Retrieving the reflection coefficient of a sample from the frequency response of a special open resonator

This paper focuses on accurate measuring the electromagnetic reflection at K band from flat samples made of a composite material or a metal mesh. A special open resonator comprising a sample under test features a good sensitivity due to multiple reflections in the cavity and absence of any contact between the sample and the installation. Data processing algorithm arises from geometric optics description of the microwave field in the resonator. Digital modeling with the CST Microwave Studio software and real experiments with use of ZVA50 signal analyzer confirmed efficiency of the proposed technique.