A dual-polarized (DP) metasurface (MTS) antenna with miniaturized radiating aperture is proposed for polarimetric synthetic aperture radar. The antenna consists of an MTS radiator and a cross aperture antenna. Characteristic mode analysis (CMA) is utilized to analyze the working mechanism of the MTS radiator and to guide the miniaturization of the radiating aperture. Then, the CMA is used for the optimization of the DP cross aperture antenna to achieve better isolation. A reduced radiating aperture of $0.37{\lambda _0} \times 0.36{\lambda _0}$ is realized with a thickness of $0.13{\lambda _0}$ ( ${\lambda _0}$ is the free-space wavelength of central frequency). The simulated and measured results show that the DP antenna yields 10 dB fractional bandwidths of 43.72% for Port H and 38.65% for Port V. The cross-polarization levels are better than –23 dB at 9.6 GHz, and the isolation between the two ports remains above 35 dB over the whole operating bandwidth.

中文翻译：

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高度隔离的小型化双极化超表面天线

提出了一种用于极化合成孔径雷达的具有最小化辐射孔径的双极化（DP）超表面（MTS）天线。天线由MTS辐射器和交叉孔径天线组成。特征模式分析（CMA）用于分析MTS散热器的工作机理，并指导辐射孔的小型化。然后，将CMA用于DP交叉孔径天线的优化，以实现更好的隔离。减小的辐射孔径$ 0.37 {\ lambda _0} \ times 0.36 {\ lambda _0} $ 厚度为 $ 0.13 {\ lambda _0} $ （ $ {\ lambda _0} $是中心频率的自由空间波长）。仿真和测量结果表明，DP天线对端口H产生10 dB的部分带宽，分别为端口H的43.72％和38.65％。在9.6 GHz频率下，交叉极化电平优于–23 dB，并且两个端口之间的隔离度在整个工作带宽上保持高于35 dB。