Design And Implementation Of Adaptive Routing Scheme Supporting Multiple Relaying Methods

Taking full advantage of the broadcast nature of the wireless channel,cooperative communication technique enhances the quality of transmission by cooperation among nodes in wireless networks,and has become one of the most rapidly developed research fields.As a promising cooperative communication technique,network coding attracts much attention due to its ability to improve the performance of wireless networks.This thesis focuses on the implementation of network coding in multi-hop wireless networks,which mainly involves the development of a simulation platform supporting networking and the design and simulation of a IP protocol supporting multiple relaying methods on the simulation platform.With the development of cooperative communication technologies,the requirements of simulation platform are also increasing.Current simulation platforms in the market usually need a long period of simulation time because of their single model and complex function.More importantly,a complete process of using network coding to transmit packets requires the cross-layer collaboration of network layer,MAC layer and physical layer.However,most of existing simulation platforms do not support cross-layer protocol simulation.This thesis developes a simple and flexible wireless simulation platform based on the idea of discrete event simulator using C++ programming language.The wireless simulation platform developed in this thesis can support the design and simulation of the protocol and algorithm better in network layer.To apply network coding to general multi-hop networks,and solve the problems that traditional coding aware routing schemes such as COPE can't detect coding opportunities actively and the coding conditions are limited to two hops,in this thesis,a IP protocol supporting multiple relaying methods is proposed.This thesis design a new routing criterion based on ETX which is not only coding aware in multi-hops but also considers both inter and intra flow interference.In order to reduce delay and routing overhead,this thesis propose another routing criterion based on queue length.Finally,the effectiveness of routing schemes verified in the wireless simulation platform.Simulation result indicates that the protocol which supports network coding brings more throughput improvement than the protocol which doesn't support network coding in the wireless multi-hop networks.The simulation also shows that the wireless simulation platform developed in this thesis implement cross-layer simulation easily.