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Inversion of multi-frequency experimental data using an adaptive multiscale approach

In this contribution, an adaptive multiscale approach for the reconstruction of objects from multi-frequency microwave laboratory-controlled data is proposed. The considered coarse-to-fine iterative strategy based on spline pyramids enables us to reduce the number of elements to be estimated and, consequently, the number of degrees of freedom in the unknown profile. The robustness of the inversion is increased as well as the quality reconstruction. The procedure consists of sequences of non-linear inversions separated by refinement steps, which overall produces an accurate, low-order representation of the sought object. The main goal of this paper is to test a newly designed adaptive multiscale algorithm against the new experimental data (obtained from inhomogeneous targets) from Institut Fresnel (Marseille, France).