[time-nuts] TIC resolution impact on GPSDO's performance

[Dr Bruce Griffiths]

Magnus

Amended to substitute plesiochronous and plesiochronism for the 
incorrect words I used previously.

As the frequency of the clock which controls the timing of the receiver 
PPS pulse output drifts and approaches plesiochronism with the 
"true" frequency of the PPS signal, the rate of change of the PPS timing 
error due to quantisation decreases reaching zero should the clock 
achieve synchronism with the "true" PPS frequency.
Thus hanging bridges occur when the clock frequency approaches 
plesiochronism with the "true" PPS signal frequency and then drifts 
away from plesiochronism with the PPS signal..

When the frequency of the clock controlling the timing of the receiver 
PPS pulse output is synchronous with the PPS frequency, then neither 
sawtooth corrections or hanging bridges occur, however there may be a 
fixed offset of up to 1/2 a clock cycle between the "correct" and the 
actual leading edge of the receiver PPS output pulse.

Please correct and simplify these statements as required.

The only problem that I can see is we still need to define how close to 
synchronism the timing clock frequency and the "true" PPS signal 
frequency system must be to be considered plesiochronous.

Bruce