Determination of Shielding Effectiveness of Multilayer Shield by Making Use of Transmission Line Theory

Arbitrary multilayer plate shielding is investigated by equivalent nonuniform transmission line method. A general formula which can be applied to analyze arbitrary multiplayer plate shielding is proposed. This new method utilizes network parameter matrix of nonuniform transmission line to analyze plate shielding effectiveness for the first time. Owing to the discontinuity of nonuniform transmission line, it is fit to model multilayer plates regardless of the reflection between plates. It makes analysis concise and convenient to take material characteristic into account. In addition, matrix presentation is suit for program and can get result in a few seconds. Special cases of double and fourfold shield are calculated. The accuracy of this method has been validated by comparison to other analytical methods.