A simple microwave interferometer for measuring effective thickness of dielectric slabs

Author

Ashkenazy, Y. ; Levine, Esther ; Treves, David

Author_Institution

Dept. of Electronics, Weizmann Inst. of Sci., Rehovot, Israel

Issue

4

fYear

1981

Firstpage

243

Lastpage

247

Abstract

A Michelson-type unequal path interferometer for measuring the effective thickness of dielectric slabs is presented. Due to unequal paths, this interferometer is frequency dependent so that frequency tuning of the source controls the phase difference between the two paths and serves as a phase shifter. FM modulation of the source enables determination of the null point with an electronic sensitivity of 0.02°. High spatial resolution (≃λ/2) is achieved by spacing a suitable horn antenna close to the dielectric surface. Detailed design considerations and experimental results concerning an X-band interferometer are presented.

Keywords

dielectric measurement; electromagnetic wave interferometers; microwave measurement; Michelson-type unequal path interferometer; X-band interferometer; bidirectional coupler; effective thickness of dielectric slab measurement; horn antenna; microwave interferometer; null point; phase shifter; Antenna measurements; Dielectrics; Frequency modulation; Microwave filters; Microwave measurements; Sensitivity; Transmission line measurements;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/TIM.1981.6312399

Filename

6312399