Nonparametric Array Manifold Calibration for Ice Sheet Sar Tomography

Array manifold calibration improves parametric direction of arrival angle estimator performance by reducing mismatch between the model of the array transfer function and truth. This paper demonstrates the estimation and application of a measured manifold for a multichannel ice penetrating synthetic aperture radar (SAR) used to image subglacial features with tomography. We apply SAR tomography to produce digital elevation models of exposed rock and sea ice in the Canadian Arctic Archipelago using both nominal and measured manifolds in angle estimation. We compare reconstructed topography to a fine resolution satellite-derived digital elevation model of the Arctic and demonstrate improvements realized when a measured manifold is used in 3D image formation.