Minimax games for cooperative spectrum sensing in a centralized cognitive radio network in the presence of interferers

In this paper, we consider the problem of interferers for cooperative spectrum sensing in a centralized cognitive radio network comprising N cognitive radios (CRs) and one fusion center (FC) in the presence of a fixed interferer. The design metric chosen is the error probability. We prove the existence of a saddle-point in the minimax game between the interferer and the CR network. An optimal solution is found that maximizes the objective with respect to the interferer´s parameters and minimizes the same with respect to the CR network´s parameters. We show that the probability of error is a quasi-convex function with respect to the network´s parameters and a monotone function with respect to the interferer´s parameters. We also present numerical results that corroborate our theoretical results.