The British communications ministry drew a map this summer for moving the nation from analog FM radio to the digital audio broadcasting (DAB) standard by the end of 2015. Skeptics say that the move will waste money and that consumers aren’t interested. Conversion will require hundreds of new transmitters. And while it may be interesting culturally, the freed-up spectrum will be of little monetary value to the government.
DAB is one of a half dozen digital broadcast standards found around the globe. It works by converting analog sound—the voice in the microphone—to a compressed digital signal. In Britain, the digital channels reside between 217.5 and 230 megahertz, on VHF band III.
When the digital signal leaves the transmitter, it is in chronologically coded fragments—a mixture of broadcast and metadata—over that wide band. It’s sort of the way Mike Teavee was split up into bits on his journey from the camera to the television in Roald Dahl’s Charlie and the Chocolate Factory. The digital radio transmitter also sends each fragment multiple times in order to increase the chances of the signal getting through. DAB receivers are equipped with a chip set that receives the data stream coming in from the transmitter, decodes it, and then assembles the data in the correct order.
The June ministerial pronouncement, the Digital Britain report, was met with howling from DAB critics. Many of them jumped the gun by thinking the move to digital by 2015 was mandatory; it is not. But DAB skeptics have more basic objections as well, which come down to waste and lack of consumer demand.
The cost here doesn’t really hit the consumer. Basic DAB radios can be had for US $40 or less. They’ll get cheaper, and soon enough, in all likelihood, they will come standard inside cars and mobile phones. The cost is much more in the build-out of the infrastructure, which will mean many new transmitters; Eureca Research analyst Gareth Owen hears the number may be anything from 120 to 700. And at the end of all that build-out, UK residents can throw their 130 million analog radios in the garbage.
Owen does expect the UK to move to digital radio, just not by 2015. Digital Britain makes clear that migration criteria first require half of UK listeners to be tuning in on digital. National DAB coverage must also be comparable to FM coverage, with local DAB reaching 90 percent of the population and all major roads.
The UK government will create incentives for transmitter operators to extend digital coverage. Consumers are already coming home with DAB-compatible radios to replace their old ones, and Owen expects the same thing will happen on the broadcast side: Old transmitters will be replaced by DAB-compatible hardware.
But unlike the recent U.S. transition to digital TV, which resulted in a $20 billion auction of the 700 MHz spectrum, the FM space in Britain is not a cash cow. The frequencies aren’t useful for deep-pocketed firms like mobile telcos. Instead, they’ll go to very local (and likely very cash-strapped) broadcasters.
So with no cash incentive for the government, there’s no hard deadline to get this done. Analysts say that if it takes too long, Internet radio delivered via Wi-Fi and other wireless schemes will haunt DAB. Still, Internet radio over wireless networks will have its own issues, such as broadcasting rights and bandwidth fees. Don’t expect any of this to be as cheap or as simple as tuning in the old FM.
Fans of digital radio can look to Paris for inspiration: The French government earlier this year said it will require cars to be fitted with digital radio receivers. Every radio in the country must be capable of receiving digital signals by 2013. Other corners of the continent—Germany’s just rejected new funding for digital migration to DAB—show that there’s a long way to go.
Stateside, you may (or may not) know that there are some 2000 stations already able to broadcast using the HD digital standard. Insignia has just released a portable HD player for $50. Reviews? Not so good. And Washington likely has enough on its plate now to keep it from worrying about adding a digital radio mandate to the mix.
About the Author
Michael Dumiak covers technology from Berlin. In IEEE Spectrum’s May 2009 issue, he described a project that followed the trail of data thieves using online traps called honeypots.