Cellnex has signed up Three UK as the first retail customer on its network on the London-to-Brighton railway line, and it is clearly keen to add the UK’s other mobile network operators to its passenger list.

The neutral host specialist signed a 25-year contract with Network Rail to provide connectivity on the high-usage Brighton Mainline route almost two years ago. At the time it talked up plans to use the neutral host model to provide targeted coverage and capacity for the the country’s MNOs, but the first deal seems to have been a long time coming.

Nonetheless, Cellnex remains upbeat about the project.

“Cellnex UK’s infrastructure can host equipment from all four MNOs, meaning there is potential for all mobile and smart device users to benefit from enhanced connectivity throughout their journey,” it said on Thursday. No need for any great detective work to unravel the sentiment behind that comment.

For now though, it’s all about Three UK.

It makes sense that Three would be the first to sign up, given the in-depth relationship the companies must have built through the lengthy regulatory process that governed Cellnex’s recent acquisition of UK mobile towers belonging to the telco’s parent company, CK Hutchison. That deal finally closed late last year, incidentally, adding around 5,000 UK towers to Cellnex’s portfolio.

“With our 4G network now covering 99% of the UK outdoor population, carrying 28% of mobile data traffic, together with our partner, Cellnex UK, we are proud to lead the way in extending this to rail routes typically blighted by patchy coverage,” said Three UK and ROI’s Chief Technical Officer, David Hennessy, perhaps hinting at similar deals to come on other rail lines. Cellnex certainly has experience in this area, having brokered similar agreements with railway companies in Italy and Spain, for example.

Cellnex is naturally having to upgrade its infrastructure to support the deal. This will include towers along the railway corridor; the installation of a handful of equipment rooms – or base station hotels, to use its own terminology – close to the railway line to house kit to increase network capacity; high capacity fibre between London and Brighton, specifically from Victoria and London Bridge stations in the capital via East Croydon; and radio equipment to provide coverage in the main London stations and in tunnels and railway cuttings. Newly deployed macro sites and distributed antenna systems (DAS) will host Three UK’s equipment.

The 51-mile Brighton Mainline, plus its branch lines, carry 50,000 passengers per day at their busiest, but connectivity is hugely variable for those passengers. According to Cellnex, some parts of the line boast a strong signal, but others are weaker and there are also black spots of no connectivity. The mobile signal is affected by the topography, as well as the many tunnels and cuttings along the route. Hence the need for a specific railway line infrastructure to even things up.

“The lack of reliable connectivity along complete rail journeys is a frustration shared by many passengers and is something that Network Rail is keen to address. As a neutral host and via shared investments, Cellnex provides value to both mobile operators and Network Rail,” said David Crawford, Managing Director, Cellnex UK. “Therefore, this agreement with Three UK is a hugely positive step in improving Three UK customer experience along the Brighton Mainline route,” he said…doubtless hoping that Three’s rivals are now thinking along similar lines. No pun intended.

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