.4: if STA receives the MA-Req-ACK frame from AP1, being associated with from AP1, be transferred to step later 1.5；If receiving MA-Req-NAK frame, return step 1.1.

Step 1.5:STA be associated from AP1 after, send multi-connection application frame to from AP2 on channel2 channel MA-Req replys MA-Req-ACK frame or MA-Req-NAK frame in channel2 from AP2 after receiving MA-Req frame, it After be transferred to step 1.6；

Step 1.6:STA receives the MA-Req-ACK frame from AP2, is associated with from AP2, is transferred to step later 1.7；If receiving MA-Req-NAK frame, return step 1.1.

Step 1.7: after main AP receives MA-Rpt frame, sending MA-Rpt-ACK frame acknowledgment to main AP；It is transferred to step later 2, otherwise abandon more BSS association processes；

Return step 2 later；

Return step 2；

Embodiment 5

Fig. 8 is the more association process figures of committed step of embodiment 5, it is assumed that has 3 BSS, each BSS to have one in network AP.STA in the present embodiment is under the jurisdiction of main AP.The AP of other two BSS is respectively from AP1 and from AP2.Cell where main AP For main plot, cell where from AP1 is from cell 1, and cell where from AP2 is from cell 2.Example illustrates that using The method of more BSS association accesses, so that Cell Edge User is moved back with after being associated with AP foundation in main plot and from cell more simultaneously It keeps away, retains upper primary biography in other channels that do not kept out of the way when being accessed in the cell for keeping out of the way 0, and kept out of the way next time Transmission of data, the method that the remaining backoff value of other channels continues to keep out of the way when a channel keeps out of the way 0.

Step 1: Cell Edge User STA arbitrarily selects the following two kinds implementation when carrying out more associations:

Implementation 1 is when Cell Edge User STA is in T₁Average interference in time is greater than defined interference threshold, or Person T₁When average throughput is lower than defined throughput threshold in time, the interference threshold and throughput threshold and T₁By propping up 802.11 agreement of the WLAN regulation for holding multi-connection sends more associations just to primary wireless access points AP (access point) After beginningization frame MA-INIT (Multi-associate initialization), main AP receive more association initialization frames, to STA returns to more association initialization and agrees to frame MA-INIT-ACK (Multi-associate initialization Acknowledgement) or more association initialization disagree frame MA-INIT-NAK (Multi-associate Initialization not acknowledgement), if STA receives MA-INIT-ACK, STA listens to multiple channels, and The multiple of other cells except to STA cell subjected send multi-connection application frame MA-Req (multi- from AP Access-request), no matter whether the multiple main channel from AP identical, MA-Req multiple channels simultaneously send or Person successively sends on each channel respectively；After STA sends MA-Req frame, according to 802.11 agreement of WLAN, it is not All MA-Req frames that STA transmission can be all received from AP, received from AP MA-Req frame slave AP be known as it is to be selected from AP, it is to be selected from AP returns to multi-connection application to STA and agrees to frame MA-Req-ACK (multi-access-request after receiving MA-Req frame ) or multi-connection application reject frame MA-Req-NAK (multi-access-request not acknowledgement acknowledgement)；If STA receives the MA-Req-ACK frame to be selected from AP, to STA send MA-Req-ACK frame to Choosing forms incidence relation from AP and STA, i.e. STA is registered from AP to STA transmission the to be selected of MA-Req-ACK frame, sent out to STA It send the to be selected of MA-Req-ACK frame to provide service from AP for the STA, is transferred to step 2 later；

Implementation 2 is Cell Edge User STA in T₁Average interference in time is greater than defined interference threshold, or T₁When average throughput is lower than defined throughput threshold in time, the interference threshold and throughput threshold and T₁By supporting 802.11 agreement of WLAN of multi-connection provides, listens to multiple channels and sends multi-connection application frame MA- from AP to multiple Req, no matter main AP and main channel from AP it is whether identical, MA-Req sends in multiple channels simultaneously or successively respectively each It is sent on a channel；Frame MA-Req-ACK or reject frame MA-Req- is agreed in the slave AP selection for receiving the MA-Req frame of STA transmission NAK multi-connection application；If STA receives the MA-Req-ACK returned more than or equal to 1 AP, sends multi-connection application and agree to frame Whether MA_Rpt (multi-associate-report) informs more association results to main AP, that is, inform to succeed and establish pass with from AP Connection after main AP receives MA_Rpt frame, returns to MA_Rpt ACK frame (multi-associate-report Acknowledgement) confirm, be transferred to step 2 later, if STA does not receive any one MA-Req-ACK from AP, put Abandon more BSS association processes；

