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O2 joins Brighton Main Line connectivity project
O2 and telecommunications infrastructure operator Cellnex have signed an agreement to end Brighton Main Line ‘not-spots’ for 300,000 daily passengers.
At a glance
Who: O2; Cellnex; Network Rail.
What: Cellnex, the UK’s largest independent operator of telecommunications infrastructure, has announced that O2 has signed an agreement to join its Brighton Main Line (BML) connectivity project.
Why: To end the rail-line’s “not-spots” for connectivity.
Where: The Brighton Main Line is a 108km corridor linking London, Gatwick Airport and the South Coast with Thameslink, Southern, Gatwick Express, Great Western Railway and London Overground Services.
Cellnex, the UK’s largest independent operator of telecommunications infrastructure, has announced that O2 has signed an agreement to join its Brighton Main Line (BML) connectivity project to end the rail-line’s “not-spots”.
The collaboration will see O2 access Cellnex UK’s purpose-built neutral host infrastructure, enabling the phased rollout of high-speed mobile connectivity, including 5G, to customers across the entire route over the coming months.
This includes major commuter stations, London Victoria, London Bridge, and Clapham Junction. The agreement follows Cellnex signing telecoms group Three UK in 2023.
UK’s highest-density rail routes
The Brighton Main Line is one of the UK’s highest-density rail routes: a 108km corridor linking London, Gatwick Airport and the South Coast with Thameslink, Southern, Gatwick Express, Great Western Railway and London Overground Services. It serves more than 300,000 passengers every weekday, of which 50,000 are travellers to and from the second busiest airport in the UK, and accommodates 1,700 daily train movements.
State of the art indoor coverage solutions are being deployed to significantly enhance mobile phone connection in three of the most important London stations, London Victoria, London Bridge, and Clapham Junction, which account for roughly 19 per cent of railway passenger traffic to and from the capital from outside London.
“This collaboration stands as one of the most significant end-to-end telecommunications infrastructure deployments in British railway so far, and we are proud to be setting a new standard for the UK’s entire rail network”
Developed in partnership with Network Rail under a 25-year contract awarded in 2021, Cellnex reports its infrastructure represents a major engineering achievement, bringing seamless connectivity to a route long challenged by deep cuttings, long tunnels and Victorian-era station infrastructure.
Once fully activated, the shared infrastructure will deliver high speed connectivity across 99 per cent of the 108km route, drastically reducing historical “not-spots” and ensuring passengers enjoy reliable calls, uninterrupted streaming and stable app performance throughout their journey.
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“Passengers on the Brighton Main Line deserve connectivity that matches the importance of this route, and our long-term partnership with Cellnex is transforming what has historically been one of the most technically demanding corridors for mobile coverage into a showcase for modern railway connectivity,” said Paul Richmond, head of business development for Network Rail.
“A huge amount of collaboration has gone into this project over the last few years to support the infrastructure for this project on a railway that is constantly operational. With O2 now on board, even more passengers will soon experience the benefits of this investment every time they travel.”
As a neutral host provider, Cellnex designed, planned, and built this infrastructure, enabling all UK mobile network operators (MNOs) to access shared connectivity, reducing capital investment, lowering cost per megabyte and minimising environmental impact. With the infrastructure now in place, Cellnex is actively working to expand MNO participation, with the ambition that every passenger, regardless of their network, can benefit from enhanced connectivity along the Brighton Main Line.
“A huge amount of collaboration has gone into this project over the last few years to support the infrastructure for this project on a railway that is constantly operational”
“Regular railway passengers will understand the frustration of losing signal mid-conversation or spending whole journeys with buffering videos. With O2 now on board, many more passengers are going to notice the difference on one of the UK’s most important commuter routes,” said Steve Cray, managing director of Cellnex UK.
“This collaboration stands as one of the most significant end-to-end telecommunications infrastructure deployments in British railway so far, and we are proud to be setting a new standard for the UK’s entire rail network.”
The three-year build programme has seen more than 129,000 working hours delivered across more than 11,000 worker entries on the line side and at stations. The infrastructure deployed by Cellnex includes 130km of high-capacity fibre, four Base Station Hotels to host MNO equipment, 39 distributed antenna systems (DAS) within tunnels and along trackside locations, a dedicated station DAS at London Bridge, London Victoria and Clapham Junction, and 16 macro sites along the railway route.
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How will shared neutral-host infrastructure enable multi-operator 5G coverage?What engineering solutions address tunnel signal loss on the Brighton Main Line?How will passenger experience metrics be measured post-deployment?What operational processes minimize disruption during the three-year build?How does shared infrastructure reduce environmental impact and capital costs?
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