CN105101453A - Carrier sensing method based on dynamic idle channel assessment threshold - Google Patents
Carrier sensing method based on dynamic idle channel assessment threshold Download PDFInfo
- Publication number
- CN105101453A CN105101453A CN201510407868.8A CN201510407868A CN105101453A CN 105101453 A CN105101453 A CN 105101453A CN 201510407868 A CN201510407868 A CN 201510407868A CN 105101453 A CN105101453 A CN 105101453A
- Authority
- CN
- China
- Prior art keywords
- node
- rts
- grouping
- cts
- channel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 15
- 230000005540 biological transmission Effects 0.000 claims abstract description 43
- 239000000284 extract Substances 0.000 claims description 16
- 238000000605 extraction Methods 0.000 claims description 11
- 230000002860 competitive effect Effects 0.000 claims description 10
- 238000000205 computational method Methods 0.000 claims description 6
- 238000005562 fading Methods 0.000 claims description 6
- 108090000623 proteins and genes Proteins 0.000 claims description 4
- 238000004891 communication Methods 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 230000007812 deficiency Effects 0.000 description 2
- 101100172132 Mus musculus Eif3a gene Proteins 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000003750 conditioning effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W74/00—Wireless channel access
- H04W74/08—Non-scheduled access, e.g. ALOHA
- H04W74/0808—Non-scheduled access, e.g. ALOHA using carrier sensing, e.g. carrier sense multiple access [CSMA]
- H04W74/0816—Non-scheduled access, e.g. ALOHA using carrier sensing, e.g. carrier sense multiple access [CSMA] with collision avoidance
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Mobile Radio Communication Systems (AREA)
- Small-Scale Networks (AREA)
Abstract
The invention provides a carrier sensing method based on a dynamic idle channel assessment threshold. According to the method, the existing carrier sensing mechanism is improved, and a CCA (Clear Channel Assessment) threshold is adjusted and an effective range of an NAV (Network Allocation Vector) is controlled according to the channel condition, so that the concurrent transmission in a network is increased and the network throughput is improved. According to the method, the CCA threshold is dynamically computed and adjusted according to the receiving power, so that the spatial reuse of the network can be effectively improved, meanwhile, through carrying an interference margin and a probability of acceptance at a CTS (Clear To Send) group, the range of action of the NAV in the CTS group is effectively controlled, and the spatial reuse is further improved, so that the network throughput is improved.
Description
Technical field
The present invention relates to communication technical field, especially a kind of carrier sensing method.
Background technology
WLAN (wireless local area network) (WLAN) adopts usually based on carrier sense multiple access/conflict avoidance (CSMA/CA, CarrierSenseMultipleAccesswithCollisionAvoidance) distributed coordination function (DCF, DistributedCoordinationFunction) mode accesses.DCF adopts Physical carrier sense and virtual carrier sensing in wireless network communication two kinds of carrier sense mechanism to detect channel busy.Only have two kinds of machine-processed channel detection result to be the spare time, node just thinks that channel is not busy, otherwise thinks channel busy.Wherein, Physical carrier sense adopts fixing clear channel assessment (CCA) CCA thresholding, node listens channel, if nodal test to energy exceed clear channel assessment (CCA) ClearChannelAssessment (CCA) thresholding, then think channel busy, otherwise then think channel idle; Virtual carrier sensing in wireless network communication is then: node carries the duration information of this transmission at medium access control MAC (MediaAccessControl) packet header of transmission grouping, i.e. network allocation vector NAV (NetworkAllocationVector) information, if other nodes extract this NAV information, then think channel busy within this period.
Along with popularizing of smart machine and enriching of wireless application, the phenomenon of overlay cells becomes more and more general, and existing carrier sense mechanism all significantly limit (comprising Physical carrier sense and virtual carrier sensing in wireless network communication) performance of WLAN.On the one hand, fixing CCA thresholding determines concurrent transmission number to a great extent, cannot adjust neatly according to network condition.On the other hand, because the control frame coverage of carrying NAV information is often comparatively large, therefore once Node extraction goes out NAV information, and unconditionally accepts this NAV information, then channel booking will be caused too conservative.
Therefore, for the deficiency of existing carrier sense mechanism, the present invention proposes a kind of carrier sensing method based on dynamic CCA thresholding.The method has following two features: (1) receiving node sends the CCA thresholding of the received power dynamic conditioning self that (RTS, RequestToSend) divides into groups according to request; (2) if node receives clear to send CTS (ClearToSend) grouping that destination address is not self, then the NAV information whether accepted in this CTS frame is determined according to the jamming margin comprised in CTS grouping received power and CTS frame and acceptance probability information.The method is improved Physical carrier sense mechanism and virtual carrier sense mechanism simultaneously, improves space reuse degree, thus promotes network throughput.
Summary of the invention
In order to overcome the deficiencies in the prior art, the present invention is intended to improve existing carrier sense mechanism, according to channel status adjustment CCA thresholding and control NAV effective range, thus increases the concurrent transmission in network, improves network throughput.
The carrier sensing method that the present invention proposes is intended to the concurrent transmission increasing network, improves the space reuse degree of network, is therefore specially adapted to the WLAN scene of multiple Basic Service Set BSS (BasicServiceSet).When WLAN dense deployment, certain region memory is at multiple BSS, and each BSS is made up of a corresponding access point AP (AccessPoint) and several site STA (Station) respectively.Consider that the DATA transmission rate collection of all node supports in general WLAN is designated as r
1, r
2... r
n, and r
1< r
2< ... < r
n, corresponding received signal to noise ratio threshold value is SINRth
1, SINRth
2... SINRth
n, and SINRth
1< SINRth
2< ... < SINRth
n, for transmission rate r
i(i=1,2 ... n), only have received signal to noise ratio to be more than or equal to corresponding received signal to noise ratio thresholding SINRth
i(i=1,2 ... n), receiving node could correctly receive transmitted packet with corresponding speed.
