LAYER STRIPPING APPROACH TO RECONSTRUCT SHAPE VARIATIONS IN WAVEGUIDES USING LOCALLY RESONANT FREQUENCIES.

This article presents a new method to reconstruct slowly varying width defects in two-dimensional waveguides using one-side section measurements at locally resonant frequencies. At these frequencies, locally resonant modes propagate in the waveguide up to a "cut-off"" position. In this particular point, the local width of the waveguide can be recovered. Given multifrequency data measured on a section of the waveguide, we perform an efficient layer stripping approach to recover, section by section, the shape variations. It provides an L infinity-stable method to reconstruct the width of a slowly monotonous varying waveguide. We validate this method on numerical data and discuss its limits. [ABSTRACT FROM AUTHOR]