Ground-Based Demonstration of Multiple-Input Multiple-Output Synthetic Aperture Radar Tomography

Synthetic aperture radar (SAR) tomography allows the retrieval of the vertical structure of both natural and urban scenes. However, monostatic (repeat-pass) and multistatic (single-pass) tomography do not guarantee a correct reconstruction of the vertical profile when it comes to double-bounce scattering. Multiple-input multiple-output (MIMO) SAR tomography has the potential to detect and separate the contributions of single- and double-bounce scattering, allowing a more realistic reconstruction of the scene. In particular, beamforming techniques applied to data acquired by a MIMO system allow steering independently and a posteriori the transmit and receive beams in order to scan the scene even for double-bounce scattering geometries. A ground-based MIMO SAR demonstrator has been developed in order to validate the beamforming algorithm and further investigate the behavior of double-bounce scatterers in MIMO SAR tomography. This paper presents the design of the experiment and some preliminary processing results.