The power of TETRA technology

11 March 2022

Hannu Aronsson, TCCA’s TETRA Applications Group

Hannu Aronsson, TCCA’s TETRA Applications Group

TETRA is recognised as a leading mobile communications technology that is delivering mission-critical voice and data services to public safety organisations and mobile workers worldwide. It is the technology upon which the UK’s Airwave network is built. TETRA solutions deliver exceptional secure and reliable critical voice services but the inherently rich data capabilities of TETRA are often under exploited. The data applications described in this article are real life examples of how end users can and are reaping added organisational value from their TETRA asset investments.

TETRA supports a variety of messaging applications: plain text messaging (Short Data Service - SDS): flash text messages that appear on screen immediately; messages that can be sent to a talkgroup or individual radios, with images attached. These applications support acknowledgement features to confirm to the control room that a message has been received by the radio, and that it has been displayed to the radio user. Predefined message templates and support for forms enable quick and easy updates and reporting on the move.

Many TETRA users provide their control rooms with real-time status updates – enabled by simple one-button updates from a radio and rapid processing in the control rooms. Status and SDS text messages are standardised to ensure interoperability between all TETRA radios and TETRA networks.

TETRA radios support “callout” which provides alarms and task management information from the control room and acknowledgements from users, similar to 2-way paging. For example, Norwegian firefighters use TETRA callout to efficiently dispatch operations. Callout is a standardised feature that works across all TETRA radios in the same way. With callout, control rooms can ensure information is read and acted on quickly. There are also dedicated pager TETRA devices available.

For public safety organisations, tracking the location of first responders is a critical safety and operational efficiency requirement. TETRA radios support Global Navigation Satellite Systems (GNSS) to enable location tracking with time and distance triggers to optimise network traffic. The TETRA standard Location Information Protocol (LIP) may be used to ensure efficient location tracking on large TETRA networks with radios from multiple vendors. Location can also be sent automatically when an emergency call starts, including Bluetooth-enabled indoor location tracking and Z-axis location - i.e. height and floor information.

TETRA radio functionality can be securely controlled remotely via data messages sent from the control room. SDS or status messages can trigger actions on the radio - e.g. changing the talkgroup or making sure the audio volume is on high. Only authorised systems can activate remote control actions. TETRA networks and radios also support over-the-air stun and kill to remotely disable lost or stolen radios.

TETRA SDS messages enable essential database lookups from mobile radio users, such as a vehicle licence plate check. The Finnish police and border guards, for example, have access to their databases from TETRA radios to check vehicles and persons in the field. Information is securely always available through the nationwide TETRA network.

Supervisory Control and Data Acquisition (SCADA) solutions are used within the industrial sector to collect, monitor and automate processes. TETRA offers multiple communication methods ideal for SCADA, from status and SDS messages, to packet data for IP-based protocols. For example, power companies can manage transformer substations, oil and gas companies can detect leaks and control pipeline flow rate and mining operations can monitor heavy machinery. Many power utilities use TETRA devices to control power stations, photovoltaics, and wind generators and for distributing alarms in real time via SDS, Voice Alarm or callout.

The same TETRA radio solutions that are providing reliable voice communications for buses, subways, trams, railways and airports can also provide data applications to increase operational efficiency - e.g. location tracking, keeping passenger information displays up to date and accessing operational information from TETRA radios. New Jersey Transit and major airports in the US are using TETRA for voice, location, and other applications to optimise their operations.

Public announcements (PA) and audio alarms are key to safe operation and communication to workers inside and outside oil and gas plants. TETRA SDS messages from the control room can trigger RTUs (Remote Terminal Units) to activate sirens and play audio PA messages, to quickly alert everyone in case of a gas leak, fire alarm or other incident. In addition to data-enabled alarms, the control room operator can use a group call to specific PA systems to share any important information by voice.

In addition to audio voice accessories, there are data-enabled accessories for TETRA radios, including Near Field Communications (NFC) readers, indoor location beacon readers, gas sensors, temperature sensors and barcode readers. These accessories can send collected information and alerts over the TETRA network to the control room, using the standard TETRA messaging features. TETRA radios can also connect to on-person sensors via Bluetooth and monitor, for example, gas in the environment, heart rate or body temperature and alert the control room over TETRA if the situation becomes dangerous.

Many users carry a TETRA radio and a smartphone. To simplify operation, an application installed on the smartphone can be used to control the TETRA radio - e.g. change talk groups or perform messaging - via a Bluetooth link. For some users, like covert operatives, this also enables them to communicate over TETRA while appearing to play with their smartphone.