TY - JOUR T1 - A Low-Frequency Electromagnetic Near-Field Inverse Problem for a Spherical Scatterer AU - Nikolaos L. Tsitsas JO - Journal of Computational Mathematics VL - 5 SP - 439 EP - 448 PY - 2013 DA - 2013/10 SN - 31 DO - http://doi.org/10.4208/jcm.1304-m4388 UR - https://global-sci.org/intro/article_detail/jcm/9746.html KW - Near-field inverse problems, Low-frequency region, Dipoles, Hypergeometric functions. AB -

The interior low-frequency electromagnetic dipole excitation of a dielectric sphere is utilized as a simplified but realistic model in various biomedical applications. Motivated by these considerations, in this paper, we investigate analytically a near-field inverse scattering problem for the electromagnetic interior dipole excitation of a dielectric sphere. First, we obtain, under the low-frequency assumption, a closed-form approximation of the series of the secondary electric field at the dipole's location. Then, we utilize this derived approximation in the development of a simple inverse medium scattering algorithm determining the sphere's dielectric permittivity. Finally, we present numerical results for a human head model, which demonstrate the accurate determination of the complex permittivity by the developed algorithm.