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Positioning Application: What does the "Resynchronisation occurred" message mean?

  • PosApp
  • SimGEN software
  • Normally this message only occurs in a multibox configuration at power up. 
  • It can be reported by an Auxiliary unit locking, losing lock and then relocking to the incoming master synchronisation signal.
  • This happens because when units are powered up the PLL circuitry hasn't settled and loss of lock and reacquisition is common. 
    • Powering-up the Master box first and waiting 10 seconds before powering Auxiliaries will result in fewer reported instances.
  • If the error message persists and the software will not run then using the IEEE/IP string send utility see FAQ11206 and sending the SDC! command to the Aux unit should clear the condition.
  • Other occurrences of the message are caused when the 1PPS (pulse per second) sync port is used either with or without an external reference source connected:
    • If the user is providing a 1PPS sync signal without an ext ref, then the resync’s are most likely due to instability in the user supplied 1PPS which should then be checked.
    • Also the accuracy of the simulators 10.23MHz internal oscillator should be confirmed. Please refer to the appropriate annual calibration procedure for the method to align the internal frequency to an highly accurate external reference source.
    • If the user is providing a 1PPS sync with the external reference connected then the 1PPS source must be drifting with respect to this external reference.  The user should provide the same ext ref signal to the source of the 1PPS signal to ensure system synchronisation.


Product : GNSS,SimGEN,PosApp,Positioning