An Efficient Evaluation of the Self-Contribution Integrals in the Spectral-Domain Analysis of Multilayered Striplines

A very accurate technique to analyze the propagation in multilayered striplines is the Galerkin´s method in the spectral domain with Chebyshev polynomials basis functions weighted with the edge behavior of the unknown surface current density on the metallic strips. Unfortunately, such a method leads to the numerical evaluation of improper integrals of oscillating and slowly decaying functions. Recently, a new technique specifically devised to efficiently evaluate the mutual coupling integrals has been proposed by the author. In this letter, such a technique is extended to efficiently evaluate the integrals of self-contribution.