Interferometric synthetic aperture radar (InSAR) is a critical sensing modality for many Earth science investigations. Perhaps most notably, single-pass InSAR has the capability of addressing key gaps identified in the study of the Earth’s Surface Topography and Vegetation (STV). When paired with the emerging category of stratospheric platforms (high-altitude pseudo satellites, or HAPS), an InSAR system provides a new measurement capability able to address the most stringent horizontal, vertical, and revisit aspirations for bare surface topography, water surface topography, and vegetation structure.
With significant support from ESTO, Aloft Sensing, Inc. (Aloft) has developed an InSAR sensor small enough to be accommodated on the lightest of stratospheric HAPS vehicles, yet exceptionally capable. Aloft’s X-band Radar (AXR) system is enabled by Aloft’s patented, ultra-precise Position, Navigation, and Timing algorithms (AloftPNT), allowing InSAR coherency to be maintained over long temporal and spatial apertures, including multiple distributed platforms. The combination of our unique sensor, AloftPNT, and emerging HAPS vehicle capabilities enables the only realizable, single measurement methodology to satisfy simultaneously the most stringent accuracy, resolution, and revisit requirements.
In this talk, we present results from recent stratospheric and airborne measurement campaigns conducted under our NASA ESTO DSI-24 project, including what we believe are the first single-pass InSAR terrain measurements obtained from the stratosphere. We also review our plans for upcoming demonstrations, including distributed multi-platform configurations.