A look at US radio from a British perspective:
Here are a few excerpts from a long article pertinent to this topic:
"In reaction to the onslaught of digital television, satellite radio, iPods and the Internet, good old terrestrial radio has devised a last-ditch effort to stay alive and stay dominant. In a burst of marketing genius, a consortium of broadcasting companies formed a developmental firm called iBiquity to create a new mode of broadcasting confusingly called HD Radio. Without a proper amount of RF spectrum for a new individual radio service, their plan was to squeeze (crowbar?) digital signals onto the existing broadcast bands. They call it "In Band - On Carrier" or simply IBOC."
"At night, a new kind of symphony exists. Sky wave propagation delivers signals from hundreds of miles away to your set. Consider the racket that ensues. On the east coast of The United States we have witnessed the blending of digital IBOC stations on 750, 760, 770 and 780 all at once. Not only does the noise combine; it beats due to propagation phasing causing a phenomenal noise."
http://karlzuk.blogspot.com/2008/04/state-of-states-american-broadcasting.html
Here are a few excerpts from a long article pertinent to this topic:
"In reaction to the onslaught of digital television, satellite radio, iPods and the Internet, good old terrestrial radio has devised a last-ditch effort to stay alive and stay dominant. In a burst of marketing genius, a consortium of broadcasting companies formed a developmental firm called iBiquity to create a new mode of broadcasting confusingly called HD Radio. Without a proper amount of RF spectrum for a new individual radio service, their plan was to squeeze (crowbar?) digital signals onto the existing broadcast bands. They call it "In Band - On Carrier" or simply IBOC."
"At night, a new kind of symphony exists. Sky wave propagation delivers signals from hundreds of miles away to your set. Consider the racket that ensues. On the east coast of The United States we have witnessed the blending of digital IBOC stations on 750, 760, 770 and 780 all at once. Not only does the noise combine; it beats due to propagation phasing causing a phenomenal noise."
http://karlzuk.blogspot.com/2008/04/state-of-states-american-broadcasting.html