In this article, we propose nonperiodic metasurfaces used for retroreflection of oblique incident wave with linear polarization (TE/TM) and circular polarization (CP). For CP wave, both handedness reversal and handedness preservation cases are demonstrated. The proposed metasurfaces consist of nonperiodic group cells optimized by genetic algorithm for desired scattered power patterns. Each group cell includes several locally periodic elements that are characterized by their reflection phase response under TE/TM or CP illumination. The proposed metasurfaces for retroflection have achieved reduced sidelobe level and suppressed specular beam and are verified by both full wave simulation and measurement at 10 GHz. This nonperiodic metasurface design method offers fast implementation for retroreflection of any plane wave with easy planar fabrication and can be easily scaled to millimeter-wave, THz, and optical regimes.

中文翻译：

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用于回射 TE/TM 和圆偏振波的非周期性超表面

在这篇文章中，我们提出了用于逆向反射具有线性偏振 (TE/TM) 和圆偏振 (CP) 的斜入射波的非周期性超表面。对于 CP 波，显示了惯用性逆转和惯用性保留案例。所提出的超表面由通过遗传算法优化的非周期性群单元组成，以获得所需的散射功率模式。每个组单元包括几个局部周期元素，其特征在于它们在 TE/TM 或 CP 照明下的反射相位响应。所提出的用于回射的超表面已经实现了降低的旁瓣水平和抑制的镜面光束，并通过全波模拟和 10 GHz 的测量进行了验证。