Analysis of optimal weighted cooperative spectrum sensing based on estimation of primary user signal power

This paper investigates a weighted gain combining cooperative spectrum sensing (W-CSS), which has the potential to achieve increased diversity gain and enhance detection performance. In previous works of W-CSS, weight is set based on estimated primary user (PU) signal power. However, their woks did not present an analysis of the detection performance of W-CSS. In this paper, we analyzed the statistics of the estimator and derived the detection probability of the W-CSS under time-invariant case. We also evaluated the proposed W-CSS under time-variant Rayleigh fading by computer simulations. We introduced an asymptotic nature of the P-CSS, i.e. the detection probability of the proposed W-CSS under time-variant Rayleigh fading asymptotically approaches the detection probability under time-invariant case as the number of antennas is increased.