Taking off with TETRA

TETRA (Terrestrial Trunked Radio) is the global open standard for professional mobile radio communi – cations systems. TETRA is used through out the world to deliver secure, reliable and robust critical communications for professional users. It is the technology of choice for public safety agencies, and is deployed by governments around the globe looking to protect their citizens.

The adoption of TETRA technology by the public safety sector catalysed its use in a wide range of markets, and today the second largest sector using TETRA after public safety is transport. The use of TETRA in transport is increasing yearon- year, and a significant proportion of that growth is due to the implementation of TETRA in airports – in fact the first commercial contract for TETRA implementation anywhere in the world was for Gardermoen Airport in Oslo in 1996. The dynamics of today’s airport environments, with their rapidly changing requirements, demand innovative and comprehensive solutions within the field of mobile communication.

Airports around the world use TETRA to ensure reliable and secure communications. One of the latest implementations of a TETRA system is at Billund Airport, which covers 400 acres in the south-west of Denmark and handles more than 2.6 million passengers a year for both domestic and international travelling. Bangalore was India’s first international airport to adopt TETRA. In any world-class airport, a robust comm – unications network on a digital platform is critical to supporting the many facets of airport ground operations.

TETRA enables the integration of digital voice capabilities and data communications on a single platform, and ensures high voice quality for clear communication throughout the airport operating units. TETRA systems are scalable; able to grow with the requirements of an expanding airport.

The radios provide communication for many facets of the airport, such as baggage handling, fuel supply, maintenance, catering, immigration, customs and security and can be integrated with other IT and communication systems within the airport.

London’s Heathrow Airport has a TETRA system that covers all the airport terminals, Heathrow Express and a number of road tunnels. The system was initially installed in 2005 for Terminals 1, 2, 3 and 4 but has since been expanded to include Terminal 5 and the T5 Hex extension.

In a noisy airport environment, it can be difficult to communicate. TETRA delivers exceptional call clarity due to its digital technology and special coding algorithms that help to screen out background noise. Group calls can be activated at the touch of a button – inside 500 milliseconds – enabling almost instantaneous group communication, collaboration and coordination. Intrinsically safe radios are also available for use in hazardous environments. Many TETRA solutions also enable calls to be recorded for analysis to refine crisis management and operational procedures.

Communications security is obviously a prerequisite for airport organisations. TETRA builds on the inherent security strengths of digital technology, and protects the radio connection between devices and radio sites through the application of advanced Air Interface Encryption techniques. TETRA’s security measures deliver the strongest levels of protection; ensuring the privacy of conversations and the secure transmission of sensitive data.

A potential security loophole in networks – devices – is also addressed. Authentication at the connection between device and network controls traffic to ensure that transmissions are from approved users. If a terminal is misplaced or stolen it can be immediately disabled, preventing unauthorised personnel listening to private conversations or viewing sensitive information.

TETRA also enables networks to be partitioned. This ensures that different user groups and organisations have access to private communications over their own Virtual Private Network (VPN) securely tunnelled across the system. If interoperability between different organisations and user groups is required, this can be immediately and securely provisioned.

As well as airports, TETRA communications are used in rail and water transport, utilities, the oil and gas exploration, extraction and delivery industries, commercial, and retail and leisure organisations from car manufacturing plants to casinos. TETRA systems are regularly deployed to ensure resilient and secure communications at major sporting events such as the Olympic Games, the FIFA World Cup, and Formula One racing.

Hanover Airport

In airport environments, the emphasis is on efficiency. Personnel and their responsibilities need to be coordinated in a way that is no longer limited to set tasks and behaviours. An airport is a relatively small area to cover, and in most cases this area is strictly controlled.

Within this restricted area there is a high communications traffic load, and the traffic is generated by many different groups. A complex system environment is necessary to operate an airport. Many systems and people have to work together successfully to enable an airport to work efficiently.

Hanover Airport has two runways, three terminals, cargo and maintenance areas, car parking, hotel and logistic areas, and is the ninth largest airport in Germany, with an area size of approximately 10km2. The airport handles approximately 76,000 flight operations per year; around 210 flight operations per day. Some 5,500 employees take care of the airport.

The TETRA communications system is fully integrated into the existing environment and workflow of the airport, managing high traffic load from a variety of user groups. These include air traffic control, fire brigade, ground service, check-in and cargo service. A mobile radio communication system on an airport cannot simply be a voice system. It is a complete end-to-end solution.

All these different user groups are using one physical TETRA system. The advantages of sharing the same physical network among different organisations are: reduced costs for infrastructure; reduced costs for running the network; interoperability among the different user groups; and efficient use of radio spectrum.

By using TETRA, Hanover Airport can provide a virtual private network environment for each user group. Each virtual network guarantees the complete communication independence of each organisation. The TETRA system has to provide open interfaces to connect operation dependent control centres and applications. Because TETRA is specified as an open standard, each organisation can choose the most appropriate terminals – for instance radios operable with gloves, or without keyboard and display for undercover purposes.

