Digital audio broadcasting: US technologies and systems, terrestrial and satellite

The world of audio has gone digital. Listeners are demanding the same compact disk ("CD") quality music wherever they go-witness the widespread availability and use of battery operated CD players. Over-the-air broadcasting has yet to participate in this digital revolution. The United States has taken the lead in the development of inband, on-channel ("IBOC") and in-band, adjacent-channel ("IBAC") technologies which will allow existing broadcasters to deliver CD-quality music with the areas they currently serve without additional frequency allocations. Further, the US has initiated licensing of satellite and complementary digital audio radio systems ("DARS") in the 2310-2360 MHz band.