[time-nuts] AM/PM conversion on mixer, DMTD

[Mattia Rizzi]

Hello!
I just started a new job with a project involving laser synchronization.
The idea of my colleague is to use basically DMTD as a phase detector (RF 3
GHz, IF=10..20MHz), and then digitize the IF with ADCs.
He is very worried about AM/PM conversion (he's looking for something like
0.1degree/dB at 3 GHz), and he told me that the best results were with high
LO level mixers (he was testing double balanced mixers eval boards, I think
from minicircuit).
I had a look at the literature and I found a paper [1] that put an
upperbound between AM/PM and OIP3. Therefore I am looking for triple
balanced mixers or DBM with high IP3.
My question is: in your experience is that all or there's something else?

Thanks!

[1] M. J. W. Rodwell, D. M. Bloom and K. J. Weingarten, "Subpicosecond
laser timing stabilization," in *IEEE Journal of Quantum Electronics*, vol.
25, no. 4, pp. 817-827, April 1989, doi: 10.1109/3.17346.