A Geography-Based Void-Bypassing Routing Protocol for Wireless Sensor Network

Geographic routing protocol (GRP) allows sensor node to select path solely depending on the position information of its neighbor nodes. However, the irregular distribution of sensor node in wireless sensor networks (WSN) gives rise to the problem that GRP using the greedy algorithm may suffer the problem of local extrema. Due to the routing voids, it tends to result in the failure of data transmission. To overcome this drawback and improve the control packet overhead and transmission delay of routing void, based on virtual coordinate mapping, this paper proposes an efficient void-bypassing routing protocol (EVRP). Through mapping the coordinates on a virtual circle for edge nodes, EVRP transforms the void edge’s random structure into a regular one. After clustering and redundant scheduling, each node has an energy threshold. If a node’s energy is lower than its threshold, it sends a failure message to its cluster head which then uses the intersection angle with the failure node and considers all its neighbors as preparatory boundary nodes. Each preparatory boundary node is also judged. Thus a virtual rectangle is constructed. Its ability of covering the void which engenders dynamic intermediate destination nodes can enhance the efficiency and success of bypassing routing void. Compared with RGP and GPSR, simulation and analysis results demonstrate that EVRP is superior in finding the shortest routing path with higher delivery ratio, less control packet overhead and energy consumption.