Extending Sensor Networks Lifetime Through Energy Efficient Organization

In most applications involving wireless sensor networks, each sensor collects data in the surrounding area, and sends to a central node for processing. To extend network lifetime in such cases, the sensors could be partitioned into groups which are successively scheduled to be active for sensing and delivering data. Each group covers (almost) the entire area, and only one group is active at a given time. These groups of sensors are known as disjoint dominating sets in network and graph theory where it has been shown that the problem of computing the maximum number of disjoint dominating sets in graphs is NP-complete [6]. In this paper, we strengthen this result [3] by showing that this problem remains NP-complete for planar unit disk graphs. We introduce several heuristics for the disjoint dominating sets problem and discuss their performance through some simulation results.