Digital modulation classification in flat-fading channels

This paper addresses the problem of classifying digital modulations in a Rayleigh fading environment. The first step of the proposed classifier consists of estimating the parameters unknown by the receiver, i.e., the fading amplitude, phase offset, and residual carrier frequency. These unknown parameters appearing in the class conditional densities are then replaced by their estimates, resulting in a so-called plug-in classifier. The performance of this classifier is compared to another classification strategy recently proposed to solve the modulation classification problem in a fading environment.