Telecom satellites in geostationary orbit usually weigh thousands of kilograms. Companies like Astranis are designing geostationary communications satellites weighing hundreds of kilograms. Credit: Astranis
For a satellite industry torn between traditional geostationary comsats and LEO megaconstellations, GEO smallsats are emerging as a happy medium
This article originally appeared in the May 6, 2019 issue of SpaceNews magazine.
When Swedish broadband service provider Ovzon began shopping around for a small communications satellite that would work in geostationary orbit, the designs that satellite manufacturers trotted out weren’t exactly “small.”
“The ‘small’ was around four tons,” Per Wahlberg, Ovzon’s chief executive, recalled. “That’s not small.”
Ovzon currently uses leased satellite capacity to deliver a 60/20 megabits-per-second internet service to far-flung government, defense, media and NGO customers it equips with ultra-portable terminals. Wahlberg said he began searching a decade ago for a satellite that wasn’t so big that its capacity and coverage area demanded a business plan for expanding well beyond the parts of Africa, Asia and Europe it currently serves.
“When they said small, it was like when you go to McDonald’s and order a small Coca-Cola,” he said.
Only recently did anything truly “small” become available, Wahlberg said. The company’s first dedicated satellite, dubbed Ovzon-3, is expected to tactfully widen Ovzon’s coverage areas while at minimum quadrupling the internet speeds it can offer.
John Gedmark, CEO and co-founder of small GEO builder and operator Astranis, asked a similar question when he saw remote sensing startups packing cameras into small satellites and revolutionizing their corner of the space industry.
“We saw that start to be proven out with companies like Skybox for Earth imagery, and we realized that there was this gap: no one was taking this approach to telecommunications,” he said.
Gedmark and others say the technology needed to make small GEO satellites viable has only become available very recently.
“Power is always the No. 1 problem you have in space,” said Marc Bell, chairman of Terran Orbital, the company building the GapSat-1 small GEO satellite for Hong Kong-based GapSat. “Now with things getting more efficient from a power standpoint, it gives you more options.”
“Some of them have been a long time coming,” Gedmark said of the essential tech breakthroughs. “Things like increased power density in lithium-ion batteries, electric propulsion, which is very mature now, and importantly for us, software-defined radios.”
Changing up the tempo
Ovzon, Astranis and GapSat all started small GEO projects a few months apart within the past nine months. Ovzon ordered Ovzon-3 in December from Space Systems Loral — a satellite Wahlberg said will be around 1,000 kilograms. SpaceX has a contract to launch the satellite on a Falcon Heavy rocket in 2021 (Wahlberg said the launch provides a “cost effective direct injection” into geostationary orbit, justifying the use of the large vehicle).
Astranis is building an unnamed 300-kilogram satellite it will operate following a 2020 launch with a to-be-announced provider.
Astranis’ approach to geostationary telecommunications uses spacecraft less than five percent the mass of an Intelsat EpicNG satellite. Credit: Astranis
GapSat, a company founded by satellite industry veterans in 2014 to match underutilized satellites with operators in need of short-term capacity, hasn’t stated the mass of the satellite but says its small size and low cost mean it should be able to fill up all its capacity with customers quicker than a traditional multiton geostationary satellite.
Astranis and Ovzon plan to provide broadband services using small GEO satellites that can serve customers more responsively than traditional large satellites. GapSat CEO Gregg Daffner did not respond to repeated requests for comment about GapSat’s plans.
Communications satellite operators around the world are increasingly focused on broadband as the next major opportunity, but not everyone agrees on the best approach.
As a business with deep roots in broadcast television, commercial satellite operators are accustomed to launching truck-sized spacecraft into geostationary orbit where they will spend 15 to 20 years relaying TV channels to cable and broadcast networks. Satellite operators traditionally have enjoyed enviable profit margins once they’ve amortized the expense of putting up such large, long-lived satellites.
Television broadcasting remains the cornerstone of most satellite operator business plans, often counting for half or more of their revenue, but the biggest new growth opportunities are in broadband.
Some 3.9 billion people — more than half the world’s population — logged on to the internet last year, according to the International Telecommunication Union. Six in 10 households had internet access in 2018, up from fewer than two in 10 in 2005, according to the United Nations entity.
And average bandwidth use — driven in part by video’s growing share of internet traffic and the increasing number of connected devices per user — is on the rise. Computer networking giant Cisco predicted last year that global internet traffic will nearly triple by 2022, averaging 85 gigabytes per user per month. (In North America, where monthly internet traffic averaged 94 gigabytes per user in 2017, monthly usage is expected to top 260 gigabytes by 2022).
Satellite operators are increasingly worried that the old way of business won’t work for broadband, particularly because of this scaling usage pattern. A satellite that lasts for 15 years or more risks obsolescence before retiring as customers grow more bandwidth-intensive.
Broadband distributors and enterprise customers also don’t typically sign massive “anchor” contracts for a decade or more worth of capacity the way broadcasters have historically done, making the business case for internet-capable high-throughput satellites more difficult.
