Measurement Method for Shielding Effectiveness of Metal Mesh Specimen in Free Space S-Band

In this study, we propose a method to measure the shielding effectiveness of relatively small mesh specimens, which are smaller than those typically used in free-space measurements, in S-band free space, where diffraction effects are significant, without using a lens horn antenna. The proposed method involves placing an absorber panel between the transmitting and receiving antennas and applying a time-gating technique to the measured scattering parameters to determine the shielding effectiveness. First, the shielding effectiveness was calculated by modeling the metal mesh specimen at the wire grid level, which was verified using FEKO simulation. We then conducted shielding effectiveness measurements of metal mesh specimens A and B in an actual S-band free space. Subsequently, the measured results are compared and validated against the results derived from the formulas and simulations. The differences among the measured, formula-derived, and simulation results were all within 3 dB, confirming the validity of the proposed measurement method.