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[Discuss-gnuradio] Channelizing
From: |
Marcus D. Leech |
Subject: |
[Discuss-gnuradio] Channelizing |
Date: |
Thu, 23 Jun 2011 23:32:13 -0400 |
User-agent: |
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.15) Gecko/20101027 Fedora/3.0.10-1.fc12 Thunderbird/3.0.10 |
I'm working on a multi-channel radiometer, based on USRP2 with the
dual-DDC feature.
I'm trying to come up with channelizing structure that won't overwhelm
my CPU--I'm using
a 6-core Phenom II 1055T, with 4GB of 1333MHz memory.
I need to be able to carve-off 4 channels, with widths between 100KHz
and 500Khz, anywhere within
25MHz of the center frequency.
I've tried a single 25MHz input channel, then carving it up with 4 FIR
filters. That produces massive
'O', no matter how sloppy I make the channel filters.
I've tried a pair of 12.5MHz channels (using the dual-DDC feature that's
relatively new). That produces
massive 'O'.
Since ultimately, I'm mostly interesting in channel power estimates, I
might just FFT it, and pick off
the bin(s) that correspond to my channels.
Is one or two polyphase filter banks going to be cheaper? And how do I
compute the taps? There
doesn't appear to be a helper function for that in GRC :-(
--
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org
- [Discuss-gnuradio] Channelizing,
Marcus D. Leech <=