CN104661320B - Channel access control method and device - Google Patents

Abstract

The embodiment of the present application discloses a kind of channel access control method and device, this method comprises: receiving the data packet that sender sends；Judge described sender whether according to cycle T access channel according to the data packet；When described sender accesses channel according to cycle T, rollback is executed at the t1+nT moment, wherein n is positive integer, and the initial value of n is the time of reception that 1, t1 is the data packet.This method, for the terminal being located in sender's coverage area, when sender is when sending data packet at the t1 moment, terminal can receive the data packet, and can use the data packet received determine sender whether according to cycle T access channel, when determine sender according to cycle T access channel when, execute rollback at the t1+nT moment, and then it can guarantee that sender can access channel, execution cycle business data transmission with the period.

Description

Channel access control method and device

Technical field

This application involves fields of communication technology, more particularly to a kind of channel access control method and device.

Background technique

MAC(Media Access Control, media access control layer) provide numerous functions, wherein addressing function and Channel access control function makes multiple STA(Station on consolidated network, website) intercommunication be possibly realized. 802.11n MAC supports the shared access to wireless medium, this is to be referred to as CSMA/CA(Carrier Sense by one kind Multiple Access with Collision Avoidance, band avoid collision the carrier sense multiple access of function) Technology is realized.

CSMA/CA mechanism used in 802.11n MAC is referred to as DCF(Distributed Coordination Function, distributed coordination function).When STA intends to send data packet, it first to media carry out one it is fixed when Long listens to, and to assess whether a channel can be used, this is fixed duration and is referred to as DIFS(DCF Inter-frame Space, Distributed coordination function frame pitch).If media state is the free time, which thinks that it can possess media, and starts one A Frame switch.If media state be it is busy, which needs that medium is waited to become idle state, after prolong DIFS duration, go forward side by side One step waits a random backoff period.If media prolong after DIFS and backoff period during keep idle state, The STA website thinks that it can possess media, and starts a Frame switch.

It can be seen that DCF provides a kind of channel access function distributed, competition-based, each STA need not be concentrated The coordinator or moderator of formula, but channel access is obtained by competition, so that the highly effective rate of this mechanism, and in work Bandwidth is liberally assigned between jump website.

However when there is website to there is business to need periodically access, such as: voice service is stood using existing DCF technology There is still a need for competitions can just access channel access in subsequent each cycle time point for point, but since the backoff period of waiting is random , so not can guarantee website can compete success in each cycle time point, and then it is unable to satisfy the period for needing business Property access channel demands.

Summary of the invention

Provided herein a kind of channel access control method and device, are unable to satisfy business to solve the prior art The problem of periodically accessing channel demands.

In order to solve the above-mentioned technical problem, this application discloses following technical solutions:

In a first aspect, this application provides a kind of channel access control methods, comprising: receive the data that sender sends Packet；Judge described sender whether according to cycle T access channel according to the data packet；When described sender connects according to cycle T When entering channel, rollback is executed at the t1+nT moment, wherein n is positive integer, and the initial value of n is the reception that 1, t1 is the data packet Moment.

With reference to first aspect, in a first possible implementation of that first aspect, according to data packet judgement Whether sender is according to cycle T access channel, comprising: detects all with the presence or absence of described sender is used to indicate in the data packet The mark of phase access channel；When there are the mark, determine that the described sender period accesses channel；It extracts in the data packet The sender of carrying accesses the cycle T of channel.

With reference to first aspect, in a second possible implementation of that first aspect, according to data packet judgement Whether sender is according to cycle T access channel, comprising: the packet for detecting the data packet is long；Judge that the packet is long whether to be less than in advance If wrapping long threshold value；When the packet is long is less than the long threshold value of default packet, determine that the described sender period accesses channel；According to setting in advance The corresponding relationship for the Bao Changyu access period set obtains the cycle T of described sender access channel.

With reference to first aspect, in first aspect in the third possible implementation, according to data packet judgement Whether sender is according to cycle T access channel, comprising: detects the value that reserved bit is preset in the data packet, the default reservation Position is used to indicate whether data packet is IP phone VoIP data packet；When the value of preset reserved bit indicates the data When packet is VoIP data packet, determine that the described sender period accesses channel；According to pre-set VoIP data packet and access week The corresponding relationship of phase obtains the cycle T of described sender access channel.

With reference to first aspect, the first possible implementation of first aspect, second of first aspect possible realization side Formula or first aspect the third possible implementation, in the 4th kind of possible implementation of first aspect, at the t1+nT moment Execute rollback, comprising: set T- (t2-t1) for the duration of Backoff timer；As n=1, start timing at the t2 moment, and work as When timing length is equal to T- (t2-t1), Backoff window is set according to preset duration, the Backoff window will be to be sent for controlling Prolong to after the Backoff window after the sending instant of data, t2 is the finish time of the data packet；When n is greater than 1, detection Whether data packet is received at the t1+nT moment；When t1+nT reception is to data packet, each data packet at the end of Start timing after quarter, and when timing length is equal to T- (t2-t1), Backoff window is set according to identical preset duration；When When not receiving data packet at the t1+nT moment, the duration of the Backoff timer is reset, terminates to retract.

With reference to first aspect in the 4th kind of possible implementation, in the 5th kind of possible implementation of first aspect, The method also includes: it detects the preset sending instant of data to be sent and occupies duration region, the occupancy duration includes: number According to duration is sent, or, data send duration and receive the duration of the ACK message fed back to the data to be sent；According to The sending instant and occupancy duration region, judge whether the occupancy duration region of the data to be sent covers next rollback Window；When the next Backoff window of the occupancy duration region overlay of the data to be sent, the data to be sent are carried out Segmentation obtains multiple segment datas, and determines the sending instant of each segment data, and the sending instant of each segment data makes The occupancy duration region of the segment data does not cover next Backoff window；According to distributed coordination function DCF mode or increasing Strong distributed channel access EDCA mode accesses channel, to send the segment data；When the occupancy of the data to be sent When long region does not cover next Backoff window, according to distributed coordination function DCF mode or enhancing distributed channel access EDCA mode accesses channel, to send the data to be sent.

Second aspect, this application provides also a kind of channel access control methods, comprising: confirmation character ACK message is received, The ACK message is the report that the data packet that base station, site STA or access point AP send sender in coverage area is fed back Text；Judge described sender whether according to cycle T access channel according to the ACK message；When described sender connects according to cycle T When entering channel, rollback is executed at the t3+T-Duration+ short frame interval SIFS moment, wherein t3 is the end of the ACK message Moment, Duration are the value in the domain Duration in the ACK message.

In conjunction with second aspect, in second aspect in the first possible implementation, according to ACK message judgement Whether sender is according to cycle T access channel, comprising: detecting, which whether there is in the ACK message, is used to indicate described sender The mark of period access channel；When detecting the mark, determine that the described sender period accesses channel；Extract the ACK The cycle T of the described sender access channel carried in message.

