In this study, a wideband rounded-shield calibration fixture or jig used to calibrate in-band injection probe is implemented based on 3D electromagnetic modelling in CST Microwave Studio; the Electromagnetic (EM) model is validated and then used in studying the effect of the jig layout parameters on its bandwidth. The impact of a rounded instead of the typical flat shield is studied too, and showed an improvement of about 15% in the bandwidth at Voltage Standing Wave Ratio (VSWR) level of 3. A new systematic rules procedure for extracting the circuit model of transmission lines based structures is proposed and applied in deriving a circuital model for the jig. The EM and developed circuital models are validated versus vectorial scattering parameters and VSWR. The estimation of the uncertainty shows small values at the band of measurement. The developed prototype meets DO-160 and MIL-STD-461E requirements and shows an improved high frequency performance when compared with reliable products. An application is presented in measuring the insertion loss of bulk current injection probe and in illustrating the effect of the shield slot distance on the probe High Frequency (HF) performance.

中文翻译：

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体电流注入探头校准夹具的改进设计的电磁和电路建模

在这项研究中，基于CST Microwave Studio中的3D电磁建模，实现了用于校准带内注入探头的宽带圆形屏蔽校准夹具或夹具。验证电磁（EM）模型，然后将其用于研究夹具布局参数对其带宽的影响。还研究了倒圆角而不是典型的平面屏蔽的影响，在电压驻波比（VSWR）为3的情况下，带宽提高了约15％。一种新的系统规则程序用于提取传输电路模型提出了基于线的结构，并将其应用于夹具的电路模型。EM和已开发的电路模型已针对矢量散射参数和VSWR进行了验证。不确定性的估计在测量范围内显示出较小的值。开发的原型满足DO-160和MIL-STD-461E的要求，并且与可靠的产品相比，具有更高的高频性能。提出了一种在测量大电流注入探头的插入损耗以及说明屏蔽槽距对探头高频（HF）性能的影响方面的应用。