Cooperative spectrum sensing with censoring of cognitive radios and improved energy detector under LRT fusion

In this paper, performance of cooperative spectrum sensing (CSS) with likelihood ratio test (LRT) fusion at fusion center (FC) has been assessed in the presence of Rayleigh fading. Improved energy detector (IED) with multiple antennas has been used at each cognitive radio (CR) user where selection combining (SC) of decisions received from multiple antennas. Censoring of CR users has been considered based on quality of the reporting channels between CR users and a FC. Performance in terms of missed detection is evaluated for various values of improved energy detector parameter and number of antennas at each CR user. The performance in terms of total error probability has also been estimated for different values of normalized detection thresholds, sensing and reporting channel SNRs under both perfect and imperfect channel estimation.