In conjunction with second aspect, in second of second aspect possible implementation, according to ACK message judgement Whether sender is according to cycle T access channel, comprising: detects the value in the domain Duration in the ACK message；Described in judgement Whether the value in the domain Duration is less than targets threshold；When the value in the domain Duration is less than targets threshold, the hair is determined The side's of sending period accesses channel；According to the corresponding relationship of the value in the default domain Duration and access period, obtains described sender and connect Enter the cycle T of channel.

In conjunction with second aspect, in second aspect in the third possible implementation, according to ACK message judgement Whether sender is according to cycle T access channel, comprising: detects the value that indicating bit is preset in the ACK message, the default instruction Whether the data packet that position is used to indicate described sender transmission is IP phone VoIP data packet；When the default instruction When the data packet that the value instruction described sender of position is sent is VoIP data packet, determine that the described sender period accesses channel；Root According to the value of pre-stored default indicating bit and the corresponding relationship of access period, the cycle T of described sender access channel is obtained.

In conjunction with second aspect, second aspect the first possible implementation, second of second aspect possible realization side Formula or second aspect the third possible implementation, in the 4th kind of possible implementation of second aspect, in t3+T- The Duration+SIFS moment executes rollback, comprising: T-Duration+SIFS is set by the duration of Backoff timer, in t3 It carves and starts timing；When timing length is equal to T-Duration+SIFS, Backoff window, the rollback are set according to preset duration Window is for controlling and prolonging after the sending instant of data to be sent to after the Backoff window.

The third aspect, present invention also provides a kind of channel access control devices, comprising: data receipt unit, for connecing The data packet that the side of transmitting and receiving is sent；First channel access judging unit, for judging that described sender is according to the data packet It is no to access channel according to cycle T；First rollback control unit is used for when described sender accesses channel according to cycle T, in t1 + nT the moment executes rollback, wherein n is positive integer, and the initial value of n is the time of reception that 1, t1 is the data packet.

In conjunction with the third aspect, in the third aspect in the first possible implementation, the first channel access judgement is single Member includes:

First identifier detection unit connects for detecting in the data packet with the presence or absence of being used to indicate the described sender period Enter the mark of channel；First channel access determination unit, for when there are the mark, determining that the described sender period is accessed Channel；Period 1 acquiring unit accesses the cycle T of channel for extracting the sender carried in the data packet.

In conjunction with the third aspect, in second of the third aspect possible implementation, the first channel access judgement is single Member includes:

Long detection unit is wrapped, the packet for detecting the data packet is long；Long judging unit is wrapped, for judging that the packet length is It is no to be less than the default long threshold value of packet；Second channel access determination unit, for determining when the long long threshold value less than default packet of the packet Sender's period accesses channel；Second round acquiring unit, for being closed according to the corresponding of pre-set Bao Changyu access period System obtains the cycle T of described sender access channel.

In conjunction with the third aspect, in the third aspect in the third possible implementation, the first channel access judgement is single Member includes:

Reserved bit detection unit, for detecting the value for presetting reserved bit in the data packet, the default reserved bit is used for Whether designation date packet is IP phone VoIP data packet；Third channel access determination unit presets guarantor for working as When the value of position being stayed to indicate that the data packet is VoIP data packet, determine that the described sender period accesses channel；Period 3 obtains Unit obtains described sender and accesses channel for the corresponding relationship according to pre-set VoIP data packet and access period Cycle T.

In conjunction with the third aspect, the third aspect the first possible implementation, second of the third aspect possible realization side Formula or the third aspect the third possible implementation, in the 4th kind of possible implementation of the third aspect, described first time Moving back control unit includes: the first rollback timing unit, for setting T- (t2-t1) for the duration of Backoff timer as n=1, And starting timing at the t2 moment, t2 is the finish time of the data packet；First Backoff window setting unit, it is long for working as timing When degree is equal to T- (t2-t1), Backoff window is set according to preset duration, the Backoff window is for controlling data to be sent Prolong to after the Backoff window after sending instant；Data detecting unit, for detecting in t1+nT moment institute when n is greater than 1 State whether data receipt unit receives data packet；Rollback finishing control unit, for when the data receiver described in the t1+nT moment When unit does not receive data packet, the duration of the Backoff timer is reset, terminates to retract；The first rollback timing unit It is also used to when t1+nT reception is to data packet, starts timing after the finish time of each data packet, described first time When moving back window setting unit and being also used to the timing length after each data packet finish time and be equal to T- (t2-t1), according to identical Backoff window is arranged in preset duration.

In conjunction with the 4th kind of possible implementation of the third aspect, in the 5th kind of possible implementation of the third aspect, institute State device further include: data detecting unit to be sent, for detecting the preset sending instant of data to be sent and occupying duration area Domain, the occupancy duration includes: that data send duration, or, data send duration and receive anti-to the data progress to be sent The duration of the ACK message of feedback；Region overlay judging unit, for judging institute according to the sending instant and occupancy duration region Whether the occupancy duration region for stating data to be sent covers next Backoff window；Data segmentation unit, for working as region overlay The judging result of judging unit is to be segmented the data to be sent to obtain multiple segment datas, and determine each when being The sending instant of segment data, the sending instant of each segment data cover the occupancy duration region of the segment data not Next Backoff window；Channel access unit, for according to distributed coordination function DCF mode or enhancing distributed channel access EDCA mode accesses channel, to send the segment data or the data to be sent.

Fourth aspect, present invention also provides a kind of channel access control devices, comprising: message receiving unit, for connecing Confirmation character ACK message is received, the ACK message is that base station, site STA or access point AP send sender in coverage area The message that data packet is fed back；Second channel accesses judging unit, for judging that described sender is according to the ACK message It is no to access channel according to cycle T；Second rollback control unit is used for when described sender accesses channel according to cycle T, in t3 + T-Duration+ short frame interval SIFS the moment executes rollback, wherein t3 is the finish time of the ACK message, Duration For the value in the domain Duration in the ACK message.

In conjunction with fourth aspect, in fourth aspect in the first possible implementation, the second channel access judgement is single Member, comprising: second identifier detection unit is used to indicate the described sender period for detecting to whether there is in the ACK message Access the mark of channel；4th channel access determination unit, for when detecting the mark, determining the described sender period Access channel；Period 4 acquiring unit, for extracting the period of the described sender carried in the ACK message access channel T。

In conjunction with fourth aspect, in second of fourth aspect possible implementation, the second channel access judgement is single Member, comprising: packet check unit, for detecting the value in the domain Duration in the ACK message；Threshold decision unit, for sentencing Whether the value in the domain Duration of breaking is less than targets threshold；5th channel access determination unit, for working as the Duration When the value in domain is less than targets threshold, determine that the described sender period accesses channel；Period 5 acquiring unit, for according to default The value in the domain Duration and the corresponding relationship of access period obtain the cycle T of described sender access channel.

In conjunction with fourth aspect, in fourth aspect in the third possible implementation, the second channel access judgement is single Member, comprising: indicating bit detection unit, for detecting the value for presetting indicating bit in the ACK message, the default indicating bit is used for Whether the data packet for indicating that described sender is sent is VoIP data packet；6th channel access determination unit, for when described pre- If the data packet that the value instruction described sender of indicating bit is sent is IP phone VoIP data packet, the hair is determined The side's of sending period accesses channel；Period 6 acquiring unit, value and access period for default indicating bit according to the pre-stored data Corresponding relationship, obtain described sender access channel cycle T.

