a short writeup of our phase-meter/digital-DMTD tests with an Ettus B210 is now on researchgate: https://www.researchgate.net/publication/336825605_Software_Defined_Radio_Based_Phase_Meter_for_Frequency_Metrology
an ADEV of 2e-14 at 1s in 0.5 Hz bandwidth is fairly straightforward to achieve, for a 100MHz signal split into ch1 and ch2. There are issues with cross-talk between the channels - looking to solve that later. The raw data comes in at 1MS/s and everything works as expected when downsampling by three decades to about 1kS/s. Then ADC noise is something else (1/f ?) than white at fourier frequencies below about 1 kHz - so there isn't much 'process gain' achieved when downsampling further to 100S/s or 10 or 1 S/s. Anders _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
