Spectrum Sensing by Cepstral Covariance Detection

This work presents the cepstral covariance detector for spectrum sensing in cognitive radio. The power cepstral peaks of digitally modulated signals are exploited for spectrum sensing. To enhance the process of signal detection in low signal-to-noise ratio environments and with the knowledge of the data rate of the primary user signal, the cepstral covariance of the received signal is evaluated. The detection test statistic of the proposed detector is evaluated and an expression for the detection threshold is obtained under the null hypothesis. The detection performance of the proposed cepstrum-based detector is compared to covariance-based detectors and the obtained results validate its detection reliability at low signal-to-noise ratio levels with relatively low computational complexity.