Energy-efficient cooperative spectrum sensing for cognitive radio networks over fading channel: design and trade-offs

Abstract This paper examines and optimizes the Energy Efficiency (EE) of Cooperative Spectrum Sensing (CSS) in Cognitive Radio Networks (CRN). To protect the Primary User (PU) from the Secondary User (SU) transmission, an innovative mathematical formulation of the energy efficiency maximization problem has been developed. It takes into account the transmission time, sensing time, and number of SUs as design parameters. The study also examines the trade-off between sensing time and throughput, emphasizing the need for optimal sensing times to maximize throughput without excessive energy expenditure. Energy efficiency is explored in Rayleigh fading conditions, demonstrating that moderate fusion rule thresholds and a specific number of cooperating secondary users yield the best balance between accuracy and energy consumption. The simulation results show that the highest average EE within the tested range was observed at the optimum parameters with low sensitivity to nearby values. The proposed algorithm for CSS achieves a maximum EE of 2.362 Mbits/Hz/Joule, outperforming conventional methods by 42.3%, underscoring its efficacy in enhancing energy efficiency and spectrum utilization in cognitive radio networks.