Step 3:STA is based on enhanced distributed coordination and accesses EDCA mechanism, moves back in main plot and being performed simultaneously from cell Journey is circumvented, keeps out of the way process according in EDCA mechanism, contention window CW value is initialized respectively in main plot and from cell, then carries out Keep out of the way, after any one cell keeps out of the way 0, i.e., executable access and transmission process connect in the cell that retreat count reduces to 0 Enter, in corresponding access and transmission process, all channels arbitrarily select to keep out of the way mode, that is, select to keep out of the way again, or selection exists Other cells that do not kept out of the way retain last retreat count and continue to keep out of the way；

Step 3.1:STA is based on EDCA mechanism after the completion of with from AP1 and from more associations of AP2, in main plot and from small Area is performed simultaneously stochastic backoff process, is transferred to step 3.1.

Step 3.2:STA is taking the lead in completing to keep out of the way from cell 1, that is, keeps out of the way 0, then accessed from cell 1, be transferred to step Rapid 3.3；

Step 3.3:STA is being accessed and is being transmitted from cell 1, and when next time is accessed, all channels arbitrarily select the side of keeping out of the way Formula selects to keep out of the way again, or selection retains upper primary retreat count in other cells that do not kept out of the way and continues to keep out of the way. Return step 2；

Return step 2；

Embodiment 6

Fig. 9 is the more association process figures of committed step of embodiment 6, it is assumed that has 3 BSS, each BSS to have one in network AP.STA in the present embodiment is under the jurisdiction of main AP.The AP of other two BSS is respectively from AP1 and from AP2, from AP1 and from AP2 It is from AP.Cell where main AP is main plot, and cell where from AP1 is from cell 1, and cell where from AP2 is from cell 2. Example illustrates that using more BSS association access method so that Cell Edge User with from AP establish more be associated with after, Keep out of the way simultaneously in main plot and from cell, a cell takes the lead in completing to keep out of the way, but is connect in the highest cell of another SINR The method entered.

Step 3:STA is based on EDCA mechanism, stochastic backoff process is performed simultaneously in main plot and from cell, according to EDCA Keep out of the way process in mechanism, initializes contention window CW value respectively in main plot and from cell, then kept out of the way, any one is small After area keeps out of the way 0, accessed in the highest cell of another average sinr value.

Step 3.1:STA is based on EDCA mechanism after the completion of with from AP1 and from more associations of AP2, in main plot and from small Area is performed simultaneously stochastic backoff process.

Step 3.2:STA is taking the lead in completing to keep out of the way from cell 2, that is, keeps out of the way 0；

Step 3.3:STA is accessed and is transmitted at the highest cell of average sinr value (from cell 1), later return step 2；

Return step 2；

Embodiment 7

Figure 10 is the schematic diagram of a scenario of embodiment 7, and Figure 11 is the more association process figures of committed step of embodiment 7, it is assumed that net There are 4 BSS, the STA in the present embodiment to be under the jurisdiction of main AP in network.Cell where main AP is main plot, cell where from AP1 For from cell 1, cell where from AP2 is from cell 2, and cell where from AP3 is to share one from cell 2 from cell 3 from cell 3 A channel.Example illustrates that using the method for more BSS association access, so that Cell Edge User enters more association shapes After state, in the time limit T as defined in agreement when uplink transmission data, the method for the slave AP transmission data of first backward different channels.

Step 2.1: in time T, STA first with from AP1 carry out data access and transmission, then with sharing same channel Slave AP2 and carry out data transmission from AP3, after time T, switch back into main plot；

Step 2.2: after switching back into main plot, wait for a period of time D, D by 802.11 agreement of WLAN provide, when Between cannot transmit data in D, in order to avoid interfering to other users, after time D, if D=0, expression can be stood after switching back Channel is used, that is, degenerating is implementation 1, later return step 1；

Step 3:STA is based on enhanced distributed coordination and accesses EDCA (Enhanced Distributed Channel Access) mechanism, is performed simultaneously backoff procedure in main plot and from cell, keeps out of the way process according in EDCA mechanism, small in master It area and initializes contention window CW value respectively from cell, is then kept out of the way, after any one cell keeps out of the way 0, believed currently Number and the highest cell of interference plus noise ratio SINR or the highest cell of average SINR execute access and transmission process.

Step 3.1:STA with from AP1, from AP2 and from more associations of AP3 after the completion of, be based on EDCA mechanism, in main plot Stochastic backoff process is performed simultaneously with from cell.

