Coverage and Lifetime Optimization in Heterogeneous Energy Wireless Sensor Networks

One of the fundamental challenges in Wireless Sensor Networks (WSNs) is the coverage preservation and the extension of the network lifetime continuously and effectively when monitoring a certain area (or region) of interest. In this paper, a coverage optimization protocol to improve the lifetime in heterogeneous energy wireless sensor networks is proposed. The area of interest is first divided into subregions using a divide-andconquer method and then the scheduling of sensor node activity is planned for each subregion. The proposed scheduling considers rounds during which a small number of nodes, remaining active for sensing, is selected to ensure coverage. Each round consists in four phases: (i) Information Exchange, (ii) Leader Election, (iii) Decision, and (iv) Sensing. The decision process is carried out by a leader node, which solves an integer program. Simulation results show that the proposed approach can prolong the network lifetime and improve the coverage performance. Keywords-Wireless Sensor Networks; Area Coverage; Network Lifetime; Optimization; Scheduling.