Strategy Analysis of an Evolutionary Spectrum Sensing Game

Evolutionary game has been shown to greatly improve the spectrum sensing performance in cognitive radio. However, as selfish users are shortsighted for the long-term profits, they are not willing to collaborate to sense. In this paper, we propose an evolutionary spectrum sensing game to improve the long-term spectrum utilization. The new spectrum sensing model takes advantage of the long-term effect of the future actions on the current actions by using the concept of present value (PV) in repeated game. The collaboration conditions of two strategies, i.e., tit-for-tat and grim strategy are discussed. It is proved that the grim strategy can enhance secondary users' sensing positivity greatly, and so is the overall spectrum efficiency. Finally these new developments are illustrated in our experiments.