An efficient game-based competitive spectrum offering scheme in cognitive radio networks with dynamic topology

In practical cognitive radio networks, the topology is constantly changing since the primary and secondary users join and leave the network at any moment. So it is very important to design a distributed spectrum offering scheme that can coordinate the spectrum offering scheme adapt to dynamic topology with only local information. In this paper, we propose a game-based distributed spectrum offering scheme in cognitive radio network with dynamic topology in which multiple primary users with spectrum opportunity compete with each other to offer spectrum access to the secondary users. We obtain the Nash equilibrium of the game and analyze the impacts of the dynamic topology on the Nash equilibrium. In addition, we present a iterative distributed spectrum offering algorithm for the case when the primary users can not observe the current action and utility adopted by others. We theoretically prove that the algorithm can converge to Nash equilibrium within a few iterative steps. The simulation results show that the proposed scheme can achieve better performances.