After step 3.2:STA completion is kept out of the way, Xiang Cong AP1 access and uplink transmission data；

Step 3.3: share the same channel from cell 2 and from cell 3, STA with transmit data from AP1 after the completion of, again Keep out of the way, after the completion of keeping out of the way, is held in current demand signal and the highest cell of interference plus noise ratio SINR or the average highest cell of SINR Row access and transmission process；Return step 2.

Return step 2；

Embodiment 8

Figure 12 is the schematic diagram of a scenario of embodiment 8, and Figure 13 is the more association process figures of committed step of embodiment 8.Assuming that net There are 3 BSS, each BSS to have an AP in network.STA in the present embodiment is under the jurisdiction of main AP.The AP of other two BSS distinguishes To be not operate at same channel from AP1 and from AP2 from AP1 and from AP2.Example illustrates that being connect using more BSS association The method entered, so that after Cell Edge User enters more association status, in the time limit T as defined in agreement when uplink transmission data, Simultaneously to the method for the slave AP of different channels transmission data.

Step 2.2: after switching back into main plot, wait for a period of time D, and D is provided by 802.11 agreement of WLAN, in D Interior to transmit data, in order to avoid interfering to other users, after time D, if D=0, expression can make immediately after switching back With channel, that is, degenerating is implementation 1, later return step 1；

Step 3.1:STA uses above-mentioned implementation method, is accessed after the completion of keeping out of the way；

Step 3.2:STA is accessed from cell 2 simultaneously and from cell 1 and is transmitted data；Return step 2 later.

Return step 2；

Embodiment 9

Figure 12 is the schematic diagram of a scenario of embodiment 9, and Figure 14 is the more association process figures of committed step of embodiment 9.Assuming that net There are 3 BSS, each BSS to have an AP in network.STA in the present embodiment is under the jurisdiction of main AP.The AP of other two BSS distinguishes For from AP1 and from AP2.Example illustrates that using the method for more BSS association access, so that Cell Edge User enters After more association status, in the time limit T as defined in agreement after uplink transmission data, after switching back into main plot, discovery can not transmit number According to elder generation starts the method for being accessed and being transmitted data with main AP after freezing a period of time D without data transmission again.

Step 2.1: in time T, STA carries out uplink with from AP1 and from AP2 simultaneously, after time T, switches back into Main plot；

Step 2.2: after switching back into main plot, STA discovery can not transmit data, when first freezing one section without data transmission Between D, in order to avoid interfering other users, then start to be accessed and transmitted data with main AP.Return step 1 later.

Return step 2；

Step 5:STA sends out STA's if be not received by from AP with after being successfully associated AP in step 1, step 2 more Data packet continues to listen to channel, executes according to 802.11 agreements；If receiving the data packet for being sent to STA from AP, ether is modified Packet header domain is netted, the destination address that the data packet for being sent to node A is received from AP is revised as to the MAC Address of STA, will be repaired again from AP Data packet after changing is seen off by cable network；

Claims

1. a kind of method based on more BSS associated access and transmission, it is characterised in that include the following steps:

Implementation 1 is when Cell Edge User node A is in T₁Average interference in time is greater than defined interference threshold, or T₁When average throughput is lower than defined throughput threshold in time, the interference threshold, throughput threshold and T₁It is more by supporting 802.11 agreement of WLAN of connection provides, sends more association initialization to primary wireless access points AP (access point) After frame MA-INIT (Multi-associate initialization), main AP receive more association initialization frames, Xiang Jiedian A It returns to more association initialization and agrees to frame MA-INIT-ACK (Multi-associate initialization Acknowledgement) or more association initialization disagree frame MA-INIT-NAK (Multi-associate Initialization not acknowledgement), if node A receives MA-INIT-ACK, node A listens to multiple letters Road, and multi-connection application frame MA-Req (multi- is sent from AP to the multiple of other cells except node A cell subjected Access-request), no matter whether the multiple main channel from AP identical, MA-Req multiple channels simultaneously send or Successively send on each channel respectively；After node A sends MA-Req frame, according to 802.11 agreement of WLAN, it is not It is all can all be received from AP node A transmission MA-Req frames, received from AP MA-Req frame slave AP be known as it is to be selected from AP, it is to be selected From AP after receiving MA-Req frame, Xiang Jiedian A returns to multi-connection application and agrees to frame MA-Req-ACK (multi-access- Request acknowledgement) or multi-connection application reject frame MA-Req-NAK (multi-access-request not acknowledgement)；If node A receives the MA-Req-ACK frame to be selected from AP, MA-Req- is sent to node A The to be selected of ACK frame forms incidence relation from AP and node A, i.e. node A is sending the to be selected from AP of MA-Req-ACK frame to node A Upper registration, Xiang Jiedian A send the to be selected of MA-Req-ACK frame and provide service from AP for node A, are transferred to step 2 later；

