Blind Estimator of Frequency Offset for Coherent M-PSK Systems

We address the issue of blind estimation of frequency offset for coherent M-ary phase shift keying (M-PSK) systems. An estimator is introduced, which is based on spectrum analysis of the signal's argument and multiple stages of amplifying and wrapping. Different from the previous estimators, it does not require the timing synchronization, data aid, the information of symbol rate and even the modulation type, and has lower implementation complexity. Through numerical simulation, it is found to be applicable in autonomous radio for M-PSK systems.