NASA-funded Compact Radar Drives Big Changes in Airborne and Suborbital Radar Capabilities

A collaboration between NASA and the detection of Small Business Aloft has produced a new compact radar system that will allow researchers to take advantage of long-term high-altitude platforms (Hale) to observe dynamic earth systems. This new radar is small, provides very sensitive measures and does not require GPS for positioning; Finally, it could be used on vehicles in space.

Long before a volcano broke out or a mountainous snowy mantle disappears, changes to the millimeters of the earth surface indicate that larger geological processes are at work. But the detection of these tiny changes, which can serve as early warnings to imminent disasters, is difficult.

With the support of the Earth Science Technology Office (ESTO) of NASA, a team of researchers from Small Aerospace Company Aloft Sensing develops a compact radar instrument to observe the surface deformation of the earth, topography and vegetation with unprecedented precision.

Their project, “Hale Insar”, has demonstrated the feasibility of the use of high altitude vehicles (Hale) equipped with an interferometric synthetic opening radar (Insar) to observe surface deformation changes a few millimeters in size and land information with centimeter vertical precision.

“It is a level of sensitivity that has escaped traditional radar sensors, without making them bulky and expensive,” said Lauren Wye, CEO of Aloft Sensing and principal researcher for Hale Insar.

Hale vehicles are light aircraft designed to stay in the air for long periods, from weeks to months and even years. These vehicles can review a scene several times per hour, which makes them ideal to locate subtle changes in the geological environment of a region.

Insar, a remote sensing technique that compares several images of the same scene to detect changes in the surface topography or determine the structure, is also only well suited to locate these indices. But traditional insar instruments are generally too large to fly aboard Hale vehicles.

Hale Insar is different. The instrument is compact sufficiently for a variety of Hale vehicles, weighing less than 15 pounds (seven kilograms) and consuming less than 300 watts of power, about as much energy as it takes to supply an electric bicycle.

Hale Insar operates NASA technologies previously funded to make such detailed measures from a small platform: a new electronically oriented antenna and advanced positioning algorithms integrated into a transmitter-receiver defined by agile software. These technologies were developed as part of the Esto Instruments incubation program (IIP) and the decadal survey incubation program (DSI), respectively.

“All the design features that we have integrated into the instrument are starting to present themselves and to emphasize why this particular payload is distinct from what other small radars could seek to make,” said Wye.

One of these features is a flat table antenna in the flat phase, which gives users the possibility of concentrating the Hale Insar radar beam without physically moving the instrument. Using a panel on the size of a tablet computer, operators can direct the beam electronically, eliminating the need for gamins and other heavy components, allowing the reduced size and weight of the instrument.

“SAR must look to the side. Our instrument can be mounted directly downwards, but look to the left and right on all other impulses so that we collect a left SAR image and a SAR image with the right aspect essentially simultaneously.

Using advanced positioning algorithms, Hale Insar also has the unique ability to locate itself without GPS, based rather on the comments of its own radar signals to determine its even more precise position. Brian Pollard, chief engineer of the Aloft and co-researcher detection for Hale Insar, explained that the precise positioning is essential to create high resolution data on surface deformation and topography.

“SAR is like a long exposure camera, except with radio waves. Your exposure time could last a minute or two long, so you can imagine how many macultes happens if you don’t know exactly where the radar is,” said Pollard.

Navigation without GPS also makes Hale Insar ideal for field missions in austere environments where reliable GPS signals can be unavailable, increasing the usefulness of the instrument for national security applications and scientific missions in distant places.

The Aloft detection team recently reached several key stages, validating its instrument aboard an airship at 65,000 feet as well as small stratospheric balls. Then they will test Hale Insar aboard a plane hale with fixed wings. A future version of their instrument could even find its way in a low terrestrial orbit on a small satellite.

Wye attributes NASA support to help her business transform a prototype into a proven instrument.

“This technology was critical of Esto, and the benefit for science and civil applications is enormous,” said Wye. “It also illustrates the double use potential rendered in place by the research funded by NASA. We note an important military interest in this ability now that it reaches maturity. As a small business, we need this hand approach in hand to be able to succeed. ”

For more information on the opportunities to work with NASA to develop new earth observation technologies, visit Esto.nasa.gov.

For more details, see the entry of this project on NASA Techport.

Project place: Dr. Lauren Wye, CEO, Aloft Sensing

Sponsor organization: NASA instruments incubation program (IIP)