Analysis of Coupling Efficiency for the Double Layer Shielding Cavity with Aperture

TLM (transmission line model) is used to research the coupling characteristic of electromagnetic pulse and it is extended to calculate the coupling efficiency of double layer shielding cavity through apertures. The effect of single layer with aperture is compared with double layer with apertures on the coupling efficiency of electric field; the calculation results show that shielding efficiency can be improved greatly with double layer shielding. At the same time, the model is extended to include higher-order transverse electric (TE) and transverse magnetic (TM) cavity modes in the transmission line model and remains very simple and computationally efficient. The finite-difference time-domain (FDTD) result is used to compare the results.