Enhanced two-step spectrum sensing algorithm for OFDM signal

In-band pilot and cyclic prefix (CP)-based sensing, exploiting OFDM signal characteristics in the frequency domain and time domain respectively, are two effective techniques for low SNR spectrum sensing in cognitive radio communications. This paper seeks the theoretical performance improvement and optimal solution on the combination of these two techniques. The principles and performances of these two sensing algorithms are firstly introduced in this paper. An enhanced two-step spectrum sensing algorithm, which jointly explores characteristics of in-band pilots and cyclic prefix, is proposed subsequently. System performance improvement of the proposed algorithm, comparing to these two sensing techniques, is confirmed with theoretical analysis and simulations.