IEC TR 61375-2-7:2014

Overview

IEC TR 61375-2-7:2014 - "Electronic railway equipment - Train Communication Network (TCN) - Part 2-7: Wireless Train Backbone (WLTB)" is a Technical Report from the IEC that documents a radio-based Wireless Train Backbone (WLTB) for distributed power freight trains. It describes the protocol stack (physical, data link, application layers) and the distributed power application, plus commissioning (“inauguration”) procedures and datasets. This TR is part of the broader IEC 61375 TCN family and provides a state-of-the-art reference rather than a prescriptive international standard.

Key topics and technical coverage

The report provides structured, practical information on the WLTB, including:

• Architecture and framework for train communication backbones and distributed-power train compositions (figures illustrate node roles and communication flows).
• Physical layer considerations: transmission power, channel/frequency planning, modulation options, antenna and feeder specifications (tables list channel/frequency and antenna parameters).
• Data link layer functionality**: protocol structure and procedures required for reliable radio link operation.
• Application layer and PDUs: communication schedules, addressing schemes, PDU structure and message flows (command/data/status), and network security considerations.
• WLTB inauguration (commissioning): parameters, step-by-step procedures, and detailed user datasets for inauguration messages (InaugInfoCheck, InaugTest, InaugCompletion).
• Process data communication: definitions for Local Traction Vehicle (LTV) and Global Traction Vehicle (GTV) datasets and their use in control and monitoring.
• Distributed power operation application: operating conditions, functional models (remote control), function definitions (train composition, traction, braking, pneumatics, emergency procedures), handling of communication loss and data verification.
• Annexes and supporting tables (nation code, dataset tables, flow charts, and logic diagrams).

Practical applications and who uses it

IEC TR 61375-2-7 is directly applicable to:

• Rolling-stock manufacturers and system integrators implementing radio-based train backbones for distributed locomotives.
• Communication equipment vendors designing WLTB transceivers, antennas and protocol stacks.
• Railway signaling and control engineers specifying remote control and distributed power operation.
• Commissioning teams and maintenance staff using the inauguration procedures and user datasets.
• Railway operators and research organisations assessing interoperability and safety implications of wireless TCN architectures.

Related standards and context

• Part of the IEC 61375 TCN series (Train Communication Network). Users should consult other IEC 61375 parts for wired backbones, conformance and complementary specifications.
• As a Technical Report, IEC TR 61375-2-7 is intended as a technical reference to support design, implementation and testing of WLTB solutions rather than as mandatory normative requirements.

Keywords: IEC TR 61375-2-7, Wireless Train Backbone, WLTB, Train Communication Network, TCN, distributed power, railway communication protocols, physical layer, data link layer, inauguration, PDU, remote control.