Research On Technologies Of Collaborative Spectrum Sensing Based On Coalition Game In Cognitive Radio Networks

With the rapid evolution of the wireless communications in the broadband,seamless, intelligent direction , the dependence on radio spectrum resource has been growing. At present, the way of specific industry business fixed allocation for spectrum often bring up uneven distribution of resources. To solve this problem, the only way is to reuse the spectrum and improve the utility of spectrum resource. Cognitive radio technology as a smart spectrum sharing technologies will be effective in alleviating these contradictions. Through sensing frequency domain,time domain and space domain, it can automatically search and occupy free licensed spectrum, reuse the non-renewable resources.In this dissertation,we analyzes the various existing ways of spectrum sensing and the basic concept in game theory. Then an analyze process based on game theory for cognitive radio networks is established and a dynamic game model in cognitive radio for spectrum sensing is proposed. We compare the optimal proportion that the secondary users participate in spectrum sensing and the average throughput achieved in the cooperative sensing game with different number of secondary users. Combining the concept of coalition game, we propose a spectrum sensing algorithm based on coalition game; then considering the complexity of the proposed algorithm, we propose a distributed algorithm which using the simple merge–spite rules to achieve the stability states. Finally, we proposed the parameterδnamed coalition distance regulation factor to characterize the role of distance in the alliance strategy which can effective control of the process and the size of coalition formation. After analyzing the stable of coalition spectrum sensing algorithm, we simulate different algorithms and compare the false alarm probability, missing detection probability variations in the cognitive networks with the number of the second users increasing, and also show the changes of the union as the network topology changes. Secondary user can also recognize change in the network, look for a suitable alliance strategy using coalition game in cooperative spectrum sensing.