The technical solution adopted for the present invention to solve the technical problems is:
Step 1: the node having data to send in multiple Basic Service Set BSS (BasicServiceSet), comprise access point AP node and site STA node, according to IEEE802.11 distributed coordination function DCF (DistributedCoordinationFunction) with binary exponential backoff mode competitive channel, if multiple sending node keeps out of the way end in a time slot simultaneously, clash, all nodes clashed intercept channel again according to IEEE802.11DCF mechanism, and again with binary exponential backoff mode competitive channel, until have and only have a sending node to keep out of the way, then proceed to step 2, do not complete the node kept out of the way to keep out of the way according to IEEE802.11DCF mechanism time-out,
Step 2: sending node produces according to IEEE802.11 standard and sends RTS grouping (RequestToSend, request sends grouping), and proceeds to step 3;
Step 3: the received power P of definition RTS grouping
rts, the received signal to noise ratio SINR of definition RTS grouping
realfor calculating dynamic idle channel estimating CCA (ClearChannelAssessment) thresholding and interference power, receiving node is when receiving RTS grouping, and physical layer can measure received power and the received signal to noise ratio of RTS grouping in real time, the received power P of therefore RTS grouping
rtswith received signal to noise ratio SINR
realcan read and record from physical layer, the all nodes being positioned at RTS transmission range receive this RTS and divide into groups, and RTS is analyzed, the destination address field (DAF) that each Node extraction RTS comprises in dividing into groups, if destination address does not mate with medium access control MAC (MediaAccessControl) address of this node, then extract the duration Duration field comprised in RTS grouping, and according to IEEE802.11 standard configuration network allocation vector NAV, namely in this Duration duration, virtual carrier sense mechanism indicating channel hurries, this node suspends according to IEEE802.11DCF mechanism to be kept out of the way, if destination address mates with the medium access control MAC Address of this node, then receiving node for the purpose of this node, the received power P that object receiving node record RTS divides into groups
rtswith received signal to noise ratio SINR
real, and proceed to step 4,
Step 4: receiving node calculates dynamic CCA threshold value CCA
thwith interference power P
i, and proceed to step 5, dynamic CCA threshold value CCA
thfor:
CCA
th＝P
rts-SINR
*(1)
Wherein formula (1) Zhong Ge variable unit is dB, wherein SINR
*for the fixing signal-noise ratio threshold value preset, this threshold value and channel fading factor-related, the channel fading factor is larger, and signal-noise ratio threshold value is larger, SINR
*random value between [15,25], suggestion SINR
*the desirable SINR of value
*=20, interference power P
ifor:
P
i＝P
rts-SINR
real(2)
Step 5: the received signal to noise ratio that definition signal to noise ratio Dynamic gene k expects in order to adjustment, k is value between [0,1], and degree β is in order to judge the annoyance level of channel for definition channel disturbance, definition maximum channel annoyance level β
maxin order to determine the maximum channel interference that receiving node allows, RTS received signal to noise ratio P
rtslarger, then maximum channel annoyance level β
maxlarger, and meet relation: β
max=P
rts-SINRth
1, wherein SINRth
1for minimum received signal to noise ratio threshold value, channel disturbance degree β is at [0, β
max] random value, the CCA threshold value CCA that receiving node calculates according to step 4
thwith interference power P
imake the following judgment:
If a) P
i≤ CCA
th, then k=0.5 is set, if P
i> CCA
th, and P
i-CCA
th≤ β, then arrange k=1, and proceed to step 6;
If b) P
i> CCA
th, and P
i-CCA
th> β, receiving node does not reply clear to send CTS (ClearToSend) grouping, proceeds to step 12;
Step 6: the DATA transmission rate of node support is designated as r
1, r
2... r
n, and r
1< r
2< ... < r
n, corresponding received signal to noise ratio threshold value is SINRt
1, hSINRt
2h ... SINRt
nh, and SINRth
1< SINRth
2< ... < SINRth
n, for transmission rate r
i(i=1,2 ... n), only have received signal to noise ratio to be more than or equal to corresponding received signal to noise ratio thresholding SINRth
i(i=1,2 ... n), receiving node could correctly receive transmitted packet with corresponding speed;
Receiving node calculates three variablees, i.e. DATA packet rates, jamming margin and acceptance probability, and first receiving node selects the expectation received signal to noise ratio value received when data DATA (data) divides into groups to be SINR
desired,
SINR
desired＝SINR
*+k*(SINR
real-SINR
*)
Then DATA speed r is determined by the following method:
If SINRth
i≤ SINR
desired< SINRth
i+1, then r=r
i, wherein SINRth
ifor DATA transmission rate r
icorresponding received signal to noise ratio thresholding, SINRth
i+1for DATA transmission rate r
i+1corresponding received signal to noise ratio thresholding, i=1,2 ... n-1; If SINR
desired>=SINRth
n, then r=r
n, wherein SINRth
nfor maximum DATA transmission rate r
ncorresponding received signal to noise ratio thresholding;
Jamming margin P
ccomputational methods be:
P
c＝P
rts/SINR
desired-P
i
The computational methods of acceptance probability p are:
If this receiving node receives the RTS grouping that sending node sends first, then arranging acceptance probability is p
0, p
0random value between [0,1]; If this receiving node is not the RTS grouping receiving sending node transmission first, and the front acceptance probability once receiving the rear setting of RTS grouping is p
lastif the front DATA that once correctly receives divides into groups, then the acceptance probability reducing this is p=p
last-Δ p, if p < 0, then arranges p=0, and once correctly do not receive DATA grouping if front, then the acceptance probability improving this is p=p
last+ Δ p, if p > 1, then arranges p=1, and Δ p is acceptance probability adjustment amount, need preset, Δ p can between (0,1) random value, suggestion Δ p value desirable Δ p=0.1, proceeds to step 7 afterwards;
Step 7: receiving node builds CTS grouping, CTS packet format of the present invention with the addition of 3 fields on IEEE802.11 criteria field basis, comprise DATA packet rates field 3 bit, jamming margin field 10 bit and acceptance probability field 3 bit, receiving node is by DATA speed r, jamming margin P
cbe filled into DATA speed field, jamming margin field and the acceptance probability field in CTS grouping respectively with acceptance probability p, all the other fields of CTS grouping are arranged according to IEEE802.11 standard, proceed to step 8 afterwards;
Step 8: receiving node replys CTS grouping, proceeds to step 9 afterwards;
Step 9: all nodes being positioned at CTS transmission range receive this CTS and divide into groups, and CTS is analyzed, the destination address field (DAF) that each Node extraction CTS comprises in dividing into groups, if medium access control MAC (MediaAccessControl) matching addresses of destination address and this node, then this node is source sending node, the DATA speed field that sending node divides into groups from CTS extracts DATA packet rates r, sends DATA grouping, proceed to step 10 afterwards according to DATA packet rates r; If destination address does not mate with medium access control MAC (MediaAccessControl) address of this node, then the received power P of this nodes records CTS grouping
cts, proceed to step 11 afterwards;
Step 10: sending node wait-receiving mode node reverts back confirms ACK (Acknowledgement) grouping, if receive ACK grouping, then the end of transmission, otherwise with binary exponential backoff mode competitive channel, to retransmit;
Step 11: the jamming margin field that other nodes divide into groups from CTS extracts jamming margin information P
c, acceptance probability field extracts acceptance probability information p, and makes following judgement:
If P
cts≤ P
c, then node produces the random number p between [0,1]
randif, p
rand>=p, then this node does not accept the NAV information in CTS grouping, proceed to step 12, otherwise, the duration Duration field that this Node extraction CTS comprises in dividing into groups, according to IEEE802.11 standard configuration network allocation vector NAV, namely in this Duration duration, virtual carrier sense mechanism indicating channel hurries, and this node suspends according to IEEE802.11DCF mechanism to be kept out of the way;
Step 12: node does not accept the NAV information of receiving node, then virtual carrier sense mechanism indicating channel is idle, if node is positioned at the Physical carrier sense scope of sending node, then Physical carrier sense mechanism indicating channel hurries, and this node suspends according to IEEE802.11DCF mechanism to be kept out of the way; If node is positioned at outside the Physical carrier sense scope of sending node, then Physical carrier sense mechanism indicating channel is idle, and now this node can continue to keep out of the way, and has kept out of the way rear access channel, thus transmit concurrent efforts simultaneously with existing, improve the space reuse degree of network.
The invention has the beneficial effects as follows according to received power dynamic calculation and adjustment CCA thresholding, effectively can improve the space reuse degree of network, simultaneously by carrying jamming margin and acceptance probability in CTS grouping, effectively control CTS divide into groups in the sphere of action of NAV, improve space reuse degree further, thus promote network throughput.
Accompanying drawing explanation
Fig. 1 is a kind of typical concurrent transmission scene of the present invention, and its interior joint A and Node B belong to BSS1, and node C and node D belongs to BSS2, and A and C is AP node, B and D is STA node, and wherein BSS is BasicServiceSet, AP is access point AccessPoint, STA is website Station.
Fig. 2 is the sequential chart of embodiment of the present invention interior joint, wherein SIFS is short interFrameGap ShortInter-frameSpace, DIFS is distributed interframe gap (DistributedInter-frameSpace), Busy represents that carrier sense mechanism (comprising Physical carrier sense mechanism and virtual carrier sense mechanism) indicating channel does, backoff keeps out of the way, namely node is carrying out binary exponential backoff, ACK is for confirming Acknowledgement, RTS is request transmission RequestToSend, CTS is clear to send ClearToSend, NAV (CTS) represents the NAV information of instruction in CTS grouping, CTS grouping with the addition of three fields, comprise DATA speed r, jamming margin P
cwith acceptance probability p.
Fig. 3 is the Reference Design of CTS frame format of the present invention, and wherein NAV is that network allocation vector NetworkAllocationVector, CTS frame comprises frame control field 2 byte, channel control field 2 byte, NAV field 2 byte, destination address field 6 byte, frame check field 4 byte; Wherein channel control field can be subdivided into again DATA speed field 3 bit, jamming margin field 10 bit and acceptance probability field 3 bit.
Embodiment
Below in conjunction with drawings and Examples, the present invention is further described.
The present invention can be realized by firmware in wireless network card, or realizes among the driver of wireless network card.Below in conjunction with example, realization of the present invention is described in detail.
Consider that certain region memory is at two BSS, BSS1 and BSS2.Each BSS is by an access point (AP, AccessPoint) and several websites (STA, Station) composition, the AP node of BSS1 is designated as A, certain STA node in it is designated as B, and the AP node of BSS2 is designated as C, and certain the STA node in it is designated as D.Node A wants to send data to Node B, and node C wants to send data to node D.The DATA transmission rate collection that in network, all nodes are supported is identical, is r
1, r
2..r.
n, and r
1< r
2< ... < r
n, corresponding received signal to noise ratio threshold value is SINRth
1, SINRth
2... SINRth
n, and SINRth
1< SINRth
2< ... < SINRth
n.For transmission rate r
i(i=1,2 ... n), only have received signal to noise ratio to be more than or equal to corresponding received signal to noise ratio thresholding SINRth
i(i=1,2 ... time n), receiving terminal could correctly receive.
