Development of artifact for inter-laboratory comparison for the purpose of improving reproducibility of radiated emission test

Abstract

AC power driven electronic products such as PCs, printers, copiers also radiate electromagnetic disturbances from their AC power cable not only from their chassis. The strength of the radiated emission from the AC power cable is affected by the impedance-about-ground of the EUT power feeding port of the radiated emission testing laboratory. However, the radiated emission from the AC power cable varies depending on the testing laboratories by the impedance-about-ground of EUT power feeding port, and the impedance-about-ground is not specified in the standards. To evaluate the effects of the impedance-about-ground of the EUT power feeding port of radiated emission testing laboratories by means of inter-laboratory comparison program (proficiency test), it cannot be evaluated precisely by using artifact that do not have AC power cable. Moreover, the influences of the impedance-about-ground cannot be solved by means of the site attenuation or other propagation analysis. We developed artifact that driven by AC power (having AC power cable) and the artifact was used for inter-laboratory comparison program organized by VLAC in past 10 years. The artifact brought significant merit for the practical inter-laboratory comparison for the purpose of improvement of reproducibility of radiated emission test.