An approximate optimal coverage set algorithm in wireless sensor networks

Sensing coverage is a fundamental issue in wireless sensor networks (WSNs). Due to power constraints of sensors, it may not be possible, to provide full coverage in WSNs. Under a certain coverage requirement, the node deployment strategy becomes a challenging issue in randomly deployed networks. In this paper, we first propose a coverage probability model (CPM), which reflects the relations among the coverage rate, the number of deployed sensor nodes, the sensing range of sensor nodes, and the network size. This model can be used to calculate the number of sensor nodes that need to be deployed for maintaining a certain coverage rate. Then, an approximate optimal cover set (AOCS) is proposed to find a largest cover set. The simulation results have shown that the error rate of node deployment is less than 5%. The proposed model and algorithm are very useful in estimating the coverage capacity in a randomly deployed sensor network.