Paper presented at the 47th Annual Precise Time and Time Interval Systems and Applications Meeting
Monterey, California, January 25-28, 2016


A Precision Time-Frequency Estimator (PTFE) method for measuring clock time and frequency differences among multiple distributed devices connected by conventional low-bandwidth interfaces is proposed. The clocks being compared may have different frequencies. Picosecond-level timing accuracy is achieved by tracking the phase of a beat signal created by digitally mixing the two clock signals. Clock cycle ambiguity is resolved by using reference event pulses from the two clocks to relate the beat signal phase to the reference event pulses. The PTFE implementation requires minimal hardware resources and pairs of PTFE instantiations may be used to determine cable delays for synchronization between distributed devices. The performance of the proposed approach is demonstrated with results from laboratory testing.…Read more

Posted by Rockwell Collins