CAD models for microstrip on iso/anisotropic substrates and their application to transient analysis

This article presents the derivation of an analytical equation for the equivalent dielectric constant of a microstrip on an anisotropic substrate. Unlike previous methods, this approach does not require the evaluation of Green's function or finite element analysis. The equivalent dielectric constant, together with an empirically derived dispersion equation, predicts the phase velocity to within 1% of the rigorous full‐wave solution. The use of the model is demonstrated by the analysis of a rectangular pulse propagation along a 50‐Ω microstrip on a Sapphire substrate.