Research On Service-oriented Dynamic Spectrum Access Access Algorithm In Cognitive Wireless Networks

Along with the high speed development of wireless networks and continuousspringing up of wireless terminals, people are having more demands on internet andwireless multi-media business. However, the lack of spectrum is becoming thebottleneck of wireless telecommunication development. The cognitive radio networkscould real-timely perceive the neighboring network environment, reset the networkconfiguration of wireless modulation mode and spectrum scope of telecommunicationaccording to its needs, and access the idle spectrum freely, so as to increase theoccupation efficiency of wireless channels and relieve the spectrum tense.As the revolutionary solution to shortage of spectrum, the cognitive wirelessnetwork technology is recently popular in wireless telecommunication research field.This essay mainly talks about the spectrum dynamic allocation, and establishesprofound research therein. Based on the analysis and sum-up of large amount ofspectrum allocation models, this paper mainly improves the graph model and particleswarm model, and proposes the users service oriented dynamic spectrum allocationmethod. In addition, this paper realizes the dynamic spectrum access technology onthe basis of USRP N210and GNU Radio. The main creative research results show asfollows:（1） Research on users’ service oriented spectrum dynamic allocationmechanism using graph method. By improvements to present graph theory method,and comprehensive analysis to the relations between business types of different usersand characteristic parameters of different spectrum resources, I construct numbers ofsub-reward matrix in the graph theory model, propose one multi-rewardsnormalization model on the basis of fuzzy reasoning, and obtain one morecomprehensive and complete reward figure. What’s more, this paper conductssimulated analysis to the algorithm and proves its improved spectrum allocationreward as well as improvements to whole network reward and fairness, anddistribution service to users. （2） To the possible NP problem remaining for multi-users, considering themerits of bio-inspired algorithm, here we use particle swarm, it adapts the improvedPSO model into the user oriented dynamic spectrum allocation algorithm to analyzeand verify whether the improved algorithm could further improve the algorithmperformance and increase the convergence efficiency.（3） With support of USRP N210device and GNU Radio platform, I designand realize the basic platform of cognitive wireless network. Also I realize thehistorical information based, user’s cost service oriented dynamic spectrum accessalgorithm according to activity of primary users, and finally the system isdemonstrated and the property is tested.As cognitive wireless network is a promising topic, this paper mainly researchedon the spectrum dynamic allocation mechanism which is the key technology ofcognitive wireless network. It, using the base idea of service-oriented, not onlyproposed two improved spectrum allocation algorithms, but also realizes the dynamicspectrum access using in cognitive wireless network on the basis of actual platform,and lays a foundation for further application of spectrum access algorithm.