Cipher system for pulse code modulation communication system

Claim 1

IN A COMMUNICATION SYSTEM A SOURCE OF ON-OFF PULSES IN PERMUTATION CODE GROUPS REPRESENTATIVE OF THE MESSAGE WAVE AND CIPHERED BY THE REENTRANT ADDITION OF THE SEQUENCE OF PULSES WITH THE SAME SEQUENCE DELAYED BY A PREDETERMINED INTEGRAL NUMBER OF PULSE INTERVALS, A SYSTEM FOR DECIPHERING THE RESULTANT CIPHERED SEQUENCE OF PULSES COMPRISING A GATING CIRCUIT COMPRISING A FIRST INPUT CIRCUIT CONNECTED TO RECEIVE THE PULSES FROM THE OUTPUT OF THE CIPHERING CIRCUIT, A SECOND INPUT CIRCUIT, AN OUTPUT CIRCUIT, MEANS FOR PRODUCING AN ON PULSE IN SAID OUTPUT CIRCUIT IN RESPONSE TO AN ON PULSE IN ONE OF SAID INPUT CIRCUITS ONLY AND MEANS FOR PRODUCING AN OFF PULSE IN SAID OUTPUT CIRCUIT IN RESPONSE TO SIMULTANEOUS ON PULSES IN SAID TWO INPUT CIRCUITS, A DELAY DEVICE PRODUCING A DELAY EQUAL TO SAID PREDETERMINED INTEGRAL NUMBER OF PULSE INTERVALS AND CONNECTED TO RECEIVE PULSES FROM SAID OUTPUT CIRCUIT, AND CONNECTIONS FOR SUPPLYING THE OUTPUT OF SAID RECEIVING DELAY DEVICE TO SAID SECOND INPUT CIRCUIT.