In conjunction with fourth aspect, fourth aspect the first possible implementation, second of fourth aspect possible realization side Formula or fourth aspect the third possible implementation, in the 4th kind of possible implementation of fourth aspect, described second time Moving back control unit includes: the second rollback timing unit, for setting T-Duration+SIFS for the duration of Backoff timer, Start timing at the t3 moment；Second Backoff window setting unit, for pressing when timing length is equal to T-Duration+SIFS Backoff window is set according to preset duration, the Backoff window is for controlling and prolonging after the sending instant of data to be sent to described time After moving back window.

5th aspect, present invention also provides a kind of terminals, control dress including the channel access that the third aspect as above provides At least one of the channel access control device provided with fourth aspect as above is provided.

By above technical scheme as it can be seen that the channel access control method provided by the present application, covers for being located at sender Terminal in range, when sender is when sending data packet at the t1 moment, terminal can receive the data packet, and can use The data packet received determine sender whether according to cycle T access channel, when determine sender according to cycle T access channel When, rollback is executed at the t1+nT moment, and then can guarantee that sender can access channel with the period, execution cycle business datum passes It is defeated.

Detailed description of the invention

In order to illustrate the technical solutions in the embodiments of the present application or in the prior art more clearly, to embodiment or will show below There is attached drawing needed in technical description to be briefly described, it should be apparent that, for those of ordinary skill in the art Speech, without any creative labor, is also possible to obtain other drawings based on these drawings.

Fig. 1 is a kind of topological relation figure provided by the embodiments of the present application；

Fig. 2 is a kind of flow diagram of channel access control method provided by the embodiments of the present application；

Fig. 3 is a kind of channel access control sequential figure provided by the embodiments of the present application；

Fig. 4 is a kind of flow diagram of step 102 provided by the embodiments of the present application；

Fig. 5 is another flow diagram of step 102 provided by the embodiments of the present application；

Fig. 6 is another flow diagram of step 102 provided by the embodiments of the present application；

Fig. 7 is a kind of flow diagram of step 103 provided by the embodiments of the present application；

Fig. 8 is the flow diagram of another channel access control method provided by the embodiments of the present application；

Fig. 9 is the flow diagram of another channel access control method provided by the embodiments of the present application；

Figure 10 is another channel access control sequential figure provided by the embodiments of the present application；

Figure 11 is a kind of flow diagram of step S602 provided by the embodiments of the present application；

Figure 12 is another flow diagram of step S602 provided by the embodiments of the present application；

Figure 13 is another flow diagram of step S602 provided by the embodiments of the present application；

Figure 14 is a kind of flow diagram of step S603 provided by the embodiments of the present application；

Figure 15 is a kind of flow diagram of data packet generation method provided by the embodiments of the present application；

Figure 16 is a kind of flow diagram of ACK message forming method provided by the embodiments of the present application；

Figure 17 is a kind of structural schematic diagram of channel access control device provided by the embodiments of the present application；

Figure 18 is the structural schematic diagram of the first rollback control unit provided by the embodiments of the present application；

Figure 19 is the structural schematic diagram of another channel access control device provided by the embodiments of the present application；

Figure 20 is the structural schematic diagram of another channel access control device provided by the embodiments of the present application；

Figure 21 is a kind of structural schematic diagram of terminal provided by the embodiments of the present application.

Specific embodiment

In order to make those skilled in the art more fully understand the technical solution in the embodiment of the present application, and keep the application real The above objects, features, and advantages for applying example can be more obvious and easy to understand, with reference to the accompanying drawing to technical side in the embodiment of the present application Case is described in further detail.

Channel access control method provided by the embodiments of the present application can be used for any device for receiving wireless data, example Such as: terminal, base station, STA(Station, website), AP(Access Point, access point) and other communication equipments, the channel Connection control method, data packet sender sent by the data packet or other communication equipments that receive sender's transmission into The ACK message of row feedback selectively can execute rollback at the time of sender's subsequent periodic accesses channel, avoid the occurrence of The problem of with the periodic traffic data collision of sender, guarantees that sender can periodically access in sending cycle business datum Channel.

In the embodiment of the present application, the channel access control method provided by the embodiments of the present application is carried out by taking website as an example Illustrate, Fig. 1 is a kind of topological relation figure provided by the embodiments of the present application.As shown in Figure 1, STA1 is sending cycle business number in figure According to website, the access point that is communicated when AP1 is 1 sending cycle business datum of site STA, STA2 is in AP1 coverage area Website, site STA 2 can receive the ACK message that AP1 is issued, and STA3 is the website in 1 coverage area of site STA, website STA3 can receive the data packet of website STA1 transmission, and STA4 is a website in access point AP1 coverage area.In this Shen Site STA 1, STA2, STA3 and STA4 it please all refer to a kind of website in embodiment, rather than a specific website.

When site STA 1 is in sending cycle business datum, site STA 2 in 1 coverage area of site STA and it is located at Site STA 3 in AP1 coverage area may carry out channel competition with site STA 1, and then influence the sending cycle of site STA 1 The success rate of channel is accessed when business datum.

Below by taking site STA 3 as an example, channel access control method provided by the embodiments of the present application is illustrated, such as Fig. 2 It is shown, the channel access control method the following steps are included:

S101: the data packet that sender sends is received.

Sender may include: terminal, base station, STA(Station, website), AP(Access Point, access point) with And other network equipments, wherein STA and AP refers to WLAN(Wireless Local Area Networks, wireless access network Network) in equipment, and base station typically refers to the equipment in cellular network, and in the embodiment of the present application, sender is with site STA 1 For.When data packet is that site STA 1 is sent, it is located in the coverage area of site STA 1 due to site STA 3, so website STA3 can receive the data packet of STA1 transmission.When site STA 3 upon reception of the data packet, carry out S102, otherwise terminate.

S102: judge sender whether according to cycle T access channel according to data packet.

In one embodiment, according to data packet judge site STA 1 whether according to cycle T access channel there are many mode, In one embodiment, when site STA 1 is in sending cycle business datum, can carry the period in the data packet of transmission is connect Enter the mark of channel and access the cycle T of channel, and then site STA 3 can be true according to the mark and cycle T that carry in data packet Whether site STA 1 is determined according to cycle T access channel.

In another embodiment, site STA 1 can be arranged specially when sending data packet in the physical header of data packet Whether the data for indicating that site STA 1 is sent with mode bit are periodic traffic data, such as: designation date packet is VoIP (Voice over Internet Protocol, IP phone) data packet, and can be preparatory in site STA 3 Access period T corresponding with periodic traffic data is stored, such as: when data packet is VoIP data packet, access period T= 20ms, and then it may determine that site STA 1 whether according to cycle T access channel.

In another embodiment, site STA 1 can not also carry out any processing to the data packet of transmission, and site STA 3 The feature of data packet be can use to determine whether for periodic traffic data packet, such as: when data packet is VoIP data packet, stand Point STA3 can be by the packet length or MAC(Medium Access Control in physical frame header in data packet, medium access Control) Packet type on head is judged, this is because usually VoIP typically small (only tens Byte), it is possible to be arranged One targets threshold, when the packet for detecting data packet is long is less than the targets threshold, so that it may determine that site STA 1 needs the period Access channel can be obtained in advance and be stored in site STA 3 as access period T.

