What is two-way radio traffic?

The term two-way radio traffic stands for a technology that makes it possible for individuals to keep in touch with each other by using radio waves. Each user has a radio that can both transmit and receive audio and data transmitted over the aforementioned radio waves.

A two-way radio system can be very simple, for example when two radios are directly connected to each other, and very complex, when an encrypted network covers an entire country.

You may be familiar with two-way radio from the term ''walkie talkie'', a term often used to refer to unlicensed radio devices. The term two-way radio covers both unlicensed and licensed equipment.

Below you will find a number of examples of frequently asked questions about two-way radio traffic.

Two-way radio traffic converts audio waves into radio waves that are then sent through the air. These waves are then picked up by other radios that convert the radio waves back into audio.

The radio waves can be transmitted as an analog as well as a digital signal, with digital transmission being the more modern technology. With digital radio it is possible to transmit other types of data by means of radio waves. Think of, for example, text messages and status updates.

It is even possible to encrypt data when using digital radio. This prevents others from using your network without permission.

Two-way radio traffic takes place between frequencies of 30 MHz (Megahertz) and 1000 MHz, better known as 1 GHz (Gigahertz). This range of two-sided frequencies is divided into two categories.

1. Very High Frequency (VHF) - Range between 30 MHz and 300 MHz
2. Ultra High Frequency (UHF) - Range between 300 MHz and 1 GHz

Within this radius, most two-way radio traffic falls in the 136 - 174 MHz and 403 - 527 MHz parts of the spectrum, both of which require a license.

Each country has its own organization that issues these licenses, but some two-way radio frequencies are license-free (for example, the PMR446 at 446 MHz).

This depends on what type of system you need. If you need a small amount of radios in a remote location with a small coverage area, you may get away with using unlicensed radios (such as the aforementioned PMR446).

If you need a larger coverage area, require secure communication, have multiple teams communicate independently, or operate from a built-up area such as a city center, you will need to purchase licensed equipment. At Firecom we can of course help you with this.

Yes and no; some functionalities are common to all manufacturers as they are defined by radio standards such as DMR (see: What is DMR?).

While standard functionality will almost always work between different systems (such as sending and receiving voice messages) you may want to take advantage of features that are outside the scope defined by the standards.

So, before deciding what equipment to buy to further expand your system, it is important to consider what features you are already using and whether they are unique to the type of equipment you are currently using.

If these are not unique, it is useful to check with the manufacturer whether interoperability tests have been performed between your current and intended equipment.

The answer to this question depends mainly on the equipment you have and the infrastructure installed around it. The International Space Station, for example, orbits the Earth at a distance of 408km and uses DMR to communicate with Earth. There are few obstructions between the station and the antennas placed on the ground, making the signal easy to receive.

For comparison: an unlicensed radio can work well within a building for as little as 100m.

Infrastructure can be installed in the coverage area to extend the range of two-way radio systems. This limits the range of the system only by the amount of equipment you can afford to install.

Two-way radio repeaters can spread signals over a large area and be connected to each other through other connections such as the internet to create coverage in specific areas.

Many two-sided radio models have a GPS function that can report the position of the radio to, for example, an emergency room. This location functionality can always be turned on or turned on in specific situations, such as when a user presses the emergency button.