Radio stations are free to launch a competitive alternative to satellite
radio thanks to the Federal Communications Commission's decision Thursday to
approve in-band, on-channel (IBOC) technology that will make CD-quality sound an option
The new technology -- which requires listeners to buy new radios equipped with
digital receivers -- allows stations to introduce a digital signal simultaneously
and on the same frequency as their analog signals. IBOC for FM is approved for
around-the-clock use and during daytime only for AM.
So far, IBOC AM does not work at night because of "skywave," a near-vertical
wave created when radio signals from 50-kilowatt AM clear-channel radio
stations bounce off the stratosphere.
The prevailing IBOC technology is controlled by iBiquity Digital Corp., a
consortium owned by ABC, Clear Channel Worldwide, Viacom Inc., Harris Corp., Lucent
Technologies and Texas Instruments Inc.
Although the FCC aims to phase out analog signals eventually, there is no
time frame for switching off the old signals. The pace of the rollout and
additional standards necessary for new services such as second audio feeds and
audio-on-demand will be the subject of a later rulemaking.