Why has digital radio taken so long to happen?

When we ask CEO of Commercial Radio Australia, Joan Warner, why digital radio has taken so long to get here, she actually responds that the process has been relatively quick.

“We’ve been working on this directly since 2003,” she says. “It’s not as simple as saying let’s do a new tech and then rolling it out.”

Warner explains that it’s important to Australia’s radio broadcasters that every possible standard and technology be examined and rated for suitability. There are also many behind-the-scenes questions that needed to be answered: who would control the transmission system? Would existing broadcasters get exclusive access to the new tech, and for how long?

And because the airwaves are public property, big decisions such as adding digital radio to the existing radio landscape have to be backed up by government legislation.

It’s hardly a glamorous start for a new tech: locked in committee rooms full of overhead projectors and whiteboards.

Still, all that’s behind us now, and it’s time to get the ball rolling on digital radio. But what exactly is digital radio?

Why we need digital radio

Current AM and FM broadcasts are analog. Your receiver converts the electrical signal directly into audio. You might have a radio that provides some kind of audio filtering or processing, but the signal is intrinsically degraded by the transmission process.

AM and FM suffer from all sorts of disadvantages. They take up a lot of bandwidth, so the number of channels that can be carried is limited. They’re vulnerable to ‘crosstalk’ – with stations overlapping each other. And of course we’ve all experienced static and loss of signal.

In fact, there are many similarities between the digital radio experience and digital television. Digital radio gives a solid signal, without any fuzz or static. You’ll also tune in to ‘named’ stations instead of esoteric numbers like 106.5 or 88.1 – just select ‘ABC Radio National’ from a list on your receiver.

The standard for digital radio – in Australia it’s called DAB+ – specifies that receivers must have a two-line text display. But this isn’t just for station names. Broadcasters can also add metadata to their transmissions, including playlist information, weather reports, anything really.

“Hearing is believing with digital radio,” says Warner. “Listeners are going to be really excited once they get the opportunity to actually experience digital.”

She says that with the ability to show text, and even images, digital radio has a natural “wow factor” built in. It will dramatically refresh our oldest and perhaps most undervalued broadcast medium.

In the beginning – a short history of digital radio

The Digital Audio Broadcasting standard, DAB, was developed in 1988 and formalised in 1993. Continental Europe and the UK started broadcasting in 2000, and it’s estimated that by 2006 around 500 million people lived in coverage areas for digital radio.

But the history of DAB is somewhat chequered, and that’s why we won’t be using it here in Australia. Instead, we’ll use the upgraded DAB+ standard. So what’s the difference?