Coverage Optimization in Wireless Sensor Networks Using Gravitational Search Algorithm

Wireless sensor networks include low-weight low cost nodes equipped with limited processing and energy sources. Sensor nodes monitor their surroundings and send sensed events to the sink node through shortest path. One of the major challenges in these networks is to keep nodes connected to each other while the target area is covered effectively. These two parameters are referred as main parameters of quality of service (QoS). In this paper, optimal area coverage is carried out using the Gravitational Search Algorithm. In the proposed algorithm, the agents or masses are equivalent to sensor nodes. The nodes are influenced by distance, Newton gravity law and the laws of motion. A group of nodes can be considered as a cluster. The proposed algorithm is compared with previous methods in terms of network life time, remaining energy and network power. Simulation results show that the proposed method reduces energy consumption by optimizing the number of nodes in the area with maximal coverage, and increases the lifetime and effectiveness of the network.