An Energy Efficiency Node Scheduling Model for Spatial-Temporal Coverage Optimization in 3D Directional Sensor Networks

Low-power green communication has become the utmost important and promising research topic for energy efficiency communications. In this paper, we investigated the energy efficiency green communication in 3-D directional sensor networks. Coverage and schedule are two fundamental research issues for energy efficiency in wireless sensor networks. In network lifetime sensitive scenarios, how to consider the network lifetime as the constraint to trade coverage for network lifetime has not been well investigated. Based on the 3-D sensing model of directional sensors, we address this problem of maximizing the spatial-temporal coverage by scheduling sensors' activity after they have been deployed. First, two elementary region generation approaches, grid-based algorithm, and position-based algorithm are proposed. Then, a spatial-temporal coverage optimization scheduling (STCOS) algorithm is designed to obtain the whole network coverage maximized. Finally, a set of simulation experiments are put forward to evaluate the performance of the proposed elementary regions generation schemes and STCOS algorithms. Experimental results show that compared with the grid-based elementary region generation scheme, the position-based scheme significantly reduces the algorithmic complexity and is time consuming while generating elementary regions in network. Further simulation results show that the proposed STCOS scheme effectively enhances the performance of spatial-temporal coverage optimization.