Hi all
Is there information anywhere about the performance on the USRP
decimation filter?
I have a setup with an external radio which has a bandwidth of 5MHz
around a 10.7MHz IF. I think the attenuation of the radio is quite poor
relatively far away from the 10.7MHz centre (e.g. -20dB at +/-10MHz).
If I use the USRP with a decimation of 8, I should get a bandwidth of
8MHz (minus the filter roll-off) I assume - is this correct?
If so, then I’m worried about images in my passband - i.e a signal at,
say, 18.7MHz will wrap around and be right in the centre of my passband,
but attenuated by 20dB by the radio itself. I assume there is
attenuation from the decimation process (the CIC/half band filter) - can
anyone give me an idea of how much decimation I can expect outside of my
passband? (or put me right if I’m completely wrong with all of this!)
Thanks for your help
Rich