A Study Of Clusteirng Routing Protocol For Cognitive Radio Ad Hoc Networks

With the rapid development of various demands and applications of wireless communicationnetworks and radio technologies, the increasingly tense issue of spectrum resources has emerged.However, the existing spectrum management and allocation policies have led to the unbalancedutilization of current spectrum resources. Most allocated spectrum has not been fully utilized,whereas some hot ones are overloaded. Cognitive radio technology is an important means to solvethe growing shortage of spectrum resources. Nowadays, the researches on underlying technologiesof CR networks have become mature, but the studies of network layer or above are just gettingstarted. Morever, the core functionality of CRNs should rely on the design of routing protocols.This paper mainly conducts researches on routing protocols and related issues of CRNs ofclustered Ad Hoc situation. The paper firstly analyzes the basic characteristics of network scenariosand unresolved problems in network layer about the routing protocols to be designed. Then forsolving the problems of heavy broadcast overheads and poor searching quality of paths during theroute discovery of routing protocol, a hybrid routing protocol FDBRNP of CC_RREQ forwardingdecision of broadcast mechanism based on RSSI and neighbor priori-knowledge is designed. Basedon two-hop range of neighbor node table, by calculating the average RSSI and average traffic-loadof neighbor nodes during route discovery process, the protocol integratedly decide whether or not toforward routing packet CC_RREQ, and nodes which are not satisfied with the decision conditionswill start a back-off delay mechanism to compete forwarding priority of the routing packet.FDBRNP routing protocol effectively optimizes both the routing broadcast overhead and routesearching quality problems.After designing the routing protocol FDBRNP, based on the network scenarios the paperestablishes an integrated network simulation model of MATLAB programs, and analyzes thecorresponding performance of simulation results of routing protocol. Simulation results show that,compared with the classic routing protocol CBRP, the FDBRNP protocol significantly makes betterin aspects of the network performance of normalized routing overhead and average end-to-enddelay etc. Consequently, the routing protocol meets the needs of network scenarios and possessessome actual values of application.