When described sender accesses channel according to cycle T, S103 is carried out, otherwise, is terminated.

S103: rollback is executed at the t1+nT moment.

Rollback is executed at the t1+nT moment, site STA 3 will stop access channel in the preset duration at t1+nT moment, Site STA 1 is allowed still to be able to period access channel at the t1+nT moment, as shown in figure 3, site STA 1 is sent at the t1 moment Data packet 1, site STA 3 execute rollback at the t1+T moment according to the information of data packet, and then in the subsequent transmission data of site STA 1 When wrapping 2, channel can be smoothly accessed.In addition, in the embodiment of the present application, sender can be base station, STA or AP, such as Fig. 3 institute Show, by taking AP as an example, the data packet that site STA 4 is sent according to access point AP1 at the tp moment executes rollback at the tp+T moment, so as to Access point AP1 can smoothly access channel when sending data packet 4.

The channel access control method provided by the embodiments of the present application covers site STA 3 due to being located at sender Range, in this way when sender is when sending data packet at the t1 moment, site STA 3 can receive the data packet, and STA3 can be with Using the data packet received determine sender whether according to cycle T access channel, and when determine sender connect according to cycle T When entering channel, rollback is executed at the t1+nT moment, and then can guarantee that sender can access channel, execution cycle business with the period Data transmission.

In the application one embodiment, as shown in figure 4, step S102 may include:

S201: it detects in the data packet with the presence or absence of being used to indicate the mark that sender's period accesses channel.

When site STA 1 is in sending cycle business datum, period access channel can be carried in the data packet of transmission Mark and access channel cycle T, site STA 3 can determine website according to the mark and cycle T carried in data packet at this time Whether STA1 is according to cycle T access channel.When there are the mark, S202 is carried out, otherwise, is terminated.

S202: determine that the described sender period accesses channel.

S203: the cycle T that the sender carried in the data packet accesses channel is extracted.

In specific application, mark and cycle T can be located in data packet on same position, such as: when the value of this is 0 When, it indicates that sender accesses channel without the period, when the value of this is other non-zero value, indicates sender according to this 's Value is used as access period, and subsequent periodic accesses channel.In addition, mark and cycle T can also be located on different positions, pass through Whether the value of two positions judges sender according to cycle T access channel jointly.

As shown in figure 5, in another embodiment of the application, step S102 may include:

S301: the packet for detecting the data packet is long.

The value of the long position Lenth for referring to physical frame header in data packet of packet.

S302: judge that the packet is long and whether be less than the default long threshold value of packet.

Site STA 1 can not also carry out any processing to the data packet of transmission, but be determined using the feature of data packet It whether is periodic traffic data packet, such as: it, can be by physical frame header in data packet when data packet is VoIP data packet Packet length judged, this is because usually VoIP data packet is typically small (only tens Byte), it is possible to be arranged one Long threshold value is wrapped, when site STA 3, which detects that the packet of data packet is long, is less than the long threshold value of the packet, so that it may determine 1 needs of site STA Period access channel can obtain in advance as access period T, and be stored in site STA 3.

When the packet is long is less than the long threshold value of default packet, S303 is carried out, otherwise, is terminated.

S303: determine that the described sender period accesses channel.

S304: according to the corresponding relationship of pre-set Bao Changyu access period, the access period T of sender is obtained.

The corresponding relationship of Bao Changyu access period can be preset, as shown in table 1, when the data packet that site STA 1 is sent When for VoIP data packet, can will wrap long threshold value and be set as 100Byte, and will packet long to be less than the corresponding access of 100Byte all Phase is set as 20ms.

Packet length	Access period
		Less than 100Byte	20ms

Table 1

As shown in fig. 6, in the another embodiment of the application, step S102 may include:

S401: the value that reserved bit is preset in the data packet is detected；

S402: judge whether the value of the default reserved bit indicates the data packet for VoIP data packet.

When sending data, single user state position can be arranged, in the physical header of data packet to indicate to send in site STA 1 Data whether be periodic traffic data, such as: designation date packet be VoIP(Voice over Internet Protocol, IP phone) data packet, and access period corresponding with periodic traffic can be stored in advance in site STA 3 T, when data packet is VoIP data packet, access period T=20ms.

When the value of preset reserved bit indicates that the data packet is VoIP data packet, S403 is carried out, otherwise, is terminated.

S403: determine that the described sender period accesses channel.

S404: according to the corresponding relationship of pre-set VoIP data packet and access period, described sender access is obtained The cycle T of channel.

In addition, in a particular application, priority can be set in Fig. 4, Fig. 5 and mode shown in fig. 6, and such as: first check number According to the mark in packet, then detection packet length, finally detects default reserved bit, and certain each embodiment can also individually be implemented.

In the embodiment of the present application, as shown in fig. 7, step S103 method may include:

S501: T- (t2-t1) is set by the duration of Backoff timer；

S502: judging whether n is equal to 1, as n=1, carries out S503；Otherwise, S506 is carried out.

S503: start timing at the t2 moment.

As n=1, indicate that this retracts to retract for the first time.T2 is the finish time of the data packet.

S504: judge whether timing duration is equal to T-(t2-t1), when timing length is equal to T- (t2-t1), carry out Otherwise S505 terminates.

S505: Backoff window is set according to preset duration.

The effect of Backoff window is to control to prolong after the sending instant of data to be sent to after the Backoff window, is avoided The data packet sent with sender's period is collided, and the transmission of periodic traffic data is influenced.

S506: it detects whether to receive data packet at the t1+nT moment.

Channel at the time of point is accessed in subsequent sender's period, if receiving data packet, indicates the period industry of sender Data of being engaged in still are continuing, and carry out S507, otherwise, indicate that the periodic traffic data transmission of sender terminates, carry out S508.

S507: starting timing, and when timing length is equal to T- (t2-t1) after the finish time of each data packet, According to identical preset duration, Backoff window is set.

In the embodiment of the present application, the duration of the Backoff window of rollback setting is identical every time.

S508: the duration of the Backoff timer is reset, and terminates to retract.

When the duration for resetting Backoff timer, timing is no longer carried out at next moment, terminates back off procedure.

In addition, in the embodiment of the present application, after the completion of each retract, site STA 3 needs normally to access channel also with complete It is sent or received at data, as shown in figure 8, this method can also include:

S104: detecting the preset sending instant of data to be sent and occupies duration region.

Here, occupy duration to refer to: data send duration, or, data send duration and receive to the data to be sent The duration of the ACK message fed back.

S105: according to the sending instant and duration region is occupied, judges the occupancy duration region of the data to be sent Whether next Backoff window is covered.

It after site STA 3 executes primary retract, indicates at the subsequent t1+nT moment, sender STA1 is it is possible to access letter Road, if directly transmitting data after site STA 3 executes primary retract, once then the transmission occupancy duration of site STA 3 is more than Next Backoff window, it means that when accessing channel 1 period of site STA next time rollback can not be executed, and then can not Guarantee that sender's site STA 1 accesses channel according to the period, influences the transmission of periodic traffic data.

