Accession Number : ADP007734

Title :   A High Temperature Microwave Dielectrometer,

Corporate Author : ALBERTA UNIV EDMONTON DEPT OF ELECTRICAL ENGINEERING

Personal Author(s) : Xi, Weiguo ; Tinga, W. R.

Report Date : 27 APR 1992

Pagination or Media Count : 10

Abstract : A microwave dielectrometer has been developed f or measuring dielectric properties of various oxides and ceramics at up to at least 1200 0 C. This system uses a re-entrant coaxial cavity with a hollow center conductor both as a microwave heater and as a test chamber. A small cylindrical sample is easily introduced into the cavity through an insertion hole and tested in the frequency band of 3GHz while being heated by a tunable 6OW solid state source of 915MHz. The sample temperature is measured with an optical fiber thermometer. The speed, convenience and accuracy of this system may make instant on-line measurements possible. In this paper, the sample loading effect and the hole effect on the characteristics of the cavity are discussed based on the results from our mode-matching analysis. The theoretically predicted calibration curves for determining dielectric constants and loss tangents are provided in polynomial form. Error estimations are also included. The system setup is described and part of our experimental results are presented to demonstrate the system performance.

Descriptors :   *DIELECTRIC PROPERTIES, *MICROWAVES, *CERAMIC MATERIALS, ACCURACY, CALIBRATION, CAVITIES, CHAMBERS, CONSTANTS, DIELECTRICS, ERRORS, FIBERS, FREQUENCY, FREQUENCY BANDS, HEATERS, MATCHING, MEASUREMENT, OXIDES, PAPER, POLYNOMIALS, SOLIDS, TANGENTS, TEMPERATURE, TEST AND EVALUATION, THERMOMETERS, VELOCITY, RESONANT FREQUENCY.

Subject Categories : Ceramics, Refractories and Glass
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE