CIRCUIT FOR DEMODULATING PSK MODULATED SIGNAL BY DIFFERENTIAL-DETECTION

摘要

In a demodulator circuit which is simple in construction, a PSK modulated signal is converted in frequency into a quasibase band signal and is then subjected to complex separation. Partly since a phase angle sampled from a digital complex signal is supplied to a differential-detector circuit, and partly since the differential-detector circuit processes only the phase angle, the differential-detector circuit has a simple construction. As the detected phase difference between two successive symbol data, an error between a carrier wave contained in the modulated signal and a locally oscillated frequency on the receiving side is compensated and is outputted as a digital demodulated signal.