EMI Coupling Paths and Mitigation in a Board-to-Board Connector


Cage connectors for optical subassembly I/O modules have been identified as one of the main coupling paths in an optical link at the front-end of switches and routers. In the study presented herein, the simulation model used to study electromagnetic interference coupling physics and mitigation of the optical cage connector was corroborated by comparing the measured and simulated results for the total radiated power (TRP). Currents on the adjacent ground references to the differential signal conductors caused half-wave resonant peaks in the TRP response in the frequency range of 4-18 GHz. At frequencies from 18 to 28 GHz, both full-wave simulation and analytical formulas indicate that the radiation results primarily from the currents on the signal traces. The radiation from the optical cage connector was suppressed with absorbing materials, and the coupling path was verified, together with the optical cage and module enclosure.


Electrical and Computer Engineering

Research Center/Lab(s)

Center for High Performance Computing Research

Second Research Center/Lab

Electromagnetic Compatibility (EMC) Laboratory

Keywords and Phrases

Electromagnetic pulse; Electromagnetic wave interference; Interference suppression; Signal interference; Absorbing materials; Coupling paths; High frequency HF; mitigation; Optical cages; Radiation mechanism; Total radiated power; Optical switches

International Standard Serial Number (ISSN)


Document Type

Article - Journal

Document Version


File Type





© 2015 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Aug 2015