Redundant nodes elimination in wireless sensor networks

In the real application situations, the wireless sensor networks (WSNs) usually consist of a large number of sensor nodes with limited energy to monitor the environment. The energy efficiency is one of the most important challenges for WSNs in order to extend the network lifetime. There are several widely-used methods to achieve this goal, such as data fusion at coordination sensor nodes, and turning off redundant nodes, etc. The existing methods of redundant nodes elimination are analyzed, and their disadvantages are discussed. Then a new method of redundant node elimination based on the coverage probability is proposed to maximize the network lifetime for the heterogeneous WSNs. Combining with EECRS protocol, an energy efficient protocol based on redundant nodes elimination is proposed. Using random sensors deployment with different sensing radii, it is shown that the sensing coverage quality after using proposed redundant nodes determination method can be guaranteed to 99.9% with more than 8 neighbor nodes for each sensor node, and proposed method has less on-duty nodes compared with other methods. And that can reduce the energy consumption of network. Compared with perimeter coverage protocol and CCP protocol, proposed protocol can extend the network lifetime.