Worst Case Prediction of Shielding Effectiveness of Board Level Shields

Abstract

A method is proposed to predict the worst case shielding effectiveness of a board level shield (BLS). This method estimates the shielding effectiveness (SE) of the shield below and above the first resonance of a cavity formed by the BLS. The apertures of the BLS are modelled as antennas with known radiation efficiency. The estimation of the maximum field inside the cavity is used to calculate the magnetic currents driving the antennas above the first resonance of the cavity. Below the first resonance the field inside the cavity is estimated using the resonant LC circuit model. An approximated formula for the radiation of the uniformly placed apertures is developed. The worst case prediction is validated by the full wave simulation and also in measurement on a real BLS.

Meeting Name

2017 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity, EMCSI (2017: Aug. 7-11, Washington, DC)

Department(s)

Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory

Keywords and Phrases

Aperture; Board Level Shield; Cavity; EMI; Shielding Effectiveness; Total Radiated Power

International Standard Book Number (ISBN)

978-1-5386-2229-2

International Standard Serial Number (ISSN)

2158-1118

Document Type

Article - Conference proceedings

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2017 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Aug 2017

Link to Full Text

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