Blind Spectrum Sensing of OFDM Signals under Multipath Fading Channels
Ming He, Ming Jin, Youming Li · 2018
This work presents a blind detector for sensing orthogonal frequency division multiplexing (OFDM) signals under multiple fading channels. The detector exploits the fact that the AWGN at secondary receivers has a flat power spectral density, while the received OFDM signal under multipath fading channels does not. Closed form expression of the decision threshold is provided. It is shown that the decision threshold is independent of the number of samples. In addition, the proposed detector is robust against frequency offsets. Numerical results demonstrate the superior performance of the proposed detector.