“Unless you have some really solid contracts up front, you have to build [backlog] from the ground up,” said Chris Baugh, president of the consulting firm Northern Sky Research. “It’s not like the old days where you flip the switch and 70 percent of your satellite is full.”
Many operators are introducing hybrid satellites that carry both traditional wide beam payloads for television broadcasting and high-throughput spot-beam payloads for broadband. Norwegian fleet operator Telenor is an example with its Thor-7 satellite, as are Telesat and APT satellite with their Telstar-18 Vantage/ Apstar-5C satellite.
Ovzon says having a smaller satellite in GEO means it can hone power into smaller, more powerful beams. Stronger beams means user terminals on the ground don’t have to be as big to acquire the satellite’s signal. Credit: Ovzon
Some operators, like Hughes, Eutelsat, Inmarsat and Viasat, are investing in pure broadband systems to serve mobile platforms ranging from commercial ships to military drones as well as a mix of households and enterprises beyond the reach of cable and public Wi-Fi. These operators are banking on the scale and power of so-called very high throughput satellites to drive down the cost to deliver each megabit.
Other companies, like OneWeb, SpaceX and Telesat, are preparing hundreds or thousands of smaller satellites bound for low Earth orbit to deliver high-speed, low-latency internet to underserved parts of the planet.
Why smallsats in GEO?
Small GEO operators are trying to pair the advantages of smallsats, such as their lower cost, faster build times and potentially shorter design life, with the consistent coverage geostationary orbit provides. A third of the planet is visible to a single satellite in geostationary orbit 36,000 kilometers above the equator, in contrast to the dozens or hundreds needed for continuous coverage from low Earth orbit satellite systems.
Small GEO satellites are enabling companies to build viable business plans around serving smaller markets than could be justified with a larger, more expensive satellite. Astranis’ satellite will focus solely on Alaska, the largest and most sparsely populated U.S. state.
Alaskan telecommunications services provider Pacific Dataport is Astranis’ biggest customer, having signed a multiyear capacity contract in January. Astranis’ first satellite, with a capacity of 7.5 gigabits per second, will more than triple the capacity currently over Alaska, according to Astranis.
For Ovzon, the small GEO approach is an economical way to concentrate the satellite’s capacity over a small area with high power levels, Wahlberg said. Those high-power beams on the satellite mean customers can use smaller terminals on the ground, he said.
“Our aim is to close a link using very small antennas on the ground, so it is important that we have a lot of energy in the signals we send,” Wahlberg said.
Ovzon anticipates its Ovzon-3 satellite, like traditional GEO communications satellites, will last at least 15 years. Astranis, however, expects its satellites to last seven years before replacing them with newer, updated models.
“If you are going for a faster refresh rate, then you have to find every way you can to go lower costs, and to be more nimble,” Gedmark said. “To us that meant small satellites, and small satellites in GEO.”
More to come?
Gedmark said Astranis sees no upper limit to how many small GEO satellites it could operate. Demand exists to support “many dozens” of satellites. And, thanks to advances in software-defined radios, Astranis can place multiple satellites in the same orbital slots without causing signal interference, he said.
Per Wahlberg, CEO of Ovzon, a company with six geostationary orbital slots and plans to fill all of them, possibly with small GEOs. Credit: Ovzon
Ovzon has six orbital slots, and anticipates putting a satellite in each one, Wahlberg said.
“When we started this company the view was always to have small GEO platforms, and platforms that are purpose-built to perform a specific task… mobility broadband, in our case,” Wahlberg said.
Terran Orbital’s Bell expects it will take some time before small GEOs become a new norm, but sees progress in that direction.
“I do think that as a trend, as more people get comfortable with the concept that you can do a smallsat in geosynchronous orbit, and … as people develop and utilize better ways to communicate with satellites in space with higher bandwidth rates, I think that will drive the desire to do it,” he said.
Wahlberg didn’t rule out one day operating a bigger satellite, or even sharing a satellite platform with another operator (an approach referred to as a condosat). But he cautioned that the larger the satellite, the more of the Earth it covers, and the more its power gets spread out.
Customers on the edge of a satellite’s coverage wouldn’t have an optimal “look angle,” resulting in a lower quality service, he said.
Astranis customer Pacific Dataport is open to more small GEOs, since it plans to have a larger dedicated Alaskan satellite system in the future, said Bruce Kraselsky, managing director of Space Partnership International, a Bethesda, Maryland-based consulting firm that handled technical and regulatory work for Pacific Dataport.
Kraselsky said Space Partnership International is evaluating large high-throughput satellites and an incremental growth strategy that would involve “multiple smaller satellites along the size of Astranis or slightly larger.”
Chuck Schumann, founder of Pacific Dataport said in a January news release that the company intends to ultimately provide 40 to 50 gigabits per second of dedicated bandwidth to Alaska.
In an interview, Schumann said Pacific Dataport will start service with Astranis offering 25 megabits per second downlinks, and increase that to 100 mbps — the same as Viasat’s top ViaSat-2 offering — as Pacific Dataport orbits more satellite capacity.
And thanks to small GEOs, choices abound for how to do that.
“Because of these technology trends, we have options that people have never had before,” Kraselsky said.
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