Step 1: the node having data to send in multiple Basic Service Set BSS (BasicServiceSet), comprise access point AP node and site STA node, according to IEEE802.11 distributed coordination function DCF (DistributedCoordinationFunction) with binary exponential backoff mode competitive channel, if multiple sending node keeps out of the way end in a time slot simultaneously, clash, all nodes clashed intercept channel again according to IEEE802.11DCF mechanism, and again with binary exponential backoff mode competitive channel, until have and only have a sending node to keep out of the way, then proceed to step 2, do not complete the node kept out of the way to keep out of the way according to IEEE802.11DCF mechanism time-out,
Network scenarios can with reference to figure 1, the node having data to send in two BBS, i.e. node A and node C, and according to IEEE802.11 distributed coordination function DCF with binary exponential backoff mode competitive channel, first sending node A has kept out of the way, then proceed to step 2;
Step 2: sending node produces according to IEEE802.11 standard and sends RTS grouping (RequestToSend, request sends grouping), and proceeds to step 3;
Sending node A produces according to IEEE802.11 standard and sends RTS grouping, and its destination address is Node B, proceeds to step 3 afterwards;
Step 3: the received power P of definition RTS grouping
rts, the received signal to noise ratio SINR of definition RTS grouping
realfor calculating dynamic idle channel estimating CCA (ClearChannelAssessment) thresholding and interference power, receiving node is when receiving RTS grouping, and physical layer can measure received power and the received signal to noise ratio of RTS grouping in real time, the received power P of therefore RTS grouping
rtswith received signal to noise ratio SINR
realcan read and record from physical layer, the all nodes being positioned at RTS transmission range receive this RTS and divide into groups, and RTS is analyzed, the destination address field (DAF) that each Node extraction RTS comprises in dividing into groups, if destination address does not mate with medium access control MAC (MediaAccessControl) address of this node, then extract the duration Duration field comprised in RTS grouping, and according to IEEE802.11 standard configuration network allocation vector NAV, namely in this Duration duration, virtual carrier sense mechanism indicating channel hurries, this node suspends according to IEEE802.11DCF mechanism to be kept out of the way, if destination address mates with the medium access control MAC Address of this node, then receiving node for the purpose of this node, the received power P that object receiving node record RTS divides into groups
rtswith received signal to noise ratio SINR
real, and proceed to step 4,
Concrete steps are as follows:
Step 3.1: all nodes being positioned at RTS transmission range receive this RTS and divide into groups, and RTS is analyzed, the destination address field (DAF) that each Node extraction RTS comprises in dividing into groups, if destination address does not mate with the medium access control MAC Address of this node, then extract the duration Duration field comprised in RTS grouping, and according to IEEE802.11 standard configuration network allocation vector NAV, namely in this Duration duration, virtual carrier sense mechanism indicating channel hurries, node once acknowledgement channel is busy, then suspends according to IEEE802.11DCF mechanism and keeps out of the way;
Step 3.2: if destination address mates with the medium access control MAC Address of this node, i.e. Node B, then Node B is by received power P measured when receiving RTS grouping for physical layer
rtswith received signal to noise ratio SINR
realrecord, proceed to step 4 afterwards; Such as, received power P
rts=-40dB, received signal to noise ratio SINR
real=25dB;
Step 4: receiving node calculates dynamic CCA threshold value CCA
thwith interference power P
i, and proceed to step 5, dynamic CCA threshold value CCA
thfor:
CCA
th＝P
rts-SINR
*(1)
Wherein formula (1) Zhong Ge variable unit is dB, wherein SINR
*for the fixing signal-noise ratio threshold value preset, this threshold value and channel fading factor-related, the channel fading factor is larger, and signal-noise ratio threshold value is larger, SINR
*random value between [15,25], suggestion SINR
*the desirable SINR of value
*=20, interference power P
ifor:
P
i＝P
rts-SINR
real(2)
Receiving node B calculates dynamic CCA threshold value CCA
thwith interference power P
i, dynamic CCA threshold value CCA
thfor:
CCA
th＝P
rts-SINR
*
Wherein SINR
*the desirable SINR of value
*=20.
Calculate interference power P
imethod be:
P
i＝P
rts-SINR
real
Proceed to step 5 afterwards.Such as, SINR is got
*=20dB, then dynamic CCA threshold value CCA
th=-40-20=-60dB, interference power P
i=-40-25=-65dB.
Step 5: the received signal to noise ratio that definition signal to noise ratio Dynamic gene k expects in order to adjustment, k is value between [0,1], and degree β is in order to judge the annoyance level of channel for definition channel disturbance, definition maximum channel annoyance level β
maxin order to determine the maximum channel interference that receiving node allows, RTS received signal to noise ratio P
rtslarger, then maximum channel annoyance level β
maxlarger, and meet relation: β
max=P
rts-SINRth
1, wherein SINRth
1for minimum received signal to noise ratio threshold value, channel disturbance degree β is at [0, β
max] random value, the CCA threshold value CCA that receiving node calculates according to step 4
thwith interference power P
imake the following judgment:
If a) P
i≤ CCA
th, then k=0.5 is set, if P
i> CCA
th, and P
i-CCA
th≤ β, then arrange k=1, and proceed to step 6;
If b) P
i> CCA
th, and P
i-CCA
th> β, receiving node does not reply CTS grouping, proceeds to step 12;
Such as, the dynamic CCA threshold value calculated of step 4 and interference power are respectively CCA
th=-60dB, P
i=-65dB, meets P
i≤ CCA
th, then k=0.5 is set, and replys CTS grouping, and proceed to step 6.
