[Discuss-gnuradio] GSoC: Filter Design tool update

Hi all,

A brief update on the new features added to the filter design tool[1]

--IIR Filter Design (Scipy Based)

   -Butterworth

   -Elliptic

   -Chebyshev-1

   -Chebyshev-2

   -Bessel

--Pole-zero plot now supports addition, deletion of poles/zeros with conjugate support.

A small video showing some of the added features can be found here[2].

At first I started using Robert McGwier's existing code[3] and added features to that as suggested by Tom and Martin. Later finding that Scipy's filter design functions[4] are very much optimized and robust, I decided to use those. Martin also pointed out that it will just be a duplication of work and suggested me to use scipy for IIR design.

I did a basic integration of the code to gr-filter component of GNU Radio[5]. I haven't pushed icons yet to the branch. It would be really helpful if anyone can comment on the current integration, so that I can make suitable modifications.

In next few weeks I will be adding some special filters like half-band filter to the design tool, then will proceed with integration of gr_filter_design to GRC and will try to add QA tests for filter design routines wherever they are missing.

[1]https://github.com/zeroXzero/gr-filtdes

[2]http://www.youtube.com/watch?v=20ZrfUZjUUA

[3]http://gnuradio.org/cgit/n4hy.git/log/?h=n4hy_iir

[4]http://docs.scipy.org/doc/scipy/reference/signal.html

[5]https://github.com/zeroXzero/gnuradio-sreeraj Branch: filtdes_gui

 

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Regards
Sreeraj Rajendran
http://home.iitb.ac.in/~rsreeraj