Does anyone have an automatic Audio IQ Balancer that works for multiple frequencies for GnuRadio?

Hi All,

I want to help my students fix an annual problem we have because our QSD SDR hardware designs can never get good enough image rejection.  I want to do that by adding a GnuRadio flowgraph that uses some kind of LMS or other automatic algorithm (with more than two parameters) to automatically balance the I and Q signals.  My students are designing QSD SDR radios that downconvert HF signals to audio for a sound card to digitize often using a Tayloe mixer.  I want something like this:  

My problem with the above flowgraph is that it only optimizes the phase and amplitude at one frequency.  I want it to optimize over the whole IF, so there are no glaring images in our spectragrams.  I have seen a number of papers on doing this, but I'm looking for a quick GnuRadio solution I can put between the soundcard and Quisk.  Does anyone have something like this we could try?

Thanks,

Rob

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Rob Frohne, PhD PE

School of Engineering

Walla Walla University

100 SW 4th St

College Place, WA 99324

(509) 527-2075