Simplified DFT: A novel method for wideband spectrum sensing in cognitive radio

Four simplified discrete Fourier transform (SDFT)-based spectrum sensing methods are introduced for power spectral density (PSD) estimation for cognitive radio (CR). The SDFT-based spectrum sensing techniques are less computationally complex than DFT techniques since no multiplications are required in the time-to-frequency domain conversion process. The simulation results and mathematical analyses indicate that the performance of the SDFT-based spectrum sensing method is comparable to that of the DFT-based one when the received signal spectrum is lightly occupied.