Accuracy improvement in permittivity measurement of construction materials by use of a model of the standing wave method in free space

摘要

A model of the measuring system has been developed to estimate accurately the complex permittivity of construction materials based on the standing wave method in free space. It is assumed in the model that the standing wave distribution is represented by the sum of the incident-, reflected- and scattered-wave components. In this paper, the measurement conditions of the model based measuring method have been discussed by means of computer simulation using FDTD techniques. It has been concluded that the size of the materials should be larger than 600 millimeters square in order to estimate complex permittivity accurately by the model based method.