ABSTRACT An approach for improving the invisibility performance of mantle cloak is proposed. It is based on an interesting observation that the cloaking performance of mantle cloak can be significantly enhanced if the cloak is operated under tilted conditions with respect to the incident radiation (such that the wave is incident obliquely onto the cloak). The mantle cloak is thus designed by judiciously choosing the value of surface impedance corresponding to the tilt angle. It is because the optimum value of surface impedance changes with the tilt angle. An analytical method is devised for the calculation of optimum surface impedance under tilted conditions and subsequently verified with Ansys HFSS simulations. It is also shown that by deliberately tilting the mantle cloak, numerous advantages over normal incidence scenario, are obtained, such as (a) significant reduction in total scattering width, (b) considerable enhancement in bandwidth, and (c) increase in performance robustness with respect to the dispersion of surface impedance. These advantages of operating under tilted conditions are well elucidated by comparing it with that for normal incidence scenario previously presented in various literatures. The metasurface cloak is subsequently realized using I-shaped unit cell structure and varactor diodes, and cloaking performance is analyzed using HFSS simulations.

中文翻译：

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一种改进隐身性能的宽带斗篷斗篷的分析与实现

摘要 提出了一种提高披风斗篷隐身性能的方法。它基于一项有趣的观察，即如果斗篷在相对于入射辐射的倾斜条件下操作（例如波倾斜入射到斗篷上），则斗篷斗篷的隐身性能可以显着增强。因此，通过明智地选择与倾斜角相对应的表面阻抗值来设计地幔斗篷。这是因为表面阻抗的最佳值随倾角而变化。设计了一种分析方法来计算倾斜条件下的最佳表面阻抗，随后通过 Ansys HFSS 仿真进行验证。还表明，通过故意倾斜地幔斗篷，可以获得比正常入射情况更多的优势，例如 (a) 总散射宽度显着减少，(b) 带宽显着增强，以及 (c) 提高了对表面阻抗分散的性能鲁棒性。在倾斜条件下运行的这些优点通过与之前在各种文献中提出的正常入射场景的比较得到了很好的阐明。随后使用 I 形晶胞结构和变容二极管实现超表面隐形，并使用 HFSS 模拟分析隐形性能。在倾斜条件下运行的这些优点通过与之前在各种文献中提出的正常入射场景的比较得到了很好的阐明。随后使用 I 形晶胞结构和变容二极管实现超表面隐形，并使用 HFSS 模拟分析隐形性能。在倾斜条件下运行的这些优点通过与之前在各种文献中提出的正常入射场景的比较得到了很好的阐明。随后使用 I 形晶胞结构和变容二极管实现超表面隐形，并使用 HFSS 模拟分析隐形性能。