Field Coupling to Transmission Line Model Accounting for the Effect of Dielectric Coatings

This article proposed a modified electromagnetic field coupling to transmission line (TL) model with the objective to accounting for the impact of complex dielectric coatings. Classic TL model neglects the perturbation effects of coatings on the incident electric field; the validation of this simplification is disproved in this article for TL structure with complex dielectric coatings. Through analysis, it is corroborated that coating effect could be neglected only for longitudinal electric field component, whereas the perturbation on transverse field component needs to be taken into account by a newly introduced parameter called coating coefficient. The proposed method is verified through a case study on a differential line system, where a simulation method based on the 2-D finite element method is also proposed to evaluate the value of the coating coefficient.