Ad Hoc Network Routing Protocols

Ad Hoc network is a kind of wireless and mobile network develops in recent years. It has a dynamic and variable topology, each node not only can move but can join or exit the network freely. It has an acentric and infrastructureless distributed multi-hop structure, all nodes have an equal status and act as two roles-router and node itself.Routing technique is the key technique of Ad Hoc network and one of the most important factors affect the performance of the network. As the dynamic and variable topology, those traditional routing protocols can not be applicable to Ad Hoc network and new routing protocol must be designed. In recent years, some special routing protocols for Ad Hoc network appeared such as AODV, DSR and DSDV. But to the whole fields of Ad Hoc routing techniques especially QoS routing technique, still has a long way to go, all those routing protocols are need to be improved as there is no any standard protocol exists for Ad Hoc network. Ad Hoc routing technique needs a further research and development.The dissertation studied Ad Hoc routing protocols in detail. We analyzed and compared the performance of several Ad Hoc routing protocols with NS-2 under different network environment. In order to enhance the performance of routing protocol AODV, we made an improvement based on retreat algorithm on MAC layer. The improved-AODV has a better performance on routing spending than traditional AODV when the network has a big load.In the text, we put forward one new Ad Hoc routing protocol called SQRP-OP (A Steady QoS Routing Protocol Based On Prediction for Ad Hoc Networks). SQRP-OP choose the most stable path transmit data based on the prediction to nodes' location, it decreases the probability of routing broken and reconstruction and enhances data successful transmission rate. The protocol use a directional flooding routing algorithm with band-limited and resource reservation scheme to found a successful route, so it can provide the data transmission with reliable QoS guarantee and decreases routing spending.The content of the dissertation mainly including five parts as follows:In chapter one, we give a brief introduction to the concept and development of Ad Hoc network and routing protocols.In chapter two, we compared the performance of Ad Hoc routing protocols in detail and proposed some schemes which can improve the peformance of Ad Hoc networks.In chapter three, we compared and analyzed the performance of several Ad Hoc routing protocols through network simulation with NS-2, and we also provide an improved schemes for AODV based on retreat algorithm on MAC layer in this part.In chapter four, firstly, we analyzed Ad Hoc QoS routing techniques and Ad Hoc routing protocols that based on prediction to nodes' location. Then, we put forward one Ad Hoc QoS routing protocol based on prediction called SQRP-OP, the description of the protocol and algorithm was given as follows. At last, we did a analysis to the protocol SQRP-OP.The fifth chapter is the last part of the dissertation, we draw a conclusion of the whole dissertation and made an expectation to further research and development of Ad Hoc routing technique.