CLOCK SIGNAL SYNCHRONISATION DEVICE AND A DIFFERENTIAL PHASE DEMODULATOR COMPRISING SUCH A DEVICE

摘要

A device for the synchronization of a local timing signal to permit the demodulation of a differential phase-modulated carrier in synchronous data transmission systems. On the basis of a limited signal of the modulated carrier and a timing signal whose frequency is equal to quadruple that of the carrier, a logic element circuit comprising EXCLUSIVE-OR gates and synchronized flip-flops carries out a sequence of correlations and supplies pulses representative of the position of the phase jumps. These pulses are only used for the phase and frequency of the local timing signal.