FDTD Analysis of a Monopole Antenna on the Ground Plane with Ferrite Material Locally

부분적으로 페라이트 재질을 갖는 접지면상에서 모노폴안테나의 FDTD 해석

  • 임계재 (관동대학교 IT학부 정보통신전공)
  • Published : 2003.12.01

Abstract

For the reduction of electromagnetic biological effects from cellular phones, the electrical field radiation from cellular phone antenna is reduced by using partial ferrite material added on the phone case as ground plane. On the given properties (permittivity, permeability and conductivity) of ferrite material, the characteristics of monopole antenna is analysed depending on the variation of ferrite added configuration(thickness and shape). According to this analysis, the design method and direction to minimize the biological effects to human head is proposed in 1.7 GHz band PCS phones. For the exact analysis involving the permittivity, per-meability and conductivity of ferrite material, FDTD numerical method is used.

휴대폰 안테나로부터의 전자파 인체영향을 저감시키기 위해, 접지면으로 작용하는 휴대폰 본체표면에 부분적으로 페라이트 재질을 부가하여 인체두부 방향으로의 복사 전기장세기를 저감시켰다. 페라이트의 재질특성(유전율, 투자율, 도전율)이 주어졌을 때, 구조(두께, 부가부위)의 변화에 따른 영향을 모노폴안테나 모형에 적용함으로써 1.7 GHz 대역 PCS 휴대폰 설계시 인체영향을 최소화할 수 있는 방향을 제시할 수 있었다. 해석방법으로는 물질의 유전을 및 도전율, 투자율 특성을 고려한 FDTD 수치해석 방법을 사용하였다.

Keywords

References

  1. FCC OET 65. 1997: Evaluating Compliance with FCC Specified Guideline for Human Exposure to RadioIrequency radiation, OET Bulletin 65
  2. jensen, M.A., and Rahmat-Samii, Y, 1995: EM interaction of handset antennas and a human in personal communications, Proc. of the IEEE, 83(1), pp. 7-17 https://doi.org/10.1109/5.362755
  3. Gandhi, O.R, and Chen, J., 1995: Electromagnetic absorption in the human head from experimental 6-GHz handheld transceivers, IEEE Trans. on EMC, 37(4), pp. 547-558
  4. Balzano, Q., Garay, O., and Manning, T.J., 1995: Electro-magnetic energy exposure of simulated users of potable cellular telephones, IEEE Trans. on VT, 44(3), pp. 390-402
  5. Gandhi, O.P., Lazzi, G., Furse, C.M., 1996: Electromagnetic absorption in the human head and neck for mobile telephones at 835 and 1900 MHz, IEEE Trans. on MTT, 44(10), pp. 1884-1897 https://doi.org/10.1109/22.539947
  6. Takeshi OHSHMA, Eri TAKAHASHI, Jianqmg WANG, and Osamu FUJIWARA. 2002: Verification of Electromaenetic Interference Testing of Cardiac Pace-makers by Portable Terminals with an MRl-Based AnatomicaI Human Modet, 電子情報通信學會論文紙, 2002/12 J85-B(12), pp. 2419-2421
  7. Yang, W.G., Lee, K.H., and Kong, S.S., 2002: Simulation and measurement of SAR with folder angle variation and SAR reduction with EMl paint for mobile handset, Proc. of North-east Asia Symp. 2002, PP. 569-572
  8. Kim, K.H., Hong, S.W., and Oh, H.T, 2001: SAR variations by EMl condition of cellular phone case, Proc. of WHO meeting on EMF Biological effect & Standard Harmonization in Asia and Oceania, pp. 115
  9. Kunz, K.S., Luebbers, R.J., 1993: The Finite Difference Time Domain method for Electromagnetics, CRC Press, pp. 11-49
  10. Melvin, M., and Weiner. 2003: Mompole Antennas, Marcel Dekker Inc. New York, pp. 21-24
  11. Jianqing wans, and Osamu fujiwara. 1999: Effects of Ferrite Sheet Attachment to Portable Tetephone in Reduction EIectromagnetic Absorption in Human Head, IEEE ISEC, 2, pp. 822-825
  12. Yee, K..S., 1966: Numerical solution of initial boundary value problems involving Maxwell's equations in isotropic media, IEEE Trans. on AP., 14, PP. 302-307 https://doi.org/10.1109/TCOM.1966.1089323