Step 6: the DATA transmission rate of node support is designated as r
1, r
2... r
n, and r
1< r
2< ... < r
n, corresponding received signal to noise ratio threshold value is SINRt
1, hSINRt
2h ... SINRt
nh, and SINRth
1< SINRth
2< ... < SINRth
n, for transmission rate r
i(i=1,2 ... n), only have received signal to noise ratio to be more than or equal to corresponding received signal to noise ratio thresholding SINRth
i(i=1,2 ... n), receiving node could correctly receive transmitted packet with corresponding speed;
Receiving node calculates three variablees, i.e. DATA packet rates, jamming margin and acceptance probability, and first receiving node selects the expectation received signal to noise ratio value received when data DATA (data) divides into groups to be SINR
desired,
SINR
desired＝SINR
*+k*(SINR
real-SINR
*)
Then DATA speed r is determined by the following method:
If SINRth
i≤ SINR
desired< SINRth
i+1, then r=r
i, wherein SINRth
ifor DATA transmission rate r
icorresponding received signal to noise ratio thresholding, SINRth
i+1for DATA transmission rate r
i+1corresponding received signal to noise ratio thresholding, i=1,2 ... n-1; If SINR
desired>=SINRth
n, then r=r
n, wherein SINRth
nfor maximum DATA transmission rate r
ncorresponding received signal to noise ratio thresholding;
Jamming margin P
ccomputational methods be:
P
c＝P
rts/SINR
desired-P
i
The computational methods of acceptance probability p are:
If this receiving node receives the RTS grouping that sending node sends first, then arranging acceptance probability is p
0, p
0random value between [0,1]; If this receiving node is not the RTS grouping receiving sending node transmission first, and the front acceptance probability once receiving the rear setting of RTS grouping is p
lastif the front DATA that once correctly receives divides into groups, then the acceptance probability reducing this is p=p
last-Δ p, if p < 0, then arranges p=0, and once correctly do not receive DATA grouping if front, then the acceptance probability improving this is p=p
last+ Δ p, if p > 1, then arranges p=1, and Δ p is acceptance probability adjustment amount, need preset, Δ p can between (0,1) random value, suggestion Δ p value desirable Δ p=0.1, proceeds to step 7 afterwards;
Such as, the signal to noise ratio Dynamic gene that step 5 is calculated is k=0.5, then expect that received signal to noise ratio value is SINR
desired=20+0.5* (25-20)=22.5dB, according to IEEE802.11a standard, transmission rate is the signal-noise ratio threshold that 36Mbps is corresponding is 18.8dB, and transmission rate is the signal-noise ratio threshold that 48Mbps is corresponding is 24.05dB, therefore selects DATA speed to be r=36Mbps.Jamming margin P
c=-40-22.5-(-65)=2.5dB, the acceptance probability value arranged during front once reply CTS grouping is p
last=0.5, acceptance probability adjustment amount is set to Δ p=0.1, if last time transmission success, then acceptance probability p=0.5-0.1=0.4.
Step 7: receiving node builds CTS grouping, CTS frame format can with reference to figure 3, CTS packet format of the present invention with the addition of 3 fields on IEEE802.11 criteria field basis, comprise DATA packet rates field 3 bit, jamming margin field 10 bit and acceptance probability field 3 bit, receiving node is by DATA speed r, jamming margin P
cbe filled into DATA speed field, jamming margin field and the acceptance probability field in CTS grouping respectively with acceptance probability p, all the other fields of CTS grouping are arranged according to IEEE802.11 standard, proceed to step 8 afterwards;
Step 8: receiving node replys CTS grouping, proceeds to step 9 afterwards;
Step 9: all nodes being positioned at CTS transmission range receive this CTS and divide into groups, and CTS is analyzed, the destination address field (DAF) that each Node extraction CTS comprises in dividing into groups, if medium access control MAC (MediaAccessControl) matching addresses of destination address and this node, then this node is source sending node, the DATA speed field that sending node divides into groups from CTS extracts DATA packet rates r, sends DATA grouping, proceed to step 10 afterwards according to DATA packet rates r; If destination address does not mate with medium access control MAC (MediaAccessControl) address of this node, then the received power P of this nodes records CTS grouping
cts, proceed to step 11 afterwards;
Such as, the DATA packet rates r=36Mbps that node A extracts, then send DATA grouping with the speed of 36Mbps to Node B.The received power P of CTS grouping
cts=-50dB.
Step 10: sending node wait-receiving mode node reverts back confirms ACK (Acknowledgement) grouping, if receive ACK grouping, the then end of transmission, otherwise with binary exponential backoff mode competitive channel, to retransmit, the access sequential of sending node A and receiving node B can with reference to figure 2;
Step 11: the jamming margin field that other nodes divide into groups from CTS extracts jamming margin information P
c, acceptance probability field extracts acceptance probability information p, and makes following judgement:
If P
cts≤ P
c, then node produces the random number p between [0,1]
randif, p
rand>=p, then this node does not accept the NAV information in CTS grouping, proceed to step 12, otherwise, the duration Duration field that this Node extraction CTS comprises in dividing into groups, according to IEEE802.11 standard configuration network allocation vector NAV, namely in this Duration duration, virtual carrier sense mechanism indicating channel hurries, and this node suspends according to IEEE802.11DCF mechanism to be kept out of the way;
Step 12: node does not accept the NAV information of receiving node, then virtual carrier sense mechanism indicating channel is idle, if node is positioned at the Physical carrier sense scope of sending node, then Physical carrier sense mechanism indicating channel hurries, and this node suspends according to IEEE802.11DCF mechanism to be kept out of the way; If node is positioned at outside the Physical carrier sense scope of sending node, then Physical carrier sense mechanism indicating channel is idle, and now this node can continue to keep out of the way, and has kept out of the way rear access channel, thus transmit concurrent efforts simultaneously with existing, improve the space reuse degree of network.
Such as, node C to divide into groups the jamming margin P that extracts from CTS
c=2.5dB, acceptance probability information p=0.4.Then there is P
cts(-50dB) < P
c(2.5dB), therefore need to produce random number p
rand=0.7.Due to p
rand> p, then node C does not accept this NAV information, continues to intercept channel according to IEEE802.11DCF mechanism.The access sequential of sending node C and receiving node D can with reference to figure 2.
