Novel energy-efficient reporting scheme for spectrum sensing results in cognitive radio

Energy efficiency during spectrum sensing in cognitive radio has received a lot of attention during recent years. Such issue becomes challenging, especially with battery-powered terminals, because of its direct influence on achievable performance represented by detection accuracy. In this paper, we present a novel reporting scheme for spectrum sensing results, which significantly reduces the energy consumption without any effect on the detection accuracy. The proposed scheme is based on the observation that sensing results are consecutively reported to a Fusion Center (FC), which allows the FC to terminate the process whenever the received results are enough to make a decision according to the employed Fusion Rule (FR). Hence, the energy consumed in results´ reporting is reduced as the number of reporting users is lower. Mathematical expressions for the average number of reporting users for several FRs are obtained. Simulation and analytical results show a significant reduction of the energy consumption.