Research Of Routing Protocol For Mobile Ad Hoc Networks Based On State Aware

With the rapid development of mobile communication technology and the scalable application of new wireless network, mobile ad hoc network (MANET), as one type of mobile communication networks, can provide available communication environment without base stations, so that it has been paid more and more attention in recent years. MANET is a full-distributed wireless packet network, and it has many characteristics, such as self-organized, self-managed and multi-hop. In this network, a mobile node has dual function. It is not only a terminal, but also a router at the same time. So it is extremely suitable for the military domain, the disaster relieving emergency and the sensor network, etc. The special application environment of MANET needs network protocols can offer better quality of service. However, research on MANET routing protocol is a challenge because of high channel bit error rate, the limited network resource, the limited energy of nodes, the frequent changed network topology and other similar reasons.This article focuses on state aware routing protocols for MANET, and has acquired some innovative research results. Firstly, it introduces the basic knowledge of MANET and analyzes the difficulties of researching on MANET. Secondly, MANET routing protocols and its' design problems are discussed. Finally, we address the present researches of state aware MANET routing protocols and the design thought of state aware routing protocols.Based on this, this article conducts a systematical study on state aware MANET routing protocols, and deeply analyzes the problems of state aware in MANET, then it brings three new state aware MANET routing protocols from different aspects.(1) According to the analysis and discussion of load state aware MANET routing protocols and current MANET routing algorithms, considering network characteristics and couplings between routes synthetically when choosing routes, a new load state aware MANET routing protocol is proposed. The new routing protocol combines load information that will be normalized and considers weighted coefficients separately. In special situations, it may give the corresponding estimation effects and choose the most excellent route consequently. Lastly, the performance analysis illustrates that this protocol has a preferable results.(2) Aimed at the limited energy problem in MANET, combining load aware technology, a new fuzzy logic and state aware routing protocol (FLSAR) is proposed. The new routing protocol translates load and energy into a language word by fuzzy rules. In the protocol, every node decides to forward the route request or not. The node will discard the route request if it is in the poor state. The destination node does not wait for more route requests but replies the first route request at once. So the communication route will be established. The simulations by NS2 illustrate that the throughput and lifetime of the network are improved to a great extent.(3) In view of the different communication service demands in some special application network, an improved protocol FLISAR based on FLSAR is proposed. The new routing protocol presents an integrated route metric which enables load and energy through defuzzification. The route request will collect and add the reciprocal of route metric when routing. It is certainly that the route request will be discarded if some middle nodes' reciprocal of route metric is less than that threshold. The destination node waits for a certain time to get more route requests and chooses the best route whose reciprocal of route metric is smallest to reply the route request. Comparing with the traditional MANET routing protocols, the simulations of protocol by NS2 illustrate and prove the preferable performances of FLISAR.We point out the deficiency of this paper and the problems to resolve in the end.