Radio is an electromagnetic wave, too slight to effect people but enough to generate currents in metal aerials that can be converted into sound. The principle was discovered in 1820, but we had to wait until 1920 for the first broadcasting stations to appear.
Digital radio enhances the old analogue radio technology by encoding the signal into discrete pulses. It provides cleaner reception and allows more channels to be crowded into congested wavelengths. There are several different formats in use, but in the UK one called DAB has been widely adopted.
Digital stations can be received on DAB radios, across the internet, down cables, or on Sky and Freeview-enabled televisions.
Why Don’t Radio Waves Get Mixed Up?
Analogue signals do – that was the problem. Digital transmissions can be sorted by logic circuits, just as signals on the internet are. They can also be compressed (like MP3 files), delivering high quality in small packets. A single signal can even carry numerous programs bundled together (multiplexing).
Radio waves travel at the speed of light, but digitising, compressing, decompressing and converting to sound adds delay even to a “live” broadcast.
Whether digitized or not, receiving radio still usually depends on aerials. Even digital stations that send their signals across the internet often rely on aerials, because the internet does – travelling between Wi-Fi masts or being relayed by satellites.
The aerials and receivers needed for digital radio, like those for digital TV, are complicated to set up, and to receive different types of radio you may need carefully designed aerials, especially if you aren’t close to a transmitter.
As the range of radio equipment has grown more complex, the help of professional installers has become more valuable. For example, if you live near Worcester TV aerial repair, installation or advice is available from http://steveunettaerials.co.uk/services/tv-aerials-repair-installation-worcester/.
Future of Radio
In November 2006 the WorldDMB announced in that DAB would be adopting new standards. The update has been called DAB+. Some people with older DAB radios may need firmware updates or new equipment (see https://media.info/radio/opinion/dab-and-dab-the-differences-and-its-use-in-the-uk).
More than half the population are believed to tune in to digital radio at least once per week, especially in their car. Digitization means that channels do not drift and fade as vehicles move along. With the upsurge in mobile devices, digital radio has an assured future for years to come.