A nonlinear optimized power control algorithm for multiuser cognitive networks

This paper presents the concepts of centralizing spectrum sharing scheme for cellular networks. We consider the scenario where the cognitive radio network is formed by secondary users with low power personal/portable devices and when both systems are operating simultaneously based on co-channel spectrum sharing. The goal of this paper is to study how to maximize the utilities of the cognitive network given certain interference limits to ensure QoS requirements of primary users. The power optimization problem is formulated as a nonlinear and convex problem. Then a Reduced Gradient Method (RGM) is implemented to solve this problem and find the answer. Our work provides a theoretical analysis on the power control performance that motivates further research on designing more practical transmission schemes in future cognitive networks.