Solving Target Coverage Problem in Wireless Sensor Networks Using Iterative Heuristic Algorithms

Abstract

Wireless Sensor Networks have proved to be very useful in monitoring environmental conditions of remote or inhospitable areas. One of the major diculty which a designer faces in devising such wireless sensor networks is the limited energy and computational resources available to sensor nodes of the networks. Thus, any application developed at any level of hierarchy must be designed keeping in mind its constraints. The rst work in establishing a sensor network is the deployment of sensor nodes .one solution in case of deployment of sensor nodes in an inhospitable area in which ground access is prohibited is to drop the sensor nodes from aircraft. Since the exact positioning of the sensor nodes on the ground cannot be guaranteed , one solution is to deploy a large number of nodes. Therefore, the number of nodes that are deployed ,with an aim to cover the area completely, is often higher than the required. Activating only those nodes that are necessary at any particular moment rather than all the sensor nodes can save energy. Hence, we divide the sensor nodes into sets such that each set is capable of monitoring all targets and activate those sets one after another. So the overall all lifetime of WSNs will be the sum of the lifetime of cover sets.This process will e ectively lead to increment in the overall lifetime of WSN. This work aims to maximize the lifetime of wireless sensor networks by grouping the sensor nodes into sets and activating the sets successively.By lifetime is meant the to- tal time for which the sensor nodes can monitor the whole target area or all the target objects. Two di erent cases have been dealt with- one when the transmission and recep- tion range of sensors can be adjusted and the other in which the range of transmission and reception is xed.Three di erent algorithmic paradigms are used- Greedy heuristic ,Genetic Algorithm and Particle Swarm Optimization