Analysis of Site Attenuation for an Anechoic Chamber using an Imaging Method

Abstract

Anechoic chamber characteristic is evaluated by SA (Site Attenuation). To optimize an anechoic chamber (its size and absorber), it is necessary to forecast the SA by calculation before constructing anechoic chamber. As for Open test site, the technique which solve impedance matrix of image antenna to calculate the SA has already been shown. However, in order to extend this technique for the anechoic chamber, an efficient algorithm of the mirror image is necessary. In this paper, we showed the algorithm of an imaging method (Ray trace method) that is able to be applied to the anechoic chamber with an arbitrary polygon shape. As a result, it was confirmed that the calculation value by this algorithm and actual measurement value was corresponding well.