Hytera Mobilfunk: “TETRA will remain the decisive technology for many years to come”

Interview: Bernhard Klinger, Chief Business Development Officer and TETRA expert at Hytera Mobilfunk GmbH.

In your opinion, what is the importance of the TETRA standard for professional mobile radio today and what role will TETRA play for mission- and business-critical communication in the future?

Especially in times of crisis, mission- and business-critical mobile communication is indispensable for maintaining the security and supply of the population.

Despite all the developments in broadband and the current 5G discussion: for mission- and business-critical voice communication, the current TETRA standard will continue to play a decisive role until beyond 2030 and will be one of the most important technologies used. For this reason, the "3rd Generation Partnership Project" (3GPP), a worldwide cooperation of bodies for standardisation in mobile radio networks, is standardising the interplay between narrowband systems such as TETRA and LTE/5G technology, thereby laying the foundation for long-term parallel use of both technologies.

At the same time, the European Telecommunications Standards Institute (ETSI for short), has started work on next-generation TETRA security features. The ETSI is working on the complete protection of the TETRA system against the increasing threats of cybercrime. Among other things, additional encryption algorithms will be integrated into the standard to withstand cryptanalysis into the 2030s and beyond.

Why will TETRA remain the leading technology for mission- and business-critical mobile voice communication for a long time to come?

There is now an undisputed need for mission-critical broadband services for professional users in public authorities, organisations and companies. LTE/5G services and systems enable innovative video and data applications. However, they will complement rather than replace TETRA or narrowband systems. And this will be the case for at least the next decade, probably beyond.
Despite all the technical progress with regard to broadband, secure and highly available voice communication with its special services will remain indispensable for the professional mobile radio user for an as yet unforeseeable time. Because it is precisely here that the major differences between TETRA and LTE/5G lie:

TETRA was specifically designed for mission-critical voice and low throughput data services, such as group calls, priority and emergency calls, direct mode and late entry. TETRA stands for guaranteed, extremely fast and deterministic call setup under 500 milliseconds and offers specially adapted terminals for a variety of different applications.

LTE, on the other hand, has its origins in the commercial sector and was specifically designed to transmit large amounts of data efficiently. Although 3GPP is endeavouring to standardise mission-critical voice and data services for LTE (what are known as MCx services), it is still a long and rocky road from standard to mission-capable and guaranteed reliable and secure products and solutions.

In which area does TETRA still hold a clear advantage over broadband technologies?

Within LTE technology, for example, there are problems with Direct Mode (DMO), i.e. direct communication between terminals without a fixed infrastructure, unlike TETRA. DMO is however essential for mission-critical applications. The issue has been addressed by 3GPP with the Proximitiy Service in the LTE standard. However, there remain significant differences in the transmitting power of broadband terminals and the associated range. The range of wideband terminals is significantly lower than that of TETRA terminals, for example. This means that the DMO in wideband terminals is not yet really suitable for mission-critical applications.

In addition, there are problems with the availability of chip sets for broadband terminals that support direct mode, since developing these chip sets is only worthwhile for the industry if a certain number of units are produced. And the demand obviously does not seem to be sufficient at this moment. But there are still many more problems to be solved within broadband technology to adequately replace the performance features of TETRA.

All in all, since its introduction over 20 years ago, TETRA has been continuously developed to meet the needs and requirements of its users. LTE/5G and subsequent standards will also have to follow this path. And that simply takes time.

How do you think the PMR market will develop over the next 10 years? What fundamental changes do you expect?

There is no doubt that broadband applications are increasingly finding their way into the professional environment - initially as mission-supporting applications, but in time no doubt also for mission-critical applications. In addition to the communication systems themselves, mission-critical high-bit-rate end-to-end applications will increasingly complement the environment of professional mobile radio. With these broadband applications, new players will also emerge in professional mobile radio - especially with regard to the high software content, cloud solutions, big data, artificial intelligence and video.
In addition, commercial broadband networks will continue to be put to the test as to whether and under which legal and regulatory framework conditions these networks can or may be used for mission-critical applications.

On the other hand, the requirements for mission-critical or business-critical communication networks will remain unchanged in the future and apply equally to voice and data applications in the narrowband as well as in the broadband area.

What requirements for mission-critical communication networks will broadband solutions also need to be able to meet in the future?

Very important and therefore the first thing to mention is the guaranteed availability of the network. This also includes sufficient available transmission capacity, especially in the event of operations, for example in the case of major emergencies. But blockages by third parties must also be excluded. This can be the case in commercial networks, for example. Radio coverage must also be available wherever it is needed - for example, in rural areas.

In addition, the failure safety of the components must be guaranteed, for example through redundant technology and self-sufficient power supply. Guaranteed availability also includes secure sites, for example protected against sabotage, vandalism and natural disasters.

Another requirement is the security of the network, especially with regard to securing access against attacks from the outside, keyword cyber security. This means security against voice and data interception, but also security against data manipulation.

And finally, mission-critical communication services such as group calls, emergency calls and direct mode and fast, guaranteed call setup are also indispensable. Especially in mission-critical applications, interfaces or connectivity to control centres, databases and applications will continue to be essential in the future and will become even more important.