How Analog Radio Works, What’s Digital Radio, and What’s Next?
In 2017, Norway is set to be the first country to completely shut down FM radio. The rest of the world won’t be far behind.
While its fate is decided in Norway, that doesn’t mean we’ll be without our trusty AM/FM companion. Radio, as a means to consume music, news and all sorts of random information isn’t going anywhere, but it is about to undergo a monumental change, and this change brings with it a promise of better signal quality and increased options for consumers in terms of programming.
How Analog Radio Works
In order to get to where we need to go, it’s important to understand where we’re at and why it’s necessary to make the change in the first place.
Terrestrial radio obviously isn’t a new technology, but instead it is one that pre-dates the 1900s. Guglielmo Marconi is credited with the first successful application of wireless technology after sending out the first radio signal – consisting of a single letter, “S” – in 1895.
Modern radio was later patented by Nikola Tesla in 1943 leading to modern use of terrestrial radio as we know it today. And in all honesty, not much has changed from Tesla’s first “modern” radio. In fact, a lot of the vintage stuff is still being used today.
The technology itself is remarkably simple. Terrestrial radio has two main parts, a receiver and a transmitter. The transmitter sends radio waves – called continuous sine waves – using one of two types of modulation. These two types of modulation are AM (Amplitude Modulation) or FM (Frequency Modulation). The main differences between the two is the frequency range (800MHz for FM or 49MHz for AM), the total number of frequencies, and the transmitter power.
The receiver exists to capture these sine waves and make playback possible.
Why Analog Radio is Being Replaced
Much like the digital switch that occurred in recent years for television, radio in an analog format is simply starting to show its age (check out these old time radio shows). That’s not to say it doesn’t work, but digital radio offers a cleaner signal, less signal degradation from devices on the same spectrum. Which is why it’s inevitable we’ll make the switch at some point. Countries like Norway are already leading the way.
Digital radio features things that analog could never offer, such as:
- More channels and content offerings
- Higher bitrate audio
- Ability to pause and rewind live radio
- The ability to easily tune by searching for station names rather than frequencies
- Enhanced experience, such as phone numbers or websites that correspond with ads, album art, and news or concert information about the band currently playing
In short, we’ve created a better mousetrap.
In fact, your radio or receiver may already be equipped for digital radio. In the US, you’ve probably heard it called by a different name, HD Radio. In Europe, it’s commonly known as DAB (digital audio broadcast). Each of these formats is remarkably close to the exact same thing, but each country is still selecting their preferred standard.
How Does Digital Radio Work?
Like terrestrial radio, digital radio sends a signal through the air that a receiver captures, and plays through your speakers.The main difference between the two is that digital doesn’t send complete information all at once. Instead, it compresses the audio and transmits it from an antenna in pieces.
The receiver then captures these pieces (much like it would on an analog signal) but instead of playing them, it decodes the encoded audio, and pieces together the audio before playing it on your speakers. While this seems like an odd process, it’s actually beneficial because the digital signal is broadcasted redundantly to improve playback.
While an analog signal can travel more distance, it is more prone to signal degradation from competing sources. Basically, this means that the static, hisses, and missed bits of information were pieces of the signal that were lost during transmission. Digital radio doesn’t have this problem.
There are two reasons the signal is better in digital.
- Receivers have advanced amplifiers which help to filter out competing signals.
- The information is sent redundantly, so even if bits and pieces are lost, the receiver is often able to formulate a sort of back-up plan by pulling from one of the redundancies before playback.
As I mentioned above, it can’t travel as far as analog. The other problem with digital is the lag caused by transmitting the audio signal in pieces, and then re-constructing them before playback. If you have a digital radio, put it next to an analog radio and tune them to the same station. You’ll notice a significant lag in the digital version.
Additionally, it can’t be retrofit to existing devices. So you’d need to upgrade your receiver, car stereo, or in-home boombox in order to take full advantage of digital. Luckily, there are tuners and adapters that are currently available if you want to avoid the expense of a full upgrade.
So, When Will Analog Radio Die?
There’s really no confirmed dates in most places (apart from Norway). While Norway will undoubtedly get the wheels turning, it’s not going to be a transition that came about as quickly as the switch to digital television. Instead, we’ll see sporadic deployment of digital test markets (or countries) while we continue to enjoy our trusty analog signal.
Many countries are already experimenting with digital radio, but haven’t made plans to completely replace analog just yet. Denmark, France, Australia, China, Belgium, Malaysia, South Africa and The United Kingdom are just a few of the many countries where you can currently enjoy digital radio.
The United States has a sort of “wait and see” attitude regarding complete roll-out of digital-only HD Radio. While HD Radio currently exists, it’s nothing more than a simulcast of the analog signal that is offered in digital. Instead of forcing the issue, the FCC (Federal Communications Commission) has decided to leave it to the stations themselves to determine when they should go fully digital.
“FM and AM radio will still be operational ten years from now… Five-year licenses for new AM and FM radio stations, which are three or four years away from launching, are still being offered.”-Radio Today’s Roy Martin
The US government, while not forcing stations to change, has offered to subsidize the changeover and is urging current broadcasters to “..commence trials of digital radio in regional areas so technical and other issues can be resolved.”
So for the time being, it appears that analog radio will exist at least a few more years in Europe, and it could be close to a decade in the United States.
Is digital radio (DAB, DMR, HD Radio, DAT+, etc.) offered where you live? What do you think the biggest hurdle is for widespread rollout and adoption?
Image credit: Vintage Fuji Radio by Joe Haupt via Flickr
Source: www.makeuseof.com
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