Recent announcements from aeronautical antenna manufacturers about the development of terminals that will be interoperable with multiorbit satellite constellations suggest a trend toward providing airlines with the flexibility to tap into both existing and future satellite networks for their inflight broadband services without having to invest in separate hardware.

In June electronically-steered antenna (ESA) developer Phasor announced a partnership with Astronics AeroSat to produce scalable, dual-beam ESA-based aeronautical terminals that will operate seamlessly with existing geostationary (GEO) satellites and under-development non-geosynchronous satellites such as low Earth orbit (LEO) constellations.

Astronics AeroSat President Matthew Harrah, on announcing the partnership, said it represented “the next phase of inflight connectivity capability.”

The aim of the agreement is to produce an antenna that is “better than what’s available” to access today’s satellite networks, but is also “well-positioned for tomorrow,” when LEO constellations will be ready to provide inflight broadband services, Phasor Chief Executive David Helfgott tells Aviation Week.

“Our ESA aperture has the ability to be single-beam or dual-beam, so you can have a second, independent beam pointing at a different satellite, which gives all kinds of flexibility,” says Helfgott. “You can look at two satellites at the same time or, with the LEOs, you can do a make-before-break where you track a LEO satellite and create a second channel for a different LEO satellite traveling in a different direction.”

The ability to switch between LEO and GEO satellites gives airlines the flexibility to reap the pole-to-pole coverage and low latency benefits promised by LEO constellation developers such as OneWeb, in addition to accessing the tried and tested GEO satellite-based inflight broadband services commonly in use today.


“When you have lots of capacity in the sky . . . you need a really agile antenna system that can dance between networks,” says Helfgott.

Phasor and Astronics expect the first iteration of their antenna to be certified for aeronautical use at the end of 2019, at which time a second iteration will be launched.

A few days before the Phasor/Astronics announcement, ThinKom Solutions, whose mechanically steered antennas form the basis of Gogo’s 2Ku inflight connectivity service, said its technology is now “fully interoperable” with GEO, LEO and MEO (medium-Earth orbit) satellites.

“The new LEO and MEO satellite networks currently under development have the potential to disrupt the satcom market with inexpensive bandwidth, and offer unique benefits in terms of latency, coverage, throughput and redundancy,” ThinKom Chairman and Chief Technical Officer William Milroy said in a statement announcing the development.

“At the same time, GEO high-throughput satellites represent proven lower-risk technology, but have limitations in terms of high-latitude coverage, lower spectral efficiencies and latency. This presents a dilemma for companies facing multiyear planning cycles for satcom terminal selection. Our position is that users and sellers of aeronautical satellite connectivity should not have to make an either-or choice.”

Milroy tells Aviation Week that an antenna option with “an established GEO base but [which] can grow into LEOs and MEOs when they come along” is “comforting to airlines, who are on the risk-averse side.”


Both Phasor and ThinKom say their interoperable antennas will be lighter and lower-profile than other products on the market, which they say makes them easier to install and more fuel-efficient. ThinKom’s terminal is 3.5 in. tall—6 in. when covered by the radome—while the Phasor antenna, says Helfgott, will be one-third the size and up to 50% lighter.

Another key difference is that the Phasor antenna will be electronically steered, while the ThinKom system is mechanically steered. Milroy believes the mechanical antenna provides more “efficiency benefits” and is less likely to overheat when the aircraft is on the ground in a hot climate. However, Helfgott counters that electronically steered antennas are less prone to mechanical failures because they have fewer moving parts.

But there is skepticism in some quarters about the likelihood that any interoperable antenna would work as reliably with every network as a terminal that has been specifically designed to work with a certain type of satellite.

“The whole Ku, Ka, GEO/LEO/MEO debate is creating a lot of uncertainty for airlines,” says Inmarsat Aviation Senior Vice President of Strategy and Business Development Frederik van Essen. “If you’re choosing this because you want flexibility, that’s good. But, to me, it feels like [airlines are] choosing this because there is a lot of uncertainty about where things are headed.”

Van Essen believes there could be “tradeoffs” with antennas that claim to work with multiple networks, noting: “The risk is that if you go for an antenna that’s supposed to do everything, it could give a lower performance [than a dedicated system that has been designed for a specific network]. That’s the dilemma that people are struggling with.”     

But Phasor’s Helfgott takes issue with this “jack of all trades, master of none” comparison. “Our antenna won’t be able to do everything. It will be frequency-specific,” he says, although there is a “road map” to add Ka-band services to the Ku-band antenna in the future.

“A custom-built antenna on a custom-built network is isolated to that network. It would never be useful in this [interoperable] scenario,” adds Helfgott.