Universal Carrier Recovery Loop for QASK and PSK Signal Sets

A new carrier recovery loop which applies to quadrature amplitude shift keying (QASK) and phase shift keying (PSK) modulation schemes is presented. This loop is shown to provide significant advantages compared with those already used. Furthermore, the baseband processing of the demodulated signals allows an easy implementation, especially for high-speed digital modems. Both geometrical interpretation and theoretical justification using estimation criteria are provided. Finally, experimental results are reported.