Dynamic Spectrum Allocation in Cognitive Radio: Auction and Equilibrium

Cognitive radio is an emerging technique to improve the utilization of radio frequency spectrum in wireless communication networks. In this paper, we consider the problem of spectrum sharing among a few primary users and multiple secondary users through auction games. With the second-price auction and VCG auction, we adopt a utility function to obtain the optimal total payoffs the secondary users. User collusion and cooperation behaviors have been discussed by an interference graph. The simulation results show that user collusion usually deteriorate the efficiency of dynamic spectrum allocation and may cause instability of the communication system, while the cooperation among the secondary users can not only enhance the spectrum efficiency but also compensate the primary users through some cooperative mechanisms.