As the rollout of 5G networks gets underway on the ground, another dimension of the cellular network is gaining momentum: so-called non-fixed 5G. That is, non-terrestrial technology that can expand mobile coverage into areas where fibre-optic cables and cellphone towers aren’t viable.
Non-fixed 5G promises to end mobile dead zones and to usher in the age of ‘connectivity absolutely everywhere’. But most notably, it should also enable businesses to reap the benefits of the network in some unexpected places.
The UK government, which has had problems with the terrestrial 5G rollout, is getting behind the technology too. In February, the Secretary of State for the Department for Energy Security and Net Zero, Grant Shapps, announced government funding for various projects to encourage new green technology, one of which is to develop a 5G network at sea. In January, the UK Space Agency announced £50m for projects to “supercharge the UK’s satellite communications industry”.
The company building the offshore 5G network, JET Connectivity, is developing buoy platforms which are equipped with 5G comms and can withstand waves of up to 18 metres. Twelve strategically placed buoys can create a 5G network that connects four wind farms over a radius of 800km.
Mobile operators can use it to extend their coverage where it might not make sense to put a tower because it’s too costly or the terrain is difficult
Such a capability would be particularly useful for the rapidly growing UK offshore wind farm sector for construction projects. Workers on the turbines would have reliable connectivity for use in high-speed communications instead of relying on the accompanying vessel, which typically uses satellite comms.
Beyond this, the company hopes to be able to offer real-time data profiling on metrics such as wind speeds, as well as site feasibility studies – for which it already has a contract with Scottish Power. A floating 5G network could even support smart blades capable of predicting parts fatigue before faults develop, says Sam Strivens, senior manager of the floating offshore wind team at the Carbon Trust.
A space-based solution
The idea of a non-terrestrial comms network is piquing the interest of other companies too, says Dr Derek Long, head of telecoms and mobile at technology consultancy Cambridge Consultants. He explains that the focus so far has mainly been on low Earth orbit (LEO) satellites, inspired by Elon Musk’s Starlink.
One of the barriers to uptake has been that standard mobile phones mostly cannot receive LEO satellite comms, which instead require another device with a bigger antenna. But this is a technological problem which US-based AST SpaceMobile says it has solved. The company has a specially designed 64 square-metre satellite in low Earth orbit – the largest communications array deployed commercially, it says – which can provide 4G or 5G to smartphones, without modifications. It plans to demonstrate the capability later this year.
The satellite works like a mobile phone tower, dropping traffic back down to a central hub. It collects solar power on one side and on the other has more than 100,000 individual antenna elements to ping signals back to earth. One satellite can transmit from 700km away to an area the size of Spain, and just 100 would be needed to cover the globe.
AST’s CTO and treasurer Scott Wisniewski says that the company, which has contracts with more than 30 agreements and understandings with major mobile network providers globally, including Vodaphone and AT&T, wants to tap into the trillion-dollar mobile market. “Mobile operators can use it to extend their coverage where it might not make sense to put a tower because it’s too costly or the terrain is difficult or distant.” In that way, this tech may have more use in regions with challenging geography or remote communities, such as in Africa or South America, he says.
That said, operators aren’t ruling out the idea of extending non-terrestrial operations to Europe. At Mobile World Congress last month, a Vodafone executive said that AST’s technology will enable it to increase its coverage in Spain from 75% to 95%.
Starlink is also making moves in this direction. It has unveiled plans to partner with T-Mobile to provide mobile customers in the US with SMS capability where there’s currently no connectivity, by the end of this year.
Why thinking small could hold the answer
And satellites aren’t the only solution. Other technologies emerging to target mobile dead zones – which account for between 13% and 20% of the UK’s landmass as far as 4G outdoor coverage is concerned – include high-altitude platforms, drones and balloons, all operating much closer to Earth than satellites.
A high-altitude system could be flown to the location to provide temporary coverage
Cambridge-based Stratospheric Platforms, which recently raised £70m from investors, has developed a hydrogen-powered drone for this purpose. With the wingspan of a Boeing 787 Dreamliner, the drone can circulate the stratosphere – the second layer of Earth’s atmosphere – to beam internet down to hard-to-reach rural areas. The company claims one drone could replace 450 traditional phone masts.
Long believes that these technologies could be useful for covering large areas that have a high-capacity need, such as at ports where thousands of containers are all relaying information about their identity, location and status. Equally, these solutions could help at music festivals, which have temporary but high-capacity needs. “A high-altitude system could be flown to the location to provide temporary coverage, instead of needing to spend weeks or months establishing a connection on the ground,” he explains.
Smaller drones could do similar things too, but they would likely cover a much smaller geographical footprint. Virgin Media is currently running 5G drone trials in Snowdonia, for example, to explore how to provide support to the emergency services there.
One expert at strategy consultancy Altman Solon says that there could be a complementary role for non-fixed 5G technologies, possibly acting as redundancy to terrestrial solutions for critical applications. But they add that developers will need to act quickly to roll them out ahead of mobile network operators.
On this front, the small size of the UK market could prove prohibitive, notes Long. “American and European companies exist in markets significantly larger than the UK, meaning any investment there will instantly get a higher return because of the larger addressable market,” he says. That will certainly be something for investors and the government to watch out for as this technology takes shape.
