Multipath Routing Protocol Research In Wireless Sensor Networks

Wireless sensor network is a large collection of sensor nodes with limited power supply and constrained computational capability. Due to the restricted communication range and high density of sensor nodes, packet forwarding in sensor networks is usually performed through multi-hop data transmission. Therefore, routing in wireless sensor networks has been considered an important research field over the past decade. Nowadays, multipath routing approach is widely used in wireless sensor networks to improve network performance through efficient utilization of available network resources.In order to design robust routing protocol, the paper designs a geographic and energy efficient multipath routing protocol named GEMR.The GEMR protocol is based on the traditional single-path routing protocol GPSR. First, we describe and analyze the GPSR protocol detailedly.Then,in order to overcome the drawbacks of the GPSR protocol,we propose the GEMR protocol. GEMR considers the residual energy and the distance to the sink node when setting up the route. And the GEMR protocol can set up a primary path and multiple alternate paths and adjust the number of alternate paths according to the application environment. Finally, in order to solve the congestion problem,we propose a multipath buffer congestion control mechanism MBCC. This mechanism uses double buffering threshold to detect congestion, and use two methods to avoid and alleviate congestion:decrease transmission rate of the end system and transfer the flow to alternate path.This mechanism can detect and control congestion of GEMR protocol very effectively.The Matlab simulation results showed that:compared with the k-MGPSR protocol,the GEMR protocol can save energy, balance the network energy consumption and prolong the network lifetime.And GEMR outperformace the GPSR protocol in terms of the reliability of data transmission and network lifetime too.