Research And Implementation On MAC Layer Of WiMAX System With Mesh Mode

Wireless Mesh Network (WMN) has the specialty of configuring itself and organizingitself. No center node is needed for managing and controlling. Each node has the ability tocoordinate messages, schedule data, and select the best route to transmit. WMN has greatadvantage in robustness and flexibility, as a result it has important application in many fields.However, researchs and development is mostly focused on PMP mode, it isn’t reported thatany development has been finished in the country.The topic of this thesis is based on the project “Research and Implementation of WirelessMesh Backbone Network Basing on Crossing Layers”. The purpose is to implement asoftware system based on IEEE802.16d protocol, which is aiming at coordinating messagesand transmitting data without collision.In this thesis, the IEEE802.16d Mesh mode MAC protocol process is analyzed in detail,including protocol model, address and link, protocol data unit, frame structure and schedulingscheme. Base upon the analysis, the system is divided into different modules. Neighbor List isused to storage information of neighbor nodes. Control Plane is responsible for initial accessnetwork. Coordinator calculates the right time to transmit messages. Classifier will classifytraffic data from upper layer and do the matching with links. Data Plane is responsible forfragmentation, packing and concatenation. Scheduler will request and grant bandwidthaccording to the resource. The detail of each module in the software design scheme is given,including data structure, algorithm and software flow chart.To verify functions of the system, the thesis design three experiments for it, includinginitial access network experiment for Control Plane, calculating transmitting opportunityexperiment for Neighbor List and Coordinator, bandwidth request and data transmittingexperiment for Classifier, Data Plane, Scheduler. The result of the experiments shows that thesystem functions well and fulfils basic requirement of the Mesh mode, the system coordinatesmessages and schedule data transmitting without collision.