1. Deployment Analysis in Underwater Acoustic Wireless Sensor Networks Dario Pompili, Tommaso Melodia, lan F. Akyildiz ACM WUWNet’06 2008. 12. 9. Ahn Jung-Sang

2. Content IntroductionIntroduction Communication ArchitecturesCommunication Architectures Deployment Strategies in 2DDeployment Strategies in 2D Deployment Strategies in 3DDeployment Strategies in 3D ConclusionConclusion 2

3. Introduction Underwater Acoustic Sensor Network (UW-ASN)Underwater Acoustic Sensor Network (UW-ASN) –Challenges Harsh environment Limited bandwidth High & variable propagation delay, error rates Etc. This PaperThis Paper –Propose a mathematical & hydrodynamics model in 2D Considering depth, current, and so on. Determine the minimum number of sensors Provide guidelines on how to choose the optimal deployment –And extend this 3D briefly 3

4. Communication Architectures 2D Architecture2D Architecture 4

5. Communication Architectures 3D Architecture3D Architecture 5

6. Deployment in 2D Triangular-grid Coverage PropertiesTriangular-grid Coverage Properties –Sensors with same sensing range r –Optimal deployment to cover a 2D area with minimum number of sensors 6

7. Deployment in 2D Triangular-grid Coverage PropertiesTriangular-grid Coverage Properties –Sensing coverage η –We can estimate d/r when we set η. In this paper, η=0.95, and corresponding d/r = 1.95 7 Overlap Non-overlap

8. Deployment in 2D Triangular-grid Coverage PropertiesTriangular-grid Coverage Properties 8 Coverage=0.95 Ratio of sensor dis tance and sensing range=d/r=1.95

9. Deployment in 2D Triangular-grid Coverage PropertiesTriangular-grid Coverage Properties 9 100 x 100 m^2300 x 200 m^2

10. Deployment in 2D Trajectory of a Sinking ObjectTrajectory of a Sinking Object 10

11. Deployment in 2D Trajectory of a Sinking ObjectTrajectory of a Sinking Object –Assumptions in this paper: No vertical movement of ocean water The considered area is neither an upwelling nor a downwelling The velocity of the ocean current depends on depth –H: # of different ocean current layers –Current in each layer has a fixed module and angular deviation (with known statistics) –Thermohaline Circulation (ocean’s conveyor belt) 11

12. Deployment in 2D Trajectory of a Sinking ObjectTrajectory of a Sinking Object –Kind of Hydrodynamics 12

13. Deployment in 2D Trajectory of a Sinking ObjectTrajectory of a Sinking Object 13

14. Deployment in 2D Communication Properties of 2D UW-ASNsCommunication Properties of 2D UW-ASNs –Every sensed data should pass gate-way –Sensor & gate-way have different weights Gate-way is heavier than sensor 14

15. Deployment in 2D Deployment Surface Area: Side MarginsDeployment Surface Area: Side Margins 15

16. Deployment in 3D 3 Strategies3 Strategies –3D-random The simplest strategy. Random deploy, random depth. –Bottom-random Random deploy. Surface station calculates the depth for each sensor. –Bottom-gird Assisted by one or multiple AUV Grid deploy. Assigned a desired depth by the AUV 16

17. Deployment in 3D 3 Strategies3 Strategies 17

18. Conclusion Deployment strategies for 2D and 3D architectures for UW-ASNsDeployment strategies for 2D and 3D architectures for UW-ASNs Deployment analysis in order to:Deployment analysis in order to: –Determine the minimum number of sensors –Provide guidelines on how to choose the deployment –Determine the minimum number of uw-gateways, given some desired communication properties of clusters 18