Analysis of semi-anechoic chamber using ray-tracing technique

Abstract

A semi-anechoic chamber is known to be useful for EMC measurements in a frequency range from 30 MHz to 1000 MHz. The analysis using a ray-tracing technique is investigated to evaluate a normalized site attenuation in the semi-anechoic chamber which is used for EMC measurements in a 3 m or 10 m method. The validity of the analysis is verified for a chamber lined with a multi-layer ferrite absorber by comparison with experimental data. The analysis is also applied to estimate the thickness of pyramidal absorber required to satisfy the ANSI standard.