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 mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
