【摘要】 研究了电磁缺陷修复材料在飞行器边缘、缝隙等表面电磁缺陷散射控制中的应用,阐述了其原理和发展状况。给出了表面电磁缺陷的基本定义,分析了其散射特点,并提出电磁缺陷修复原理及基本方法。电磁缺陷修复材料主要包括用于表面波抑制的磁性材料、用于窄缝隙保证电连续的导电材料和用于边缘散射控制的渐变阻抗材料等三类,重点介绍了用于边缘散射控制的渐变阻抗材料。该渐变阻抗材料基于图形渐变频率选择表面的概念,加载于边缘考虑平行极化和垂直极化两种情况,并与边缘锯齿化和未加载情况进行比较。从研究情况来看,经过恰当的材料选取和合理的阻抗梯度设计,渐变阻抗材料可以有效控制边缘散射,并能取得宽带效果。最后展望了渐变阻抗材料在电磁散射及电磁辐射领域的应用前景。更多还原

【Abstract】 The theory,application and development of electromagnetic discontinuities repairing materials in scattering controlling of electromagnetic discontinuities such as edge,gaps and grooves and steps are described. The definition and characteristic of surface electromagnetic discontinuities are analyzed,and the theory and methods for repairing electromagnetic discontinuities are also proposed. Electromagnetic discontinuities repairing materials including magnetic materials for suppression of surface wave,conductive materials for repairing the narrow gaps or grooves,and the tapered impedance materials for controlling edge scattering are discussed respectively,and one of which,the tapered impedance materials are illustrated particularly. The tapered resistive materials realized by geometric variation based on frequency-selective surfaces concepts is demonstrated having good suppression of edge scattering from a triangular metallic plate. Electromagnetic backscattering of the as-prepared target from a triangular plate with edge tapered resistive sheet loading is proposed for both horizontal polarization and vertical polarization,and compared with that from the one of the same shape but loaded with serrated shaping or none resistive sheet on the edge. The results show that the tapered impedance materials can regulate effectively edge scattering by choosing the appropriate materials and devising the reasonable gradient impedance. Some viewpoints of the tapered impedance material’s future application in electromagnetic scattering and electromagnetic radiation domains are proposed.更多还原