Energy detection of narrowband signals in cognitive radio systems

In this paper, we consider energy detection based spectrum sensing for narrowband signals in a wideband cognitive radio system using OFDM. The effect of fast Fourier transform (FFT) size on detecting narrowband signals is analyzed, and appropriate FFT size is suggested to improve the probability of detection. In order to reduce complexity, an improved spectrum sensing scheme is proposed to improve the detection probability without increasing the implementation complexity. Simulations are performed to verify the presented schemes.