Terrestrial Trunked Radio (TETRA) is a digital trunked mobile radio standard developed by the European Telecommunications Standards Institute (ETSI). The purpose of the TETRA standard was to meet the needs of traditional Professional Mobile Radio (PMR) user organisations such as those listed below. The air interfaces, network interfaces as well as the services and facilities are specified in sufficient detail to enable independent manufacturers develop infrastructure and radio terminal products that would fully inter-operate with each other. For example, radio terminals from different manufacturers can operate on infrastructures from other manufacturers. The ability for full interoperability between different manufacturer’s products is a distinct advantage of open standards developed by ETSI. As the TETRA standard is supported by several independent manufacturers this increases competition, provides second source security and allows a greater choice of terminal products for specific user applications.

PMR Organizations Include:

• Public Safety
• Transportation
• Utilities
• Government
• Military
• PAMR
• Commercial & Industry
• Oil & Gas

Because the TETRA standard has been specifically developed to meet the needs of a wide variety of traditional PMR user organisations it has a scaleable architecture allowing economic network deployments ranging from single site local area coverage to multiple site wide area national coverage.   Besides meeting the needs of traditional PMR user organisations, the TETRA standard has also been developed to meet the needs of Public Access Mobile Radio (PAMR) operators. The TETRA standard is in practice, a suite of standards covering different technology aspects, for example, air interfaces, network interfaces and its services and facilities. Because TETRA is an evolving standard it has been developed in Releases (phases) known as TETRA Release 1 and TETRA Release 2. Even though both TETRA Releases have been completed, work continues within ETSI Technical Committee (TC) TETRA to further enhance the standard thus satisfying new user requirements as well as gleaning the benefits of new technology innovations. Outside of Europe the ETSI TETRA Standard has been formerly adopted in China and South Korea.

Since the first generation of networks were deployed in 1997, hundreds of TETRA networks have been deployed across the world.  Even though a considerable number of these networks are deployed in Europe, a rapid uptake is occurring in the regions of Asia, Middle East and South America.  Although all PMR market segments are already being served by TETRA, the largest market is that of public safety, where the trend is for the deployment of nationwide networks shared by all public safety organisations for reasons of economics (sharing), autonomy of operation for routine communications and the ability to fully inter-operate with other services during emergency situations and disasters.

The transportation market is the next fastest growing market, especially for Mass Rapid Transport systems and major Airports.  Interestingly, TETRA is also used by the military for non-tactical operations, a market application not originally anticipated for TETRA. The success and market uptake of TETRA has attracted many independent manufacturers and suppliers of TETRA products and services, thereby providing users with healthy competition, second source security and wide choice of radio terminal equipment for specific applications. The success of TETRA has also created a strong base of application developers who are able to provide a wide variety of applications for use with TETRA.

The TETRA Association
Recognizing that important market requirements outside the responsibility of ETSI needed to be addressed to ensure the success of TETRA, a number of organisations formed the TETRA MoU (Memorandum of Understanding) Association in December 1994.  Since it has been established, the TETRA Association has grown significantly and now provides a forum which acts on behalf of its members, being user organisations, manufacturers, application providers, integrators, operators, test houses, regulators, consultants, etc. The main objectives of the TETRA Association are to promote the TETRA standard and to ensure multi-vendor equipment interoperability. (source www.tetra-association.com)

The new service can accommodate Radio Frequency (RF) power and voltage on a massive scale. It combines high voltage isolation with screening to 18 GHz, whereby most other facilities only allow for testing at 50 Hz or at low voltage.

Previously the preserve of government establishments, the Roke High Voltage Facility will offer an additional option to both public and private sector organisations that wish to test and commission high voltage and high power RF equipment such as accelerator components, ultra high power RF amplifiers, associated transmission lines plus electrostatic systems.

The high end facility will be targeted at R&D specialists designing systems that require multiple high power amplifiers that have tight synchronisation demands and signal distribution complexity. In a controlled and isolated environment, the energising and test of high voltage power supplies, high power drivers and transmission lines can be conducted in complete safety.

Roke will also use the new high voltage test facility itself, allowing it to develop and test a range of novel high power systems for the RF and electrostatic accelerator community, plus systems for the military, energy and medical markets.

Alastair Cook, Industrial and Medical Business Sector Manager at Roke, said:

“A major issue for organisations wanting to test high power and high voltage systems is the availability of facilities and management of the hazards. Reliance on government or academic services can mean that an organisation outside that sphere of influence doesn’t get priority when booking in lab time or full system tests can’t be done. This presents a serious dichotomy for organisations that want to accelerate time to market for their products, but also need to conduct complex and often hazardous tests first. Our new High Voltage Facility represents the largest single investment Roke has made in testing for a number of years and we hope that organisations across the world will recognise the benefit of this unique and easy to access resource.”

The high voltage facility has two screened chambers, one for the equipment under test and a second to hold test equipment and power supplies. Control is performed from a remotely operated and isolated console from which tests can be controlled and progress viewed via a high resolution camera link and optically isolated test gear. The primary test chamber is 4.8m x 4.5m x 4.5m in volume and has double door access that can allow heavy structures to be maneuvered into position.

To complement the facility there is a team of trained and competent personnel to help customers using the service, along with a robust set of procedures to enable a safe operating environment.

About Roke Manor Research Ltd
Roke Manor Research Limited is wholly owned by Siemens, and based in Romsey Hampshire. Founded in 1956 and wholly owned by Siemens since 1991, Roke is one of the UK’s leading suppliers of innovative solutions and contract research and development. Roke employees 450 staff and has over 430 patents to it’s name. Roke pioneers developments in electronic sensors, networks, and communications technology.

About Siemens in the UK
Siemens was established in the United Kingdom 166 years ago and now employs 18,402 people in the UK. Last year’s revenues were £3.7 billion. As a leading global engineering and technology services company, Siemens provides innovative solutions to help tackle the world’s major challenges, across the key sectors of energy, industry and health-care. Siemens has offices and factories throughout the UK, with its headquarters in Frimley, Surrey. The company’s global headquarters is in Munich, Germany. For more information, visit www.siemens.co.uk
(source www.roke.co.uk)