等离子体目标宽频电磁散射特性的快速分析

Fast scattering analysis of plasma over a broad frequency band

针对等离子体宽频电磁散射特性分析的复杂性,提出了一种基于最佳一致逼近理论的宽频分析算法。该方法以获得切比雪夫级数逼近为基础,并转化为梅利逼近,使得计算精度大为改善。相比于传统的泰勒-帕德模式,其具有低内存、高精度、有效计算带宽大等优势,尤其在分析等离子体这种色散介质的宽频特性时,避免了复杂高阶阻抗矩阵导数的计算。通过不同实例的数值仿真分析,说明该方法可以作为一种分析等离子体目标宽频特性的有效工具。

Considering the scattering analysis complexity of plasma over a broad frequency band, a new frequency-sweep analysis method is proposed based on the best uniform approximation theory. In the proposed algorithm, the Chebyshev series are used to approximate the surface current, which is marched to be a rational function by Maehly method to improve the accuracy greatly. Compared with the traditional Taylor-Pade model in asymptotic waveform evaluation （AWE） technique, it can accomplish the scattering analysis accurately over a broader frequency band with lower memory consumption, especially for the frequency-sweep analysis of plasma which is usually a dispersive dielectric object, the proposed method can avoid complex computation of high order derivates for impedance matrix elements. Different numerical examples are discussed, and it is shown that the proposed method can be used as an efficient tool to analyze scattering characters of plasma over a broad frequency band.