What does "TETRA over LTE" mean?

Published: 8 Apr 2016

TETRA over LTE? Public safety LTE? What do these things really mean?

Ask an engineer to explain what TETRA over LTE means and they may say something like: “TETRA over LTE is an LTE smart device application and an interface in the TETRA service core to connect from the smart device to TETRA services, using a secured VPN tunnel over LTE data access.”

Errr, what does that mean in everyday terms?

Well, if you use a TETRA radio, adding TETRA over LTE will make it possible for you to talk to your smartphone-carrying colleagues in a group call. Just the same as anyone else. And the colleagues in the control room can manage these users and this communication, too.

Of course it’s a little more complicated than that. Those colleagues will need the special application that allows them to communicate in TETRA groups. The TETRA and LTE networks also have to work together in a certain way.

Public safety LTE?

Another question is whether TETRA over LTE is the same as public safety LTE?

Public safety LTE is a generic term, and includes all kinds of solutions for public safety users. These solutions range from whole radio network solutions to single function applications. TETRA over LTE is a reliable and safe way to start the evolution of PMR networks. But PMR evolution is not only a question of technology. There are other things to consider when planning a smooth evolution towards the broadband future.

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Download: Hybrid networks for public safety


Back to the common questions related to TETRA and LTE…

How secure is TETRA over LTE?

To make TETRA over LTE secure, we need to control who gets the application into their smartphones and which groups they can participate in and when.

A single tool is needed that lets you manage all users, both TETRA and smartphone. This will ensure that access to groups is controlled, allowing each user to communicate in the groups they need and removing access once the task is complete. Such a tool exists: several network operators use the Tactilon Management tool for managing just this.

How could we get this into our TETRA network?

There is no point in adopting new apps and services if they need a major revamp of processes and hardware to work. You need a solution which  lets you continue to use your existing equipment and processes. The solutions must also be straightforward to implement.

How could we use this in practice?

You probably co-operate with different organisations, such as the Red Cross, security services, different voluntary organisations and many others. The people in these organisations would not need a TETRA radio but they could still easily communicate with your teams in specific talk groups.

You may also have colleagues who do not carry TETRA radios with them all the time. TETRA over LTE means that when their help and co-operation is needed, they can communicate with you in groups - using the Tactilon Agnet app.

So, you and your smartphone-carrying colleagues can communicate and work together. They can also communicate with the control room! Also from outside TETRA network coverage, provided that the broadband network is available.

If you have questions about LTE, take a look at my earlier blog post "10 LTE facts that are NOT just for nerds," and for a complete picture of the steps in the path of PMR evolution, take a look at this helpful summary from Key Touch magazine: "14 great resources to help evolve your PMR network to broadband".

Editor’s note: This post was first published in April 2016 and has since been updated for accuracy and comprehensiveness.

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The Secure Communications blog gives you insights into critical communications future, secure and critical communications, public safety and other professional apps, current events, Tetrapol and TETRA radios, and active paging, for example.