Characteristics of the Detection Voltages of an E-field Sensing Probe in SAR Measurement System

전자파 비흡수율(SAR) 측정용 전기장 프로브의 검파 전압 특성

  • Published : 2005.02.01

Abstract

The E-field intensity by mobile handsets in a phantom is measured by a 3 axes miniature probe. The detected DC voltage by a Schottky diode in a probe has nonlinear characteristics by itself. If a pertinent diode compression point (DCP) is applied for the compensation specific absorption rate(SAR) as much as 200 W/kg can be measured with a good measurement accuracy.

이동통신 기기로부터 복사되는 전자파가 인체에 흡수되는 에너지의 양은 모의 인체 내에서 전자파 비흡수율 [SAR(Specific Absorption Rate)]로 평가된다. RF 센싱 프로브의 Schottky 다이오드에 검출된 DC 전압은 높은 레벨에서 자승법칙(Square Law) 영역을 벗어나 선형성을 나타낸다. Square Law Region을 벗어난 직선 영역의 검파는 적절한 DCP(Diode Compression Point) 값으로 검 파된 전압을 보상하여야 한다. 적절한 보상에 의한 한 점에서의 SAR 값은 200 W/kg까지 측정할 수 있다.

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References

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