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IEEE Transactions on Antennas and Propagation
Volume 46 Number 9, September 1998

Table of Contents for this issue

Complete paper in PDF format

A Hybrid SBR/MoM Technique for Analysis of Scattering from Small Protrusions on a Large Conducting Body

Jian-Ming Jin, Senior Member, IEEE, Feng Ling, Student Member, IEEE, Shawn T. Carolan, Jiming M. Song, Member, IEEE, Walton C. Gibson, Weng Cho Chew, Fellow, IEEE, Cai-Cheng Lu, Member, IEEE, and Robert Kipp, Member, IEEE

Page 1349.

Abstract:

A hybrid technique combining the shooting-and-bouncing-ray (SBR) method and the method-of-moments (MoM) is presented for analyzing scattering by large conducting bodies having small protrusions. In this technique, the MoM with an approximate Green's function is used to characterize the small protrusions, yielding an admittance matrix, which, when multiplied with the incident field on the protrusions, yields the currents induced on the protrusions. The incident field in the presence of the large bodies is calculated using the SBR method. The field radiated by the currents on the protrusions is also calculated using the SBR method with the aid of reciprocity. Furthermore, an iterative approach is developed, which can reduce the error introduced by the use of the approximate Green's function. Numerical results are given to demonstrate the accuracy and capability of the hybrid technique.

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