RE: [Discuss-gnuradio] Demo Audio Code

[Ettus, Matt]

> http://xtrsystems.com/vlf/image/wwvb_xy - WWVB real and 
> imaginary channels plotted against each other (my personal favorite)


My favorite too!  All you need is a good pll, and you can get those cool
looking circles to look like some not-as-cool-looking-but-way-more-useful
dots.  Then you could just use a simple data slicer to get the data, and the
PLL frequency would give you your frequency info.

See src/gnu/lib/dtv/GrAtscFPLL.[cc,h] for some sample code.  You might even
be able to use it as is.  It was developed for an 8-PAM system, but will
perform even better for an ASK system since the signal is unipolar.  You may
need to tweak the gains.

Matt