Mobile services go live in the Channel Tunnel ahead of Olympics

People travelling through the Channel Tunnel can now access mobile services 100 metres under the sea, at least for the French end of the journey.

Groupe Eurotunnel said on Wednesday that it and the French operators Bouygues Telecom, Orange and SFR had set live a 2G and 3G system for sub-sea travellers. That only applies to the south side of the tunnel — the British north side will also get connectivity, but only after the Olympics.

"Eurotunnel is proud to be able regularly to improve the services we offer to our customers through major technological innovation, this time based on the expertise of Alcatel-Lucent," Groupe Eurotunnel chief Jacques Gounon said.

The biggest achievement in installing the system along the 53km tunnel was the fact that it all got done in 10 months, while operating a full train service.

Transmission is achieved through the use of 'leaky feeder' technology, which basically involves a long cable that serves as an antenna, emitting (or 'leaking') and receiving radio signals. This is accompanied by a repeater every 750 metres.

There is more to the deployment than that, though — one obstacle was getting the GSM-P (primary GSM) and GSM-R (railway GSM) systems to work together inside the Tunnel.

"As a result of this collaboration with Eurotunnel, and which has used many of the different technical skills we have at Alcatel-Lucent, we are very proud to have contributed to the provision of new communication services on board the trains in the Channel Tunnel," Alcatel-Lucent France chief Pascal Homsy said.