Measurement and Analysis of Passive Intermodulation Induced by Additional Impedance in Loose Contact Coaxial Connector


The mechanism of the passive intermodulation (PIM) distortion caused by the loose contact in coaxial connectors is of great importance in wireless communication systems. This paper focuses on the effect of the additional impedance on PIM levels in coaxial connectors. First, the additional impedance and PIM levels of the loose contact coaxial connectors are measured. Then, the S-parameters and the additional impedance with three different loose contact cases are simulated. Finally, a modified coaxial connector with different values of conductive tapes is designed to verify the additional impedance impacts on the PIM level. It is shown that the increase of the additional impedance of the metal-metal loose contact will lead to the deterioration of PIM levels in the coaxial connector.


Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory


This work was supported in part by the National Natural Science Foundation of China under Grant 61771190, in part by the Natural Science Foundation of Hunan Province under Grant 2019JJ2001, in part by the Science and Technology Major Project of Hunan Province under Grant 2017GK1051, and in part by the Education Department of Hunan Province with Contact no. CX2016B130.

Keywords and Phrases

Additional Impedance; Coaxial Connector; Loose Contact; Passive Intermodulation (PIM)

International Standard Serial Number (ISSN)


Document Type

Article - Journal

Document Version


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© 2019 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Dec 2019