Spectrum Sensing by Parallel Pairs of Cross-Correlators and Comb Filters for OFDM Systems With Pilot Tones

This paper proposes a new spectrum sensing method for orthogonal frequency division multiplexing (OFDM) systems with pilot tones for equalization convenience. The time-domain signal cross-correlation (TDSC) method exploits the periodic feature of pilot signals embedded in time-domain OFDM signals, while random data signals deteriorate the detection performance. The new spectrum sensing method employs parallel pairs of cross-correlators and comb filters, reducing the effect of random data signals by comb filters. Simulation results of the proposed method demonstrate that the sensing performance for any given misdetection probability is improved by around 1.2 dB in SNR over the TDSC method.