If node A does not receive the ACK of main AP or do not receive any one MA-Req-ACK from AP, abandon mostly basic Services set BSS (Basic Service Set) is associated with process；

Implementation 2 is Cell Edge User node A in T₁Average interference in time is greater than defined interference threshold or T₁ When average throughput is lower than defined throughput threshold in time, the interference threshold and throughput threshold and T₁It is more by supporting 802.11 agreement of WLAN of connection provides, listens to multiple channels and sends multi-connection application frame MA- from AP to multiple Req, no matter main AP and main channel from AP it is whether identical, MA-Req sends in multiple channels simultaneously or successively respectively each Channel is sent；Frame MA-Req-ACK or reject frame MA-Req-NAK is agreed in the slave AP selection for receiving the MA-Req frame of node A transmission Multi-connection application；If node A receives the MA-Req-ACK returned more than or equal to 1 AP, sends multi-connection application and agree to frame Whether MA_Rpt (multi-associate-report) informs more association results to main AP, that is, inform to succeed and establish pass with from AP Connection after main AP receives MA_Rpt frame, returns to multi-connection request and agrees to acknowledgement frame MA_Rpt ACK frame (multi-associate- Report acknowledgement) confirmation, it is transferred to step 2 later, if node A does not receive any one MA- from AP Req-ACK then abandons more BSS association processes；

Step 2: after the success of node A multi-connection process, being in more association status, more association status are there are time limit X, and X is by propping up 802.11 agreement of the WLAN regulation for holding multi-connection, under more association status, if there is upstream data needs to send, then holds Row step 3；If receiving main AP or the scheduling frame from AP, 4 are thened follow the steps；The downlink data packet for being sent to node A is received from AP, Then follow the steps 5；If node A needs to switch main AP, 6 are thened follow the steps；

Implementation 1 is stipulated time X, and X is provided by agreement, and fringe node connects at multiple cell BSS (Basic Service Set) After connecing T time, automatic switchback main plot works, later return step 1；

Implementation 2 is to need to wait for a period of time D after node A switches back into main plot, and D is advised by 802.11 agreement of WLAN It is fixed, data cannot be transmitted in time D, in order to avoid interfering to other users, if D=0, expression can make immediately after switching back With channel, that is, degenerating is implementation 1, later return step 1；

Step 3: node A is based on enhanced distributed coordination and accesses EDCA (Enhanced Distributed ChannelAccess) mechanism, is performed simultaneously backoff procedure in main plot and from cell, keeps out of the way process according in EDCA mechanism, Contention window CW value is initialized respectively in main plot and from cell, is then kept out of the way, after any one cell keeps out of the way 0, i.e., There are three types of implementation, three kinds of implementations are described in detail below for executable access and transmission process, access and transmission process:

Implementation 1: 0 cell access is reduced in retreat count, in transmission process, all channels are any for corresponding access Mode is kept out of the way in selection, that is, selects to keep out of the way again, or selection once keeps out of the way counting in cells reservation that other have not been kept out of the way Value continues to keep out of the way；

Return step 2 later；

Return step 2；

Step 5: node A, with after being successfully associated AP, is sent to node A if be not received by from AP in step 1, step 2 more Data packet, continue to listen to channel, according to 802.11 agreements execute；If receiving the data packet for being sent to node A from AP, modification The destination address that the data packet for being sent to node A is received from AP is revised as the MAC Address of node A by ethernet packet header domain, from AP Modified data packet is seen off by cable network again；

Step 6: there are time threshold T by node A₂, T₂It is provided by 802.11 agreement of WLAN of support multi-connection, if super Cross time threshold T₂, when certain is less than main plot or handling capacity higher than main plot from the interference of cell, then starts association and switched The premise of journey, starting association handoff procedure is main BSS and belongs to the same expansion service set ESS (Extended from BSS Service Set), it is associated with handoff procedure are as follows: when node A issues association request again from AP to be switched (Reassociation Request) frame replys association request again after receiving Reassociation Request frame from AP Acknowledgement frame (Reassociation Response) realizes that association switching or node A are subordinate to before carrying out more associations to node A The main AP of cell issues disassociation Disassociation, realizes association switching.