In this chapter we study, in a rigorous manner, the bound modes of several transmission lines which find applications in both the microwave and millimetre wave frequency ranges, as well as in integrated optics. The bound modes of these transmission lines play a fundamental role in circuit design. As noted in previous chapters, in several instances it is possible to derive their properties by using suitable approximations, e.g. the effective dielectric constant method. However, when propagation constants must be known with greater accuracy, or when the approximations break down, or when the field shape is of interest as in discontinuity problems, it becomes necessary to employ rigorous procedures such as those described hereafter. Note also that, as new structures are considered, it is sometimes unclear what approximations are feasible; in these cases a prudent approach suggests using rigorous full-wave analyses.

Inspec keywords: electromagnetic wave propagation; integrated optics; electromagnetic wave diffraction; transmission lines

Other keywords: effective dielectric constant method; circuit design; transverse resonance diffraction; transmission lines; bound modes; propagation constants; full-wave analysis; integrated optics

Subjects: Transmission line theory