Improvement of shielding measurement for small‐sized enclosures with consideration to the shielding quality of antenna cables

Abstract

AbstractThis article presents an improvement to IEEE 299.1 standard used to measure the shielding effectiveness (SE) of small‐sized metallic enclosures in a reverberation chamber. The shielding quality of radio‐frequency (RF) cables used for SE measurement significantly affects measurement accuracy, especially when metallic enclosures have a high level of SE. A new measurement parameter is introduced to represent a measurable range in which SE can be measured without being affected by the shielding quality of the RF cables. The proposed parameter can be effectively used for the IEEE 299.1‐based SE measurement method to improve measurement accuracy. In our experiments, the utilization of the proposed parameter confirms that the IEEE 299.1 method can measure SE of 87.5 dB up to 4 GHz. Furthermore, to reduce coupled noise through the antenna cable, three different methods are applied together during the shielding measurement of a high‐SE enclosure. Our experimental results show that these methods extend the measurable SE range up to 95 dB at frequencies below 4 GHz.