基于MLFMA的飞行器锯齿边板散射特性分析

为精确求解散射问题,采用混合场积分方程、多层快速多极子算法(MLFMA, Multilevel Fast Multipole Algorithm)和共轭梯度算法的迭代技术,并改进了多极子模式数.金属球双站雷达散射截面(RCS,Radar Cross Section)的算例表明,该方法在保证精度的前提下,降低了内存和计算时间;分析了锯齿边板的电磁散射特性,总结了锯齿边板相对于直边板在不同角域内的RCS减缩特性以及RCS减缩与入射频率变化之间的关系:随着入射频率的增高,RCS减缩效果迅速提高,且垂直极化减缩效果较水平极化减缩效果好.该结论可以用来提高飞行器的隐身性能. 

Analysis of scattering from serrated edge plate on aircraft with MLFMA

Combined field integral equation(CFIE),multilevel fast multipole algorithm(MLFMA) and conjugate grads method(CGM) were employed,and a modified truncation number had been presented to gain the precise scattering from objects efficiently and stably.It was exemplified that this new method could reduce memory and computation time at the same accuracy by its application to the bistatic radar cross section(RCS) of sphere.Scattering from serrated edge plates was analyzed.The problem how the RCS reduction of serrated edge plate changes against straight edge plate was discussed in different angle range.The connection between the RCS reduction and incident frequency was also discovered.Results show that the RCS reduction of serrated edge plate increases sharply when the incident frequencies become larger,the RCS reduction effect in vertical polarization is greater than that in horizontal polarization.This conclusion can find its application to improve the stealth performance of aircraft.