Marcus Leech wrote: > Is there a way to produce an efficient notch filter with the bandpass > filter designer in Gnu Radio? You can use a resonating IIR filter for that. They are very efficient for building a notch or narrowband filters (single out a single frequency) The filter designers in gnuradio can not design it yet for you unfortunatly. (I am working on source which can design them.)
I do already have an optimized implementation of a resonating IIR filter. (Several of the taps are +1, -1 and 0) See: http://www.olifantasia.com/projects/gnuradio/mdvh/iir/ This filter only uses 2 multiplies to get very nice and narrow filters. ALso note that the current standard multitap IIR implementation probably has a bug, (See my mail with a fix for that in the mailinglist archive) Greetings, Martin > > I'm seeing narrowband interfering signals that are in-band (with respect > to the bulk filtering in front > of the receiver), and I want to notch one or more of them into > oblivion. I'd previously used an > FFT filter, and set zeros in the bins where I wanted notches, but it > wasn't very efficient. > > > > > ------------------------------------------------------------------------ > > _______________________________________________ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio