On optimal relay power allocation in energy efficient cognitive radio networks

An energy-efficient amplify-and-forward relay assisted cognitive radio system design is proposed that simultaneously considers the issue of cooperative spectrum sensing and secondary data transmission. The problem is mathematically formulated as minimization of total energy consumption under the constraints of sensing reliability (in terms of detection and false alarm probabilities), secondary user throughput and interference threshold to primary user. Simulation results show that there exists an optimal relay power gain that minimizes energy consumption.