Design And Simulated Implementation Of Game-Based Dynamic Spectrum Management Mechanisms

With the rapid development of wireless communication technology, increasingly popularization of wireless devices and continuous increase of new traffic, the problem of spectrum shortage and spectrum efficiency low becomes increasingly serious. At present, the mode of static spectrum allocation adopted by spectrum management, some unlicensed spectrum is very crowded, but some authorized spectrum utilization rate is very low. Cognitive radio technology is a kind of technology which could effectively and dynamically manage spectrum, could satisfy the requirements of the spectrum to people and improve QoS (Quality of Service) as much as possible. In the cognitive environment of heterogeneous primary users and secondary users in multipath fading and shadow effect, how to fair and effective managing dynamic spectrum is an urgent need in the development of wireless communication.According to the cognitive environment, the network model is given firstly, and then its related parameters are depicted, the two key problems that spectrum sensing and spectrum sharing in the dynamic spectrum management are studied by the game theory finally. In order to study the fairness problem in dynamic spectrum management, defines the fairness of spectrum sensing and spectrum sharing are defined.When secondary users in the cognitive environment, a coalitional game-based spectrum sensing mechanism is proposed in order to fairly execute spectrum sensing and form the group needed by evolutionary game. The method of calculating the basic parameters of spectrum sensing is introduced firstly, and then the spectrum sensing problem is modeled as a coalitional game with a nontransferable utility, and next a coalitional rule of satisfying the Pareto Optimality is designed, the detailed implementation steps of this mechanism is given finally. According to the results of the spectrum sensing, an evolutional game-based spectrum sharing mechanism is proposed in order to make the secondary users to be able to fairly share spectrum according to the secondary user satisfaction degree and wireless channel condition. Because the cognitive radio network is dynamic and heterogeneous, and the wireless channel is unreliable and easy affected by environmental, the knowledge of fuzzy mathematics is introduced to characterization the parameters related to the secondary user satisfaction degree. The evolutional game is used to model the spectrum sharing between the cognitive users, the fairness of spectrum sharing considered in the utility function, the dynamic equilibrium solved according to the replicator dynamic equation, and the detailed implementation steps of the mechanism given finally.The dynamic spectrum management mechanisms are simulated over VC++, and a performance evaluation is performed. Compared with the benchmark algorithm to analyzed performance, it was found that the spectrum sensing mechanism proposed in this thesis is better than the benchmark algorithm in term of the detection probability and the user utility of spectrum sensing, and the spectrum sharing mechanism proposed in this thesis is better than the benchmark algorithm in term of the user of spectrum sharing.