Distributed Radar Interferometry and Tomography Using Clusters of Smallsats

Earth science benefits tremendously from spaceborne synthetic aperture radar. By combining multiple images taken from different angles, we can create accurate digital elevation models and high-resolution tomograms that unveil the three-dimensional structure of vegetation, ice, and dry soil. Whereas today such images are acquired sequentially with conventional satellites, compromising product quality and hindering the monitoring of fast dynamics, DRITUCS envisions distributed sensor concepts to acquire all data in a single pass, paving the way for effective and powerful monitoring of our planet. We exploit clusters of smallsats and build high-quality products from noisy and undersampled data. This makes a key contribution to multi-dimensional imaging theory and represents a paradigm shift from state-of-the-art techniques that demand expensive, high-quality imagery to create digital elevation models and tomograms. Smallsats can be mass-manufactured and lead to low-cost solutions. They are a disruptive NewSpace technology that needs to be complemented by novel distributed approaches to replace and enhance large aperture, high power radar systems. We are pursuing three scientific paths to lay the foundations of a) distributed multi-baseline interferometry, b) distributed tomography, and c) multiple-input multiple-output tomography that takes advantage of waveform diversity to infer unique information about different scattering mechanisms in natural and man-made environments. The elaboration of theoretical models and the development of signal processing algorithms will be complemented by experimental demonstrations with drones. DRITUCS is a giant leap for radar remote sensing with a significant impact on numerous applications. It will pose the basis for future advanced Earth observation missions that will offer remarkable societal benefits and boost European capabilities in the emerging NewSpace sector.