Interferometric Synthetic Aperture Radar Height Estimation with Multiple Scattering Centers in a Resolution Cell

This thesis investigates the use of Interferometric Synthetic Aperture Radar (IFSAR) processing for three-dimensional (3D) reconstruction of radar images in the presence of multiple scattering centers in a resolution cell. Systems for processing IFSAR data in each resolution cell separately are proposed. The objective of these systems is to reduce the average height error of a reconstructed image with respect to the height error of an image formed by standard IFSAR processing. A model for multiple scattering centers is proposed and used to analyze height error that results from multiple scattering centers in a resolution cell. The problem of reducing height error is then posed as a joint detection and estimation problem. Each resolution cell of an image scene is modeled by a ternary hypothesis model that classifies a resolution cell as having zero, one, or more than one scattering center, and two multiple hypothesis detectors are developed under this model. Each detector is used in a two stage IFSAR height estimation system. The first stage detects the number of scattering centers in a resolution cell from IFSAR data; it then decides to discard the data or to send it to a second stage which performs height estimation. Simulation results of the detection and RMS height error performance of each IFSAR height estimation system are presented along with 3D reconstructions of a computer generated backhoe model.