Toshihide Kitazawa

Propagation characteristics of coplanar-type transmission lines with lossy media

Lossy coplanar-type transmission lines are analyzed based on the hybrid-mode formulation by combining the spectral-domain approach with the perturbation method. Introducing a finite thickness of metallization and choosing the proper basis functions for the thick conductor model prevent the integrals used for calculating the conductor losses from becoming singular when evaluated at the conductor edge. An orthogonality relation is used to reduce the double infinite or semi-infinite integral to a single integral, thus reducing the computation effort drastically. Numerical computations by new basis functions for the thick conductor show convergence rates as fast as those for the zero-thickness cases. Numerical results include the effective dielectric constants, characteristic impedances, and total losses (conductor and dielectric losses) for slot lines and symmetrical and asymmetrical coplanar waveguides. >

Quasi-Static Characteristics of Asymmetrical and Coupled Coplanar-Type Transmission Lines

In this paper, variational expressions for the capacitances of asymmetrical and coupled coplanar-type transmission lines are derived. The methods employed are quite general, and are useful for analyzing various types of coplanar-type transmission lines, with either an isotropic or anisotropic substrate. An accurate and efficient method of calculation is provided for the variational expressions, and some numerical results are presented.

Analysis of shielded striplines and finlines with finite metallization thickness containing magnetized ferrites

The applicability of the spectral domain approach is extended to analyze various types of shielded planar transmission lines, taking the anisotropy of the magnetized ferrites and the finite metallization thickness into consideration. The numerical computations include the propagation characteristics of finlines and striplines and the metallization thickness effect in these lines. Numerical data of simpler structures are compared with the available exact solution as well as with published data. >

Metallization thickness effect of striplines with anisotropic media: quasi-static and hybrid-mode analysis

The effect of metallization thickness in striplines is investigated on the basis of the quasi-static and frequency-dependent hybrid-mode formulations. The formalism utilizes the aperture fields as source quantities and uses the extended version of the network analytical methods of electromagnetic fields. It is therefore applicable for the general structure, i.e., coupled thick strips with uniaxially anisotropic media. Numerical computations include comparisons with available data for the simpler cases to show the accuracy of the present method and the quasi-static and frequency-dependent hybrid-mode solution for single and coupled thick strips with anisotropic media. >

Analysis of Asymmetric Coupled Striplines (Short Papers)

A unified method for the quasi-static and the hybrid-mode formulation of asymmetric coupled striplines is presented. Variational expressions are derived for the matrix elements, which describe the quasistatic characteristics, for the first time. A very accurate numerical method is shown and some numerical examples are presented for the different types of asymmetric coupled striplines with anisotropic substrates.

An Investigation of Striplines and Fin Lines with Periodic Stubs

In this paper, a technique based on the network-analytical formalism of electromagnetic fields is used to analyze the strip and fin lines with periodic stubs. Numercal results for the dispersion characteristics of the periodically loaded lines are presented. The effect of the loading stubs on the passband and stopband characteristics is investigated.

Variational method for multiconductor coupled striplines with stratified anisotropic media

Numerical examples are presented for the propagation constants as well as the characteristic impedances of various types of multicoupled striplines. Numerical computations are performed very accurately to provide sufficient precision even for tight coupling between strips of the multiconductor system. The basis functions used in the calculation are increased up to ten. Accurate numerical results reveal the mode coupling in the multimode propagation. >

Variational method for planar transmission lines with anisotropic magnetic media

Upper and lower bounds on the line inductances are presented for the first time for planar transmission lines with anisotropic magnetic media. Greens functions are derived for the general structure by using recurrent relations. Numerical examples involving striplines and coplanar waveguide are presented, and the calculated values of the quasi-static characteristics of stripline on an anisotropic magnetic substrate with the tensor permeability are in good agreement with measured values. >