Browse > Article
http://dx.doi.org/10.5515/KJKIEES.2014.25.9.938

Improved ILDC Formulation for Very Thin Gap/Crack  

Lee, Hyunsoo (Department of Electronic Engineering, Inha University)
Koh, Il-Suek (Department of Electronic Engineering, Inha University)
Publication Information
The Journal of Korean Institute of Electromagnetic Engineering and Science / v.25, no.9, 2014 , pp. 938-943 More about this Journal
Abstract
The scattered field by a gap/crack on the PEC surface of a large object having low-observable RCS cannot be negligible, but may not be analyzed by the known high-frequency technique. If the electrical width of the crack is very small, the crack can be modeled by an impedance strip, whose scattering formulation can be analytically obtained based on a low-frequency approximation. The scattering solution is formulated for the 2D strip and TE(Transverse Electric) or TM(Transverse Magnetic) wave incidence, from which a 3D ILDC(Incremental Length Diffraction Coefficients) can be extracted. Using the ILDC formulation, the scattering by any arbitrary shaped crack can be estimated. In this paper, an improved ILDC equations are proposed, which combine the known TE and TM solutions. The improved accuracy of the proposed solution is numerically verified.
Keywords
Gap and Crack; RCS; ILDC; Low-Frequency Approximation;
Citations & Related Records
연도 인용수 순위
  • Reference
1 K. Barkeshli, J. Volakis, "Scattering from narrow rectangular filled grooves", IEEE Trans. Antennas Propagot., vol. 39, no. 6, pp. 804-810, Jun. 1991.   DOI
2 R. Cinoi, S. Sensani, G. D. Mauro, and A. Sarri, "Use of numerical ILDC in RCS design optimization loop", Radar Conference, 2008. RADAR '08. IEEE, pp. 1-6, May 2008.
3 R. Shore, A. Yaghjian, "Incremental diffraction coefficients for planar surfaces", IEEE Trans. Antennas Propagot., vol. 36, no. 1, pp. 55-70, Jan. 1988.   DOI
4 G. James, Geometrical Theory of Diffraction for Electromagnetic Waaves, IET, 1986.
5 T. Senior, Z. J. Volakis, Approximate Boundary Conditions in Electromagnetics, IEE, pp. 138-154, 1995.
6 C. Ozdemir, Inverse Synthetic Aperture Radar Imaging with MATLAB Algorithms, Wiley, 2012.
7 X. Zhu, J. Jin, "Approximate calculation of scattered field from three-dimensional narrow cracks", J. Electromagn. Waves Appl., vol. 13, pp. 3-24, 1999.   DOI
8 J. Jin, S. Ni, and S. Lee, "Hybridization of SBR and FEM for scattering by large bodies with cracks and cavities", IEEE Trans. Antennas Propagat., vol. 43, no. 10, pp. 1130-1139, Oct. 1995.   DOI
9 J. Jin, F. Ling, S. T. Carolan, J. M. Song, W. C. Gibson, W. C. Chew, C. C. Lu, and R. Kipp, "A Hybrid SBR/ MoM technique for analysis of scattering from samll protrusions on a large conducting body", IEEE Trans. Antennas Propagot., vol. 46, no. 9, pp. 1349-1357, Sep. 1998.   DOI   ScienceOn
10 T. Senior, J. Volakis, "Scattering by gaps and cracks", IEEE Trans. Antennas Propagot., vol. 37, no. 6, pp. 744-750, Jun. 1989.   DOI
11 T. Senior, K. Sarabandi, and J. Natzke, "Scattering by a narrow gap", IEEE Trans. Antennas Propagot., vol. 38, no. 7, pp. 1102-1110, Jul. 1990.   DOI