A Stackelberg game for relay selection and power allocation in an active cooperative model involving primary users and secondary users

Abstract

SummaryIn recent years, cooperative communications have been widely used to improve the spectrum efficiency in cognitive radio networks. In this paper, we propose a new cooperative model involving primary and secondary users, where a primary transmitter may select a number of the secondary users to act as relays in order to maximize its data rate and to transmit at lower energy level, thereby saving energy and reducing interference at the secondary base station. The cooperative transmission is a multiple two‐hop relaying scheme, which guarantees an achievable data rate exceeding that in the direct transmission. In the proposed approach, the problem of joint relay selection and power allocation is formulated as a Stackelberg game, which converges to a unique optimal Nash equilibrium. Performance evaluation shows that this model offers benefit to both sides, where the primary users achieve higher data rate at lower energy consumption and the signal to interference plus noise ratio at the secondary base station is increased significantly. In addition, the results show that the proposed solution outperforms the investigated models in terms of achievable data rate.