Robust Reputation-Based Cooperative Spectrum Sensing via Imperfect Common Control Channel

Due to the fast-growing usage of wireless devices, cognitive radio networks have been proposed to address the spectrum scarcity problem. As the foundation of their practical applications, designing robust and secure spectrum sensing mechanisms is of great significance. In most existing works, the common control channel (CCC) is assumed to be perfect. However, this assumption may not hold in practice and imperfect CCC makes the existing methods against independent or cooperative data falsification attacks less effective. In this paper, we first analyze the impact of an imperfect CCC on the identification of malicious secondary users under independent and cooperative attacks. To better differentiate honest users and malicious users, a reputation threshold is derived for each secondary user. Based on the obtained reputation threshold, we propose a new reputation-based cooperative spectrum sensing method, which is validated to be robust against attacks under imperfect CCC. Extensive numerical simulations demonstrate the effectiveness of the proposed method.