Electrodynamic analysis of a microstrip line on a substrate with a gradient of the permittivity

A version is proposed of the electrodynamic analysis of a microstrip transmission line on a substrate with a gradient of the permittivity. The method of straight lines is applied for calculations. The structure is discretized in the transverse direction bath equidistantly and nonequidistantly. Testing the program shows that the results are in close agreement with those obtained by other methods. The algorithm is applied to the numerical evaluation of the influence of inhomogeneity of the dielectric substrate under the conductor close to its edges and in the domain outside the conductor on the dispersion characteristics of the transmission line.