An Automated Dual Horn-Reflector Microwave Absorber Measurement System. Volume I

摘要

In recent years, extreme interest has been shown in materials which absorb electromagnetic energy in the microwave and millimeter frequency bands. One of the primary methods of evaluating Radar Absorbing Materials (RAM) is to obtain the electrical and magnetic constants of permittivity (epsilon) and permeability (mu) of the material from which the RAM is constructed. Usually, the (mu, epsilon) of a typical microwave absorber varies strongly as a function of frequency. Hence, in order to evaluate the performance of a wide band microwave absorber, it would de desirable to design and build a system which measures (mu, espilon) across a wide frequency band. The Dual Horn-Reflector Microwave Absorber Measurement System discussed herein obtains the (mu, epsilon) of a homogeneous rectangular sample of material from 12.6 - 18.0 Gigahertz by measuring the scattering parameters S11(omega) and S21(omega) from the sample directly in the Frequency Domain. The overall accuracy of this measurement system is five to ten percent.