More on field perturbations due to accessories used in radiated emissions tests

Normalized site attenuation (NSA) measurements are taken in the absence of necessary accessories, such as the 80 cm-high table on which test samples must be supported We presented a paper at the 2001 IEEE EMC Symposium, documenting measurement anomalies that come from field distortions caused by test accessories. This paper reports on additional work in this area. The paper updates our proposed technique for assessing the far-field signal perturbations that result from inserting test accessories into the common environments encountered in measuring ITE products.