A wireless sensor network (WSN) enables hundreds or thousands of sensor nodes -with communication, sensing, and processing units-organized in an ad-hoc manner in order to achieve a predefined goal, like environmental monitoring, battlefield surveillance, etc. Due to the limited and practically irreplaceable energy resources of sensor nodes, prolonging the network lifetime becomes the most critical issue while dealing with WSN. When a sink (data collection point) is statically placed, the sensor nodes that can directly communicate with it tend to deplete their energy faster than other nodes since they not only transmit their packets but also relay the other nodes\' packets to the base station. Mobile sink can significantly improve the network lifetime by moving itself to different locations in the deployment area and change its neighbors periodically. In this work we give the current state of the art for sink mobility issue for the sake of increasing the lifetime of sensor networks, mention about the constraints that are defined in the theoretical modeling such as linear programming, and present an uncontrolled mobility scheme that does not have any restriction for the number of anchor points. Early results show that the proposed scheme has three times longer network lifetime than the static sink approach.

DATE: 16 April, 2007, Monday@ 15:40
PLACE: EA 409