Boyarsky Michael, Sleasman Timothy, Pulido-Mancera Laura, Fromenteze Thomas, Pedross-Engel Andreas, Watts Claire M, Imani Mohammadreza F, Reynolds Matthew S, Smith David R
J Opt Soc Am A Opt Image Sci Vis. 2017 May 1;34(5):A22-A36. doi: 10.1364/JOSAA.34.000A22.
We investigate the application of dynamic metasurface antennas (DMAs) to synthetic aperture radar (SAR) systems. Metasurface antennas can generate a multitude of tailored electromagnetic waveforms from a physical platform that is low-cost, lightweight, and planar; these characteristics are not readily available with traditional SAR technologies, such as phased arrays and mechanically steered systems. We show that electronically tuned DMAs can generate steerable, directive beams for traditional stripmap and spotlight SAR imaging modes. This capability eliminates the need for mechanical gimbals and phase shifters, simplifying the hardware architecture of a SAR system. Additionally, we discuss alternative imaging modalities, including enhanced resolution stripmap and diverse pattern stripmap, which can achieve resolution on par with spotlight, while maintaining a large region-of-interest, as possible with stripmap. Further consideration is given to strategies for integrating metasurfaces with chirped pulse RF sources. DMAs are poised to propel SAR systems forward by offering a vast range of capabilities from a significantly improved physical platform.
我们研究动态超表面天线（DMA）在合成孔径雷达（SAR）系统中的应用。超表面天线能够从一个低成本、轻质且平面的物理平台生成多种定制的电磁波形；而这些特性是传统SAR技术（如相控阵和机械转向系统）所不具备的。我们表明，电子调谐的DMA可为传统条带图和聚束式SAR成像模式生成可控的定向波束。这种能力消除了对机械万向节和移相器的需求，简化了SAR系统的硬件架构。此外，我们还讨论了替代成像模式，包括增强分辨率条带图和多样模式条带图，它们能够在保持条带图所具有的大感兴趣区域的同时，实现与聚束式相当的分辨率。还进一步考虑了将超表面与啁啾脉冲射频源集成的策略。DMA有望通过从显著改进的物理平台提供广泛的功能，推动SAR系统向前发展。
