EMI Shielding Approaches for Wireless Designs

Abstract

Wireless transceivers and transmitters radiate intentional and unintentional electromagnetic (EM) signals. The unintended emissions result from electric (E) and magnetic (H) fields surrounding the current carrying traces, wire and other conductors. To address the concern for cellular phone electromagnetic interference (EMI) to aircraft radios, a radiated emission measurement process for wireless handsets has been proposed. Spurious radiated emissions can be efficiently characterized from devices tested in either a semi-anechoic or reverberation chamber, in terms of effective isotropic radiated power. This report provides a detailed description of a proposal of the measurement process.
Aircraft interference path loss (IPL) and navigation radio interference threshold data from numerous reference documents have been referred and proposed accordingly. Using this data, a preliminary risk assessment has been provided for wireless phone interference to aircraft localizer, Glideslope, VOR, and GPS radio receivers on typical transport airplanes. The report identifies where existing data for device emissions, IPL, and navigation radio interference thresholds needs to be extended for an accurate risk assessment for wireless transmitters in aircraft.
In order to suppress these types of effects several techniques have been proposed. We hereby propose a new technique for suppression of radiated EMI which is very essential in present day context in the field of wireless communication. In our article we have proposed for board-level shielding and EMI gasketing for wireless communication system designs.