Dynamic Spectrum Sharing Based On Game Theory In Cognitive Radio Network

Improve spectrum utilization in order to meet the growing demand of communication is an eternal topic in the field of wireless network, While cognitive wireless networks is considered as a key technology to solve this problem.This paper described the cognitive wireless networks and its key technology, then made spectrum sharing based on Game Theory in two parts: In the first part, bringing bilateral market model, a double dynamic spectrum allocation algorithm based on set bid permutation algorithm is proposed. To take the individual-rationality of the participants into account, we model the game between two parties of the auction as the game between cognitive users. In auctions, each cognitive users bid independently. Then the auctioneer divides the cognitive users set and allocation spectrum resource according to cognitive users set bid, real payments and winners of two parties. After obtaining the results, the auctioneer sort the buyers and sellers’ offer in order and determine the auction outcome, finally forming many-for-one mapping relationships between buyers and sellers. The theoretical analysis and simulation result proves that our proposed algorithm preserves truthfulness, individual-rationality and fairness. In the second part, in order to address the problem of spectrum access statistics with mobile primary users in cognitive wireless networks, a spectrum access strategy based on mobile primary user is proposed. First, an optimal primary users’ protection distance is proposed to ensure its normal communication. Then, channel availability based on the two dynamic markov chain is dynamically modeled by estimate the relevant distance between primary user and secondary user. Finally, the optimal channel selection strategy is derived by making full advantages of primary users’ spatial temporary channel using strategy, namely Nash equilibrium. Simulation results illustrate that the proposed strategy can improve the throughput of secondary link and ensure fairness even when it comes to increased secondary users’ density.