Spectrum Sharing Performance Analysis And Channel Selection Strategy Research In Cognitive Radio Network

With the rapid growth of the requirement of the wireless communication, thelimitation and the unreasonable allocation of the spectrum resource force us to exploremore effective spectrum access mechanism and sharing strategy. As an intelligentwireless communication technology, Cognitive radio can effectively improve thespectrum utilization by the real-time interaction with communication environment andthe support on the spectrum resource sharing of space and time. But there are still manykey technologies to be broke through in Cognitive radio applications. Based on thenational science foundation project which named “the research of the topologymanagement of Mesh network, MAC mechanism and adaptive resource allocation ofcognitive radio”, the paper will focus on the study of spectrum sharing performanceanalysis and the channel selection strategy research: To build a new spectrum sharinganalysis model by studying the typical spectrum sharing models; To explore newchannel selection strategy through comparing and analyzing the characteristics andperformances of the existing channel selection strategies.First，the essential features and the involved key technologies of Cognitive radionetworks were analyzed; The development and research status of the cognitive radionetwork spectrum sharing technology and channel selection strategy both at home andabroad are introduced, based on that the challenges for two technologies are pointed out.Second，analysis of spectrum sharing performance: In view of the primary networkand cognitive radio network coexistence environment, four Spectrum sharing modelsare built under four kinds of access schemes which are random access scheme,real-reservation access scheme, pseudo-reservation access scheme and non-randomaccess scheme. Considering the scenario that several cognitive networks with finiteusers coexist, a Markov chain model is developed to analyze the performance of thepartial channel sharing policy in the cases with and without channel handoff. The partialchannel sharing policy then is compared with the static spectrum allocation policy andhierarchical sharing policy. The impact of variable user number on the spectrum handoffperformance is analyzed.Third，research on the channel selection strategy: four typical channel selectionmodels under auction mechanism，machine learning scheme，channel prediction schemeand optimization scheme are compared and analyzed. Based on the optimization scheme, the selfish channel selection algorithm and the cooperative channel selection algorithmare proposed in view of the heterogeneity of the channel. The selfish algorithm is tochoose the channel which can provide the maximum transmission rate for the secondaryusers (SU), and the cooperative algorithm is to choose the channel that benefits overallsystem throughput. The two algorithms are0compared with random channel selectionalgorithm after the establishment of simulation model.