So it is next to need to judge whether the occupancy duration of data to be sent covers after site STA 3 executes primary rollback Backoff window carries out S106 when covering next Backoff window, when not covering next Backoff window, executes S107, presses According to normal processing mode by data to be sent.

S106: the data to be sent are segmented to obtain multiple segment datas, and determine the hair of each segment data Send the moment.

The sending instant of each segment data makes the occupancy duration region of the segment data not cover next rollback Window.

S107: according to DCF mode or EDCA, (Enhanced Distributed Channel Access, enhancing are distributed Channel access) mode accesses channel, to send segment data or data to be sent.

Fig. 9 is the flow diagram of another channel access control method provided by the embodiments of the present application.

Below by taking site STA 2 as an example, channel access control method provided by the embodiments of the present application is illustrated, such as Fig. 9 It is shown, the channel access control method the following steps are included:

S601: receiving ACK(Acknowledgement, confirms character) message.

ACK message is that the data packet that base station, site STA or access point AP send sender in coverage area is fed back Message.Referring to shown in above-mentioned Fig. 1, ACK message is that access point AP1 carries out the data packet that site STA 1 in coverage area is sent Feedback, and site STA 1 refers in access point AP1 coverage area, and is not located at one kind in 2 coverage area of site STA Website.

S602: judge described sender whether according to cycle T access channel according to the ACK message.

In the embodiment of the present application, according to ACK message judge site STA 1 whether according to cycle T access channel there are many side Formula, in one embodiment, when site STA 1 carries mark and the access week of period access channel in the data packet of transmission Phase T, at this time access point AP1 when generating ACK message, can equally be carried in ACK message the period access channel mark and Access period T, and then site STA 2 can be true according to the mark and access period T of the period access channel carried in data packet Whether site STA 1 is determined according to cycle T access channel.

In another embodiment, single user state can also be arranged in the physical header or MAC header of ACK message in access point AP1 Position, for come indicate the data packet received be periodic traffic data packet, such as: VoIP(Voice over Internet Protocol, IP phone) data packet, and can be stored in advance in site STA 2 corresponding with periodic traffic Access period T, such as: when data packet is VoIP data packet, access period T=20ms, and then according to dedicated in ACK message State is, so that it may judge whether site STA 1 according to cycle T accesses channel.

In another embodiment, access point AP1 can also only in its domain Duration, duplication receives data packet Then a targets threshold is arranged in the domain Duration in site STA 2, when the value for detecting the domain Duration is less than the target When threshold value, so that it may determine that site STA 1 needs period access channel that can obtain in advance as access period T, and store In site STA 2.

When the site STA 1 accesses channel according to cycle T, S603 is carried out, otherwise, is terminated.

S603: in t3+T-Duration+SIFS(Short Inter-Frame Space, short frame interval) moment executes back It moves back.

T3 is the finish time of the ACK message, and the value of Duration can pass through the domain Duration in detection ACK message Value obtain, the value in the domain Duration indicates the sending duration of data packet.In addition, in the embodiment of the present application, rollback Time is preset duration.

It will be noted from fig. 1 that site STA 2 is not located in the coverage area of site STA 1, so using real shown in Fig. 2 When applying the method for example, site STA 2 can not receive the data packet of site STA 1, but since site STA 1 and site STA 2 are located at In same access point AP1 coverage area, so site STA 2 still can be with website in 1 sending cycle business datum of site STA There is channel competition in STA1.

As shown in connection with fig. 10, it is seen then that after site STA 1 sends data packet 1, site STA 2 and STA4 pass through to access point AP1 The ACK message of transmission is detected, and rollback can be executed within the period that site STA 1 sends data packet, guarantees site STA 1 Channel can be smoothly accessed when sending data packet 2.So in this method provided by the embodiments of the present application, by utilizing access point AP1 sends the feeding back ACK message of data packet to site STA 1, can control the site STA 2 in access point coverage area in website It retracts when STA1 sending cycle business datum, guarantees smoothly access channel when sending cycle business datum.

In addition, not being located at the station in access point AP1 coverage area for being neither located in 1 coverage area of site STA yet Point, since it can not interfere with the communication of site STA 1 Yu access point AP1, it is possible to not have to consider this kind of websites.

In the embodiment of the present application, as shown in figure 11, step S602 may include:

S701: it detects in the ACK message with the presence or absence of being used to indicate the mark that sender's period accesses channel.

When detecting that being used to indicate sender's period accesses the mark of channel, S702 is carried out, otherwise, is terminated.

S702: determine that the described sender period accesses channel.

S703: the cycle T of the described sender access channel carried in the ACK message is extracted.

In specific application, mark and cycle T can be located in data packet on same position, such as: when the value of this is 0 When, it indicates that sender accesses channel without the period, when the value of this is other non-zero value, indicates sender according to this 's Value is used as access period, and subsequent periodic accesses channel.In addition, mark and cycle T can also be located on different positions, pass through Whether the value of two positions judges sender according to cycle T access channel jointly.

In another embodiment of the application, as shown in figure 12, step S602 may include:

S801: the value in the domain Duration in the ACK message is detected.

S802: judge whether the value in the domain Duration is less than targets threshold.

The value in the domain Duration indicates the sending duration of data packet.Targets threshold is used to indicate when the domain Duration The data packet that described sender is sent when value is less than targets threshold is VoIP.When the value in the domain Duration is less than targets threshold When, S803 is carried out, otherwise, is terminated.

S803: determine that the described sender period accesses channel.

S804: according to the corresponding relationship of the value in the default domain Duration and access period, described sender access letter is obtained The cycle T in road.

It can be previously stored with the value in the domain Duration and the corresponding relationship of access period in site STA 2, sent out when determining After the side's of sending period accesses channel, it can directly search to obtain the cycle T that sender accesses channel.

In the another embodiment of the application, as shown in figure 13, step S602 may include:

S901: the value that indicating bit is preset in the ACK message is detected.

Whether the data packet that default indicating bit is used to indicate described sender transmission is VoIP data packet.

S902: judge whether the value of the default indicating bit indicates the data packet of described sender transmission for VoIP data Packet.When the data packet for indicating that described sender is sent is VoIP data packet, S903 is carried out, otherwise, is terminated.

S903: determine that the described sender period accesses channel.

S904: the value of default indicating bit according to the pre-stored data and the corresponding relationship of access period obtain described sender Access the cycle T of channel.

In the application implementation, as shown in figure 14, step S603 may include:

S1001: setting T-Duration+SIFS for the duration of Backoff timer, starts timing at the t3 moment；

S1002: when the timing length is equal to the short interframe of T-Duration+SIFS(Short Inter-Frame Space Every) when, according to preset duration, Backoff window is set.

Backoff window is for controlling and prolonging after the sending instant of data to be sent to after the Backoff window.

Figure 15 is a kind of schematic diagram of data packet generation method provided by the embodiments of the present application.This method is applied in network Data packet sending device, such as: any one in terminal, base station, site STA or access point AP, as shown in figure 15, this method May include:

S1101: judge whether data to be sent are periodic traffic data.

