British Rail Telecommunications - British Rail Telecoms Assets

British Rail Telecoms Assets

This section briefly describes the assets that comprise British Rail’s telecom systems and networks.

The fixed bearer network is at the core of railway communications and thus is vital to the operation of the railway. It provides essential circuits for signalling and electrification control systems, train radio systems, lineside communications, level crossing CCTV, customer information systems as well as more general IT and business telephony needs.

The fixed bearer network infrastructure comprises transmission systems and telephone exchanges linked by a fibre optic and copper cable network that is located mainly within trackside troughing routes.

British Rail had several analogue radio networks that support mobile communication applications for drivers and lineside workers. These radio networks comprise of base stations, antenna systems and control equipment. The National Radio Network (NRN) was developed specifically for the operational railway; it provides radio coverage for 98% of the rail network through 500 base stations and 21 radio exchanges.

The NRN offers full access to the BRT telephone network; public service telephone network (PSTN) dialling, including international, is also available. It can provide 'dedicated' open channels on talk-through mode for incident management and an override priority facility to ensure that all emergency calls are immediately connected to the railway's Train Control Offices (TCO) and Electrical Control Rooms (ECR). The NRN and ORN are based on analogue radio technology and provide a high level of coverage throughout the railway network for mobile communication at the trackside. The ORN offers facilities for driver emergency communication with the local train control office. The RETB system is based on similar technology as the NRN and ORN but provides data communication for signalling token block exchange as well as voice communication.

Secure communication between drivers and signallers is provided by the Cab Secure Radio (CSR) systems located in various parts of the country. This application of analogue radio technology is designed to offer complete radio coverage at the trackside within the limits of its deployment. Fixed communication at the trackside is provided by lineside communication systems. These systems are primarily provided for signallers’ communication with drivers and the public through telephones located on signal posts and at level crossings.

Signal Post Telephones (SPTs) and other lineside phones are linked to telephone concentrators at the signal box.

Special self-monitoring systems (PETS) are also provided for high-risk level crossings.

CCTV systems are provided on platforms where driver only operation train services are operated and at some stations with sub-surface platforms. These self-contained systems comprise of cameras, monitors, cabling and control equipment.

Voice recorders are also classed as telecoms assets.