Claims (1)
1., based on a carrier sensing method for dynamic idle channel assessment threshold, it is characterized in that comprising the steps:
Step 1: the node having data to send in multiple Basic Service Set BSS (BasicServiceSet), comprise access point AP node and site STA node, according to IEEE802.11 distributed coordination function DCF (DistributedCoordinationFunction) with binary exponential backoff mode competitive channel, if multiple sending node keeps out of the way end in a time slot simultaneously, clash, all nodes clashed intercept channel again according to IEEE802.11DCF mechanism, and again with binary exponential backoff mode competitive channel, until have and only have a sending node to keep out of the way, then proceed to step 2, do not complete the node kept out of the way to keep out of the way according to IEEE802.11DCF mechanism time-out,
Step 2: sending node produces according to IEEE802.11 standard and sends RTS grouping (RequestToSend, request sends grouping), and proceeds to step 3;
Step 3: the received power P of definition RTS grouping
rts, the received signal to noise ratio SINR of definition RTS grouping
realfor calculating dynamic idle channel estimating CCA (ClearChannelAssessment) thresholding and interference power, receiving node is when receiving RTS grouping, and physical layer can measure received power and the received signal to noise ratio of RTS grouping in real time, the received power P of therefore RTS grouping
rtswith received signal to noise ratio SINR
realcan read and record from physical layer, the all nodes being positioned at RTS transmission range receive this RTS and divide into groups, and RTS is analyzed, the destination address field (DAF) that each Node extraction RTS comprises in dividing into groups, if destination address does not mate with medium access control MAC (MediaAccessControl) address of this node, then extract the duration Duration field comprised in RTS grouping, and according to IEEE802.11 standard configuration network allocation vector NAV, namely in this Duration duration, virtual carrier sense mechanism indicating channel hurries, this node suspends according to IEEE802.11DCF mechanism to be kept out of the way, if destination address mates with the medium access control MAC Address of this node, then receiving node for the purpose of this node, the received power P that object receiving node record RTS divides into groups
rtswith received signal to noise ratio SINR
real, and proceed to step 4,
Step 4: receiving node calculates dynamic CCA threshold value CCA
thwith interference power P
i, and proceed to step 5, dynamic CCA threshold value CCA
thfor:
CCA
th＝P
rts-SINR
*(1)
Wherein formula (1) Zhong Ge variable unit is dB, wherein SINR
*for the fixing signal-noise ratio threshold value preset, this threshold value and channel fading factor-related, the channel fading factor is larger, and signal-noise ratio threshold value is larger, SINR
*random value between [15,25], suggestion SINR
*the desirable SINR of value
*=20, interference power P
ifor:
P
i＝P
rts-SINR
real(2)
Step 5: the received signal to noise ratio that definition signal to noise ratio Dynamic gene k expects in order to adjustment, k is value between [0,1], and degree β is in order to judge the annoyance level of channel for definition channel disturbance, definition maximum channel annoyance level β
maxin order to determine the maximum channel interference that receiving node allows, RTS received signal to noise ratio P
rtslarger, then maximum channel annoyance level β
maxlarger, and meet relation: β
max=P
rts-SINRth
1, wherein SINRth
1for minimum received signal to noise ratio threshold value, channel disturbance degree β is at [0, β
max] random value, the CCA threshold value CCA that receiving node calculates according to step 4
thwith interference power P
imake the following judgment:
If a) P
i≤ CCA
th, then k=0.5 is set, if P
i> CCA
th, and P
i-CCA
th≤ β, then arrange k=1, and proceed to step 6;
If b) P
i> CCA
th, and P
i-CCA
th> β, receiving node does not reply clear to send CTS (ClearToSend) grouping, proceeds to step 12;
Step 6: the DATA transmission rate of node support is designated as r
1, r
2... r
n, and r
1< r
2< ... < r
n, corresponding received signal to noise ratio threshold value is SINRt
1, hSINRt
2h ... SINRt
nh, and SINRth
1< SINRth
2< ... < SINRth
n, for transmission rate r
i(i=1,2 ... n), only have received signal to noise ratio to be more than or equal to corresponding received signal to noise ratio thresholding SINRth
i(i=1,2 ... n), receiving node could correctly receive transmitted packet with corresponding speed;
Receiving node calculates three variablees, i.e. DATA packet rates, jamming margin and acceptance probability, and first receiving node selects the expectation received signal to noise ratio value received when data DATA (data) divides into groups to be SINR
desired,
SINR
desired＝SINR
*+k*(SINR
real-SINR
*)
Then DATA speed r is determined by the following method:
If SINRth
i≤ SINR
desired< SINRth
i+1, then r=r
i, wherein SINRth
ifor DATA transmission rate r
icorresponding received signal to noise ratio thresholding, SINRth
i+1for DATA transmission rate r
i+1corresponding received signal to noise ratio thresholding, i=1,2 ... n-1; If SINR
desired>=SINRth
n, then r=r
n, wherein SINRth
nfor maximum DATA transmission rate r
ncorresponding received signal to noise ratio thresholding;
Jamming margin P
ccomputational methods be:
P
c＝P
rts/SINR
desired-P
i
The computational methods of acceptance probability p are:
If this receiving node receives the RTS grouping that sending node sends first, then arranging acceptance probability is p
0, p
0random value between [0,1]; If this receiving node is not the RTS grouping receiving sending node transmission first, and the front acceptance probability once receiving the rear setting of RTS grouping is p
lastif the front DATA that once correctly receives divides into groups, then the acceptance probability reducing this is p=p
