Performance of weighted cooperative spectrum sensing schemes in fading channels

Cognitive radio (CR) is a promising technology for efficient utilization of underutilized spectrum since it is able to detect the occupancy of primary users (PU) in the different parts of the spectrum. As the sensing channel uncertainties limit the reliably of the spectrum sensing decision, cooperation among multiple CR users is often used to improve the spectrum sensing decision. In this paper, the performance of single CR user and cooperative CR user (CSS) based spectrum sensing has been assessed in several channels such as AWGN, log-normal, Rayleigh and Nakagami fading channels. The performance of two spectrum sensing schemes based on assigning weights to CR users such as (a) weighting according to channel preference and (b) weighting according to the value of decision statistic are evaluated. The effects of fading parameters on missed detection performance of a CR user are indicated. Comparative performance of CSS under different fading channels has also been studied.