Energy-efficient cooperative sensing scheme based on censoring for cognitive radio networks

In this paper, we propose a novel censor-based cooperative spectrum sensing strategies, called adaptive energy-efficient sensing (AES), in which both sequential sensing and censoring are employed, aiming to reduce the sensing energy consumption of secondary user relays (SRs). In AES, an anchor secondary user (SU) requires cooperative sensing only when it does not detect the presence of PU by itself. We derive the analytical expressions of false alarm and detection probabilities over Rayleigh fading channels for AES. The sensing energy consumption is also analyzed. Then, we study sensing energy overhead minimization problem and show that the sensing time allocation can be optimized to minimize the miss detection probability. Finally, Numerical results show that the proposed strategies can remarkably reduce the sensing energy consumption with slightly degrading the detection performance compared with traditional scheme.