US terrestrial radio groups have joined forces to defend their collective patches against the steady advances of satellite rivals.

The HD Digital Radio Alliance, which comprises seven of the nation's largest radio broadcasters including Clear Channel and Infinity, is bidding to accelerate the rollout of high-definition radio, a technology that many observers see as the key to the future of non-satellite radio.

HD technology allows radio stations to use their allotted frequency more efficiently, so they can broadcast on multiple channels. It will also improve sound quality.

Alliance president Peter Ferrara says one of its top priorities will be to convince automakers to install digital receivers in their vehicles. Satellite broadcasters have already achieved such distribution deals. The alliance also wants to win lower receiver prices from retailers.

Adds Ferrara: "Nothing could be more important than HD radio becoming standard equipment in the auto industry."

Data sourced from Financial Times Online; additional content by WARC staff