Inter-laboratory comparison between CISPR25 chambers, identification of influent parameters and analysis by 3D simulation

In automotive industry, the reference standard used to perform radiated emissions measurements is the CISPR25 [1]. Previous works [2-5] already pointed out that between different labs supposed to be CISPR25 compliant, test results obtained on simple equipment could differ quite significantly (more than 10 dB reported). We identified in [2,3] some parameters at the origin of these deviations, linked to the degrees of freedom in the chamber setup definition in CISPR25. A simultaneous analysis based on the inter-laboratory measurements results linked to the chambers definitions and analysis performed with 3D simulation allowed to establish what are the main influent parameters and their significance. This paper exposes the measurements results and analysis over 13 labs as well as the correlation with 3D simulation to justify about the influence of these parameters individually considered.