Demonstration of Spaceborne L-Band Forest SAR Tomography With SAOCOM

In this article, we present a first demonstration of spaceborne L-band synthetic aperture radar (SAR) tomography over a forested scenario. To this aim, we process a Satélite Argentino de Observación Con Microondas (SAOCOM) stack of nine acquisitions with across-track baselines theoretically achieving a vertical resolution around 22 m. To obtain a correct SAR tomography (TomoSAR) imaging, we phase calibrate the stack by properly accounting for forest volumetric structure, which drives the choice of calibrating with smaller baselines. Finally, we ground steer calibrated TomoSAR to achieve a consistent reconstruction of forest structure above ground and derive a forest height map. Comparison with reference canopy height gives a very good overall agreement, proving the effectiveness of our approach and making the experiment an interesting test bed in view of future long-wavelength SAR missions.