Technical Committee (TC) Terrestrial Trunked Radio and Critical Communications Evolution (TCCE) Activity Report 2019

Chair: Brian Murgatroyd, Umlaut Communications GmbH

Responsible for the design and standardization of TErrestrial Trunked RAdio (TETRA) and its evolution to critical communications mobile broadband solutions.

TETRA (Terrestrial Trunked Radio) is the leading technology choice for critical communications users. With a projected 5.3 million terminals in use by 2021 and an installed base growth rate of 6.1%, the use of TETRA in security as well as other business-critical markets such as the transportation, military, commercial and utilities sectors is forecast to grow strongly up to 2023.

TETRA is designed to address a specific set of communication requirements. These include high reliability, single and group calling capabilities, PTT (Push-To-Talk), and the possibility for direct peer-to-peer communications in situations such as natural disasters and emergencies when the supporting network is unavailable. Accordingly, much of the work of our TETRA and Critical Communications Evolution committee (TC TCCE) is driven by the requirements of Public Protection and Disaster Relief and other mission-critical services.

The committee’s primary responsibilities include:

  • Provision of user driven standards for authority-to-authority secure voice and data services and facilities over broadband and narrowband air interfaces
  • Collection and specification of requirements from relevant stakeholders such as Emergency Services, Government, Military, Transportation, Utility and Industrial organizations as well as Public Access Mobile Radio (PAMR) Operators
  •  Development and maintenance of the existing TETRA standard
  • Production of ETSI deliverables addressing both TETRA and mobile broadband critical communications
  • Co-ordination of activities with other European and International Standards making bodies to avoid duplication of deliverables

Designed as a narrowband system, TETRA today cannot support all of the growing demands of emergency services for additional Mission-Critical capabilities such as streaming high-quality video from the scene of an accident. Reflecting these evolving needs – and an opportunity to benefit from the economies of scale of the mobile broadband ecosystem – the community of TETRA users has asked the Third Generation Partnership Project (3GPP™) to determine how this functionality can be realized using LTETM or 5G systems running over public network operators’ licensed spectrum.

This evolution to the use of mission-critical broadband solutions will depend heavily on the development of interworking solutions including a TETRA to broadband interface.

In response to feedback from 3GPP, as a priority in 2019 we continued to develop specifications covering the detailed interfaces between Mission-Critical broadband systems and TETRA, as well as the required security between the two systems. To optimize this standardization activity, existing standards for technologies such as LTE (and later 5G) will be enhanced by interfaces and applications that make them suitable for Mission-Critical applications.

In support of this work, close cooperation continued with the 3GPP WG SA6 MCPTTC (Mission Critical Push to Talk) and with the TCCA (The Critical Communications Association). Within this framework, ETSI’s successful 4th Mission Critical Plugtests™ event achieved the goal of validating the interoperability of a variety of implementations using different scenarios based on 3GPP Mission Critical Services in Release 14.

In 2019 the committee published various specifications as deliverables to maintain and further develop the TETRA standard and the move to critical comms broadband.

These included revisions to parts of the TETRA specification supporting Voice plus Data (V+D), namely Part 2 [TS 100 392-2] and Part 7 Security [EN 300 392-7], while publishing a new subpart [TS 100 392-19-2] on interworking between TETRA and broadband systems, addressing speech transport format. We also updated our Technical Specification on Plugtests™ scenarios for Mission Critical Services [TS 103 564].

Work was also completed on a set of eight standards (EN 300 392-3-X) for Interworking at the Transport layer independent Inter-System Interface (ISI), EN 300 392-1 for the General network design, EN 300 392-5 for the Peripheral Equipment Interface (PEI) and EN 300 392-9 for the general requirements for supplementary services.

During the year work also progressed on the development of new encryption algorithms to complement the existing set relating to TETRA. This reflects the needs of users to keep TETRA up to date through to the 2030s. 

Look out for in 2020 – TC TCCE work in progress

  • Additional encryption algorithms for TETRA will be largely completed in 2020
  • Revision to Technical Specification (TS) on Voice plus Data (V+D); Part 2: Air Interface (AI), with improvements for group addressed packet data for pi/4 DQPSK and QAM applications will be completed by December
  • TS on Voice plus Data (V+D); Part 19: Interworking between TETRA and Broadband systems (Sub-part 1: Critical Communications Architecture for Interworking between TETRA and broadband applications) will be completed in 2020
  • A HEN specific to TETRA radio equipment covering essential requirements of article 3.2 of the Directive 2014/53/EU has been developed by TCCE and will be sent during February to ETSI TC ERM for completion and publication
  • EN 300 394-1 is the old TETRA conformance specification; it is being updated as TS 100 394-1 as a testing specification