FIGURE S10. The surface reconstructed by a graph-cut- FIGURE S11. The ground truth built from data provided by the French National Institute of Geographic and Forest Information and Google Earth. based method, alternating 3D reconstruction and surface segmentation. COORDINATE SYSTEMS FOR SYNTHETIC APERTURE RADAR TOMOGRAPHY Several coordinate systems can be used in synthetic aperture radar tomography (Figures S12-S15). z h age er Im Mast Range Cells r x Ra ys x z im uth Az x h Ra da rF r r am e Grou nd Fr ame y r FIGURE S14. In radar geometry, buildings are distorted, and voxel neighborhoods are not isotropic. Grou nd FIGURE S12. An overview of the system. z z Rays Rays Range Cells Ray y 18 FIGURE S13. In ground geometry, the neighborhood is FIGURE S15. In ray geometry, only one scatterer is seen along isotropic. each ray. IEEE GEOSCIENCE AND REMOTE SENSING MAGAZINE JUNE 2020