Accession Number:

AD0657055

Title:

A STANDING-WAVE METHOD FOR THE MICROWAVE EVALUATION OF DIELECTRIC AND MAGNETIC MATERIALS

Descriptive Note:

Progress rept. 15 Sep 1965-15 Jun 1966

Corporate Author:

MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB

Personal Author(s):

Report Date:

1966-07-15

Pagination or Media Count:

32.0

Abstract:

The report presents results of an investigation into the standing- wave method for evaluation of microwave loss and effective dielectric constant of low-loss ceramic materials. The objective of the study was primarily to devise a sensitive method for determination of the dependence of loss on the magnetic state of ferrites and ferrimagnetic garnets in various conditions of remanence. Design of a special coaxial slotted line and specimen holder is described. Preparation of specimens, including metallization of surfaces, is discussed. Data taken at S-band approx. 3 GHz on a dielectric and garnet material are presented. They show that the sensitivity of the method in its present form is marginal for the purpose, although within an order of magnitude of that of conventional resonant-cavity methods. A means for accurately determining a correction for distributed loss in the slotted line is presented. The report includes graphs of the theoretical voltage ratio 1VSWR versus electrical length of the specimen, for low-loss material having dielectric constants in the range 8 -- 16, together with the computer program used to calculate these graphs.

Subject Categories:

  • Ceramics, Refractories and Glass
  • Miscellaneous Materials
  • Test Facilities, Equipment and Methods

Distribution Statement:

APPROVED FOR PUBLIC RELEASE