last-Δ p, if p < 0, then arranges p=0, and once correctly do not receive DATA grouping if front, then the acceptance probability improving this is p=p
last+ Δ p, if p > 1, then arranges p=1, and Δ p is acceptance probability adjustment amount, need preset, Δ p can between (0,1) random value, suggestion Δ p value desirable Δ p=0.1, proceeds to step 7 afterwards;
Step 7: receiving node builds CTS grouping, CTS packet format of the present invention with the addition of 3 fields on IEEE802.11 criteria field basis, comprise DATA packet rates field 3 bit, jamming margin field 10 bit and acceptance probability field 3 bit, receiving node is by DATA speed r, jamming margin P
cbe filled into DATA speed field, jamming margin field and the acceptance probability field in CTS grouping respectively with acceptance probability p, all the other fields of CTS grouping are arranged according to IEEE802.11 standard, proceed to step 8 afterwards;
Step 8: receiving node replys CTS grouping, proceeds to step 9 afterwards;
Step 9: all nodes being positioned at CTS transmission range receive this CTS and divide into groups, and CTS is analyzed, the destination address field (DAF) that each Node extraction CTS comprises in dividing into groups, if medium access control MAC (MediaAccessControl) matching addresses of destination address and this node, then this node is source sending node, the DATA speed field that sending node divides into groups from CTS extracts DATA packet rates r, sends DATA grouping, proceed to step 10 afterwards according to DATA packet rates r; If destination address does not mate with medium access control MAC (MediaAccessControl) address of this node, then the received power P of this nodes records CTS grouping
cts, proceed to step 11 afterwards;
Step 10: sending node wait-receiving mode node reverts back confirms ACK (Acknowledgement) grouping, if receive ACK grouping, then the end of transmission, otherwise with binary exponential backoff mode competitive channel, to retransmit;
Step 11: the jamming margin field that other nodes divide into groups from CTS extracts jamming margin information P
c, acceptance probability field extracts acceptance probability information p, and makes following judgement:
If P
cts≤ P
c, then node produces the random number p between [0,1]
randif, p
rand>=p, then this node does not accept the NAV information in CTS grouping, proceed to step 12, otherwise, the duration Duration field that this Node extraction CTS comprises in dividing into groups, according to IEEE802.11 standard configuration network allocation vector NAV, namely in this Duration duration, virtual carrier sense mechanism indicating channel hurries, and this node suspends according to IEEE802.11DCF mechanism to be kept out of the way;
Step 12: node does not accept the NAV information of receiving node, then virtual carrier sense mechanism indicating channel is idle, if node is positioned at the Physical carrier sense scope of sending node, then Physical carrier sense mechanism indicating channel hurries, and this node suspends according to IEEE802.11DCF mechanism to be kept out of the way; If node is positioned at outside the Physical carrier sense scope of sending node, then Physical carrier sense mechanism indicating channel is idle, and now this node can continue to keep out of the way, and has kept out of the way rear access channel, thus transmit concurrent efforts simultaneously with existing, improve the space reuse degree of network.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510407868.8A CN105101453B (en) | 2015-07-13 | 2015-07-13 | A kind of carrier sensing method based on dynamic idle channel assessment threshold |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510407868.8A CN105101453B (en) | 2015-07-13 | 2015-07-13 | A kind of carrier sensing method based on dynamic idle channel assessment threshold |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105101453A true CN105101453A (en) | 2015-11-25 |
| CN105101453B CN105101453B (en) | 2018-12-18 |
Family
ID=54580693
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510407868.8A Expired - Fee Related CN105101453B (en) | 2015-07-13 | 2015-07-13 | A kind of carrier sensing method based on dynamic idle channel assessment threshold |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105101453B (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105429734A (en) * | 2015-11-30 | 2016-03-23 | 上海电机学院 | Ad hoc multiple access protocol based on flow control technology |
| CN105846924A (en) * | 2016-03-22 | 2016-08-10 | 深圳森格瑞通信有限公司 | Wireless local area network interference suppression method and anti-interference wireless local area network device |
| CN106572499A (en) * | 2016-11-07 | 2017-04-19 | 西北工业大学 | Chanel access method based on decimal backoff |
| CN106937403A (en) * | 2015-12-31 | 2017-07-07 | 华为技术有限公司 | A kind of back-off method and equipment based on space reuse |
| CN107613518A (en) * | 2016-07-11 | 2018-01-19 | 华为技术有限公司 | A kind of network allocation vector value method to set up and device |
| CN107969170A (en) * | 2016-01-11 | 2018-04-27 | 华为技术有限公司 | The methods, devices and systems of wireless communication |
| CN113347736A (en) * | 2021-07-06 | 2021-09-03 | 南京大学 | MIMO-based mobile ad hoc network multipoint communication method |
| CN114006665A (en) * | 2021-11-01 | 2022-02-01 | 杭州联芯通半导体有限公司 | Detection method of idle channel, electronic device and storage medium |
| WO2022095949A1 (en) * | 2020-11-05 | 2022-05-12 | 华为技术有限公司 | Channel monitoring method and related apparatus |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070242621A1 (en) * | 2006-04-13 | 2007-10-18 | Qualcomm Incorporated | Dynamic carrier sensing thresholds |
| CN102685777A (en) * | 2012-04-23 | 2012-09-19 | 西安电子科技大学 | Data concurrent transmission system and method based on jamming margin |
