Sample timing control for demodulation of phase-modulated signals

Abstract From the Canadian patent

A phase-modulated signal such as a quadrature phase-shift-keyed (QPSK) signal in, a wireless communication system is demodulated using sample timing based at least in part, on frequency information generated by frequency demodulating the phasemodulated signal. The phase-modulated signal is separated into first and second portions the , first portion is, phase demodulated to generate demodulated symbols and the second portion is , frequency, demodulated to generate e.g. a measure of the instantaneous frequency of the phase-modulated signal. The instantaneous frequency measure is processed to identify one or, more symbol transitions and the identified transitions are used to establish …