Estimating the Radiated Emissions from Cables Attached to a Switching Power Supply in a MIL-STD 461 Test


Common-mode currents on cables attached to a switching power supply generate radiated emissions which may interfere with near-by components. A relatively simple equivalent circuit model is developed to predict the radiated emissions measured in a MIL-STD-461 or RTCA/DO-160 test. The intent of this model is to provide an estimate of emissions that allows the designer to better understand the mechanisms behind emissions issues and to rapidly predict the impact of changes to the system, like adding filtering, changing components, or modifying cable connections. The model represents cables connected to the power supply as transmission lines, represents coupling from the cables to the antenna using lumped capacitors, and represents the balun in the antenna using a transformer. The simulated results match the measured results well. This simple SPICE model allows EMI issues to be investigated early in the design of switched mode power supplies.

Meeting Name

2013 IEEE International Symposium on Electromagnetic Compatibility (2013: Aug. 5-9, Denver, CO)


Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory

Keywords and Phrases

Biconical Antenna; EMI Modelling; MIL-STD 461D; Radiated Emissions; Switched Mode Power Supplies

International Standard Book Number (ISBN)


International Standard Serial Number (ISSN)


Document Type

Article - Conference proceedings

Document Version


File Type





© 2013 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Aug 2013