By Susan Layne and Thierry Sens, Strategic Industries, Alcatel-Lucent
TETRA (Terrestrial Trunked Radio) communication standard is widely used and deployed by Government, Transport and Public Safety agencies. This is mainly due to the numerous advantages TETRA provides compared to other radio systems, such as the quality of voice, the number of communication features (trunking, priority/preemption, encryption, recording, etc.) and its multi-vendor interoperability capabilities. TETRA is a perfect solution for operational voice communications. However, with the need to always improve the quality of response and the efficiency of operations, Private Mobile Radio (PMR) network users are willing to use broadband technologies. TETRA technologies cannot meet those new requirements.
LTE (Long Term Evolution), also known as 4G is the perfect technology for building the next-generation of broadband public safety networks, delivering applications such as video-based situational awareness that more difficult with TETRA. LTE offers high throughput (up to 170 Mbps) and low latency (10 ms), making it compatible with any mission-critical application.
However, replacing TETRA with LTE is not a short term option, for many reasons. First of all, LTE does not yet support the voice communication features of TETRA and second, we cannot rip out and replace the huge TETRA installed base in one day.
Alcatel-Lucent demonstrated at TETRA World Congress a very interesting compromise: TETRA communications over an LTE network. A PMR user with a TETRA client application running on an LTE rugged terminal, can communicate with other TETRA users over an LTE network, while using all of the TETRA services. This option opens the way to TETRA/LTE hybrid solutions combining the best of the two technologies to provide broadband overlay services to existing TETRA networks.
Cassidian and Alcatel-Lucent recently announced a joint development agreement under which the two companies will provide an innovative mobile broadband solution for emergency response and security communications systems operating in the 400 MHz spectrum band.
Using LTE technology, the joint Alcatel-Lucent and Cassidian offering will support broadband data services such as mobile video security, location-based video services and smart vehicle integration of devices and applications to complement the current voice and data systems.
This will ease the adoption of LTE (no need for public safety agencies to buy expensive LTE frequencies from government) for using a hybrid LTE/TETRA solution (or LTE as an overlay of an existing TETRA network) and this also opens a better path for a later smooth migration from TETRA to LTE.
With the hybrid TETRA/LTE solution, this enables new applications and services that will change the way emergency responses are delivered.