While Sirius and XM battle each other for subscribers, they’re about to face another digital radio competitor, HD Radio. Formerly known as In Band On Channel (IBOC), this terrestrial digital radio system is being developed and tested right now by iBiquity.
In the first quarter of this year, over 100 stations in 40 markets are testing the system. Its benefit is that it uses the existing AM and FM radio bands but adds digital transmission capability. Digital transmission not only improves music quality, but it allows for the transmission of station information, song/artist information, news and traffic reports and other data. The result is CD-quality music and talk radio in your local area.
The HD Radio system simply widens the bandwidth of the assigned AM and FM channels, permitting digital signals to be broadcast using orthogonal frequency division multiplexing (OFDM) with multilevel modulation (i.e. QAM) schemes. The older AM and FM transmissions will continue as usual, so those without HD Radios can still get the local stations.
Just how HD Radio services will impact the satellite systems remains to be seen. Obviously, one choice will be a combination radio that gets all of the digital radio services. Other combinations are sure to make themselves known in time. The software-defined radio has arrived just in time to deal with this complexity. With such a cornucopia of radio, you may never want to leave the car.