Chinh T. Vu , Yingshu Li

Computer Science Department Georgia State University

IEEE percom 2009

Delaunay-triangulation based complete coverage inwireless sensor networks

OutlineIntroduction Protocol Simulation Conclusion

Introduction The coverage problems for sensor networks can be categorized into three broad

types Barrier Coverage Target Coverage Area Coverage

AA

Introduction The coverage problems for sensor networks can be categorized into three broad

types Barrier Coverage Target Coverage Area Coverage AA

Target point

Introduction The coverage problems for sensor networks can be categorized into three broad

types Barrier Coverage Target Coverage Area Coverage

AA

Introduction Equilateral triangulation with each edge as has the minimal redundant coverage3 sR

AA

Introduction Random sensor deployment and variable sensing radii

AA

Motivation Overlap Uncovered hole

A B

E

D

C

maxr

A B

E

D

C

maxr

Goal The monitored area can be completely covered.Minimize the energy consumption and extend the lifetime of

networks.

IDT AlgorithmStep 1. Build the local Delaunay triangulationStep 2. Determine weighted centroid of Delaunay

triangulationStep 3. Sensors at border increase sensing ranges

Step 1. Delaunay Triangulation (DT)

Empty Circle Property Nearest

P1

P2

P4P3

P1

P2

P4P3

Step 1. Delaunay Triangulation (DT)

Empty Circle Property Nearest

A B

ED

C

A B

E

D

C

maxr

Step 1.

P1

P4

P8P5

P2

P3

P7

P6

P9

Step 1.

P1

P4

P8P5

P2

P3

P7

P6

P9

Delaunay triangulation

Step 1.

P1

P4

P8P5

P2

P3

P7

P6

P9

Step 2. E(s) : sensor s’s current residual energy

Sx : x coordinate

Sy : y coordinate

(1.5 , 1.6)

(2 , 1)(1 , 1)

0.5 1.5 0.5 1 0.5 21.5

0.5 0.5 0.5xm

0.5 1.6 0.5 1 0.5 11.2

0.5 0.5 0.5ym

A

B C

ID E(s)

A 0.5

B 0.5

C 0.5

Step 2. E(s) : sensor s’s current residual energy

Sx : x coordinate

Sy : y coordinate

(1.5 , 1.6)

(2 , 1)(1 , 1)

0.5 1.5 0.5 1 1 21.625

0.5 0.5 1xm

0.5 1.6 0.5 1 1 11.15

0.5 0.5 1ym

A

B C

ID E(s)

A 0.5

B 0.5

C 1

Step 2. E(s) : sensor s’s current residual energy

Sx : x coordinate

Sy : y coordinate

(1.5 , 1.6)

(2 , 1)(1 , 1)

0.5 1.5 0.5 1 0 21.25

0.5 0.5 0xm

0.5 1.6 0.5 1 0 11.3

0.5 0.5 0ym

A

B C

ID E(s)

A 0.5

B 0.5

C 0

Problem

A

B

C

boundary

Step 1.

A

B

C

D

E

G

F

Step 1.

A

B

C

D

E

G

F

Step 1.

A

B

C

D

E

G

F

Step 2.

A

B

C

D

E

G

F

Step 2.

A

B

C

D

E

G

F

Step 2.

A

B

C

D

E

G

F

Step 3.

A

B

C

D

E

G

F

Step 3. Define priority of a node as <Es, ID >

A

B

C

D

E

G

F E has the highest priority & NOT completely perimeter- covered

G has the highest priority & NOT completely perimeter- covered

Simulation

Parameter Value

Network size 800m X 400m

Number of sensors 100 ~ 500

Energy range 100 ~ 120 mJoules

Maximum sensing range 100m

Simulation

Simulation

Simulation

Conclusion They deal with the area coverage problem with variable sensing

radii variable sensing radii in WSN Using variable sensing radii variable sensing radii in WSN by improving the

energy balancing The monitored area can be completely covered

Thank you~