Low Price to Win: Interactive scheme in cooperative cognitive radio networks

Cognitive radio provides an efficient technology to solve the problem of spectrum resource scarcity while cooperative communications can increase channel capacity. It is a common sense that combining the two benefits the system performance of cognitive radio networks (CRNs). A challenging problem of intelligent cooperation in CRNs is how to make control decisions when a secondary user cooperates with a primary user to get an optimal cooperation outcome. In this paper, we consider a scenario where a secondary user provides effort to the primary user to win the competition from many secondary users and simultaneously achieves optimal throughput. We establish a novel cooperation scheme termed Low Price to Win (LPW), and abstract the cooperation problem in CRNs as an optimization problem with multiple constraints. Unlike some traditional methods that provide direct solutions, we design a novel greedy algorithm using the Lyapunov optimization technique, by which the sophisticated optimization problem can be divided into a few subproblems and then cross-layer optimization can be applied. Our simulation results demonstrate the efficiency and effectiveness of the proposed algorithm.