Comparison of Primary Transmitter Detection based Spectrum Sensing Techniques in Cognitive Radio Systems

Cognitive Radios aim to implement dynamic frequency usage which is proposed to increase the efficiency of the spectrum and can sense their environment, detect the idle bands and then allocate the secondary users into the detected idle bands without any interference to primary users‟ communications. There are three main techniques for spectrum sensing: primary transmitter detection, cooperative detection and interference based detection. This paper focuses on sensing the idle bands using transmitter detection techniques in Cognitive Radio based systems. Generally transmitter detection includes three techniques: energy detection, matched filter detection and cyclostationary feature detection. Using simulations, a comparative analysis of the three techniques has been carried out in terms of power spectral density for low signal to noise ratio. It has been found that energy detection out performs the other techniques by means of detection probability and also the sensing time is less as compared to cyclostationary feature detection. Hence, Energy detection does not require the prior knowledge about the Primary signal. The simulation results are analyzed.