Energy-efficient Coverage Algorithm In Wireless Sensor Networks

One of the most fundamental problems in wireless sensor networks is the coverage problem, which mainly solve these problems how to improve the network quality monitoring and prolong the network lifetime.Now most of algorithms on coverage problems need geographic information with the help of GPS positioning system, which is not conducive to build a low-cost sensor networks. Further, because most wireless sensor networks(WSNs) operate in three-dimensions(3D), coverage algorithms considered in two-dimensions(2D) are not practical. For this, the paper focuses on the coverage problem in wireless sensor networks. The main works are as follows:First of all, the existing coverage algorithms are described briefly, and the strengths and weaknesses are analyzed. The SGA is the free-location coverage algorithm in two-dimensions(2D), which has advantage in coverage percentage and redundant node rate, but is bad in energy consumption. In this pater, we will spread the SGA in three-dimensions(3D), and propose a novel energy-efficient coverage algorithm in Wireless Sensor Networks——SSG algorithm in three-dimensions, which is independent of nodes'location information, solve the imbalance of energy consumption, prove the feasibility of the algorithm in theory, be verified by using the example, and examine the quality of service by simulations.Secondly, to resolve another question in the SSG algorithm, that is, the coverage rate of networks decreases quickly with Rsg (the radii that sensor nodes broadcast the message) increasing. Based on random sleep scheduling ideas, in this paper, we propose ISSG algorithm that make use of probability to make a node active, guarantee the coverage percentage by adjusting the value of probability. Simulations show that the algorithm can guarantee a high coverage rate.