Circuit for demodulating psk modulation signals

Abstract From the Canadian patent

In a differential-detection demodulator circuit a, PSK modulated signal is compared with a locally oscillated signal to obtain a phase difference between the two signals, whereupon the phase difference is demodulated. A phase detector circuit of the digital type outputs the phase difference signal. The digital phase comparator circuit compares plural reference signals, which give predetermined delays to the locally oscillated signals having carrier frequencies with the, inputted modulated signals. Preferably a pulse signal, having a phase difference between the inputted modulated signal and the locally oscillated signal is produced and the pulse width of this pulse signal is measured by a …