Ultrawideband De-Embedding Calibration for Magnetic Field Probes by Using Symmetric GCPW Calibrators
Xinxin Tian, Shan Xue, Weiheng Shao, Duo‐Long Wu
Abstract
Microstrip line (MS) is commonly used as a calibrator for probe calibration. However, some issues need to be addressed for high-frequency applications, such as ripple and attenuation caused by the embedded part of the calibrator. In this article, an ultrawideband de-embedding calibration method (DCM) for magnetic field probes is proposed. Two symmetric nonsoldering grounded coplanar waveguide (GCPW) calibrators, including Through and Line standards, are used to solve the de-embedded <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$S$ </tex-math></inline-formula> -parameter matrix of a three-port calibration system. Compared with the traditional calibration method (TCM), the proposed method can reduce the influence of the reflection and attenuation caused by the embedded part and preserve the intrinsic properties of the probe itself. By using the DCM with a symmetric and good matched GCPW calibrator, the ripples of the DCM decrease by 6.57 dB, which is 82% of the TCM with an MS, and the attenuation has been compensated by about 0.7 dB at 10 GHz. In addition, a new characterization method of common mode electric field suppression ratio (CMSR) for <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$H$ </tex-math></inline-formula> -field probe is also presented, and it is applicable to conduct emissions measurement in which a probe can detect signals without 90° rotation.