Metasurfaces, as two dimensional periodic structures, are an important candidate to manipulate the polarization of electromagnetic (EM) waves. However, there are few reports on the simultaneous realization of wideband dual-circular polarization conversion using transmissive metasurfaces with one periodic structure in measurement. In this paper, we propose a dual-band dual-circular transmissive metasurface (DCT-MS) for polarization conversion. A DCT-MS simultaneously converts linearly polarized (LP) EM waves into left-hand circularly polarized (LHCP) EM waves in a lower band and right-hand circularly polarized (RHCP) EM waves in a higher band. The unit cell of a DCT-MS consists of a thin substrate and two metal patches in the shape of symmetrical arrows above and below the substrate. The simulated results show that LP waves can be converted into LHCP waves from 7.31 GHz to 10.58 GHz with the axial ratio less than 3 dB. Moreover, the RHCP waves can be realized from 14.26 GHz to 17.36 GHz with the same standard. A DCT-MS sample is measured, and the experimental results are in good agreement with the simulation results.

中文翻译：

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同时进行线性到双圆偏振转换的双波段透射超表面

作为二维周期性结构的超表面是操纵电磁波（EM）极化的重要候选者。但是，关于在测量中使用具有一个周期性结构的透射超表面同时实现宽带双圆偏振转换的报道很少。在本文中，我们提出了一种用于偏振转换的双波段双圆透射超表面（DCT-MS）。DCT-MS同时将线性极化（LP）EM波转换为较低频带中的左旋圆极化（LHCP）EM波和较高频带中的右旋圆极化（RHCP）EM波。DCT-MS的晶胞由一个薄的基板和两个在基板上方和下方呈对称箭头形状的金属贴片组成。仿真结果表明，在轴向比小于3 dB的情况下，LP波可以从7.31 GHz转换为10.58 GHz的LHCP波。而且，可以以相同的标准在14.26 GHz至17.36 GHz范围内实现RHCP波。测量了DCT-MS样品，实验结果与仿真结果吻合良好。