Abstract
Aloft Sensing, Inc. (Aloft) is developing a breakthrough compact radar
system for deployment on high-altitude long-endurance (HALE)
stratospheric platforms. These emerging platforms offer the unmatched
ability to persistently observe science targets and capture the dynamics
of rapidly evolving surface vegetation and topographic phenomena.
Aloft’s radar system is specifically designed to overcome the challenges
associated with synthetic aperture radar (SAR) and interferometric SAR
(InSAR) operation from these platforms in the stratosphere, maintaining
coherence over the minutes-long collection apertures and tolerating the
non-linear flight trajectories to generate high-quality imaging and
interferometric products. The large fractional bandwidth of Aloft’s
radar system, combined with innovative motion compensation techniques,
enable high-precision repeat-pass interferograms to be generated despite
the coarse trajectory control of HALE platforms. Furthermore, Aloft’s
patent-pending positioning, navigation, and timing (PNT) technique
supports coherent multistatic operations, such that a new type of
cross-platform interferometric and volumetric radar products is
possible. This presentation describes the current state of Aloft’s
payload development and demonstrates, via system performance models,
that millimetric surface changes, centimetric topography, and decametric
volumetric resolutions can be obtained from this 7 kg HALE radar system.