A Novel Cross-Correlation Combining Based Spectrum Sensing Approach

It is well known that the performance of the energy detector necessitates a prior knowledge about noise variance and gravely degraded for low SNR. In this paper, we proposed a novel combined second order moment, CSOM, based multiple antennas sensing. Its performance does not depend asymptotically on the noise variance. Simulations show decision accuracy improvement compared to the classical square law combining SLC based energy detector. In fact, the spectral efficiency is enhanced (low P_fa) while maintaining low interference level with the primary user PU (high P_d). Besides, the provided simulations exhibit that the best decision accuracy is reached for few combining numbers (almost the half of all possible combinations) unlike what is usually known for classical multiple antennas combining schemes.