In terms of user distribution and traffic loading, at Hanover Airport 95 per cent of the radio users are located in just 20 per cent of the airport area, concentrated around the terminals, cargo area, baggage area and apron area. TETRA infrastructure can support this high traffic load frequency efficiently due to its standardised trunking mechanism.

The capabilities of TETRA mean that Hanover Airport can interconnect all the responsible organisations. These relationships include:

● Interface to the in-building announcement system so a TETRA user can make announcements to people inside the terminals, for instance

● Interface to the integrated ground cockpit communication, so a TETRA user can talk to the cockpit of an approaching aircraft

● Communication from and to the air traffic control staff

● Communication from and to the apron control centre

● A line connected interface from the TETRA system to the control centre of the fire brigade. Calls from and to the fire fighters can be made directly from the control centre workstation

● Support of a security guard control application. The application uses the TETRA system to transfer information to check whether the security guard is at the right time at the right place

● An interface to the universal flight information system. A TETRA user can get flight information, such as arrival/departure time and gate information, directly on the display of the radio

● Interface to a billing system. This is necessary because the TETRA system in Hanover is operated by an IT and telecommunication service provider

● The TETRA system has to provide a lawful interception interface

● A Gateway to exchange short data messages from a mobile TETRA radio user to a GSM/3G user

● An interface to the airport telephone system to allow direct calls from TETRA user to a telephone subscriber and vice versa

● The interface to the airport IP network allows direct IP data transfer from a TETRA user to applications connected to the fixed IP network – i.e. database enquires

● Communication between mobile analogue users and digital TETRA users during system transition, until such time as all mobile radio users are equipped with digital TETRA radios

● An interface to the aircraft radio, so a TETRA user can listen on the different aircraft radio channels – for example, to get weather forecast information or to listen to the tower/pilot communication

● An interface to an object call server, to call TETRA users by group

● A direct interface to the network service and maintenance centre to enable any issues to be immediately addressed.

‘Turning around’ an aircraft ready for the next flight is time critical workflow in an airport. Only if the aircraft is in the air (and of course passengers are on board), does the airline earn money. Many different organisations are necessary (e.g. cleaning, catering, fuelling, security) to ensure effective turnarounds, and all have to at the right time at the right place. And they have to talk to each other.

TETRA and suitable applications (a flight dispatch management system, for example) support this time critical workflow by optimal management of the field staff via Dynamic Groups Number Assignment (DGNA). Within the TETRA system, DGNA groups can be created or deleted on demand by a user activities or an application. These group addresses can be set or removed in mobile radio stations via the TETRA air interface. It is possible to assign a mnemonic name to the dynamic group address, and subscribers will be dynamically attached to or detached from the dynamic group. This enables a group to be created by flight number, ensuring that all appropriate resources for handling an incoming or departing flight can communicate with each other.

The same person with the same TETRA terminal can be assigned to different groups, depending on the current flight to dispatch. With the push of a single button, communication to all within the group is enabled.

(Information courtesy of Rohde & Schwarz)

Lyon-Saint Exupéry Airport

Located 25km east of Lyon, and covering an area of 2,000 hectares, the Lyon-Saint Exupéry Airport handles around eight million passengers a year. TETRA radios are deployed by a variety of teams across the airport site to keep operations running smoothly, including baggage handling, engineering and fire and rescue, as well as security personnel.

Lyon-Saint Exupéry Airport selected TETRA for its radio and communication needs, replacing four legacy analogue networks. Alongside seamless voice and data communications for operational, public safety and security staff, the new shared TETRA network delivers impressive lone-worker protection thanks to the ability to locate every single terminal operating on the network in real-time.

Worker safety is a primary consideration for the airport, which needs to meet stringent safety standards in a variety of operational environments, including its secured parking areas. The TETRA system enables the network tracking solutions, outdoor and in-indoor radio localisation, real-time management and mandown capabilities needed to ensure workers are protected at all times regardless of their location.

Many of Lyon-Saint Exupéry Airport personnel work in hazardous or mission-critical environments and the airport control dispatching centre needs to track their every movement so they can send coordinated assistance to them instantly, if required.

This ability to locate every single TETRA radio in use enables the airport to improve the management and safety of its resources, giving controllers the ability to locate the position of airport vehicles – where mobile radios are installed – as well as individual personnel carrying the handportables. To ensure pinpoint in-building accuracy at all times, over 150 radio beacons are installed across the airport’s indoor areas.

(Information courtesy of Sepura)

About the author

Phil Kidner is CEO of the TETRA + Critical Communications Association (TCCA), which represents a member – ship of over 160 organisations around the world. The TCCA is dedicated to supporting the mobile communications needs of pro – fessional users worldwide. In his role as CEO, Phil’s main responsibility is to promote the TETRA standard and its benefits of security, resilience and interoperability, and manage its evolution to ensure the needs of all users are met. TETRA is now present in more than 124 countries and all continents.