Cooperative Cyclostationary Spectrum Sensing in Cognitive Radios at Low SNR Regimes

The paper proposes efficient cooperative cyclostationary spectrum sensing schemes in which each secondary user (SU) performs single-cycle cyclostationary detection for fast and simple implementation, while collaboration between SUs in final decision on the presence or absence of the primary user (PU) is explored to improve its performance. As the SUs simultaneously measure the spectral correlation functions at different cycle frequencies (CF) and exchange their information regarding the measured results, a sufficient number of CFs are effectively examined in a short period of time because of parallel searching, which makes the proposed cooperative spectrum sensing more reliable and faster. Performance of the proposed schemes in terms of false-alarm and detection probabilities and deflection coefficients is evaluated by analysis and simulation in AWGN, fading and shadowing channels. Illustrative results show that the proposed schemes outperform both single-cycle (SC) and multi-cycle (MC) cyclostationary detectors, especially in fading and shadowing channels.