Working as part of a multi-year partnership, Boldyn Networks and Transport for London (TfL) are ramping up their connectivity mission to introduce high-speed mobile coverage – with the first sections of the Circle and District line now live.

Key stations that are a hub of connectivity are already connected, with more expected to go live in the coming months, which includes sections of tunnel that are kitted out with fibre.

According to both parties, the project remains on target to have mobile coverage across the entire network by 2026.

Behind the scenes of the TfL partnership

Boldyn Networks is working to introduce more sections as quickly as possible, now that much of the groundwork has been completed. Installation work will also continue along sections outside of Central London and where smaller tunnelled sections need to be treated individually.

“Our long-term partnership with TfL to extend reliable 4G and 5G mobile coverage across the London Underground is grounded in improving everyday journeys for millions of people,” said Nick Hudson, chief operating officer for the UK & Ireland at Boldyn Networks. “A project of this scale demands extraordinary engineering effort and close-knit collaboration with TfL, with work often carried out overnight in one of the world’s most complex transport networks.”

Capacity interviewed Nick Hudson in December about the TfL project, which you can read HERE.

He added: “We’re immensely proud of what’s been achieved so far, and each section completed brings us closer to our goal of creating a more connected London for those who visit the city and those who call it home.”

Boldyn Networks is a global builder, designer and operator of shared infrastructure and, in addition to the TfL project, has undertaken similar jobs on the New York Subway, the BART system in San Francisco and also deploying Distributed Antenna System (DAS) in Rome.

“[London] will be the biggest DAS system globally once globally once it’s finished at the end of this year,” Hudson said on location during a tour of some of the infrastructure, which Capacity attended. “We’ve signed a 20-year concession with TfL, and we have roughly 17 years left.”

Boldyn Networks are investing £1 billion in 4G and 5G infrastructure across 350 locations across tunnels and stations. Given the uniqueness of the London Underground environment, approximately 400 engineers work on the project regularly overnight to deliver the project during limited overnight hours on the busy transport network.

With tunnel infrastructure completed last year, both companies have now turned their attention to fitting high-power radios in the stations. Committed to installing a fibre backbone in London, Boldyn seeks to improve connectivity above and below ground and bring multiple benefits to local businesses and communities.

“The equipment for the mobile network operators is connected to what we call base station hotels – like a data centre – five or six kilometres away,” said Matthew Griffin, head of commercial telecoms at TfL, during the tour. “The base station hotel interconnects to the mobile network operator equipment and then off to the rest of the network.

“It’s a standard distributed antenna system cabling in a station, harnessing fibre optic cables.”

The design of the servers at each station was critical, Griffin added, saying: “We invested in surveying infrastructure and identifying obscure rooms throughout the network.”

Advancing mobile networks

The work also supports the Mayor of London’s pledge to improve digital connectivity in London to increase innovation, productivity and growth.

All four mobile network operators (Three UK, EE, Virgin Media O2 and Vodafone) are participating in the rollout – with the expanding coverage also hosting the new Emergency Services Network (ESN). The ESN, when fully operational, will be able to give first responders immediate access to life-saving data, images and information in live situations and emergencies on the frontline.

“One of the things we have to do is make sure that if you call 999, the emergency services go to the correct place,” Griffin explained during the tour. “When you call 999 in the tunnel, we want the emergency services to go to a station – not halfway along the tunnel.”

He added: “We have made location data from the mobile network designate you at one of those stations so emergency services will go to the right place. It means your location will always show as a station rather than halfway along the tunnel.”

Both Boldyn Networks and TfL are working to introduce high-speed 4G and 5G mobile coverage across the entire Tube, Docklands Light Railway (DLR), Elizabeth line network and parts of the Overground network in the city.

The mammoth project speaks to the growing importance of ‘always-on’ connectivity, strengthening digital access for people and business.

Isabel Coman, director of engineering and asset strategy at TfL added: “The latest stations and tunnels to go live now mean that we are on a clear path towards having 4G and 5G mobile coverage across the whole network by the end of 2026.

“We hope that customers enjoy benefitting from being able to stay in contact with friends and family, shop online and stay on top of the latest news and sports results while travelling across London.”

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