International Journal of Advanced Research in Computer and Communication Engineering (IJARCCE)
Radio frequency spectrum is a very valuable resource in wireless communication. Its usage is increasing day-by-day at a tremendous rate. Since the available spectrum is limited, there is a need to find a way, to efficiently utilize this scarce spectrum. Cognitive radio is a huge step towards this. Cognitive radio helps the secondary users to use the unused licensed spectrum and drop out it when primary users are active. Spectrum sensing is a major function of cognitive radio. Commonly used spectrum sensing techniques are energy based spectrum sensing, matched filter spectrum sensing and cyclo-stationary based spectrum sensing.