If it is possible to derive the complex permittivity of a dielectric materi
al by measurement of the coefficient of reflection from the aperture of a f
langed rectangular waveguide attached to a conductor-backed lossy dielectri
c sheet, an effective nondestructive measurement method can be established.
in this paper, by solving simultaneous equations derived by an application
of the spectral. domain method, contour maps for derivation of the complex
permittivity of a lossy dielectric from the reflection coefficient are for
med and their characteristics are studied. The effectiveness of these conto
ur maps is confirmed by experiments. In the region within the contour chart
where the permittivity can be determined with good accuracy, it can be det
ermined with an error of about 5% by means of a general-purpose network ana
lyzer. Further, the attenuation of the electromagnetic wave within the loss
y dielectric in the direction of propagation is studied in order to derive
the dimensions of the sample and flange needed for actual measurement. (C)
2001 Scripta Technica, Electron Comm Jpn Pt 2, 84(4): 59-67, 2001.