[time-nuts] Commercial software defined radio for clock metrology

[Bruce Griffiths]

The Red Pitaya FPGA may be a little too small.Its not clear if a single chip ADC is used.If not, the performance will suffer.Dc coupled inputs will degrade the performance somewhat compared to transformer coupled inputs.

Input bandwidth would be around 40MHz or so for the Nyquist band of interest.The output bandwidth used was something like 100 kHz.
Bruce
 

    On Saturday, 28 May 2016 2:01 PM, Hal Murray <hmurray at megapathdsl.net> wrote:
 

 
bruce.griffiths at xtra.co.nz said:
> All the filtering and down mixing is done in the digital domain.
> Anitialiasing filters in front of the ADCs are also be required. 

What sort of bandwidth is expected?

The usual trick with audio ADCs is to have a low cost analog filter that 
does't have a sharp corner but lets everything you want through, sample at a 
high rate - say 16x, run that through a digital filter with a sharp cutoff, 
then decimate down to the desired sample rate.

-- 
These are my opinions.  I hate spam.



_______________________________________________
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.