The Journal of Korean Institute of Communications and Information Sciences (한국통신학회논문지)

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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Embodiment of High Impedance Surface of Meta-Material Characteristic Using Symmetrical AMC Structure and Its SAR Analysis

대칭형 인공자기도체 구조를 이용한 메타물질 특성의 고임피던스 표면 구현 및 SAR 특성 분석

  • 이승우 (충북대학교 전자정보대학 정보통신공학부) ;
  • 이명희 (충북대학교 전자정보대학 정보통신공학부) ;
  • 이승엽 (전남대학교 전기.전자통신.컴퓨터공학부) ;
  • 김남 (충북대학교 전자정보대학 정보통신공학부)
  • Received : 2013.07.11
  • Accepted : 2013.08.09
  • Published : 2013.09.30
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Abstract

In this paper, we proposed new type of an artificial magnetic conductor(AMC) structure, which has a high impedance surface for realizing the meta-material characteristics. The designed AMC structure set a goal of 3.2GHz, and the reflector, which consists of periodically arrayed AMCs is fabricated and measured. The high impedance improves the reflection coefficient, decreases the system size and interference, and increases the antenna performance. The structure has embodied the high impedance by the thickness and relative permitivity of the dielectric substrate and the design configuration without the metallic via hole which connects the AMC to the GND. The bandwidth is 150% broader than the similar AMC structures. Also, the distance between the antenna and the AMC reflector is decreased by ${\lambda}/10$ as working as the metal(PEC) reflectors. The antenna radiation characteristics are 3dB increased at 10mm away from reflector by measurement. The proposed reflector could be inserted in the portable mobile devices, and the antenna's performance has improved by the reflector. The specific absorption rate is dramatically decreased over 94% because the back radiation of the antenna is shielded.

본 논문에서는 메타물질 특성을 구현하기 위하여 고임피던스 표면을 갖는 인공자기도체(AMC) 구조를 제안하였다. 설계한 AMC 구조는 3.2GHz에 적용하는 것을 목표로 하였으며, 특성 분석을 위해 다중의 AMC 구조를 일정하게 배열한 반사판으로 제작 및 측정하였다. AMC 반사판의 표면에 형성되는 높은 임피던스로 인하여 반사 특성이 좋아지고, 간섭 및 시스템의 크기를 줄이며, 안테나의 성능을 증가시킨다. 제안된 구조는 설계된 AMC와 접지면을 잇는 via hole을 사용하지 않고, 유전체의 두께와 유전율, 구조의 특성을 이용하여 고임피던스를 구현하였다. 기존의 연구된 via hole이 없는 구조와 비교하여 대역폭이 약 150% 증가하였다. 또한, 금속(PEC) 반사판과 동일한 반사특성을 보이는 대신, 안테나와 반사판 간의 거리를 ${\lambda}/10$까지 줄일 수 있다. 실험을 통하여 안테나와의 거리가 약 10mm 지점에서 방사 특성이 3dB 증가한 것을 확인하였다. 설계된 반사판은 반사거리가 작아 휴대용 무선통신기기의 내부에 삽입이 가능하며, 안테나의 효율을 증가시키고, 후방 방사를 차폐함으로써 전자파인체흡수율을 94% 이상 획기적으로 감소시킬 수 있다.

Keywords

References

  1. D. Sievenpiper, L. Zhang, R. F. J. Broas, N. G. Alexopolous, and E. Yablonovitch, "High-impedance electromagnetic surfaces with a forbidden frequency band," IEEE Trans. Microw. Theory Tech., vol. 47, no. 11, pp. 2059-2074, Nov. 1999. https://doi.org/10.1109/22.798001
  2. S. Lee, N. Kim, and S. Rhee, "Embodiment of high impedance surface using artificial magnetic conductor with periodically rectangular lattices," Microwave Optical Technol. Lett., vol. 55, no. 2, pp. 366-368, Feb. 2013. https://doi.org/10.1002/mop.27339
  3. J. R. Sohn, K. Y. Kim, H. S. Tae, and H. J. Lee, "Comparative study on various artificial magnetic conductors for low-profile antenna," Progress in Electromagnetics Research (PIER), vol. 61, pp. 27-37, June 2006.
  4. A. P. Feresidis, G. Goussetis, S. Wang, and J. C. Vardaxoglou, "Artificial magnetic conductor surfaces and their application to low-profile high-gain planar antennas," IEEE Trans. Antennas Propag., vol. 53, no. 1, pp. 209-215, Jan. 2005. https://doi.org/10.1109/TAP.2004.840528
  5. J. Sarrazin, A. C. Lepage, and X. Begaud, "Dual-band artificial magnetic conductor," Applied Physics A, vol. 109, no. 4, pp. 1075-1080, Dec. 2012. https://doi.org/10.1007/s00339-012-7409-1
  6. S. K. Hampel, O. Schmitz, O. Klemp, and H. Eul, "Design of Sievenpiper HIS for use in planar broadband antennas by means of effective medium theory," Advances in Radio Sci., vol. 5, pp. 87-94, June 2007. https://doi.org/10.5194/ars-5-87-2007
  7. G. Niyomjan and Y. Huang, "Investigation of high impedance surface structure with different patch shapes using a new improved enhanced effective medium method," in Proc. Int. Workshop Antenna Technol, 2008 (iWAT'08), pp. 187-190, Chiba, Japan, Mar. 2008.
  8. M. Imbert. P. J. Ferrer, J. M. Gonzalez-Arbesu, and J. Romeu, "Design of a bidirectional metamaterial spacer at 2.45 GHz," in Proc. European Antenna Propagation (EuCAP'10), pp. 1-5, Barcelona, Spain, Apr. 2010.
  9. S. Lee, N. Kim, Y. Shin, and J. Jang, "Study on reduction of specific absorption rate of 2.4 GHz dipole antenna by using novel artificial magnetic conductor's reflector," in Proc. Asia-Pacific Microwave Conf. (APMC 2012), pp. 592-594, Kaohsiung, Taiwan, Dec. 2012.
  10. M. K. T. Al-Nuaimi and W. G. Whittow, "Novel Planar AMC for Low Profile Antenna Applications," in Proc. Loughborough Antenna Propagation Conf. (LAPC 2009), pp. 145-148, Loughborough, U.K., Nov. 2009.
  11. I. Tomeo-Reyes and E. Rajo-Iglesias, "Comparative study on different AMC ground planes and its applications to low profile wire antennas," in Proc. IEEE Antennas Propagation Soc. Int. Symp. 2009 (APSURSI'09), pp. 1-4, Charleston, U.S.A., June 2009.
  12. S. Lee, S. Y. Rhee, P. Y. Kim, and N. Kim, "Realization of high impedance surface characteristics using a periodically transformed artificial magnetic conductor structure and reduction technique of specific absorption rate," J. Electromagnetic Eng. Sci., vol. 13, no. 2, pp. 113-119, June 2013. https://doi.org/10.5515/JKIEES.2013.13.2.113
  13. SPEAG, SEMCAD X, Retrieved August 1, 2012 from www.speag.com.