Date Added: Mar 2010
A crucial issue in the management of sensor networks is the continuous monitoring of residual energy level of the sensors in the network. With the large number of sensors in a typical network, the energy monitoring process can itself be very energy intensive. In this paper, the authors propose a hierarchical approach to construct a continuous energy map of a sensor network. The method consists of a topology discovery and clustering phase, followed by an aggregation phase when energy information collected and merged into energy contours in which nodes with similar energy level are grouped into the same region.