A distributed energy-efficient approach for hole repair in wireless sensor networks

Wireless sensor networks consisting of numerous nodes function in such a manner that each node that collects data from its physical environment, conveys them to the base station for rigorous analysis. Maintaining the functional coverage, energy consumption and the lifetime are among the most challenging factors for WSN. The aim of this paper is to provide an effective coverage with a simultaneous reduction in energy consumption using mobile nodes and evolutionary firefly algorithm. The methodology involves dividing network area into equal cells though smaller size, in order to facilitate the estimation of the physical coverage. In areas with desirable and sufficient coverage, the operational scheduling of nodes is set in such a manner to activate some sensors to ensure necessary coverage and deactivate others. This, to a great extent, decreases the demand for energy. Under the circumstances where the cells are deprived of appropriate or sufficient coverage, mobile nodes are used to improve the coverage. This is achieved by using firefly algorithm to determine the optimum deployment of mobile nodes to perform the job. Results of simulation show that the proposed method has greater superiority over its comparative techniques, particularly on aspects such as the rate of network field area, energy consumption and network lifetime to mention a few.