Near‐field shielding measurement of small shield cans in metallic mobile devices for RF interference analysis

Abstract

A novel near-field shielding measurement method is presented for small shield cans used in modern mobile devices with metallic cases. To effectively capture electromagnetic leakage through the shield cans at the very near-field region, a stripline mounted on a test board is utilised similar to the integrated circuit stripline method. Using simulation and measurement, it is verified that the proposed method is more accurate and effective than the conventional gigahertz transverse electromagnetic (GTEM) cell measurement method for shielding evaluation of small shield cans used in metallic mobile devices from an radio-frequency interference point of view.

A review of measurement of electromagnetic emission in electronic product: Techniques and challenges

“…Studies and Applications [136] Far-field estimation from efficient Near-field measurement [138] Current scan technique for the radiated emissions prediction of automotive systems based CISPR 25 standard [139] Degrading radiated emissions using near-field scan method for Automotive EMC [140] Near-field emissions analysis based on EBG structures From CM Filters [142] Radiated immunity of PCBs using near-field scanning [150] RF interference analysis using near-field shielding measurement in metallic mobile devices [151] Application of RFI for inverse MoM for source reconstruction in near-field scanning technique [152] 3-D source reconstruction for near-field accuracy [153] Performances of near-field shielding of EMI noise suppression absorbers [154] Predicting far-fields from near-fields for EMC applications in broadband [155] Prediction the far-field using near-field scanning for microstrip line [156] Model of time-domain magnetic dipole of PCB Near-Field Emission [157] The minimum requirements model addressing the strength of electric and magnetic field strength measurement for use in near-field occupational exposure [158] Characterization of near-field for 13.56 MHz RFID [159] Near-field emission analysis from the PCB of a car deck player [160] The EM-Field probing Development for nearfield scanning [161] SNR Optimization for low near-field scanning [162] Quick antenna examining using lowered nearfield sampling [163] Characterization using near-field scanning [164] Near-field scan for investigating simultaneous switching noise OATS, Anechoic chamber, RC, and CATR have small experimental time, in contrast to NFS. While TEM has the medium experimental time.…”

An optimization method for conformal shielding

“…While an amount of the existing literature focused on the influence of shielding layer material and shielding layer thickness on SE [2,3,4,5,6,7,8,9,10,11,12]. There were also a number of studies on SE measurement methods in [13,14,15,16,17] and probe calibration in [18,19,20,21]. Moreover, some fast approaches were presented for the evaluation of near field SE in [22,23,24,25,26].…”