A Novel Game Theoretic Utility Function for Power Control in Cognitive Radio Networks

In cognitive radio networks (CRNs), transmission power levels (TPLs) of secondary users (SUs) have a significant impact on system performance. As interference to primary users (PUs) increases with TPLs of SUs, whereas the Quality of service (QoS) of CRNs cannot be satisfied with low TPLs of its users. In this paper, we carefully investigate how to decide the TPLs of SUs by using non-cooperative game theory. We propose a novel utility function. Then a corresponding power control iterative algorithm is deduced based on it. The algorithm ensures not only the signal to interference plus noise ratio (SINR) of SUs above the required threshold but also proper TPLs of SUs. Formal proofs for the convergence of this iterative algorithm together with the existence of Nash Equilibrium are provided. Numerical results are presented to show that the proposed algorithm performs significantly better than traditional methods in the aspect of anti-noise.