一种求解内谐振条件下导体散射特性的有效方法

An Effective Approach to Scattering from Conducting Bodies at Interior Resonance

众所周知,在内谐振条件下,用积分方程法分析导体的散射特性时,不论是电场积分方程还是磁场积分方程,所求得的解都是不唯一或者不稳定的。本文提出了一种新的方案,通过引入一个微小的复频率,并结合逼近理论求得导体表面的真实电流密度,从而得到正确的导体散射特性。此方法具有实现简单和概念清晰的优点。文中分别以无限长理想导体正方柱和两个理想导体球为例,并将计算结果与混合场积分方程法所得的结果进行比较,它们之间良好的一致性说明了本文所提方法的正确性和有效性。

As is well known, when the integral equation （IE） method is applied to analyze the scattering from conductors at interior resonances, either＂ E-field integral equations or H-field integral equations, the solutions are always nonunique or instable. A novel scheme is presented in the paper to deal with such problems. The method is developed to compute the true non-resonant current density of conductors by introducing a small complex frequency and by employing the approximation theory, which possesses the advantage of simplicity in implementation and clarify in concept. An infinite perfectly conducting square cylinder and two perfectly conducting spheres are taken as examples and the computed results are compared with those obtained by combined field integral equation （CFIE）. The good agreement between them shows the correctness and effectiveness of the proposed method.