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This paper presents a new modeling method to determine the harmonic eddy-current (EC) field induced in a non-ferrous metal and its corresponding magnetic flux density (MFD) by an EC-based sensing system for geometrical measurements, which accounts for the boundary effects of the object. Modeled using a distributed current source (DCS) method in state-space representation, the EC field is formulated as a two-step constrained least-square (CLS) problem to solve for its real and imaginary parts. Two practical techniques to improve the efficiency and accuracy of the EC solutions are illustrated; the first refines the DCS distribution based on the skin-depth effects, and the second takes advantages of commercial mesh-generation software to facilitate the modeling of EC induced in complex shaped objects. The DCS-based EC models are verified numerically by comparing computed results with 2D analytical axisymmetric solutions and commercial finite-element analysis (FEA), and evaluated experimentally with an EC sensor that measures the MFD generated by the induced EC in different materials and geometrical configurations.