Avionics Digital Edition
Found inFeature

Will LEO Change the Paradigm of IFC Service?

Low earth orbit (LEO) satellite networks have the potential to disrupt in-flight connectivity (IFC).

A revolution is underway in the satellite industry. For decades, the industry has been defined by satellites in Geostationary Orbit (GEO), large satellites that orbit with the rotation of the Earth. But the advent of constellations made up of thousands of satellites in Low-Earth Orbit (LEO) is threatening to upend that paradigm.

These LEO broadband constellations, like SpaceX Starlink, OneWeb, and Telesat Lightspeed, are seeking to bridge the digital divide and connect the unconnected — but they also are looking to change the game for In-Flight Connectivity (IFC) service for airlines.

Brad Grady, a principal analyst for satellite industry research firm NSR, said there will be a number of concerns for airlines whether or not they choose a LEO service, such as area of coverage and the hardware necessary. But the biggest difference from a user perspective with IFC service from LEO vs. GEO will be latency, the time delay in the network.

“The biggest difference on the user experience side is going to be latency. There are plenty of debates as to whether latency matters or not. But that's probably one area that people will see a difference,” Grady said. “I tend to be in the world that it probably doesn't matter as much as folks think. Obviously, if you're doing real-time cloud applications, real-time gaming, highly interactive online services — latency will matter.”

One of the benefits that could be ushered in by LEO-enabled in-flight connectivity is the lower latency and expanded capacity provided to areas with higher numbers of aviation users, such as Chicago O’Hare International Airport, pictured here. Chicago O'Hare

OneWeb and Telesat are pitching their constellations as a perfect match for IFC service because of the amount of capacity the systems will make available, low latency, and global coverage, including over the polar regions. Current GEO systems do not offer coverage over the poles, and they are limited in the amount of capacity they can offer.

Manik Vinnakota, Telesat director of Product and Commercial, said LEO service will enable unlimited streaming and ease of use for corporate applications like VPNs, which can require high amounts of bandwidth and lower latency than what GEO provides. He also points to Telesat Lightspeed’s flexible beams, which will be able to reorient satellite capacity based on demand. This could be useful at a major airport hub, for example.

“A big gap that airlines suffer with GEO is major airports. In Atlanta, New York, or Chicago there can be a number of aircraft taking off or landing. If you want your passengers to start streaming or doing their work as soon as they get in — you can't do that. It gets very congested because there are too many aircraft. That’s what we call a Telesat demand hotspot,” Vinnakota said. “Lightspeed will solve that because we are highly flexible. We will be able to put capacity to serve demand.”

Ben Griffin, OneWeb’s vice president of Mobility for Commercial Aviation, said in an email that OneWeb’s system will offer usable global capacity that will make bandwidth speeds that can’t be delivered today possible.

“Where GEO is restricted by physics and look-angles, LEO can provide excellent line of sight everywhere, all the time – which will result in more consistent performance, regardless of aircraft position and direction – even at low latitudes,” Griffin said. “OneWeb’s LEO services will provide truly global, high performance, low latency IFC to the aviation community – an experience limited only by the users’ imagination rather than the available bandwidth.”

An image taken from the March launch of 36 OneWeb LEO satellites by Arianespace from the Vostochny Cosmodrome in Russia. OneWeb

Telesat Lightspeed’s constellation is in the build phase, and the company is targeting commercial services in the second half of 2023, and full global service in the second half of 2024. OneWeb, which now has 182 satellites in orbit, plans to reach all regions north of 50 degrees latitude by June 2021, and offer global service by the end of 2022.

While both Telesat and OneWeb have specified that aviation is a core target market, SpaceX is focusing on the direct-to-consumer broadband market for its Starlink constellation at first. But the company has also clearly indicated that it wants to move into mobility applications like IFC service.

In March, SpaceX asked the FCC for a blanket license to deploy a variation of its user terminal onto moving platforms like aircraft and vessels. SpaceX said in the filing that its Earth Stations in Motion (ESIMS) are electrically identical to the authorized consumer user terminals, but have mountings that allow them to be installed on vehicles, vessels and aircraft. Then in a recent interview with Avionics sister publication Via Satellite, SpaceX COO Gwynne Shotwell said Starlink will serve the aviation market in three years.

