Greedy approximation algorithm of patching hole in wireless sensor networks

In Wireless sensor network, error of node, energy depletion and other factors will lead to the appearance of hole, then will cause network failures, The existing hole patching algorithm need mobile sensor node to patching the hole, due to the cost of a larger mobile node. This paper presents approximate greedy algorithm which only need to activate some inactive nodes to patching the hole. The strategy detecting hole firstly, analysis feature of hole. According to the characteristics of hole, using a greedy algorithm select the appropriate nodes from an inactive set of nodes to patching the hole, proposes two principles for patching hole. (1) A patching node should cover at least one a hole arc intersection and firstly choose inactive node which cover up the most hole´s arc intersection (2)The coverage hole should not be partitioned by the patching node. Finally through the simulation experiments demonstrate that the proposed strategy is effective, and based on the comparison of the experimental results, analysis the performance of the proposed scheme. Using the proposed strategy can realize hole completely patching, and enhance the patching node coverage ability and utilization.