Cooperative spectrum sensing with censoring of cognitive radios in Rayleigh fading under majority logic fusion

In this paper, the performance of cooperative spectrum sensing (CSS) has been assessed in presence of Rayleigh fading. A cognitive radio (CR) senses the primary users (PUs) using an energy detector (ED) in sensing channel (S-channel). If a CR is selected to transmit its local decisions to a fusion centre (FC), it does so using a reporting (R)-channel with binary phase shift keying (BPSK) signaling. In the present work, we consider censoring of CRs based on a characterization of Rayleigh faded R-channels. In other words, CRs, whose estimated R-channel fading coefficient towards the FC exceeds a predefined threshold, are allowed to transmit. Majority logic fusion is considered at the FC to estimate the performance in terms of average missed detection and total error probabilities for various values of censoring threshold, number of CRs, false alarm probabilities, average S-channel and R-channel SNRs, under both perfect and imperfect channel estimations.