kais t sensor deployment based on virtual forces reference: yi zou and krishnendu chakarabarty,...
DESCRIPTION
3/18 Sensor Deployment Based on VFA Introduction The effectiveness of distributed sensor networks (DSN) Depends on the sensor deployment Coverage, communication cost, resource management Random deployment Practical for military applications Not always lead to effective coverage New sensor placement strategy Maximize the coverage for a given number of sensors Virtual Force Algorithm (VFA) as a sensor deployment of sensors Enhance the coverage after initial random placement of sensorsTRANSCRIPT
KAIST
Sensor Deployment Based on Virtual Forces
Reference: Yi Zou and Krishnendu Chakarabarty, “Sensor Deployment and Target Localization Based on Virtual Forces”, Department of Electrical and Computer Engineering, Duke University, IEEE INFOCOM 2003
2007. 10. 4Hong Jae-Young
22/18/18Sensor Deployment Based on VFA
Contents
Introduction
Related Prior Work
Virtual Force Algorithm
Simulation Results
Conclusion
33/18/18Sensor Deployment Based on VFA
Introduction
The effectiveness of distributed sensor networks (DSN)Depends on the sensor deployment
Coverage, communication cost, resource management
Random deployment
Practical for military applications
Not always lead to effective coverage
New sensor placement strategyMaximize the coverage for a given number of sensors
Virtual Force Algorithm (VFA) as a sensor deployment of sensors
Enhance the coverage after initial random placement of sensors
44/18/18Sensor Deployment Based on VFA
Related Prior Work
A variety of work for Sensor deployment problemsA bidding Protocol for Deploying Mobile Sensor
Sensor Deployment and Sensor Planning for Elusive Targets A priori knowledge about possible target
No information about potential target
Mobile Sensor Network Deployment Using Potential FieldEach robot is a sensor node
Expensive and a large amount of computation
Coverage problems in wireless ad-hoc sensor networksSelf-localization
Sensor nodes are should be highly mobile and move frequently
Radar and sonar coverage
55/18/18Sensor Deployment Based on VFA
Virtual Force Algorithm : VFA (1/7)
Basic assumptionsAfter the initial random deployment, all sensor nodes are able to
communicate with the cluster head
The cluster head is responsible for executing the VFA and managing the
one-time movement of sensors to the desired locations
Basic idea of VFAEach sensor behaves as a “Source of force” for all other sensors
Positive (Attractive) vs. Negative (Repulsive)
Globally uniform sensor placement
66/18/18Sensor Deployment Based on VFA
Virtual Force Algorithm : VFA (2/7)
Sensor Detection ModelsConsider an n by m sensor field grid
K sensor deployed in the random deployment stage
Each sensor has a detection range r
Let si deployed at point (xi , yi), any point P at (x , y)
22 y)(yx)(x,P)d(s ii i
Binary Sensor Detection Model
Probabilistic Sensor Detection Model
r
n
m
rr
P (x , y)
77/18/18Sensor Deployment Based on VFA
Virtual Force Algorithm : VFA (3/7)
Virtual ForcesNotation
Let the total force action on sensor si be denoted by
Let the force exerted on si by another sensor sj be denoted by
Let total repulsive force on si by
Let total attractive force on si by
Virtual force calculation in the VFATotal force on si,
iF
ijF
iAFiRF
iF
k
ijjiAiRiji FFFF
,1
88/18/18Sensor Deployment Based on VFA
Virtual Force Algorithm : VFA (4/7)
An example of virtual forces with four sensors
1413121 FFFF
If we assume that d12>dth , d13<dth , d14=dth ,s2 exerts an attractive force on s1,s3 exerts a repulsive force on s1,s4 exerts no force on s1
If re=0 then Binary sensor detection modelMake dij as close to 2r as possible
99/18/18Sensor Deployment Based on VFA
Virtual Force Algorithm : VFA (5/7)
Non-overlapped and overlapped sensor coverage areas
Non-overlapped area Overlapped area
Non-overlapped areaMinimize “wasted overlap”
A few grid points are not covered by any sensor
Overlapped areaMore sensors for grid coverage
Therefore, adopt the Non-overlapped areaTotal Coverage area is 2rk
1010/18/18Sensor Deployment Based on VFA
Virtual Force Algorithm : VFA (6/7)
If re>0, re is not negligible
Probabilistic Sensor Detection Model
Grid points are not covered with the same probability
Necessary overlap sensor detection areas
))(1))((1(1),( ,,, jyxiyxjiyx scscssc
ovi Ss
iyxovyx scsc ))(1(1)( ,,
1111/18/18Sensor Deployment Based on VFA
Virtual Force Algorithm : VFA (7/7)
Coverage Evaluation
Virtual Forces among sensors
Move sensor virtually
1212/18/18Sensor Deployment Based on VFA
Simulation Results (1/5)
ParametersA total of 20 sensors
Random placement
Detection radius as 5 unit (r=5)
Large detection error as 3 unit (re=3)
50 by 50 sensor field
Pentium III 1.0GHz PC using MATLAB
1313/18/18Sensor Deployment Based on VFA
Simulation Results (2/5)
Binary Sensor Detection Model
1414/18/18Sensor Deployment Based on VFA
Simulation Results (3/5)
Binary Sensor Detection Model
1515/18/18Sensor Deployment Based on VFA
Simulation Results (4/5)
Probabilistic sensor detection model
1616/18/18Sensor Deployment Based on VFA
Simulation Results (5/5)
1717/18/18Sensor Deployment Based on VFA
Conclusion
Virtual Force Algorithm Practical approach for sensor deployment
Advantages
Negligible computation timeSmall amount of computation
One time repositioning of the sensorsLow-cost
1818/18/18Sensor Deployment Based on VFA
Questions & Comments
Any Questions?Comments?