When data to be sent are periodic traffic data, S1102 is carried out, otherwise, is terminated.

S1102: the cycle T of the periodic traffic data access channel is obtained.

S1103: the mark of period access channel is generated.

S1104: the data packet of sending cycle business datum includes the mark and cycle T in the data packet.

In another embodiment of the application, when judging data to be sent for periodic traffic data, which is generated Method can also include:

11): judging whether the periodic traffic data are VoIP data；

When the periodic traffic data are VoIP data, 2), otherwise terminate.

12): default reserved bit is selected in the data packet.

Default reserved bit is used to indicate whether data packet is VoIP data packet；

13): the value of the setting default reserved bit.

The value of the default reserved bit indicates that the data packet is VoIP data packet after setting.

Figure 16 is a kind of flow diagram of ACK message forming method provided by the embodiments of the present application.This method can answer With carrying out the network equipment of feedback function to data packet with having, such as: in base station, STA or AP, as shown in figure 16, this method May include:

S1201: it detects in the data packet received and whether accesses the mark of channel comprising the period and access the period of channel T.When the cycle T of the mark and access channel that in the data packet received include period access channel, S1202 is carried out, otherwise Terminate.

S1202: transmission includes the data packet of the ACK message of the mark and cycle T.

In another embodiment of the application, this method can also include:

21): judging whether the data packet received is VoIP data packet.When the data packet received is VoIP data packet When, it carries out 22), otherwise, terminates.

22): the value in the domain Duration in the VoIP data packet is copied into the domain Duration in the ACK message In.

In the another embodiment of the application, when the data packet received is VoIP data packet, this method can also include:

23): default indicating bit is selected in the ACK message.

Default indicating bit, which is used to indicate, receives whether data packet is VoIP data packet.

24): the value of the setting default indicating bit.

The data packet that the value instruction of the default reserved bit receives after setting is VoIP data packet.

By the description of above embodiment of the method, it is apparent to those skilled in the art that the application can Realize by means of software and necessary general hardware platform, naturally it is also possible to by hardware, but in many cases the former It is more preferably embodiment.Based on this understanding, the technical solution of the application substantially makes tribute to the prior art in other words The part offered can be embodied in the form of software products, which is stored in a storage medium, packet Some instructions are included to use so that a computer equipment (can be personal computer, server or the network equipment etc.) executes The all or part of the steps of each embodiment the method for the application.And storage medium above-mentioned includes: read-only memory (ROM), the various media that can store program code such as random-access memory (ram), magnetic or disk.

The embodiment of the present application also provides a kind of channel access control devices, as shown in figure 17, the apparatus may include:

Data receipt unit 11, for receiving the data packet of sender's transmission；

First channel access judging unit 12, for judging described sender whether according to cycle T according to the data packet Access channel；

First rollback control unit 13, for being held at the t1+nT moment when described sender accesses channel according to cycle T Row retracts, wherein n is positive integer, and the initial value of n is the time of reception that 1, t1 is the data packet.

Wherein, in the application one embodiment, the first channel access judging unit may include

First identifier detection unit accesses letter with the presence or absence of being used to indicate sender's period for detecting in the data packet The mark in road；

First channel access determination unit, for when there are the mark, determining that sender's period accesses channel；

Period 1 acquiring unit, for obtaining hair from the data packet after determining that sender's period accesses channel The cycle T of the side's of sending access channel.

In another embodiment of the application, the first channel access judging unit may include:

Long detection unit is wrapped, the packet for detecting the data packet is long；

The value of the long position Lenth for referring to physical frame header in data packet of packet, passes through Lenth values of detection, available number It is long according to the packet of packet.

Long judging unit is wrapped, whether is less than the default long threshold value of packet for judging that the packet is long；

Second channel access determination unit, for determining sender's period when the long long threshold value less than default packet of the packet Access channel；

Usual VoIP data packet is typically small (only tens Byte), so in the embodiment of the present application, presetting the long threshold of packet 100Byte can be set into value.

Second round acquiring unit, for the corresponding relationship according to pre-set Bao Changyu access period, described in acquisition The cycle T of sender's access channel.

In the embodiment of the present application, periodic traffic data packet is by taking VoIP data packet as an example, so being connect according to second channel Entering the judging result of determination unit for that when being, can directly determine the period of the access channel of sender is 20ms.

In another embodiment of the application, the first channel access judging unit may include:

Reserved bit detection unit, for detecting the value for presetting reserved bit in the data packet, the default reserved bit is used for Whether designation date packet is VoIP data packet；The value of default reserved bit can have it is multiple, such as: 1 indicates that data packet is VoIP number Indicate that data packet is not VoIP data packet according to packet, 0.

Third channel access determination unit, for indicating that the data packet is VoIP data packet when the value of the default reserved bit of institute When, determine that sender's period accesses channel；

Period 3 acquiring unit is looked into for the corresponding relationship according to pre-set VoIP data packet and access period Sender is looked for access the cycle T of channel.

In the embodiment of the present application, when determining data packet is with VoIP data packet, connecing for sender can be directly determined The period for entering channel is 20ms.

Wherein, in the application one embodiment, as shown in figure 18, the first rollback control unit 13 may include:

First rollback timing unit 131, for setting the duration of Backoff timer to T- (t2-t1) as n=1, and The t2 moment starts timing, and t2 is the finish time of the data packet；

First Backoff window setting unit 132, for being set according to preset duration when timing length is equal to T- (t2-t1) Backoff window is set, the Backoff window is for controlling and prolonging after the sending instant of data to be sent to after the Backoff window；

Data detecting unit 133, for detecting whether the data receipt unit receives at the t1+nT moment when n is greater than 1 To data packet；

Rollback finishing control unit 134, for not receiving data packet when the data receipt unit described in the t1+nT moment When, the duration of the Backoff timer is reset, terminates to retract；

The first rollback timing unit 131 is also used to when t1+nT reception is to data packet, in each data packet Finish time after start timing, after the first Backoff window setting unit also 132 is used for each data packet finish time When timing length is equal to T- (t2-t1), Backoff window is set according to identical preset duration.

In another embodiment of the application, as shown in figure 19, which can also include:

Data detecting unit 14 to be sent, for detecting the preset sending instant of data to be sent and occupying duration region, The occupancy duration includes: that data send duration, or, data send what duration fed back the data to be sent with reception The duration of ACK message；

Region overlay judging unit 15, for judging described to be sent according to the sending instant and occupancy duration region Whether the occupancy duration region of data covers next Backoff window；

Data segmentation unit 16, for when the judging result of region overlay judging unit be when, by the number to be sent According to being segmented to obtain multiple segment datas, and the sending instant of each segment data is determined, when the transmission of each segment data It carves so that the occupancy duration region of the segment data does not cover next Backoff window；

Channel access unit 17, for accessing EDCA according to distributed coordination function DCF mode or enhancing distributed channel Mode accesses channel, to send the segment data or the data to be sent.

