Some results of the numerical analysis of slot and microstrip-slot lines

A numerical analysis is presented of the fundamental and higher natural modes of slot and microstrip-slot transmission lines. The investigation is based on the algorithms of Fedorov et al. (1979, 1981), which employ Chebyshev polynomials in the expansion of natural modes of waveguide elements; five basis functions were used in the expansion on the natural-mode distributions, which assured a calculation error of less than tenths of a percent. The dispersion characteristics and natural-mode field distributions on waveguide lines are presented, and an analysis is made of the mutual influence of microstrip and slot lines on wave propagation in composite systems.