In 2005, the TETRA MoU Association celebrated its tenth anniversary, a landmark that underlined the foothold that TETRA, as a digital radio solution, has taken in the world of mobile radio.
TETRA was originally conceived in the 1990s, primarily as a public safety technology, and the first implementations were, indeed, for public safety networks, for example the States of Jersey TETRA network. However, by early 2000, with the rise of the telecoms boom, TETRA was also being seen by some commercial operators as a potential competitor to public cellular networks. In Europe, Dolphin had ambitious plans for a pan-European commercial TETRA network that would support very large numbers of users. During this period much of the TETRA standardisation effort was directed towards providing features for commercial networks, including high-speed data (based on GSM EDGE technology) and GSM-like steering of traffic. However, within a few years this dream was shattered, and it now seems inconceivable that TETRA will ever be used to implement large commercial networks. In the meantime, standardisation effort has refocused once again on public safety and related sectors, such as transportation, to provide a secure, integrated high-speed data solution.
The advent of TETRA has also seen a different approach to radio solution procurement, especially in the public safety and transportation markets – the rise of the managed service contract and the different commercial vehicles that can be used to deliver radio solutions.
The move to solutions that deliver multi-agency, country-wide, radio communications through third-party agencies created to deliver these solutions has required a shift in emphasis in the skill sets required by ICT consultancies to support clients embarking on such programmes. Specifications now tend to be output-based, determining the functionality to be delivered, rather than detailed technology specifications and the service levels to be associated with the functionality.
This approach has also had the effect of shifting the axis of project risk, especially in relation to technical and commercial risks; on the other hand, risk associated with how the system is to operate has remained firmly with the end-users, and as TETRA has developed through its various stages of maturity as a telecoms standard, there have been a number of technical risks that have required careful mitigation.
The first tranche of major TETRA public safety contracts were let in Belgium, the Netherlands and the UK. Tracking these contracts, which have been delivered through three different commercial models, by three separate organisations, we find a number of similarities. In the early days, the ability to deploy integrated, national networks proved a challenge, thankfully a situation equipment suppliers have now resolved. Finding and developing sufficient radio sites to provide the level of coverage that public safety users demand was also an issue and, indeed, continues to be difficult.
Another issue common to each was the ability to ensure availability of co-ordinated frequency spectrum. This remains a challenge, as is managing expectations of users given the level of the original marketing hype surrounding TETRA that so many business cases were founded upon. These days, each of these projects can be considered a success in their own right, and each delivers a range of different services and applications to meet the demands of public safety users in this ever-changing climate of security and mission critical communication.
Using TETRA as a means for nationwide mobile communications requires consideration of a solution that is so much more than just implementing a few base stations and switches, then connecting them together. The diverse requirements of the different blue light services adds its own complication in terms of delivery to communication control rooms. At the heart of all of these TETRA implementations are complex, IP-driven networks that have evolved from the first generation, circuit switched, TETRA networks that were introduced back in the late nineties. Now most manufacturers of large-scale mobile radio systems are consolidating on a generic delivery platform, including the core network and the associated network management systems, which can support a number of different air interface technologies, for example TETRA, ACPO25 or Tetrapol.
TETRA as a technology has matured, and is now able to deliver the original expectations of secure voice and data communication. It provides a platform to enable multiagency operation, and it continues at the forefront of professional mobile radio solutions. TETRA will not necessarily be the technology of choice in meeting all user requirements. In fact, the challenge over the coming three to five years will be for TETRA to continue its development programme. It’s important that current investment benefits from advances in technology. This includes managing the technology refresh expectations of the managed service providers charged with delivering TETRA based solutions.