The channel access control device, can be applied in website, such as in site STA shown in FIG. 13, due to being located at The coverage area of sender's site STA 1, in this way when site STA 1 is when sending data packet at the t1 moment, site STA 3 be can receive To the data packet, and STA3 can use the data packet received and determine whether site STA 1 according to cycle T accesses channel, and And when determining that site STA 1 accesses channel according to cycle T, rollback is executed at the t1+nT moment, and then can guarantee site STA 1 Channel, execution cycle business data transmission can be accessed with the period.

The embodiment of the present application also provides another channel access control device, as shown in figure 20, channel access control dress It sets and may include:

Message receiving unit 21, for receiving ACK message, the ACK message is base station, STA or AP in coverage area The data packet that sender sends is fed back, and the information that base station, STA or AP receive data packet can be carried in message, Such as type, Duration of data packet of data packet etc., in addition, base station, STA or AP can also be by the data received Packet detection, default indicating bit is provided in ACK message, is used to indicate the information such as the type of the data packet received；

Whether second channel accesses judging unit 22, for judging described sender according to cycle T according to the ACK message Access channel；

Second rollback control unit 23 is used for when described sender accesses channel according to cycle T, in t3+T- The Duration+ short frame interval SIFS moment executes rollback, wherein t3 is the finish time of the ACK message, and Duration is institute State the value in the domain Duration in ACK message.

Wherein, in the application one embodiment, second channel access judging unit 22 may include:

Second identifier detection unit is accessed for detecting in the ACK message with the presence or absence of being used to indicate sender's period The mark of channel；When carried in the data packet received instruction sender's period access the mark of channel when, base station, STA or AP can copy to the mark in ACK message；

4th channel access determination unit, for when detecting that being used to indicate sender's period accesses the mark of channel, Determine that the described sender period accesses channel；

Period 4 acquiring unit, for being obtained from the ACK message after determining described sender period access channel Take the cycle T of described sender access channel；When carrying sender's period in data packet and accessing the mark of channel, usual number According to the cycle T that can also carry access channel in packet, when base station, STA or AP receive the mark and cycle T of period access channel Data packet when, the mark carried in data packet and cycle T can be copied directly in ACK message.

In another embodiment of the application, second channel accesses judging unit 22, may include:

Packet check unit, for detecting the value in the domain Duration in the ACK message；

Threshold decision unit, for judging whether the value in the domain Duration is less than targets threshold；

5th channel access determination unit, described in determining when the value in the domain Duration is less than targets threshold Sender's period accesses channel；

Period 5 acquiring unit is obtained for the corresponding relationship according to the value and access period for presetting the domain Duration The cycle T of described sender access channel.

In another embodiment of the application, second channel accesses judging unit 22, may include:

Indicating bit detection unit, for detecting the value for presetting indicating bit in the ACK message, the default indicating bit is used for Whether the data packet for indicating that described sender is sent is VoIP data packet；

6th channel access determination unit, the data packet for sending when indicating bit instruction described sender is VoIP When data packet, determine that the described sender period accesses channel；

Period 6 acquiring unit, the value pass corresponding with access period for default indicating bit according to the pre-stored data System obtains the cycle T of described sender access channel.

Wherein, in the application one embodiment, the second rollback control unit includes:

Second rollback timing unit, for setting T-Duration+ short frame interval SIFS for the duration of Backoff timer, Start timing at the t3 moment；

Second Backoff window setting unit is used for when the timing length is equal to T-Duration+SIFS, according to default Backoff window is arranged in duration, and the Backoff window is for controlling and prolonging after the sending instant of data to be sent to the Backoff window Later.

The channel access control device, can be applied in site STA 2, be sent out by detection access point AP1 site STA 1 The feeding back ACK message for sending data packet can control the site STA 2 in access point AP1 coverage area in 1 sending cycle of site STA It retracts when business datum, guarantees that channel can be entered when sending STA1 sending cycle business datum with drop-over.

The embodiment of the present application also provides a kind of terminal, which can also include: such as any corresponding implementation of Figure 17-Figure 19 At least one of the channel access control device in channel access control device and such as Figure 20 corresponding embodiment in example, about The detailed description of channel access control device may refer to the description in above-described embodiment, and details are not described herein.

When terminal has the channel access control device that can be accessed according to data packet control channel simultaneously and can be reported according to ACK When the channel access control device of literary control channel access, by taking Fig. 1 as an example, if terminal is located in the coverage area of STA1, and And terminal is located in the coverage area of access point AP1, then terminal can not only when 1 sending cycle business data packet of site STA The data packet of the transmission of site STA 1 is enough received, and is retracted according to the data packet received, but also can receive access The ACK message that the data packet that point AP1 sends site STA 1 is fed back, and retracted according to the ACK message received, from And can more preferably guarantee site STA 1 can smoothly access channel in sending cycle business data packet.

The embodiment of the present application also provides a kind of terminals, and as shown in figure 21, the terminal includes: receiver 1, transmitter 2 With processor 3, wherein for receiving wireless data, wireless data includes receiver 1: the data packet that other network equipments are sent, Or, the ACK message for being fed back to data packet that other network equipments are sent；Transmitter 2 is for being sent out no line number According to；

On the one hand processor 3 executes following procedure:

Receive the data packet that sender sends；Judge whether described sender accesses according to cycle T according to the data packet Channel；When described sender accesses channel according to cycle T, rollback is executed at the t1+nT moment, wherein n is positive integer, and n's is first Initial value is the time of reception that 1, t1 is the data packet；Also, processor 3 can also be performed in Fig. 2-Fig. 8 corresponding embodiment Step.

On the other hand following procedure can be executed:

Confirmation character ACK message is received, the ACK message is base station, site STA or access point AP to sending out in coverage area The message that the data packet that the side of sending is sent is fed back；Judge whether described sender accesses according to cycle T according to the ACK message Channel；When described sender accesses channel according to cycle T, executed back at the t3+T-Duration+ short frame interval SIFS moment It moves back, wherein t3 is the finish time of the ACK message, and Duration is the value in the domain Duration in the ACK message；Also, The step in Fig. 9-Figure 14 corresponding embodiment can also be performed in processor 3.

It is understood that the application can be used in numerous general or special purpose computing system environments or configuration.Such as: it is a People's computer, server computer, handheld device or portable device, multicomputer system, are based on micro process at laptop device The system of device, set top box, programmable consumer-elcetronics devices, network PC, minicomputer, mainframe computer including to take up an official post The distributed computing environment etc. of what system or equipment.

The application can describe in the general context of computer-executable instructions executed by a computer, such as program Module.Generally, program module includes routines performing specific tasks or implementing specific abstract data types, programs, objects, group Part, data structure etc..The application can also be practiced in a distributed computing environment, in these distributed computing environments, by Task is executed by the connected remote processing devices of communication network.In a distributed computing environment, program module can be with In the local and remote computer storage media including storage equipment.

It should be noted that, in this document, relational terms such as first and second and the like are used merely to a reality Body or operation are distinguished with another entity or operation, are deposited without necessarily requiring or implying between these entities or operation In any actual relationship or order or sequence.Moreover, the terms "include", "comprise" or its any other variant are intended to Non-exclusive inclusion, so that the process, method, article or equipment including a series of elements is not only wanted including those Element, but also including other elements that are not explicitly listed, or further include for this process, method, article or equipment Intrinsic element.In the absence of more restrictions, the element limited by sentence "including a ...", it is not excluded that There is also other identical elements in process, method, article or equipment including the element.

