Tropical Forest Characterization Using Parametric SAR Tomography at P Band and Low-Dimensional Models

P band synthetic aperture radar (SAR) tomography represents a powerful tool for characterizing the 3-D structure of tropical forests from their electromagnetic response. Current techniques separate the responses of the forest canopy and the underlying ground using SAR tomography, polarimetric diversity, and complex processing techniques. This letter shows that similar performance and better stability may be achieved using single-polarization data and parametric tomographic focusing, performed using a low-dimensional model. The vertical density of reflectivity of a tropical forest is modeled, at P band, using a Dirac function for the ground and a narrow peak for the volume. The performance of the proposed method is evaluated using P band tomographic data acquired during the TropiSAR campaign, and the results show that it can accurately and reliably estimate key structural parameters of the observed topical forest.