NRSC-5 HD Digital Radio
RSC-5-C is the standard for digital terrestial radio in the United States.
$ nrsc5 -p 63 -g 490 -w output1071 107.1 0
$ nrsc5 -r output1071 0
$ nrsc5 -o - -f adts 90.5 0 | mplayer -
GNURadio code on Github: gr-nrsc5
The goal of this project is to implement an HD Radio receiver and transmitter in GNU Radio. HD Radio is standardized in NRSC-5. The latest version of the standard is NRSC-5-D, which can be found at http://www.nrscstandards.org/NRSC-5-D.asp.
So far only a transmitter has been implemented. A stand-alone receiver for RTL-SDR is available here: https://github.com/theori-io/nrsc5/