A study on irregular baseline constellations in SAR tomography

摘要

SAR Tomography (SARTom) is the natural extension of SAR Interferometry (InSAR) to solve for multiple phase centersrnwithin a resolution cell and obtain the 3-dimensional (3D) representation of a scene. In order to obtain a reasonable resolu-rntion and reject ambiguities, a large tomographic aperture sampled with a sufficient number of acquisitions is required. Forrnmost applications this number represents a critical factor. Basically, the reference acquisition geometry usually assumes arnregular sampling of the tomographic aperture. The potential of irregular constellations for SARTom represents a field thatrnhas not yet been completely investigated and could allow one to reduce the number of acquisitions keeping the constraintrnof resolution and ambiguity rejection. In this context, this paper presents a study on how irregular distributions of base-rnlines impact the tomographic reconstruction. In particular, the acquisition geometry will undergo a minimum redundancyrndesign in term of baselines, in order to estimate the elements of the sample covariance matrix. The study is applied onrnsimulated as well as on real data acquired at P-band by the E-SAR system of the German Aerospace Center (DLR).