Novel multi-antenna spetrum sensing under Rayleigh fading in cognitive radio networks

This paper proposes a novel structure of multi-antenna spectrum sensing to solve the problem of the SNR Wall under harsh channel condition like deep fading. Our objective is to exploit the spatial diversity largely with resort to singular value decomposition (SVD) of the auto-correlation of the parallel signal flows. To evaluate its performance, the ROC of the proposed scheme is deduced in close form. Furthermore, normalized constellation distance is utilized as a criterion for measuring signal space under the same noise variance in comparing our proposed scheme with conventional energy detection. Simulation results reveal the significant performance enhancement especially in low SNR. This method can be applied widely, because it can be in the acylic primary user signal.