Alf Jacob Munthe wrote:
Is something similar coming stateside?

Kinda, sortagrin.

The USA is deploying something called "In Band On Channel" (IBOC), or
"HD Radio". This scheme allows stations to broadcast a digital signal
over the same frequency as their analog broadcasts. (more accurately,
for FM stations the digital signal is broadcast in the "guard band" at
the outer edge of the analog FM signal; for AM/MW stations it's
broadcast in the four channels adjacent to the analog signal. For that
reason, many call it "In Band Adjacent Channel"/IBAC!) Yes, the U.S. is
trying to do digital radio on MW.

All U.S. analog stations are authorized to begin IBOC digital
broadcasts; they need only notify the government upon turning on the
digital transmitter. There are a few (30-40?) FM stations known to be
operating digitally, and maybe a dozen MW stations. MW stations,
however, are only allowed to operate their digital transmitters during
the daytime. There are fears (justified, IMHO) that nighttime MW
digital will cause ruinous interference to existing analog MW reception.

There is one IBOC test station operating, on MW, in Mexico City. To my
knowledge it's the ONLY IBOC station outside the United States. Even
Canada has gone with the European Eureka system. [0] It is widely
believed that the U.S. has gone with IBOC for strictly political reasons
- owners of powerful analog stations are unwilling to face additional
competition from low-powered analog stations that suddenly acquire
citywide coverage areas on Eureka multiplexes, and from formerly-MW
stations that suddenly acquire high-fidelity digital sound.

The ability to receive a single program during a long trip in the U.S.
will probably never happen via terrestrial radio. [1] A U.S.
broadcasting license conveys authority for only a single transmitter,
and until recently it was illegal for one company to own enough
transmitters to cover the entire country. (or even half of it) For
that reason, while I've logged over 1,200 FM stations here, I've *never*
seen one using the RDS "alternate frequencies" function! Some U.S.
receivers do support using the "PTY" function to find some other station
airing the same *type* of programming though not necessarily the same
program. But RDS itself is relatively rare in the U.S..
--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com

[0] Four stations in Windsor, Ontario, Canada have requested government
permission to use both Eureka *and* IBOC. Windsor is located just
across a river from Detroit, USA and stations there cannot be
economically competitive without reaching a large audience in the U.S..

Unfortunately DAB is seeing little financial success in Canada.

[1] It is already possible via satellite radio. There are two services
- XM and Sirius - which provide nationwide coverage via satellite direct
to cars/homes. Both recently obtained permission to install low-powered
terrestrial repeater stations to ensure reliable coverage in central
city areas where tall buildings sometimes shield listeners from the
satellites.