An approach to analysis of waveguide arrays with shaped dielectric inserts and protrusions

Abstract

The classical moment method solution of the waveguide-array problem is extended to allow for generally shaped dielectric matching inserts in the waveguide-to-free-space transition region. The aperture electric field is represented in terms of waveguide modes. To account for the presence of the matching inserts, the aperture fields are numerically propagated through the dielectric regions. Novel matching configurations, which extend the scanning range of waveguide elements or can be used to shape the element pattern in limited-scan applications, are proposed and analyzed.

Analysis of Doubly Periodic Inhomogeneous Dielectric Structures by a Hybrid Projective Method

“…Note that relation (26) first provides the necessary condition for the magnetic field with components (7) and (9) and second reduces the number of the unknown coefficients standing in expressions (6) and (7) compared to the incomplete Galerkin method [20], [34] and the method of couple waves [2], [22]- [24].…”

“…A list of such methods includes: -the method of surface integral equations [10], [11] -the method of auxiliary sources [12]; this method for twodimensional problems is easier than the method of surface integral equations, but it can be applied to the scatterers with smooth surfaces; -the method of integral equations for polarization currents [13], [14]; it is more universal than the previous two methods, since it allows analysis of inhomogeneous dielectric scatterers; -the finite-difference frequency-domain (FDFD) method [15], also allowing analysis of inhomogeneous scatterers; -the method of pattern equations [16], applicable only to homogeneous scatterers; its effectiveness is questionable, since [16] contains neither numerical results for comparisons with other methods; -the finite element method (FEM) [17] and its hybrid versions, for example [18], which are also universal; -the boundary element method [19]; and -a group of universal methods reducing the problem to systems of ordinary differential equations, including incomplete Galerkin method [20], unimoment method [21], method of coupled waves [22]- [24], used in [2], a modification of the coupled mode method combined with one-dimensional finite element method [25] and method of cross sections used in [26]. A hybrid projective method, relative to [25], was recently developed in [27] and [28] for analysis of one-dimensional periodic structures with wedge elements for application to matching layers and absorbing covers.…”