A Coverage-Preserving Node Scheduling Scheme for Large Wireless Sensor Networks Di Tian, Nicolas D. Georganas First ACM international workshop on Wireless sensor networks and applications (WSNA),2002,pp Speaker : 陳希維

Outline  Introduction  Node self-scheduling algorithm  Performance evaluation and simulation  Conclusions

Introduction  Increasing system lifetime, by turning off some redundant nodes.  Guarantees that the original sensing coverage is maintained.  Extension of the LEACH protocol  Goal: Minimizing energy consumption and Maximizing the system lifetime

Node self-scheduling algorithm  Coverage-based off- duty eligibility rule  Sponsored sector:(b) 陰 影部分 :

Node self-scheduling algorithm  Node Scheduling Scheme Based On Eligibility Rule Two setps: 1. Neighbor Information Obtaining Step. 利用 position AdvertisementMessage(PAM )

Node self-scheduling algorithm  2. Back-off Based Self-scheduling Step Broadcast a Status Advertisement Message (SAM) to announce its status.

Node self-scheduling algorithm  流程圖

Performance evaluation and simulation  Comparison with probing-based off-duty eligibility rule.

Performance evaluation and simulation  On-duty node number vs. node density

Performance evaluation and simulation  Sensing Coverage vs. node density

Performance evaluation and simulation

Conclusions  reduce energy consumption,increase system lifetime coverage-based off-duty eligibility rule is better than the LEACH protocol.