Modulation Classification in Cognitive Radio

The automatic modulation classification (AMC) problem aims at identifying the modulation scheme of a given communication system with a high probability of success and in a short period of time. AMC has been used for decades in military applications in which friendly signals should be securely transmitted and received, whereas hostile signals must be located, identified and jammed (Gardner, 1988). More recently, the interest for AMC has been renewed by the research on cognitive radios (Haring et al., 2010; Wang & Wang, 2010; Xu et al., 2011), where AMC plays an important role in spectrum sensing (Haykin et al., 2009).