Abstract：The influence of minor geometrical features on vehicle surfaces on the radar stealth characteristics was analyzed in simulations. Numerical analyses of the electromagnetic scattering characteristics were conducted using a simplified vehicle side door with minor seams, grooves and convex geometrical features (bullet-proof glass and a metal bar for a door-seal). The results show that these minor uneven surface features negatively affect the body's radar cross section (RCS) characteristics. The numbers of incidence angles for the RCS area greater than 10 dBsm for the simplified vehicle side doors with minor seams and grooves are up to 2.2 and 2.8 times that of a smooth metal plate. The number of incidence angles for the RCS area greater than 10 dBsm for an armored vehicle side door with bullet-proof glass is 5.4 times greater while that with a metal bar seal is 1.7 times greater. Electromagnetic scattering experiments using a rectangular aluminum plate with a rectangular aluminum bar frame on one side show that the bar frame increases the plate's RCS area. Thus, even minor uneven surface features on a vehicle body increase the numbers of incidence angles for the RCS area greater than 10 dBsm, although they have less influences on the maximum peak RCS area. Therefore, exterior surface seams, grooves and convex features should be avoided to improve the radar stealth characteristics.
孙洪海, 吕振华. 车身非平整表面的RCS分布特性数值模拟分析[J]. 清华大学学报（自然科学版）, 2018, 58(4): 424-431.
SUN Honghai, LÜ Zhenhua. Numerical analyses of the RCS characteristics of a vehicle body with concave/convex surface features. Journal of Tsinghua University(Science and Technology), 2018, 58(4): 424-431.
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