Development of Electromagnetic Wave Absorbers far Mobile Phone Using Sendust

Sendust를 이용한 휴대전화용 전파 흡수체의 개발

  • Choi Jung-Hyun (Dept. of Radio Sciences & Eng., Korea Maritime University) ;
  • Kim Dong-Il (Dept. of Radio Sciences & Eng., Korea Maritime University) ;
  • Song Jae-Man (Research Institute of Industrial Technology, Korea Maritime University) ;
  • Jung Jae-Hyun (Dept. of Radio Sciences & Eng., Korea Maritime University)
  • 최정현 (한국해양대학교 전파공학과) ;
  • 김동일 (한국해양대학교 전파공학과) ;
  • 송재만 (한국해양대학교 산업기술연구소) ;
  • 정재현 (한국해양대학교 전파공학과)
  • Published : 2005.08.01

Abstract

In this paper, we fabricated sheet-type EM wave absorbers for mobile phones by using sendusts and tested EM wave absorption of it. The band-width of EM wave absorbers coated with $Al_2O_3$ were larger than non-coated EM wave absorbers. Particle size decreased with increasing milling time, which made the result of increasing of EM wave absorption. The fabricated EM wave absorbers show a reflection coefficient 17.4 dB at 946 MHz for a 4 mm sample and 5 dB at 1.8 GHz for a 1 mm sample.

본 논문에서는 시편의 두께와 $Al_2O_3$ 함유량, 분쇄시간에 따른 입자 크기가 Sendust를 이용한 sheet형 전파 흡수체 의 전파 흡수능에 미치는 영향을 조사한 것이다. $Al_2O_3$를 코팅한 전파 흡수체는 코팅하지 않은 전파 흡수체와 비교할 때 흡수 대역이 넓어지고, 분쇄 시간이 증가함에 따라 입자 크기가 작아지고 이로 인해 전파 흡수능이 증가함을 확인하였다. 제작된 전파 흡수체의 두께가 4 mm일 때 946 MHz에서 17.4 dB, 1 mm일 때 1.8 GHz에서 약 5 dB의 전파 흡수능을 나타내었다.

Keywords

References

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