Accelerated spectral domain approach for shielded microstrip lines by approximating summation with super convergent series

In this paper, a novel accelerated spectral domain approach (SDA) using few basis has been used to obtain very accurate and quick solution for propagation constant (β) for shielded microstrip lines. The convergence of the elements of the Galerkin matrix is achieved by leading term extraction using asymptotic expansions for the Bessel´s and the Green´s functions and the summation of the leading terms is approximated with a super convergent series. This approach results in highly accurate results for the effective permittivity without the need for numerical integration or evaluating complex coefficients.