Heathrow Express has claimed a world first for its
deployment of
wireless broadband on trains that travel
underground through 6km of tunnels.
The main challenge for the engineers was to develop and test
technology that could be used on moving trains, since most Wi-Fi
implementations use fixed points, which can guarantee that
connections remain stable.
The mobile network was designed and implemented for Heathrow
Express by Nomad Digital and T-Mobile. It allows travellers to use
T-Mobile's premium Wi-Fi service to check e-mails and surf the web
from their laptops on the 15-minute journey between Paddington
Station and Heathrow Airport.
The project, which ran from December 2006 to the end of March,
involved refitting 14 trains with antennae and other equipment, and
fitting tracks with wireless base stations, said Jay Saw,
commercial director at Nomad Digital.
The network uses 802.16 Wimax wireless broadband technology
running at 8mbps and T-Mobile's cellular HSDPA technology, which
operates at 3.4mbps.
The trains have black box devices that switch seamlessly between
the cells by listening out to at least two base stations at any one
point, said Saw. This approach meant that a strong network
connection could be maintained, he added.
The network design had to meet the approval of several rail
bodies, and the deployment had to be scheduled months in advance
because trains needed to be held at depots.
Heathrow Express is now exploring the use of wireless CCTV on
its trains. "It has huge implications for security," said Saw.
Ofcom report says UK needs high-speed fibre in
the last mile >>
Wireless VoIP market to grow rapidly
>>
Welcome to the wireless city >>
City switches on Wi-Fi network >>
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