Demodulation apparatus for phasemodulated telegraphic code

Claim 1

A DEMODULATION APPARATUS FOR A PHASE-MODULATED TELEGRAPHIC SIGNAL HAVING MULTIPLE PHASE POSITIONS EACH OF WHICH IS DETERMINED IN ACCORDANCE WITH POLARITY OF A TELEGRAPHIC CODE TO BE TRANSMITTED AND USING A PHASE POSITION OF AN IMMEDIATELY PRECEDING UNIT CODE ELEMENT OF REFERENCE, WHICH COMPRISES, A DEMODULATION CIRCUIT GENERATING A DEMODULATED SIGNAL CORRESPONDING TO SAID TELEGRAPHIC SIGNAL COMPRISING FIRST TERMINAL MEANS FOR RECEIVING SAID PHASE-MODULATED SIGNAL, SECOND TERMINAL MEANS FOR RECEIVING A REFERENCE CARRIER WAVE, A PHASE DETECTOR FOR DETECTING A MAGNITUDE AND SIGN OF A DIFFERENCE BETWEEN PHASE POSITIONS OF SAID TELEGRAPHIC SIGNAL APPLIED THERETO FROM SAID FIRST TERMINAL MEANS AND SAID REFERENCE CARRIER WAVE APPLIED THERETO FROM SAID SECOND TERMINAL MEANS AND OF THE SAME FREQUENCY AS SAID TELEGRAPHIC SIGNAL, SAID PHASE DETECTOR COMPRISING A RING MODULATOR HAVING AN OUTPUT COMPRISING A DIRECT CURRENT VOLTAGE, AN INTEGRATOR CONNECTED TO SAID PHASE DETECTOR FOR INTEGRATING THE DIRECTCURRENT VOLTAGE OF THE OUTPUT OF THE RING MODULATOR AT EVERY UNIT CODE ELEMENT OF SAID TELEGRAPHIC SIGNAL AND PRODUCING AN INTEGRATED SIGNAL SUCCESSIVELY HAVING A PLUS OR MINUS POLARITY ACCORDING TO THE SIGN OF SAID DIFFERENCE, PULSE MEANS RECEPTIVE OF SAID INTEGRATED SIGNAL FOR TRANSFORMING THE INTEGRATED SIGNAL INTO A PULSE SIGNAL OF PLUS