[time-nuts] OT: leaching was, Alternative time interval interpolation technique

[Bruce Griffiths]

Attila Kinali wrote:
> On Sun, 15 Aug 2010 14:59:43 +1200
> Bruce Griffiths<bruce.griffiths at xtra.co.nz>  wrote:
>
>    
>> Mea Culpa.
>>
>> Below is a link to the paper using SAW filters to achieve a sub ps time
>> interval interpolator noise:
>> http://cddis.gsfc.nasa.gov/lw16/docs/papers/las_4_Prochazka_p.pdf
>>
>> And the associated presentation:
>> http://cddis.gsfc.nasa.gov/lw16/docs/presentations/las_4_Prochazka.pdf
>>      
> A quick skimming over the error analysis Panek made, suggests that
> the jitter of the clock source is the biggest contributor to measurement
> errors. But he never says how a clock source with such a low jitter is
> build. Although he references a few times a module build by Josef Kölbl
> of the Fachhochschule Deggendorf, there is no description available what
> kind of device that is.
>
> Does anyone have any pointers to recommended reading on the design of such
> low jitter oscillators?
>
> 			Attila Kinali
>
>    
Such low jitter oscillators are readily available.
With some care (bandpass filtering) a cycle to cycle jitter of around 
50fs or so is attainable with a Wenzel OCXO for example.
However the time interval jitter degrades as the time interval increases.
Achieving a cycle to cycle jitter of 1ps or so is relatively easy with a 
10MHz or 100MHz OCXO having sufficiently low phase noise.

Bruce