Design And Implementation Of MAC Protocol Supporting Multiple Modes Of PNC On A Simulator

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,physical-layer network coding(PNC)attracts much attention due to its ability to improve the performance of wireless networks.This thesis focuses on the implementation of PNC in multi-hop wireless networks,which mainly involves the development of a simulation platform supporting PNC and the design and simulation of a MAC protocol supporting different modes of PNC 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 PNC 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 and below.To apply PNC to general multi-hop networks,in this thesis,a MAC protocol supporting bidirectional model of PNC(PNC-MAC)is proposed.PNC-MAC which supports simultaneous data transmission is based on the carrier sense multiple access with collision avoidance(CSMA/CA)mechanism and is regarded as an extension to the IEEE 802.11 MAC protocol.While PNC is not suitable for the network,PNC-MAC selects conventional network coding or conventional relaying method to transmit packets.Simulation result shows that PNC-MAC improves the performance of muti-hop networks.Considering that unidirectional flows model also exists in many wireless network applications,another protocol called OPNC-MAC supporting unidirectional model and overhearing is proposed which is a supplement of PNC-MAC.Finally,the effectiveness of PNC-MAC and OPNC-MAC protocol is verified in the wireless simulation platform.Simulation result indicates that the protocol which supports PNC brings more throughput improvement than the protocol which doesn't support PNC in the wireless multi-hop networks.The simulation also shows that the wireless simulation platform developed in this thesis implement cross-layer simulation easily,and supports different modes of PNC.