Forward Based On Competition Of Multipath Interference To Avoid Ad Hoc Network Routing Protocol Research

Ad Hoc network is a communication system without any fixed infrastructure, which consists of a set of wireless mobile nodes. Ad Hoc Network is a fully distributed system, no need of any central entity, self-organizing, self-healing network. With the development of technology, the emergence of multimedia applications propose higher request to Ad Hoc Network routing protocol performance, how to provide QoS guarantee of multi-path routing protocol becomes a hot research topic, as well as a difficult research topic.There are many types of routing protocols. Multi-path routing protocols have many advantages in loading balancing, improving reliability and fault tolerance of routing protocols, so it is widely used. But, a lot of existing multi-path routing protocols do not think about Radio-disjoin among nodes on multiple paths, and compared with throughput increase of the single path routing, which is not obvious. Building a multi-path routing by flooding increases the network overhead, aggravates the overall network load.The MAC layer RTS/CTS mechanism uses the idea of interference nodes marking and competition forwarding to construct multi-path routing. Based on that, we propose Contention-based and Interference-free Multi-path Routing Protocol for Ad Hoc Network (CIMR). CIMR is divided into two parts:multi-path interference avoidance on routing’s construction and congestion control. The routing discovery is divided into three stages:initial transmission stage, competition forwarding stage and receiving stage. The routing discovery stage makes full use of competition forwarding, along with the MAC layer handshake mechanism, to forward data and identify nodes’interference state. In addition, we use the nodes’interference state to build multiple paths without interfering each other, which decreases network overhead and improves the throughput of the network. Through the congestion control strategy, source node can quickly perceive the existence of congestion in the path, thus to apply the congestion control mechanism to reduce the path send delay and packet loss rate.Finally, this paper makes the simulation experiments, according to movement speed and density of different nodes, and from three aspects of control overhead, the average transmission delay and average throughput to make the comparison and analyzes the performance of MR2protocol, AOMDV protocol and CIMR protocol. Simulation and experimental results show that the performance of CIMR protocol is better than MR2protocol and AOMDV protocol.