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 - GitHub - kit-cel/gr-drm: DRM transmitter using GNU Radio
Stereo Tool (FM processor) - Download Stereo Tool
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.