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Time synchronization apparatus and a method thereof using a global positioning system of a satellite

  • US 5,757,786 A
  • Filed: 12/27/1994
  • Issued: 05/26/1998
  • Est. Priority Date: 12/27/1993
  • Status: Expired due to Fees
First Claim
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1. A time synchronization apparatus using a global positioning system of a satellite receiving a 1 pps signal from the satellite, comprising:

  • an oscillator for generating an oscillating frequency signal compatible with a global positioning system of a satellite;

    a counter for generating an internal 1 pps by counting the oscillating frequency of the oscillator;

    a comparator for outputting a phase difference signal by comparing a phase of the 1 pps signal received by the global positioning system and the internal 1 pps outputted from the counter;

    a first controller for phase correcting the internal 1 pps outputted from the counter based on said phase difference signal;

    a second controller for correcting the phase difference between the output frequency of the first controller and the oscillating frequency signal; and

    a microprocessor for providing the phase difference signal outputted from the comparator to the first and second controllers for phase difference corrections, and for outputting a frequency error value to the oscillator for correcting the frequency of the oscillating frequency signal on the basis of the GPS 1 pps signal.

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