Spectrum Sensing in Cognitive Radio Based on Energy Detection

Cognitive radio(CR) is viewed as a novel approach for improving utilization of the precious radio spectrum.This paper first reviews the background and concepts of CR,and then investigates energy-detection based spectrum sensing by focusing on the spectrum sensing function.To deal with the problem of local sensing characteristic in wireless signal detections in the energy detection process,a distributed M-cooperative detection scheme is presented.Analytical detection probability based on the "OR" rule is presented.Both simulation and the analytical results indicate that,with a small tradeoff between detection probability and false alarm probability,the scheme significantly improves the spectrum sensing ability under low SNR.