The race is on for commercial spacebased radar. Since June, four firms have announced plans to build Synthetic Aperture Radar (SAR) satellites to gather Earth observation data in all weather conditions, day and night. Other entrepreneurs are quietly pursuing the same goal.
“There is a general feeling that SAR’s time is about to come,” said Wade Larson, president and chief operating officer for UrtheCast, the Vancouver-based Earth imaging company with two cameras operating on the International Space Station and two satellites in orbit.
All the new SAR constellations are based on the same premise. Growing demand for imagery from electro-optical satellites proves that customers will pay for information. They want to know, for example, how many containers are lined up at distant seaports, see progress on buildings under construction and find out how much oil is stored in tanks around the world.
But most optical systems only show activity occurring between 10 a.m. and 2 p.m. on cloud-free days. “There is a big untapped market of folks who need more reliable data,” said Adam Maher, founder of Ursa Space, a geospatial services company based in Ithaca, New York, that plans to use SAR to serve agriculture, business intelligence, disaster relief and defense markets. Ursa Space has announced few details, but says the company will launch its first space-based radar in “a couple of years,” Maher said.
UrtheCast is working with Surrey Satellite Technology Ltd. to develop technology for eight pairs of satellites, four in sun synchronous orbit and four in medium inclination orbit, to launch around 2020 or 2021. Each pair includes an X-band and L-band space-based radar flying one to two minutes ahead of a satellite equipped with a high-resolution multispectral sensor.
Once the space-based radar detects an object, it will use highspeed onboard processors to make decisions autonomously and cue the trailing optical satellite to focus on the same object. “What you are going to get out of this is very high information content, rich information products,” Larson said.
Iceye, a spinoff from Finland’s Aalto University, plans to begin providing data with a constellation of six SAR satellites focused on Earth’s Arctic regions and build up to a constellation of 50 space-based radars to offer customers the ability to acquire data on any area of the globe within a couple of hours of a request.
“Iceye focuses on speed and reliability,” Pekka Laurila, Iceye chief executive, said by email. “We are making tradeoffs. We won’t be the highest resolution provider, but in markets where timeliness is valuable, we will be the provider that gets you the first image or the highest refresh rate for continuous coverage.”
XpressSAR of Arlington, Virginia, plans to operate four satellites equipped with X-band radars, offering resolutions ranging from less than one meter to 30 meters. “Our focus will be on the cloudprone regions of the world,” said Wolfgang Biedermann, XpressSAR chief executive and former chief executive of Germany’s RapidEye AG, whose constellation of five optical and near-infrared satellites are now operated by San Francisco based Planet Labs. “XpressSAR’s constellation will allow us to provide data and products in large quantities, in short intervals and with short response times,” Biedermann said by email.
Experts trace the recent surge in SAR activity to several factors, including growing demand for Earth observation data, reduced launch costs and miniaturization of electronic components.
The global Earth observation data market, which was worth about $900 million in 2015, is expected to grow at a rate of 7.5 percent annually until 2024, while the market for SAR data rises 10.3 percent per year, said Prateep Basu, an analyst for Northern Sky Research, an international market research and consulting firm based in Cambridge, Massachusetts.
Northern Sky Research expects global security concerns to prompt most of the growth in the SAR market, but thinks that startups planning to launch constellations of small satellites will help drive down the price of radar data, “leading to rise in demand from niche areas like maritime surveillance, climate change studies, precision agriculture and urban planning,” Basu said by email.
Price is a major concern. For decades, civil and military government agencies have relied heavily on space-based radars for applications ranging from maritime surveillance to ice sheet and forest mapping. Those satellites generally weigh hundreds of kilograms and cost hundreds of millions of dollars to build and launch.
“SAR data is useful, but it’s expensive,” said Joe Rothenberg, former NASA associate administrator for spaceflight and currently director of engineering and operations for Terra Bella, the former Skybox Imaging. “The challenge will be to get the cost down.”
Entrepreneurs plan to tackle that challenge by flying radars on small satellites and adopting technology widely used in commercial products like smartphones and tablet computers, said Tomas Svitek, president of Stellar Explorations, an aerospace company based in San Luis Obispo, California that is developing a space-based radar for maritime surveillance in polar regions. Svitek declined to offer further details on the project, which has not been announced.
Still, SAR satellites will never be as cheap as optical satellites, Svitek said. “They can’t be built for $50,000, but I think we can get the cost down to $1 million or $2 million,” he said.
UrtheCast plans to drive down the cost of its fleet with commercial radio-frequency technologies, which it is qualifying for spaceflight. “Instead of customizing and tailoring everything for this particular application, we look at the problem the other way around,” Larson said. “Where have people invested billions or tens of billions of dollars in developing very high speed electronics and how do we build around those?”
Ground truthing a smaller SAR sat
Later this year, Surrey Satellite Technology Ltd. (SSTL) and its partner Airbus Defence and Space plan to launch NovaSAR, a project designed to demonstrate that a small satellite equipped with an S-band synthetic aperture radar can help customers detect ships at sea, observe forests, survey rice crops and monitor floods. SSTL and Airbus have not named a launch provider.
“We’ve worked hard to not create a very expensive satellite that does everything that everybody wants,” said Andrew Cawthorne, SSTL’s head of Earth observation. “Instead the approach has been to target a few specific applications and really design for these.”
Weighing in at 440 kilograms, NovaSAR is a fraction of the size of sophisticated space-based radars built for government agencies, like the German DLR’s 1,230-kilogram TerraSAR-X and 1,330-kilogram TanDEM-X satellites, which provide three dimensional maps of the Earth’s surface.
By using gallium nitride amplifier technology in the payload and relying on heritage avionics from the SSTL-300 satellite bus, SSTL and Airbus have been able to keep costs low. “The main differentiator is the price point,” Cawthorne said by email.
SSTL’s objective is to sell each satellite in a NovaSar constellation for 15 million British pounds per spacecraft. “We’re not there yet for a single spacecraft (and of course the first one is more than that) but we think this is achievable,” Cawthorne said.
When the NovaSAR mission was announced in 2011, it was envisioned as a four-satellite constellation. Now, a single satellite is planned, but SSTL is talking with partners and investors about building additional NovaSAR satellites, Cawthorne said.
In 2011, SSTL’s corporate parent Astrium Satellites and the British government announced plans to split the 42 million British pound cost of the first NovaSAR satellite.