barrier coverage with mobile sensors
DESCRIPTION
Barrier Coverage with Mobile Sensors. Changxiang ShenWeifang Cheng Xiangke LiaoShaoliang Peng. National University of Defense Technology. I-SPAN 2008. Proceedings of the I nternational S ymposium on P arallel Architectures, A lgorithms and N etworks. Outline. Introduction - PowerPoint PPT PresentationTRANSCRIPT
Barrier Coverage with Mobile Sensors
Changxiang Shen Weifang ChengXiangke Liao Shaoliang Peng
National University of Defense Technology
Proceedings of the International Symposium on Parallel Architectures, Algorithms and Networks
I-SPAN 2008
OutlineOutline
IntroductionIntroduction Problem FormulationProblem Formulation CBarrier algorithmCBarrier algorithm DBarrier algorithmDBarrier algorithm Performance EvaluationPerformance Evaluation ConclusionConclusion
IntroductionIntroduction
In the wireless sensor network (WSN) In the wireless sensor network (WSN) sensors monitor the field for some sensors monitor the field for some applicationapplication to monitor the entire environmentto monitor the entire environment
Full coverageFull coverage the boundary guard or the movement the boundary guard or the movement
detectiondetection Barrier coverageBarrier coverage
IntroductionIntroduction
An example An example
randomly deployed sensors for barrier coveragerandomly deployed sensors for barrier coverage
"Reliable Density Estimates for Achieving Coverage and Connectivity in Thin Strips of Finite Length" P. Balister, B. Bollobas, A. Sarkar, S. Kumar. in Proceedings ofACM MobiCom. 2007.
IntroductionIntroduction
When sensors are deployedWhen sensors are deployed Randomly Randomly
much more sensors are required than much more sensors are required than deterministically deployeddeterministically deployed
DeterministicallyDeterministically Environment limitationEnvironment limitation Cost a lot of timeCost a lot of time
This paper study barrier coverage This paper study barrier coverage with mobile sensorswith mobile sensors Relocated after random deploymentRelocated after random deployment Utilize much fewer mobile sensorsUtilize much fewer mobile sensors
Problem FormulationProblem Formulation
AssumptionAssumption N mobile sensorN mobile sensor
S={S={ss11,s,s22,…,s,…,sNN}} Each sensor sEach sensor sii has initial coordinates has initial coordinates ((xxii,y,yii)) Sensing range : Sensing range : RR
Problem FormulationProblem Formulation
The interesting area : W x LThe interesting area : W x L
L
W
(0,0)
(0,W) (L,W)
(L,0)
Minimum number :Minimum number : RL 2/
Maximum numberMaximum number
R
RL
2
22
Problem FormulationProblem Formulation
Given the randomly deployed mobile Given the randomly deployed mobile sensorssensors To provide required barrier coverageTo provide required barrier coverage
(It is not hard)(It is not hard) The sensor moving is waste energyThe sensor moving is waste energy
The paper propose an relocation The paper propose an relocation algorithmalgorithm Save energy consumptionSave energy consumption
Problem FormulationProblem Formulation22 )''()''(),( jiji yyxxjid
N
iiiii yyxx
1
22 )'()'(min
NiRjidxxj ij ...1 ))2),(()''((
NiRjidxxj ji ...1 ))2),(()''((
)'0( Rxj j
)'( LxRLj j
Goal :
There is a left neighbor
There is a right neighbor
There is a sensor overlapping the left boundary
There is a sensor overlapping the right boundary
Centralize Barrier Algorithm(CBarrier) To assume that To assume that
the relocated sensors are aligned into a straight lithe relocated sensors are aligned into a straight line y=ax+bne y=ax+b
yyii’=ax’=axii’+b’+b Order the xOrder the xii by the sort of by the sort of
xx11≤x≤x2 2 ≤≤ xx3 3 ≤≤ … ≤ x… ≤ xNN
xx11’=R , x’=R , xNN’=L-R’=L-R the xthe xii’=R+(i-1)[(L-R)-R]/(N-1)’=R+(i-1)[(L-R)-R]/(N-1)
R
WLN
2
22
Centralize Barrier Algorithm(CBarrier)
)]1/()2[(*)1(
)''(*)1(
)'')(1(
))'()'(()''(
)''()''()1,(
2
12
21
2
21
21
21
21
NRLa
xxa
xxa
baxbaxxx
yyxxiid
ii
ii
iiii
iiii
Centralize Barrier Algorithm(CBarrier)
L
W
(0,0)
(0,W) (L,W)
(L,0)LWa /
Riid 2)1,( Riid 2),1(
N
iiiii yyxxbaF
1
22 ))'()'((),(
Distributed Barrier AlgorithmDistributed Barrier Algorithm(DBarrier)(DBarrier) The virtual forceThe virtual force
FR : repulsive forceFR : repulsive force FA : attractive forceFA : attractive force
L
W
(0,0)
(0,W) (L,W)
(L,0)
Performance EvaluationPerformance Evaluation
MATLABMATLAB Sensing range Sensing range R R : 4m: 4m Communication range Communication range RRc c : 10m: 10m Field size W x L : 15m x 60mField size W x L : 15m x 60m The number of sensor :15The number of sensor :15 Move unit :0.1m~0.8mMove unit :0.1m~0.8m MAX_STEP = 100MAX_STEP = 100
ConclusionConclusion
This paper discusses the MEBC problem This paper discusses the MEBC problem and propose two algorithmand propose two algorithm The CBarrier algorithmThe CBarrier algorithm
To compute the relocated position with knowing To compute the relocated position with knowing the initial positionthe initial position
The DBarrier algorithmThe DBarrier algorithm Sensors adjust the position according the total vSensors adjust the position according the total v
irtual forceirtual force