Improvement of Low-Frequency Magnetic Shielding Measurement Using Rhombic and Long Rectangular Loop Antennas

Abstract

For low-frequency magnetic field shielding measurement of large shielded rooms, the standard methods, such as IEEE-Std-299 and MIL-Std-188-125-1, are commonly used. In this letter, three types of loop antennas are analyzed to reduce the SE variation that occurs when using the standard measurement method based on the unit test area. Simulation shows that the rhombic and long rectangular loops can reduce the SE difference due to slot position compared to a conventional circular loop. Finally, a shielded room and loop antennas are fabricated and their effects verified through experiments.