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

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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Electromagnetic Wave Scattering from a Perfectly Conducting Fractional Brownian Motion Fractal Surface Using a Monte-Carlo FDTD Method

몬테칼로 유한차분 시간영역 방법을 이용한 프랙셔널 브라운 모션 프랙탈 완전도체 표면에서의 전자파 산란

  • 최동묵 (경북대학교 공과대학 전자공학과) ;
  • 김채영 (경북대학교 공과대학 전자공학과)
  • Published : 2003.02.01
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Abstract

In this paper, the scattered field from a perfectly conducting fractal surface by Finite-Difference Time-Domain(FDTD) method was computed. A one-dimensional fractal surface was generated by using the fractional Brownian motion model. Back scattering coefficients are calculated with different values of the spectral parameter(S0), fractal dimension(D) which determine characteristics of the fractal surface. The number of surface realization for the computed field, the point number, and the width of surface realization are set to be 80, 1024, 16λ, respectively. In order to verify the computed results these results are compared with those of small perturbation methods, which show good agreement between them.

본 논문에서는 몬테칼로 유한차분 시간영역 해석법을 이용하여 프랙탈 형상을 가진 완전 도체 표면에서 산란된 장을 구하였다. 프랙탈 형상을 가진 1차원 표면은 프랙셔널 브라운 모션 모델을 사용하여 생성하였다. 프랙탈 표면의 형상을 결정하는 스펙트럼 변수(S0), 프랙탈 차원(D)에 대한 역방향 산란계수를 계산하였다. 계산에 사용된 표면의 수는 80개, 표면의 점의 수는 1024개이고, 표면의 길이는 16파장이었다. 계산된 결과의 타당성을 검증하기 위해 소 섭동 근사기법을 이용하여 계산된 결과와 비교하였다. 그 결과 양자간의 결과는 서로 잘 일치함을 알 수 있었다.

Keywords

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