Field Coupling Mechanism Investigation of mm-Wave Magnetic Near-Field Probe based on a Generalized Equivalent Circuit


A field-response-equivalent circuit is advantageous for explaining the field coupling mechanism of H-field probes. Previous works have primarily explained the coupling between a field probe and the calibration kit. In this paper, a field coupling circuit model is proposed in a generalized form to directly predict the voltage induced by the H-field and the unwanted E-field in the probe for the mm-wave range. The field response circuit model is based on the loop impedance model and incident field response of a loop antenna in the form of a series expansion. This paper reveals that the zero-mode response corresponds to H-field coupling, whereas the first mode corresponds to E-field coupling and is validated through the numerical simulation based on the circular loop antenna. The coupling of the fabricated H-field probe is predicted based on the equivalent circuit model and the prediction matches numerical simulation and measurement results from 1 GHz to 40 GHz. The equivalent circuit can be used to predict the probe field coupling with an error of less than 4 dB. Finally, this paper provides a generalized equivalent circuit as a tool to analyze and understand the probe field coupling quantitively. This paper reuses some content from thesis in sections I, II and III with permission.


Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory


This paper is based upon work supported in part by the National Science Foundation under Grant No. IIP-1916535.

Keywords and Phrases

Antennas; Couplings; Equivalent Circuit; Equivalent Circuits; Field Coupling Mechanism; H-Probe; Integrated Circuit Modeling; Load Modeling; Magnetic Near-Field Probe; Probes; Voltage

International Standard Serial Number (ISSN)

1557-9662; 0018-9456

Document Type

Article - Journal

Document Version


File Type





© 2022 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

17 Feb 2022