| 摘要 |
PURPOSE:To reduce the effect of a power feeding part on a measuring result, by vertically installing a pair of antennae on the surface of an earthed metal plate at a predetermined interval and generating imaging effect on the rear surface side of the metal plate. CONSTITUTION:A pair of semi-loop antennae 8a, 8b are vertically installed on the surface of an earthed metal plate 2 at a predetermined interval. A power is fed to the feeding point of the antenna 8a from the back surface side of the metal plate 2 through a connector 10a so that imaging effect is generated on the back surface side of the metal plate 2 and the receiving output from the receiving point of the antenna 8b is taken out from the back surface side through a connector 10b. Then, shield effect is evaluated on the basis of the ratio of the receiving output in such a state that a test sample is not arranged and the space between the antennae 8a, 8b continues and the receiving output in such a state that the test sample 1 composed of a cup-shaped half-split body made of a conductive material is arranged and the space between the antennae 8a, 8b is blocked by the test sample 1. Further, a monopole antenna is used in the measurement of magnetic field shielding effect.
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