For a small-sized shielding enclosure, an infinitesimal monopole antenna is installed inside an enclosure to measure the quality factor and the shielding effectiveness. The characteristic of the monopole antenna, however, affects the measurement of the quality factor and the shielding effectiveness. This article proposes a new measurement method that does not require any antenna installation inside the enclosure. Instead, the proposed method utilizes an aperture on the enclosure surface. A theoretical model is derived for the enclosure response, which represents a response of the enclosure when a pulse signal is incident to the enclosure in the nested reverberation chamber. The response model is used to measure the quality factor and the shielding effectiveness, respectively. The enclosure response affected by an aperture on the enclosure surface is measured, and the measured response is then used to calculate the quality factor by comparing it with the response model. The response model also is used to measure the shielding effectiveness. The enclosure responses are measured with two aperture conditions, respectively, and the shielding effectiveness is calculated using the measured responses. The proposed method is advantageous in that the quality factor and the shielding effectiveness of a small-size enclosure can be accurately measured without being affected by the quality factor of the monopole antenna.

中文翻译：

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嵌套混响室中无天线外壳的品质因数和屏蔽效能测量

对于小型屏蔽外壳，在外壳内部安装一个无穷小的单极天线来测量品质因数和屏蔽效果。然而，单极天线的特性会​​影响品质因数和屏蔽效果的测量。本文提出了一种新的测量方法，不需要在外壳内安装任何天线。相反，所提出的方法利用外壳表面上的孔。推导出外壳响应的理论模型，该模型表示当脉冲信号入射到嵌套混响室中的外壳时外壳的响应。响应模型分别用于测量品质因数和屏蔽效能。测量受外壳表面孔径影响的外壳响应，然后使用测量的响应与响应模型进行比较来计算品质因数。响应模型也用于测量屏蔽效果。外壳响应分别在两种孔径条件下测量，屏蔽效率使用测量的响应计算。所提出的方法的优点在于可以准确地测量小尺寸外壳的品质因数和屏蔽效率而不受单极天线品质因数的影响。外壳响应分别在两种孔径条件下测量，屏蔽效率使用测量的响应计算。所提出的方法的优点在于可以准确地测量小尺寸外壳的品质因数和屏蔽效能而不受单极天线品质因数的影响。外壳响应分别在两种孔径条件下测量，屏蔽效率使用测量的响应计算。所提出的方法的优点在于可以准确地测量小尺寸外壳的品质因数和屏蔽效能而不受单极天线品质因数的影响。