Re: [Discuss-gnuradio] saturation with multi_fft.py

[Eric Blossom]

On Tue, Oct 09, 2007 at 03:02:33PM -0400, address@hidden wrote:
> Thanks so much for clarifying that!  I see now that config.vh controls how 
> the code is configured.


FYI, I've committed new rbfs to the trunk.  They were built with
Quartus II Web Edition, version 7.1 SP1


> Regarding the loss of the half-band filters in the multi-antenna fpga 
> configuration; what is the recommendation to avoid aliasing?  Say for the 
> case of a 2 MHz carrier AM waveform with modulation out to 100 kHz.  What 
> kind of filtering would I need to avoid aliasing?
> 
> thanks again,
> eric

With the halfbands, it's flat to about 70% of the passband.
decim = 320 gives 200kS/s complex baseband, a bit more than you'll
need. 


Without the halfbands, I'd use about 4x the bandwidth of interest,
then filter and decimate in the host for the final channel selection.
In your case, I'd use decim = 160 giving 400kS/s.

Eric