Optimal and Near-Optimal Spectrum Sensing of OFDM Signals in AWGN Channels
The authors consider spectrum sensing of OFDM signals in an AWGN channel. For the case of completely unknown noise and signal powers, they derive a GLRT detector based on empirical second-order statistics of the received data. The proposed GLRT detector exploits the non-stationary correlation structure of the OFDM signal and does not require any knowledge of the noise power or the signal power. The GLRT detector is compared to state-of-the-art OFDM signal detectors, and shown to improve the detection performance with 5 dB SNR in relevant cases.