It is unclear how much SpaceX will have to modify its consumer antenna to offer mobility service. There are different approaches to how constellations will offer antennas and terminals to make the most of IFC service from LEO. The “holy grail” of an antenna is an Electronically Steerable Antenna (ESA) that is multi-orbit and multi-beam, meaning that it can electronically scan beams from multiple satellites in multiple orbits at the same time. Various tech providers are currently working on this technology.

OneWeb has a partnership with Satixfy, which is developing such a terminal, complete with antenna and modem. Gidi Klein, a member of Satixfy’s aero team, explained why these antennas will provide optimal LEO IFC service. As the plane is moving, and the satellites are moving, the antenna must track the satellite to have a connection. In a LEO system, as there are many moving satellites, the antenna must rapidly switch off between satellites without losing connection, what is called a make-before-break connection.

OneWeb is developing a new in-flight connectivity terminal with Satixfy UK. Pictured here is a computer generated mockup of what their future prototype IFC terminal will look like. Satixfy UK

“This has to take milliseconds, and this switch happens every minute or every few seconds depending on the LEO system,” Klein said. “You cannot allow your cabin to disconnect from service every couple of minutes. You cannot do it with existing motorized technology, you have to go to an electronic antenna.”

Griffin said that OneWeb intends to have the Satixfy terminal ready for service introduction, but is pursuing other options. “It would be folly to assume that our prospective customers are ready, willing and able to undergo a significant exercise to replace existing hardware with ESAs. We are hard at work considering how the transition can be made easier for our customers and even if there are terminals in the field that, with a modest modification, could operate on our network,” he said.

Telesat has yet to announce a preferred vendor for an ESA antenna, but the operator is also planning to use antennas already available on the market like the ThinKom ThinAir, and gimbal antennas. Telesat has performed tests with these antennas with its Lightspeed demonstration satellites, and Vinnakota said they will work with GEO and LEO with minimal upgrades.

Another player, Phasor, which was known for its work on ESAs, is continuing its work as a subsidiary of South Korean defense firm Hanwha Systems, after its assets were acquired out of bankruptcy. Hanwha Systems has announced its own plans for a 2,000-satellite strong LEO constellation, with aviation as a target market.

A photo from the latest Starlink mission launch posted by SpaceX on May 9.SpaceX

A representative for the subsidiary, now Hanwha Phasor, said in an email to Avionics that it has moved beyond technology demonstrations and is testing the commercial flat panel antenna as a full pre-production system prototype. Hanwha Phasor will also not be limited to serving the Hanwha constellation. The representative said the company is actively seeking partnerships with other businesses and plans to offer a wide range of options to service providers and enterprise organizations.

Yet even if the holy grail of a flat panel, electronically steered antenna is available, the business model may remain a challenge for airlines as customers expect greater connectivity but are unwilling to pay for it. The satellite players said that better IFC service delivered by LEO can be offered in a tiered pricing model, or as a loyalty perk. OneWeb pointed to the benefits for crew connectivity as well, which may give airlines another way to justify the cost.

Grady of NSR said that LEO models may give way to third party partnerships, in which a company like Fortnite, Minecraft, or a real-time chat application, partners with an airline to pay for the LEO service to promote their offering.

“LEO does bring in maybe Fortnite or Minecraft, or one of those gaming services to come in and sponsor this,” he said. “Something that's more latency sensitive, where they would never in a million years go on a GEO connection, but maybe with this low latency LEO, they're willing to partner.”

Overall, Grady said that airlines will have to weigh their needs when it comes to route map, fleet structure, cost profile, and customer base, when deciding between a LEO or GEO service. He doesn’t believe that LEO will change the paradigm overnight, pointing to the inertia behind current GEO operators. LEO may not make sense on short-haul domestic flights, but it may be a great offering for routes over the poles, wide body long-haul flights, and government aero transport like Air Force One.

“We’re seeing the airlines are in the driver's seat more and more,” Grady said. “They’re getting very savvy and understanding what's going on their aircraft in terms of the antennas and modems, and what those limits mean for their guest experience. That's an area where the satellite sector needs to start giving a lot more weight. It ultimately all comes down to creating that differentiated guest experience, because that's how airlines keep passengers flying, keep them loyal, and spending with that particular airline.”