Inmarsat to launch small satellite network

Inmarsat, the largest satellite operator by revenue in the UK, is getting into the small spacecraft rush.

It says it will launch about 150 satellites into low-Earth orbit to augment its existing telecommunications services.

These services - phone and data links to ships, planes and other users on the move - are currently provided by big spacecraft at 36,000km in altitude.

The company also wants to spread its activity into 5G on the ground.

It's calling the new architecture "Orchestra".

"An orchestra brings different instruments together, each supporting the other and playing its role in the masterpiece. We're building Orchestra on the same concept," said Rajeev Suri, CEO of Inmarsat.

"By combining the distinct qualities of (Geostationary Orbit) GEO, LEO and 5G into a single network, we will deliver a service that is far greater than the sum of its parts. Our customers will benefit from dramatically expanded high-throughput services around the world."

The idea is that heavy shipping lanes or crowded flight corridors would benefit from the extra bandwidth that LEO satellites could provide. And once those ships or planes are near, or have reached, their destinations, they could also plug seamlessly into terrestrial networks.

Inmarsat has long been associated with some of the biggest commercial telecommunications satellites ever put in orbit. These are behemoths that can weigh over six tonnes at launch.

But the space telecommunications market is changing. There is a rush to low-cost platforms that weigh in the few hundred kilos class.

These satellites are being placed much lower in the sky (under 1,500km altitude) to reduce the delay, or latency, that voice and data traffic experiences as it passes over computer networks. The lower altitude does, however, require many more nodes in the system - hence, the thousands of satellites now being launched by new operators such as SpaceX Starlink and OneWeb.

Inmarsat says it is not trying to compete directly with these incoming internet broadband providers, which seem quite focused, directly or indirectly, on consumers.

Rather, it is looking to modernise and cement its existing position in the mobility market. It will continue to concentrate its business on the maritime, aviation, broadcast, and government/military sectors.

Inmarsat says it will spend $100m in the initial 5-year phase of the Orchestra project. The 150 to 175 new satellites in the LEO network will not come into operation until the second half of this decade.

The 5G activity will happen much quicker, in the next two-to-three years.

Inmarsat already works closely with Deutsche Telekom to provide connectivity on shorthaul flights in Europe, but Orchestra will see the satellite company install mini-5G networks around known shipping hotspots, such as major canals.

It envisions one ship in reach of a 5G connection being able to bounce the connection to another vessel still not in view of the terrestrial network.

"Orchestra is going to open up new use-cases for us," said Rajeev Suri.

"Think about autonomous vessels; secure private networks for government, for emergency, for humanitarian aid; think about segregated VPN for aircraft; and think about cloud-based application ecosystems, etc. So, there are a number of things that we can do with our current base customers, and then there are also a number of applications we can get into where we don't operate presently," he told BBC News.

The new announcement comes as Inmarsat is already engaged in upgrading and expanding its geostationary satellite fleets. It plans to launch a new series of spacecraft that transmits in its traditional L-band frequency, but also can transmit in the higher-frequency Ka-band that its GlobalXpress (GX) satellites use.

In addition, two GX spacecraft are planned to go into highly elliptical polar orbits, specifically so they can serve ships crossing the Arctic Ocean.