CAD models for a boxed coplanar waveguide with multilayered substrates and overlays

By the conformal mapping method, CAD-oriented analytical closed-form expressions for the quasi-TEM parameters for a boxed coplanar waveguide (BCPW) with multilayered substrates and overlays are presented. The parameters include the effective dielectric constant, the characteristic impedance, the wavelength of the guided wave, and the capacitance per unit length. All of the formulas obtained in this paper are simple and accurate enough for microwave circuits' designs and are useful for transmission line theory.