Spectrum sensing based on STBC higher order statistics for cognitive radio systems

In this paper, we treat the orthogonal space-time block coded signals. Those codes present a redundancy that can be exploited for the enhancement of the detection. We first study the classical energy detector based STBC and prove the benefits of spatial diversity in enhancing the capability of signal detection. Taking advantage of the Alamouti code structure, we propose two statistical metric tests based on high order moments and we evaluate their performances. Simulations results show that the proposed algorithms intend to offer better performance compared to the classical energy detector. Indeed, the first proposed metric test improves the performance in terms of the accuracy of the detection. In fact, the detection probability is improved by almost 18% at 1% false alarm. In the other hand, the second proposed metric offers better performance in terms of robustness to the noise uncertainty, 80% compared to the classical energy detector for an uncertainty level equal to 1 and 2dB.