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Starlink terminals are leading big changes in satellite antenna technology.
Beyond all the new space technologies that break the bonds of Earth, slip through the atmosphere and fly off into the great vacuum beyond, there is another category: boring, but important. Flat-panel antennas are one example.
While SpaceX’s more than 6,000 Starlink satellites circling the globe in low Earth orbit (LEO) get the most attention, it was CEO Elon Musk’s impromptu donation of user terminals to the Ukrainian government in 2022 that helped organize a defense against Russia’s invading army.
- Pentagon wants to connect military and civilian networks
- U.S. Navy is operating Starlink terminals on 60 ships
Two attributes make the Starlink terminal game-changing: the electronically steered antenna’s ability to track fast-moving LEO satellites and its $599 price. Never has a company produced an antenna so capable and cheap—and never has a satellite connection promised so much bandwidth with so little latency.
A host of companies are following SpaceX’s example, starting with Amazon’s Project Kuiper, which boasts the ability to manufacture terminals for $400 each. Other companies can not match SpaceX or Amazon’s consumer-level costs but are making up for it with antennas that promise to connect to satellites in multiple orbits—sometimes from atop a moving vehicle.
The Pentagon has noticed. The U.S. Navy plans soon to issue a request for proposals for a shipboard antenna that can connect to up to 15 different satellite constellations at once, said Bill Joo, special project manager with the Naval Information Warfare Center Pacific, speaking at the Satellite 2024 Conference in Washington on March 19.
The Satellite Terminal (transportable) Non-Geostationary (STtNG) program aims to give ships multiple options for sending and receiving data, allowing sailors to leverage multiple satellites in different orbits for military systems using a single terminal. The electrically steered antenna would transmit on different radio bands simultaneously.
“We’re no longer stuck with one paradigm or another,” Joo said. “We can dial up as many [satellites] as we need to.”
“These satellites will include, eventually, proliferated low-Earth-orbit systems such as SpaceX Starlink and Amazon Kuiper, medium-Earth-orbit systems such as SES O3b Classic and SES mPOWER, highly elliptical orbit systems such as Space Norway Heosat, and inclined geosynchronous-Earth-orbit systems such as Inmarsat-5 military-Ka band satellites,” according to a Small Business Innovation Research contract issued to Bascom Hunter Technologies, which is to manage the request for proposals.
The service wants an antenna that can “operate on any U.S. Navy surface ships, can be cross-decked from one surface ship to another and made operational within days,” the online notice says. STtNG may also operate at Navy shore facilities, and future versions are expected to be used in submarines and aircraft.
This interest in a multiconstellation terminal comes as the Navy is already operating Starlink terminals on 60 ships, including aircraft carriers, Joo noted, though he declined to explain the operational uses of Starlink or STtNG terminals.
Meanwhile, Hawaiian Airlines has begun installing civilian Starlink terminals on the back of its Airbus A321neo airliner fleet and has found the internet latency low enough for passengers to play online first-person shooter video games. Presumably, higher bandwidth and low latency ought to allow the U.S. military to play real-person shooter games.
Indeed, connecting “any sensor to any shooter” is the overarching vision for the Defense Department’s battlefield network, known as Joint All-Domain Command and Control. The backbone of that network is to be the Space Development Agency’s Transport Layer, a military communications network of up to 500 LEO satellites linked in space through laser communications systems. The satellites will transmit back to Earth on the Ka band, Link 16 and the Integrated Broadcast System.
The U.S. Navy wants to connect military and commercial satellite communications networks, Joo explained, pointing to the Defense Innovation Unit’s Hybrid Space Architecture project to do just that.
The service aims to develop “the ability to operate off of any constellation at any time, at any place,” he said. “We want to be able to just operate and not care about how it’s done.”
Multiorbit terminals are one way to connect users to multiple satellite constellations. Several companies have demonstrated antennas capable of connecting to satellites in different orbits, including Hanwha Phasor, Hughes Network Systems and Kymeta.
Kymeta sent its first multiorbit flat-panel satellite antennas to an undisclosed branch of the U.S. military in March. The company’s Osprey u8 HGL is a hybrid terminal that can connect to geostationary (GEO) and LEO satellites as well as cellular towers, and was developed for military users. It carries a OneWeb modem, allowing it to connect to that company’s LEO broadband constellation—even from the top of a moving ground vehicle or ship. The terminal also contains hardware to connect it to GEO satellites and local cellular networks.
Flat panels are getting smaller as the equipment becomes more capable. Kymeta says its Ku-band antenna, which is 80 cm (31.5 in.) wide, was designed and tested to military standard. It based the Osprey on its commercial terminals, manufacturing it on the same production line.
The military antenna connects simultaneously either to a cellular network and GEO satellite or to a cellular network and LEO satellite constellation. The Osprey terminal can switch between satellites in different orbits in milliseconds, Kymeta Senior Product Manager Frank Armstrong said at the Satellite 2024 conference.
Typical military users only require a few megabits of data throughput, he noted—about 5 Mbps download and 2 Mbps upload capacity, a bandwidth requirement that a conventional GEO satellite can handle. OneWeb’s LEO constellation can handle 100 Mbps in downloads and 20 Mbps in uploads.
Armstrong declined to say how military personnel are using that additional data capacity, but noted that LEO and GEO satellites are valued for different operational scenarios.
“They are really not selecting [satellites] according to data rates,” he said. “They are selecting them according to situational parameters.”
For users to connect to LEO satellites, which pass overhead every few minutes, the space above them must remain clear. That tends to be useful for when a vehicle is on the move, Armstrong said. However, if a soldier wanted to hide under a tree canopy, a GEO satellite located in a fixed position closer to the horizon might be preferable, he noted.
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