Improving Radio Communications Along the Channel Tunnel Rail Link

European Antennas has said that it has been responsible for designing and manufactured antennas for Thales for use on Section 2 of the Channel Tunnel Rail Link (CTRL) project between Fawkham Junction in Kent and the recently opened St Pancras International station in London.

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The famous clock in St Pancras Station features a discreet antenna

Section 2 of the CTRL includes the provision of 65km of new high speed track allowing speeds of up to 186mph (300km/hr), bridges and structures along the route, and the construction of the three developments at St Pancras, Stratford and Ebbsfleet stations.

Thales was targeted with several key tasks relating to communications within CTRL. These included the provision of improved GSM-R and Cab Secure Radio (CSR) coverage for the railway operators to maximise safety and to provide coverage for the London Fire Brigade in the evacuation shafts from CTRL tunnels and passenger exit shafts.

The prestigious but demanding CTRL civil engineering project presented unique challenges for wireless communications with 25% of the new route in tunnels with trains travelling through at speeds of up to 150mph.

An environmental feature of this application was the wind speed caused by trains within tunnels and resultant vibration that would have to be absorbed. Antennas would therefore need to be impervious to their surroundings, be tough, reliable, have low wind loading and meet the RF requirements to an uncompromising specification. Antennas for installation within St Pancras International would need to be discreet in appearance to merge within the magnificent new station.

European Antennas designed eight antennas to meet these requirements. All the newly designed antennas had specific power levels and cover the frequencies for GSM-R, Cab Secure Radio and the London Fire Brigade services.

One of the development projects undertaken was that of a slim panel antenna that was designed to support the emergency services system in London tunnels and the associated emergency evacuation routes. Mounted inside a firewall of an evacuation tunnel, this antenna features long length insulated cable so that the radio could be mounted at a safe distance to ensure its use in an emergency. The antenna still maintained 8.4dBi gain and full coverage down the shaft.

Posted to the site on 28th November 2007