摘要
对隐身飞行器、坦克等武器系统,缝隙等不连续特征对RCS的减缩和控制具有重要影响。基于混合场积分方程,开发出了多层快速多极子算法程序,通过将金属球双站RCS级数解、三缝隙实测曲线分别与多层快速多极子算法(Multilevel Fast Multipole Algorithm,MLFMA)计算曲线进行对比,验证了程序的正确性,说明其可用于飞行器表面不连续特征研究。采用数值方法详细研究了单缝隙、三缝隙电磁散射与入射电磁波频率的变化关系。数值计算结果表明,入射电磁波频率增加时,对单缝隙,电磁散射增强,雷达散射截面算术均值增加,其中掠入射角域内的均值增加最为明显;同时单缝隙的散射曲线相似、次波峰向外偏移;对三缝隙,除具有单缝隙的特性外,还表现为相互耦合性、曲线振荡增强,通过分析认为3个单缝隙散射不同相位的相互叠加导致了其散射的耦合性,入射频率增加时,散射叠加的峰值位置发生相应变化,表现为耦合作用和振荡作用更加明显。该结论可以用来进行飞行器表面的缝隙散射的减缩设计,从而有效提高飞行器的隐身性能。
For stealth aircrafts and tanks, the discontinuous characters such as gaps are important for RCS （Radar Cross Section） reduction and control. Basing on CFIE （ Combined Field Integral Equation）, a program using MLFMA （ Multilevel Fast Multi - pole Algorithm） is developed. The bistatic RCS of metal sphere by Mie series solution and the experimental curves of a multi - gap plate are compared with computational curves to validate the correctness of this program which shows that the program can be used in investigating the scattering from discontinuous characters in aircraft surface. The relation of single - gap, three - gap and incoming frequency is researched by MLFMA. When the incoming frequency is greater, numerical results show that the electromagnetic scattering enhances and the RCS arithmetic average increases for single - gap and multi - gap; when the incoming angle is small, the average value increases fast, for single - gap plate, the curves are similar for different frequencies and the second crest of curve moves far away from the major crest, scattering from multi - gap has coupling performance and the curves change sharply beside the characteristic of single - gap plate. The coupling performance is gained by the superposition of different phases of three single - gaps, when frequency increases, the position of scattering superposition changes, at the same time, the effects of couple and surge will be obvious. This conclusion can find its application in the design of reducing the RCS of scattering from the gaps in aircraft surface and thus improve the stealth performance of aircraft.
出处
《空军工程大学学报（自然科学版）》
CSCD
北大核心
2009年第2期60-65,共6页
Journal of Air Force Engineering University(Natural Science Edition)
基金
国家“973”基础研究资助项目(61320)
关键词
多层快速多极子算法
电磁
散射
雷达散射截面
多频
multilevel fast multi - pole algorithm
electromagnetic
scattering
radar cross section
multi - waves
