Re: [Discuss-gnuradio] multi-band receiver

[Dan Halperin]

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Johnathan Corgan wrote:
> For the receive side, you can use a blks.analysis_filterbank to turn a
> wideband signal with N carriers into N baseband channels equally spaced.
> 
> Then you can attach demodulators to these output ports.
> 
> This is demonstrated in the gr-pager code:
> 
> http://gnuradio.org/trac/browser/gnuradio/trunk/gr-pager/src/usrp_flex_band.py
> 
> Here we capture 1 MHz of USRP spectrum, then create 40 baseband output
> channels at 25 KHz each, then attach 40 decoder blocks to these outputs.

In this example (and indeed, in the code for the analysis_filterbank),
we divide a 1MHz band exactly into 25 kHz channels. However, the
channels at the edge will be attenuated (cite: Matt's email of yesterday
12:11 AM PST). I therefore oversampled the desired passband by 33%,
which causes the resulting wideband signal to not divide evenly into
channel-sized chunks.

If I do some sort of 3/4 resampling should the passband quality suffer?

Thanks!

Dan
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