Continuous Residual Energy Monitoring in Wireless Sensor Networks

A crucial issue in the management of sensor networks is the continuous monitoring of residual energy level of the sensors in the network. In this paper, we propose a hierarchical approach to construct a continuous energy map of a sensor network. Our method consists of a topology discovery and clustering phase, followed by an aggregation phase when energy information collected are abstracted and merged into energy contours in which nodes with similar energy level are grouped into the same region. The monitoring tree is restructured periodically to distribute energy cost among all nodes fairly, which increases the lifetime of the sensor network. Simulation results indicate that our method is able to generate accurate energy maps with low energy cost.