| CN103686843A (en) * | 2013-09-09 | 2014-03-26 | 镇江青思网络科技有限公司 | Congestion control scheme for jointly regulating physical carrier sense range and minimum competition window in VANET |
-
2015
- 2015-07-13 CN CN201510407868.8A patent/CN105101453B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070242621A1 (en) * | 2006-04-13 | 2007-10-18 | Qualcomm Incorporated | Dynamic carrier sensing thresholds |
| CN102685777A (en) * | 2012-04-23 | 2012-09-19 | 西安电子科技大学 | Data concurrent transmission system and method based on jamming margin |
| CN103686843A (en) * | 2013-09-09 | 2014-03-26 | 镇江青思网络科技有限公司 | Congestion control scheme for jointly regulating physical carrier sense range and minimum competition window in VANET |
Non-Patent Citations (3)
| Title |
|---|
| YUEJIE YUAN，ETC: "A Cooperative Channel Reservation MAC Protocol with Adaptive Power Control and Carrier Sensing", 《2012 INTERNATIONAL CONFERENCE ON CONNECTED VEHICLES AND EXPO》 * |
| 尹杰晨等: "一种基于子载波侦听的宽带无线网络接入控制策略", 《电子学报》 * |
| 陈沫等: "无线多跳网络结合功率控制的物理载波侦听分析模型", 《软件学报》 * |
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105429734A (en) * | 2015-11-30 | 2016-03-23 | 上海电机学院 | Ad hoc multiple access protocol based on flow control technology |
| CN106937403A (en) * | 2015-12-31 | 2017-07-07 | 华为技术有限公司 | A kind of back-off method and equipment based on space reuse |
| CN106937403B (en) * | 2015-12-31 | 2020-01-31 | 华为技术有限公司 | backoff method and device based on spatial reuse |
| US12028885B2 (en) | 2016-01-11 | 2024-07-02 | Huawei Technologies Co., Ltd. | Wireless communication method and apparatus |
| US11452109B2 (en) | 2016-01-11 | 2022-09-20 | Huawei Technologies Co., Ltd. | Wireless communication method and apparatus |
| CN107969170A (en) * | 2016-01-11 | 2018-04-27 | 华为技术有限公司 | The methods, devices and systems of wireless communication |
| US10798717B2 (en) | 2016-01-11 | 2020-10-06 | Huawei Technologies Co., Ltd. | Wireless communication method and apparatus |
| CN105846924A (en) * | 2016-03-22 | 2016-08-10 | 深圳森格瑞通信有限公司 | Wireless local area network interference suppression method and anti-interference wireless local area network device |
| CN107613518B (en) * | 2016-07-11 | 2020-06-26 | 华为技术有限公司 | Network allocation vector value setting method and device |
| CN107613518A (en) * | 2016-07-11 | 2018-01-19 | 华为技术有限公司 | A kind of network allocation vector value method to set up and device |
| WO2018082133A1 (en) * | 2016-11-07 | 2018-05-11 | 西北工业大学 | Decimal backoff-based channel access method |
| CN106572499A (en) * | 2016-11-07 | 2017-04-19 | 西北工业大学 | Chanel access method based on decimal backoff |
| WO2022095949A1 (en) * | 2020-11-05 | 2022-05-12 | 华为技术有限公司 | Channel monitoring method and related apparatus |
| TWI834516B (en) * | 2020-11-05 | 2024-03-01 | 大陸商華為技術有限公司 | A channel listening method and a related apparatus |
| CN113347736A (en) * | 2021-07-06 | 2021-09-03 | 南京大学 | MIMO-based mobile ad hoc network multipoint communication method |
| CN113347736B (en) * | 2021-07-06 | 2023-01-06 | 南京大学 | MIMO-based mobile ad hoc network multipoint communication method |
| CN114006665A (en) * | 2021-11-01 | 2022-02-01 | 杭州联芯通半导体有限公司 | Detection method of idle channel, electronic device and storage medium |
| CN114006665B (en) * | 2021-11-01 | 2023-10-27 | 杭州联芯通半导体有限公司 | Idle channel detection method, electronic equipment and storage medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105101453B (en) | 2018-12-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105101453A (en) | Carrier sensing method based on dynamic idle channel assessment threshold | |
| EP3206313B1 (en) | Method and system for detecting idle channel in wireless communication system | |
| CN101127661B (en) | A wireless competition access control method based on congestion degree possibility P | |
| EP1386419B1 (en) | Instantaneous joint transmit power control and link adaptation for rts/cts based channel access | |
| US8125921B2 (en) | Mobile station communicating with a base station via a separate uplink when the parameters of channel quality fall below the predefined thresholds | |
| WO2013131468A1 (en) | System and method for sectorized transmission in a wireless network | |
| US9693363B2 (en) | Method and apparatus for controlling clear channel assessment threshold | |
| EP3236691B1 (en) | System and method for low power transmission | |
| CN105230106B (en) | Information sending method and device | |
| CN110972105B (en) | Communication method, communication device and user equipment | |
| CN104010378A (en) | Wireless local area network access method, access point and wireless local area network system | |
| CN100574318C (en) | A kind of method of WLAN (wireless local area network) multi-velocity self-adapting transmission | |
| US11197319B1 (en) | Enhanced spatial reuse of radio spectrum in WLAN operation | |
| CN103856303A (en) | Method for dynamically setting minimum node contention window value according to retransmission frequency | |
| CN114513283B (en) | Data transmission method, device, equipment and storage medium based on spatial multiplexing | |
| Kosek-Szott et al. | A new busy signal-based MAC protocol supporting QoS for ad-hoc networks with hidden nodes | |
| Gao et al. | An adaptive contention window scheme for 802.11 ah WLANs | |
| WO2022077362A1 (en) | Method and device for random access in wireless communication system | |
| CN104255072A (en) | Power control method and device | |
| CN102098794A (en) | Method and apparatus for processing random access collision | |
| CN107041006A (en) | The method and apparatus for transmitting data | |
| CN106817193B (en) | Access point communication method and access point | |
| Huang et al. | An adaptive contention window algorithm to hybrid OFDMA/CSMA mechanism in WLANs | |
| López Aguilera et al. | Evaluating wireless LAN access methods in presence of transmission errors | |
| Botezatu et al. | Adaptive Power Control in 802.11 Wireless Mesh Networks |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20181218 Termination date: 20190713 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |