전도성 금속 피복재의 전기전도도에 의한 전자파 차폐효과 분석

김영식; 최익권; 김성수; Young-Sik Kim; Ik-Gueon Choi; Sung-Soo Kim

Korean Journal of Materials Research, Vol.9, No.9, 913-918, September, 1999

Export Citation

전도성 금속 피복재의 전기전도도에 의한 전자파 차폐효과 분석

Analysis of Electromagnetic Wave Shielding Effectiveness from Electrical Conductivity of Metallized Conductive Sheets

김영식, 최익권¹, 김성수

충북대학교 재료공학과
¹충북대학교 전파공학과

Young-Sik Kim, Ik-Gueon Choi¹, and Sung-Soo Kim

Department of Materials Engineering, Chungbuk National University, Cheongju 361-763, Korea
¹Department of Radio Engineering, Chungbuk National University, Cheongju 361-763, Korea

초록

전자파 차폐특성 측정방법의 일환으로 매질의 전기전도도로부터 차폐효과를 정성적 수준에서 예측하는 연구를 수행하였다. 사용된 시편은 전도성 금속 (Cu, Ni)이 피복된 망사형 차폐재로 두께는 0.1 mm 정도이고, 전기전도도는 6.4 × 10~2.4 × 10(sup)5 mhos/m 범위 값을 가졌다. 물질상수와 시편의 두께로 표시되는 반사손실 및 흡수손실의 이론식을 도출하고 상기 시편에 대해 차폐효과를 계산하였다. 전도성 피복재의 경우 주된 차폐기구는 반사손실임을 밝힐 수 있었으며, 전기전도도가 증가함에 따라 차폐효과는 현저히 증가함을 알 수 있었다. 이들 이론치를 임피던스 실측치로부터 계산된 반사손실과 비교한 결과 10 dB 이내의 오차를 보임으로써 제안한 분석방법의 타당성을 입증하였다.

As an alternative evaluation method of electromagnetic shielding properties, the material parameters are considered in determining the qualitative value of shielding effectiveness. The specimens are metallized nylon fabrics with the thickness of about 0.1 mm and the electrical conductivities in the range from 6.4 × 10~2.4 × 10(sup)5 mhos/m. On the basis of shielding theory, the shielding effectiveness (which is a sum of reflection loss and absorption loss) has been determined from the material parameters of the barrier sheets. For the conductive fabrics, the dominant shield mechanism is predicted to be reflection loss, which shows an increasing function of electrical conductivity. Comparing these theoretical value with the directly measured surface impedances, the error range is found to be within 10 dB, which demonstrates that the proposed material-parameters method can be a convenient way to determine the electromagnetic shielding properties.

[References]

White DRJ, Mardiguian M, Interference Control Tech. Inc, 3 (1988)
Ott HW, Noise Reduction Techniques in Electronic Systems (1975)
Attenuation measurements for enclosures, electromagnetic shielding, for electronic test purposes, Method of U.S. DoD, MIL-STD-285/ 1956 (1956)
Emergency Standard Test Methods for Measuring th Electomagnetic Shielding Effectiveness for Planar Materials, ASTM ES7-83/ 1983 (1983)
Standard Test Method for Measuring the Electromagnetic Shielding Effectiveness for Planar Materials, ASTM D4935-89/ 1989 (1989)
정연춘, 강태원, 정낙삼, 전자파기술, 4(3), 45 (1993)
Schelkunoff SA, Electromagnetic Waves/ Van Nostrand, 1943 (1943)

[Referenced By]

[1] White DRJ, Mardiguian M, Interference Control Tech. Inc, 3 (1988)

[2] Ott HW, Noise Reduction Techniques in Electronic Systems (1975)

[3] Attenuation measurements for enclosures, electromagnetic shielding, for electronic test purposes, Method of U.S. DoD, MIL-STD-285/ 1956 (1956)

[4] Emergency Standard Test Methods for Measuring th Electomagnetic Shielding Effectiveness for Planar Materials, ASTM ES7-83/ 1983 (1983)

[5] Standard Test Method for Measuring the Electromagnetic Shielding Effectiveness for Planar Materials, ASTM D4935-89/ 1989 (1989)

[6] 정연춘, 강태원, 정낙삼, 전자파기술, 4(3), 45 (1993)

[7] Schelkunoff SA, Electromagnetic Waves/ Van Nostrand, 1943 (1943)