System for locating the end of a sync period by using the sync pulse center as a reference

• US 3,309,463 A
• Filed: 04/25/1963
• Issued: 03/14/1967
• Est. Priority Date: 04/25/1963
• Status: Expired due to Term

• Current Assignee: Kurt Roedl
• Original Assignee: Kurt Roedl
• Inventors: Roedl, Kurt
• Application Number:
  US04/275,584
• Time in Patent Office: 1,419 Days
• US Class Current: 375/365
• CPC Class Codes: H04L 7/042 Detectors therefor, e.g. correlators, state machines digital correlators in general G06F17/15
• CPC Class Codes: H04L 7/044 using a single bit, e.g. start stop bit

Claims

1. THE METHOD OF GENERATING A SYNC PULSE WITH THE AID OF A TRAIN OF BIT SIGNALS AT LEAST ONE OF WHICH OCCURS WITHIN A SYNC PERIOD, THE CENTER OF SAID ONE BIT SIGNAL OCCURRING IN FIXED TIME RELATION WITH RESPECT TO THE NOMINAL CENTER OF SAID SYNC PERIOD, SAID METHOD COMPRISING GENERATING CLOCK PULSES OF FIXED REPETITION RATE, THEN ACCUMULATING AND COUNTING SAID PULSES AT ONE RATE DURING THE INTERVAL OF SAID ONE BIT SIGNAL, THEN ACCUMULATING AND COUNTING SAID PULSE AT ANOTHER RATE TWICE SAID ONE RATE AFTER THE TERMINATION OF SAID ONE BIT SIGNAL UNTIL A PREDETERMINED NUMBER HAS BEEN COUNTED, SAID PREDETERMINED NUMBER CORRESPONDING TO THE DURATION IN TERMS OF CLOCK PULSES OF SAID SYNC PERIOD, AND FINALLY GATING OUT SAID SYNC PULSE WHEN SAID PREDETERMINED NUMBER IS REACHED.