For studying the coupling effect of electromagnetic irradiation to rectangular enclosure with wire penetration

a new hybrid model is proposed to determine the shielding effectiveness of the enclosure.This model based on rectangular-enclosure equivalent circuit regards the penetrating wire as a monopole antenna

and the frequency-domain results of calculation using this model match with that of computer simulation technology（CST）Microwave Studio.Meanwhile

this new model requires far less computation than traditional methods:3 s for one sample on an average personal computer.Based on the presented model

the relationships between enclosure volume

external length of wire penetration

internal length of wire penetration

and shielding effectiveness are analyzed.In the frequency range from 100 MHz to1 000 MHz

when keeping the length of penetrating wire unchanged

the shielding effectiveness of an enclosure at its center point increases with the cavity volume.There is no obvious effect from the external length of penetrating wire on the shielding effectiveness.If the external length of a penetrating wire is 8 cm unchanged

the shielding effectiveness of the penetrated enclosure at its center point declines with the increase of internal length of the penetrating wire.