Measurement of the complex dielectric constant of lossy fibers and rods at microwave frequencies.

Three related waveguide devices are described for measuring the dielectric constants of fibers and rods. In each device the sample is located one-quarter guide wavelength from the shorted end of the waveguide. A slot in the side or end of the guide permits easy insertion and removal of a fiber sample without having to thread it through holes in the waveguide. The dielectric constant along the length of the fibers can be measured as they are rapidly pulled through the device. The technique allows accurate measurement of samples having a wide range of diameters and dielectric constants. Measurements of carbon, nickel alloy, and alumina samples are described, and the experimental sources of error are analyzed. [ABSTRACT FROM AUTHOR]