Browsing by Author "Wakino, Kikuo"

Now showing 1 - 3 of 3

Evaluation of Complex Permittivity of Materials with Deformed Cross-section in Coaxial Line
(2009)
Sakemoto, Yuya
;
Harada, Atsushi
;
Wakino, Kikuo
;
Lin, Yu-De
;
Kitazawa, Toshihide
A broadband measurement method is presented to evaluate the complex permittivity of a deformed sample. Theoretical basis of the method is the hybrid electromagnetic field analysis, i.e, the extended spectral domain approach combined with mode-matching method (ESDMM). The sample is required to have the rotational symmetry but may have the deformation and/or air gap between the sample and the conductor walls of coaxial line, which eases the machining accuracy of sample. The proposed evaluation method is verified by virtual experiments as well as actual measurements.
Simultaneous Determination of Complex Permittivity and Permeability of Columnar Materials With Arbitrarily Shaped Cross Section
(2009-09-01)
Miyagawa, Hayato
;
Wakino, Kikuo
;
Lin, Yu-De
;
Kitazawa, Toshihide
;
電信工程研究所
An effective simultaneous evaluation method for the complex permittivity and permeability of lossy materials is proposed by applying it to an arbitrarily shaped cross-sectional post placed in a rectangular waveguide. We use one sample and only measure S(21) parameters for two different locations of the sample. The measurement of complex reflection parameter S(11) is not required in this evaluation method. The scheme of electromagnetic field analysis for the evaluation is based on the extended spectral-domain approach combined with the mode-matching method, which is accurate and efficient, and can be flexibly used for the iterative fitting operation for the estimation of material parameters. Sample preparation and setting is significantly easier in this method compared to conventional methods. The error caused by deviations in the setting of a sample is investigated. The estimated values for the sample material by this procedure show good agreement with the results obtained using the conventional method over the X-band.
Spectral domain approach to the scattering analysis of coaxial discontinuities
(2007-02-01)
Nakata, Takamichi
;
Yoshitake, Hiroaki
;
Wakino, Kikuo
;
Lin, Yu-De
;
Tani, Tohru
The extended version of spectral domain approach (ESDA) is applied to evaluate the scattering characteristics of discontinuities in coaxial line. Discontinuities may be in inner and/or outer conductor of coaxial line. This method secures the high accuracy by considering the singularities of fields near the conductor edge properly. The computational labor of the new method is far lighter than that of FEM, so that novel method is suitable for the time consuming iterative computation such as fitting procedure in material evaluation or optimization of antenna design.