Blind Multiuser Detection in Nakagami-m Fading Channels with Impulsive Noise

Experimental results have confirmed the presence of impulsive (heavy-tailed) noise in different wireless communication channels. In direct sequence-code division multiple accesses (DS-CDMA) systems, the signals are transmitted over multipath channels that introduce fading. Multipath fading along with multiple access interference (MAI) and inter-symbol interference (ISI) in impulsive noise environment degrades the system performance. This paper presents a technique for blind multiuser detection in DS-CDMA communication systems over Nakagami-m fading channels with impulsive non-Gaussian noise. Expression for average probability of error of an M-decorrelator is derived for the demodulation of BPSK signals over single-path Nakagami-m fading channel. A new M-estimator is proposed for robustifying the detector and its performance is studied and analyzed by evaluating probability of error with the derived expression. Simulation results indicate that the proposed blind multiuser detector performs better in highly impulsive noise environment.