Indirect Measurement of Shielding Effectiveness of an Enclosure for a Security Camera

This paper presents the results of our experiment, which consisted in measurement of the shielding effectiveness of a camera enclosure that was designed and constructed in order to increase the susceptibility of a camera against external electromagnetic fields. All activities, from defining of requirements to final design and measurements, were performed in the Laboratory of Electromagnetic Compatibility at the Faculty of Applied Informatics of Tomas Bata University in Zlín. The hereby described approach allowed to utilize standardized laboratory equipment that is normally used for device susceptibility test to radiated electric field. The measurement was made inside a semi-anechoic room additionally damped by absorbers placed on its floor. When configuring the experiment, relevant EMC standards EN 55016 and EN 61000-4-3 were considered. Although the uncertainty tolerances, allowed by the relevant standards, were quite high for measurements in such rooms, the results obtained by the experiment matched the theoretical expectations quite satisfactorily.