[Discuss-gnuradio] Resampling, filters, and CPU Usage.

[Jordan Johnson]

As most of you likely have seen, I've been working on a flowhraph for quite some time. Using gr-drm and an external FM processor, I have made a sort of open alternative to HD Radio...because fun.

Anyway, the DRM signals are sampled at 48khz and the FM portion at 192. The remainder of the graph is 384k due to filters. 2 bandpass filters,  4 band reject filters.

To help you help me, I have uploaded the flow graph to Google Drive. It require gr-drm and for your audio to be set to Jack. (Or just use null sinks).I'm still rather new to GNURadio so....I'm sure there's some rookie mistakes in there: 

IBOC.grc - https://drive.google.com/file/d/0B9lYGe4c92PnTDlVbkprVFRybnM/edit?usp=sharing

gr-drm - https://github.com/kit-cel/gr-drm

Stereo Tool (FM processor) - http://www.stereotool.com/download/

So, what is it supposed to do?

Two DRM signals are to sit on the outside of the FM envelope. There should only be two, but as they are interpolated, they make a mess and that's why I put the filters there.