Fiber Length Stabilization/Phase-Frequency Metrology/Control

rjo

QUARTIQ has released the fls application for Stabilizer.

The application supports various tasks of receiving an RF input signal and processing its phase and frequency. The result of the processing can be be used to affect the phase and frequency of an RF output signal.
The application controlled and monitored via network using MQTT. It emits telemetry data as well as high-rate streaming data for external processing and analysis.

See https://github.com/quartiq/stabilizer/pull/1032 and
https://quartiq.de/stabilizer/firmware/fls/index.html for some data and docs.

awallin

This looks interesting!
We have some fiber-links with e.g. an AOM drive-frequency of 178 MHz and the double-pass beatnote at 2x178 = 356 MHz. Would the Pounder AFE support this also?

Is it possible to run a Stabilizer+Pounder standalone in a rack, with only PoE for power+data, and a reference-clock (10MHz?) input?

regards,
Anders

Guest

I am also wondering if the Pounder analog mixer can mix down to a non-zero IF (maybe 1 kHz or 10 kHz) that is then digitized by the stabilizer.
This should allow for frequency counting of the 1-10 kHz IF by the stabilizer, so that we can validate (and log data continuously) that the fiber link is locked and has no unknown frequency offset?

rjo

Guest non-zero IF

You may want to click on the links.

rjo

The AD9959 PLL does 4-20x limiting your ref clock options.
The RF inputs have a 160 MHz lowpass as do the LOs and RF outputs.
It runs on PoE + Ethernet + refclock.
You could use Stabilizer+Urukul-AD9912 (also just Ethernet+PoE+refclk) to make 10->100 MHz for a bunch of Stabilizer+Pounder combos... https://quartiq.de/stabilizer/firmware/dds/index.html