Chamber Influence Estimation for Radiated Emission Testing in the Frequency Range of 1 GHz to 18 GHz

he paper presents a comprehensive analysis of the behavior of anechoic chambers in the frequency range from 1 GHz to 18 GHz. Numerical simulation and statistical analysis have been used to estimate the influence of the test site to radiated emission results above 1 GHz. For typical EMC chambers the influence factor is around 0.7 dB. This factor can be improved by using better absorbing material or increasing of chamber size. For a wide range of EUT´s the compliance uncertainty can be estimated using the chamber influence factor. The prediction of the chamber influence for small omnidirectional EUT´s fits very well. Small EUT´s with a directive disturbance source are overestimated. Large EUT´s with multiple sources have not been investigated.