Frequency locking.

Poul-Henning Kamp
Revision 2003-03-07

It works!

These are some plots are from a trial run where I tried to measure the location of the 3rd zero crossing of the 7499M signal as precisly as I could.

In order to know what I measure, I used my HP5061A Cesium frequency standard as time-base, it has a frequency offset in the 2e-12 range and I was very interested in seeing if I could confirm this with the LORAN-C signal.

This is the time series, the downward slope corresponds to appros 1.6e-12 so that is within the possible. The noise is wors than I hoped for, but considering that there is no filtering apart from the GRI integration and master code correlation I think it is actually a pretty good result.

This shows the modified Allan variance and there are no nasty surprises there.

And a FFT over the data shows no particular artifacts either.

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