| 摘要 |
PURPOSE:To make the reflecting characteristics of an electromagnetic wave reflecting body equal to that of ground, by determining the thickness of ferrite and the resistance value of film so as to make an impedance viewed from the resistance film to a ferrite plate almost equal to that of ground. CONSTITUTION:In an electromagnetic reflecting body 10, a ferrite plate 14 is bonded with a conductor plate 12, the surface of the plate 14 is coated with a resistance film 16 and a surface paint 18 is coated. The thickness of the plate 14 is determined so that the impedance viewing the ferrite plate of bonding construction with the plates 12 and 14 is almost equal to the impedance of ground of a test site. The film 16 adjusts the impedance of the plate 14. By providing the plate 16, the frequency characteristics of the ferrite can be suppressed and they are almost equal to those of ground. Especially, in the case of a floor for electromagnetic wave dark chamber for a car, the noise measurement of cars in a manufacturing plant and the noise-resistance measurement for electronic devices counted in the cars can be performed effectively. |
