London's underground network is set to receive mobile coverage by 2012 according to the Sunday Telegraph. The cost of deploying such a network is estimated to be in the region of hundreds of millions and the bill is to be footed by the 5 main mobile networks in the UK, O2, Orange, T-Mobile, Three and Vodafone.
It is understood that London's Mayor, Boris Johnson, helped broker the deal together as previous efforts to make London Underground better connected have never come to light. A tender to run a trial of mobile coverage on the Waterloo & City line to begin in 2008 never produced any viable solutions. The newly planned system is thought to use a 'leaky feeder' antenna system whilst in tunnels which is made up of a cable running the full length of the tunnels with holes in its outer sheathing to allow the signal in and out which will be picked up by transmitters on each carriage.
Earlier in the year, Boris announced that London was to get total Wi-Fi coverage which is also to reach on to underground stations allowing the ever more connected smartphone user to keep in touch.