Digital radio: How could we live without it?

Why digital radio is better than analogue. Users who have switched to digital radio from analogue communication often wonder how they ever managed before. But what's the difference between digital and analogue? And what makes digital so great for trunked radio systems?

F5F1776.jpgDigital technology translates voice and data signals into digits, those 0's and 1's that make up binary code. Then it transfers those digits to another device and reassembles them into the original signal. Think of a digital clock: distinct, discrete numbers that tell the time.

For users, that means:

  • Better clarity: Those 0's and 1's are very precise.
  • More capacity: Digital technology can cram a lot of 0's and 1's into the space the analogue signal travels on.

Analogue technology, on the other hand, is the process of translating voice and data signals into continuous electronic pulses. For users, that means:

Richer quality: That's perfect if you're listening to Carlos Kleiber conduct the Vienna Philharmonic Orchestra's Symphony No. 5 by Beethoven. Not so great if you're trying to hear a dispatcher deliver instructions during an emergency.

So how are digital radio and analogue communications different? Here are just three examples:

Clear voice

You can hear your colleagues more clearly with digital radio technology, because the digits can be recovered  even at the very edge of your coverage area.

The electronic pulses that make up analogue technology deteriorate and get mixed with electronic noise during transmission. That makes it harder to hear clearly what your colleague is saying at the other end of the line.

Background noise

Digital radio systems can suppress noise and fading. The TETRA system from Airbus, for example, eliminates traffic noise and even the sound of sirens. This means that the dispatcher can clearly hear what the person is saying out there in the field.

Analogue communications are easily drowned out by background noise. That is why users often can’t hear each other on a conventional walkie-talkie radio.


Digital systems guarantee privacy. That's particularly important for emergency services and law enforcement agencies.

For example, TETRA's secure, over-the-air encryption exceeds the needs of most organisations. For even more security, the end-to-end encryption will keep not only the voice, but also its related signalling encrypted throughout - from one end to the other.

In contrast, it's easy for criminals and others to eavesdrop on a conventional analogue radio system. All : they really need is to buy some simple equipment over the counter at a corner shop.

That means that users of analogue communication have used mobile phones to exchange confidential information. Not only is switching to a mobile phone cumbersome, but making the same call to each of many team members wastes organisational resources and professional time.