A blind power differentiation scheme for energy detection-based spectrum sensing

The performance of energy detection-based spectrum sensing is greatly compromised by the problem of noise uncertainty consisting of device noise uncertainty and environmental interference uncertainty. This paper first compares these two kinds of uncertainties and comes to the conclusion that the environmental interference dominates the noise uncertainty problem. Aiming at alleviating the environmental interference, this paper proposed a power differentiation scheme to differentiate the target primary signal from the environmental interference produced by the simultaneously transmitted secondary signals and the device noise. The differentiated target primary signal power, rather than the total received composited power used in most conventional schemes, is used to construct the test statics for the energy detection to improve the sensing performance. The proposed power differentiation scheme does not require any prior knowledge of the primary signal except the geolocations of the primary transmitters and secondary users, thus, is a noncoherent scheme. Simulation results show that the proposed scheme can effectively cope with the environmental interference and can greatly improve the performance of energy detection-based spectrum sensing.