[time-nuts] LPFRS disciplining: first result

[Azelio Boriani]

At last, I'm running my first Rb disciplining algorithm. Using the
time-to-digital posted time ago, I get the difference from the M12M PPS and
the Rb 10MHz divided down PPS. The difference (that is phase) is read every
second, is sawtooth corrected, is accumulated for 100 seconds. The
difference of this difference (that is frequency) is also accumulated but
for 1000 seconds. At the end of 1000 seconds the accumulated value is
applied to the DAC as an integral action (DACIntegralnew=
DACIntegralprev+Freq1000*Ki) and the accumulated phase is applied as a
proportional action (DAC= DACIntegralnew+Phase100*Kp). Now the resulting Rb
PPS is in a 25nS window compared with the Z3815A (using an oscilloscope
with the infinite persistence, last 3 hours after 22 hours running).