Classification of MFSK modulated signals using the mean of complex envelope

Modulation classification has many important applications in communications, e.g., reconfigurable receivers, spectrum managment and interference cancellation. In this paper we address the problem of classifying digitally modulated signals using cyclostationary statistics. We derive the first-order moments of the complex envelope of digitally modulated signals and verify their periodicity. A novel feature for the classification of the frequency shift keyed signals is proposed. The performance of this feature in distinguishing among different FSK constellations is studied in simulation. Some comparisons to commonly used features are performed.