The above is only the specific embodiment of the application, it is noted that for the ordinary skill people of the art For member, under the premise of not departing from the application principle, several improvements and modifications can also be made, these improvements and modifications are also answered It is considered as the protection scope of the application.

Claims (9)

1. a kind of channel access control method, which is characterized in that the described method includes:

Receive the data packet that sender sends；

Judge described sender whether according to cycle T access channel according to the data packet；

When described sender accesses channel according to cycle T, rollback is executed at the t1+nT moment, wherein n is positive integer, and n's is first Initial value is the time of reception that 1, t1 is the data packet；

Wherein, rollback is executed at the t1+nT moment, comprising:

T- (t2-t1) is set by the duration of Backoff timer；

As n=1, start timing at the t2 moment, and when timing length is equal to T- (t2-t1), be arranged back according to preset duration Window is moved back, for controlling and prolonging after the sending instant of data to be sent to after the Backoff window, t2 is the Backoff window The finish time of the data packet；

When n is greater than 1, whether detection receives data packet at the t1+nT moment；

When t1+nT reception is to data packet, start timing after the finish time of each data packet, and when timing is long When degree is equal to T- (t2-t1), Backoff window is set according to identical preset duration；

When not receiving data packet at the t1+nT moment, the duration of the Backoff timer is reset, terminates to retract；

The method also includes:

It detecting the preset sending instant of data to be sent and occupies duration region, the occupancy duration includes: that data send duration, Or, data send duration and receive the duration of the ACK message fed back to the data to be sent；

According to the sending instant and duration region is occupied, judges whether the occupancy duration region of the data to be sent covers down One Backoff window；

When the next Backoff window of the occupancy duration region overlay of the data to be sent, the data to be sent are divided Section obtains multiple segment datas, and determines the sending instant of each segment data, and the sending instant of each segment data makes this The occupancy duration region of segment data does not cover next Backoff window；

Channel is accessed according to distributed coordination function DCF mode or enhancing distributed channel access EDCA mode, described in sending Segment data；

When the occupancy duration region of the data to be sent does not cover next Backoff window, according to distributed coordination function DCF mode or enhancing distributed channel access EDCA mode access channel, to send the data to be sent.

2. the method according to claim 1, wherein according to the data packet judge described sender whether according to Cycle T accesses channel, comprising:

It detects in the data packet with the presence or absence of the mark for being used to indicate described sender period access channel；

When there are the mark, determine that the described sender period accesses channel；

Extract the cycle T that the sender carried in the data packet accesses channel.

3. the method according to claim 1, wherein according to the data packet judge described sender whether according to Cycle T accesses channel, comprising:

The packet for detecting the data packet is long；

Judge that the packet is long and whether is less than the default long threshold value of packet；

When the packet is long is less than the long threshold value of default packet, determine that the described sender period accesses channel；

According to the corresponding relationship of pre-set Bao Changyu access period, the cycle T of described sender access channel is obtained.

4. the method according to claim 1, wherein according to the data packet judge described sender whether according to Cycle T accesses channel, comprising:

The value that reserved bit is preset in the data packet is detected, the default reserved bit is used to indicate whether data packet is internet protocol Discuss phone VoIP data packet；

When the value of preset reserved bit indicates that the data packet is VoIP data packet, described sender period access letter is determined Road；

According to the corresponding relationship of pre-set VoIP data packet and access period, the period of described sender access channel is obtained T。

5. a kind of channel access control device characterized by comprising

Data receipt unit, for receiving the data packet of sender's transmission；

First channel access judging unit is believed for judging whether described sender accesses according to cycle T according to the data packet Road；

First rollback control unit, for executing rollback at the t1+nT moment when described sender accesses channel according to cycle T, Wherein, n is positive integer, and the initial value of n is the time of reception that 1, t1 is the data packet；

The first rollback control unit includes:

First rollback timing unit, for setting T- (t2-t1) for the duration of Backoff timer as n=1, and at the t2 moment Start timing, t2 is the finish time of the data packet；

First Backoff window setting unit, for rollback window to be arranged according to preset duration when timing length is equal to T- (t2-t1) Mouthful, the Backoff window is for controlling and prolonging after the sending instant of data to be sent to after the Backoff window；

Data detecting unit, for when n is greater than 1, whether detection data receipt unit described in the t1+nT moment to receive data Packet；

Rollback finishing control unit will be described for when the data receipt unit described in the t1+nT moment does not receive data packet The duration of Backoff timer is reset, and terminates to retract；

The first rollback timing unit is also used to when t1+nT reception is to data packet, in the end of each data packet Start timing after moment, the first Backoff window setting unit is also used to the timing length etc. after each data packet finish time When T- (t2-t1), Backoff window is set according to identical preset duration；

Described device further include:

Data detecting unit to be sent, it is described to account for for detecting the preset sending instant of data to be sent and occupying duration region Include: that data send duration with duration, is reported or, data send duration and receive the ACK fed back to the data to be sent The duration of text；

Region overlay judging unit, for judging the data to be sent according to the sending instant and occupancy duration region Occupy whether duration region covers next Backoff window；

Data segmentation unit, for when the judging result of region overlay judging unit, which is, is, the data to be sent to be carried out Segmentation obtains multiple segment datas, and determines the sending instant of each segment data, and the sending instant of each segment data makes The occupancy duration region of the segment data does not cover next Backoff window；

Channel access unit, for being connect according to distributed coordination function DCF mode or enhancing distributed channel access EDCA mode Enter channel, to send the segment data or the data to be sent.

6. device according to claim 5, which is characterized in that the first channel access judging unit includes:

First identifier detection unit is used to indicate described sender period access letter for detecting to whether there is in the data packet The mark in road；

First channel access determination unit, for when there are the mark, determining that the described sender period accesses channel；

Period 1 acquiring unit accesses the cycle T of channel for extracting the sender carried in the data packet.

7. device according to claim 5, which is characterized in that the first channel access judging unit includes:

Long detection unit is wrapped, the packet for detecting the data packet is long；

Long judging unit is wrapped, whether is less than the default long threshold value of packet for judging that the packet is long；

Second channel access determination unit, for determining that sender's period is accessed when the long long threshold value less than default packet of the packet Channel；

Second round acquiring unit obtains the transmission for the corresponding relationship according to pre-set Bao Changyu access period The cycle T of side's access channel.

8. device according to claim 5, which is characterized in that the first channel access judging unit includes:

Reserved bit detection unit, for detecting the value for presetting reserved bit in the data packet, the default reserved bit is used to indicate Whether data packet is IP phone VoIP data packet；

Third channel access determination unit, for when the value of preset reserved bit indicates that the data packet is VoIP data packet, Determine that the described sender period accesses channel；

Period 3 acquiring unit obtains institute for the corresponding relationship according to pre-set VoIP data packet and access period State the cycle T that sender accesses channel.

9. a kind of terminal, which is characterized in that including the described in any item channel access control devices of such as claim 5-8.