Researchers may soon find it easier to study earthquakes, volcanic eruptions, and other rapidly changing Earth systems, thanks to a new radar instrument.
The “HALE InSAR” is a compact Interferometric Synthetic Aperture Radar (InSAR) system designed for High Altitude, Long Endurance (HALE) platforms, including drones, airships, and balloons. Featuring an advanced electronically steered antenna and a state-of-the-art navigation system, this instrument is set to be one of the smallest and most precise InSAR systems developed for scientific missions.
InSAR technology works by emitting radio signals to detect small deformations in Earth’s surface, capturing surface changes as minor as a millimeter. This capability makes it invaluable for monitoring phenomena such as glacial melting, sea-level rise, and seismic activity.
Currently, no InSAR instruments are compact or lightweight enough for use on HALE platforms, which are designed to fly up to 21 kilometers above the Earth for extended periods. However, HALE InSAR promises to change this. Weighing just seven kilograms and requiring less than 300 watts of power—roughly the amount used by a small electric bike—HALE InSAR could soon be deployed not only on HALE aircraft but also on small, low-orbit satellites.
According to Lauren Wye, CEO of Aloft Sensing, Inc. and Principal Investigator for HALE InSAR, creating such an efficient and compact radar system presented significant challenges.
“All of these stratospheric vehicles are extremely sensitive to mass. The heavier the radar, the larger the vehicle needs to be, which increases launch costs, requires more solar power, and reduces the time available for the radar to operate,” Wye explained.
Wye and her team, which includes researchers from NASA, the United States Geological Survey (USGS), and private sector collaborators, developed several innovative technologies to minimize the instrument’s weight without sacrificing its functionality. These include a flat, electronically steered antenna that provides a broader range of observation and improves aerodynamics, as well as a unique radar-based positioning system.
“We have a patent-pending technique that allows the radar to determine its position with greater accuracy than GPS, all within the radar system itself without needing additional hardware,” Wye said. This positioning capability is key to HALE InSAR’s high measurement precision.
Currently, Wye’s team is finalizing a lab-based prototype of HALE InSAR, which they plan to test on a variety of unmanned HALE platforms, including fixed-wing aircraft and airships. Following successful airborne testing, Wye aims to adapt HALE InSAR for deployment aboard small satellites in low-Earth orbit.
The project is funded by NASA’s Instrument Incubation Program, part of NASA’s Earth Science Technology Office, which has provided crucial support for developing the prototype.
“This funding has been a gateway, giving us the trust and resources to pursue our vision,” Wye said. “NASA ESTO’s backing shows that they believe in our expertise, our mission, and our ability to succeed.”