[time-nuts] Phase Detectors/Mixers for DMTD and PN measurements

[Gerhard Hoffmann]

Am 12.12.19 um 07:19 schrieb Bruce Griffiths:
> Cross Correlation methods are commonly used with analog mixers.
> Most of the high end commercial offerings use it (Holzworth, Anapico, Rhohde & Schwarz, etc.)


"High End"  is a contradiction to "Commonly Used" somehow.


In the published timenuts world, aka NIST or the usual suspects, there 
is only

deafening silence. I have seen the marketing blurbs and have even 
limited access

to the really good stuff.


Yes, there is the all-digital solution of Andrew Holme based on a

Spartan-6 demo board, some ADCs and Verilog but that's it. (And I like it!)


In the published analog area, there is pure joy when a 2N2222 mixer pushes

the state of the art a few dB at 5 MHz.


While I'm at it, is there a _tested_ open C/C++/Fortran/whatever 
implementation of

fft/xcorr that I could cut & paste into a BeagleBone black?


Gerhard, DK4XP