有源惠更斯超构表面对电磁波的动态波束调控及应用研究

Huygens’ metasurfaces have the ability to arbitrarily control the electromagnetic wave propagation with the properties of low-reflection and high-transmission, showing advantage of high-efficiency in transmission-type electromagnetic wave control, which have been used in many application such as beam shaper, lens, antenna, etc. However, active Huygens’ metasurfaces and their relevant electromagnetic devices are still in the early stage. To this end, this project aims to incorporate active electronic elements into the Huygens’ metasurface design, forming the active Huygens’ metasurface with optimized and excellent performances. Based on these active Huygens’ metasurfaces, we present a detailed design and optimization method to dynamically control the electromagnetic beams using active Huygens’ metasurfaces, which can manipulate the electromagnetic wave transmission in real-time with high-flexibility and high-efficiency. Then, we design and fabricate several functional devices with tunable functionalities such as dynamic beam scanning, beam forming and multi-beam forming, etc. The study in this project is not only very important for promoting the development of the theory of metasurface and mechanism of the dynamic wave control, but also essential to design and manufacture tunable Huygens’ metasurface devices, which can be further used in applications such as miniature and low-cost communication systems, detection systems, etc.

惠更斯电磁超构表面在具备超构表面对电磁波任意调控功能的同时，具有低反射、高透射的优点，因而在电磁波透射调控中具有明显优势，已应用于波束调控、聚焦透镜和天线设计等方面。然而，有源式惠更斯超构表面和相关有源器件的研究还尚处于起步阶段。为此，本项目旨在将有源可调元件融入到惠更斯超构表面的设计与分析中，优化并形成综合性能优异的有源惠更斯超构表面，从而建立惠更斯超构表面可调控器件设计的基础。进而建立基于有源惠更斯超构表面的电磁波波束动态调控的完整设计理论和具体实现方法，实现对透射电磁波的实时动态、灵活、高效调控，并研制出可以应用于动态波束扫描、波束赋形、多波束形成等动态调控的多种可调功能器件。本项目的研究不仅对丰富超构表面的理论体系、突破现有电磁波动态调控机制具有重要理论意义，而且对有源惠更斯超构表面的应用研制也具有重要的促进作用，有望在小型化、低成本通信和探测系统等领域发挥重要作用。

随着科学技术的发展，通信、探测等系统越加趋于小型化、共面化、系统化、集成化。这对电磁波调控器件提出了较高要求，简化系统和降低成本成了实际的迫切需求，因此如何在有限的空间内，实现高效地动态电磁波调控成了关键问题。超构表面在此背景下应运而生，它由亚波长单元按照特定的空间排布方式组成。有源惠更斯超构表面可实现灵活、动态的透射电磁波调控。本项目中，研究了一般有源元件等效电路模型参数的实验拟合方法，为后续有源电磁超构表面设计及其实验工作提供基础保障。建立多层级联式惠更斯超构表面的理论分析方法，研究一般条件下的电磁表面张量形式，推导了具有一般性的多层级联惠更斯超构表面设计方法，并进行相关器件设计与验证。分析实现远场特定波束对超构表面相位分布的要求，并提出了离散相位分布条件下的分析和优化方法。研究了平面型有源惠更斯超构表面并实现电磁波束扫描及动态调控，在此基础上，进一步拓展至全空间电磁波动态调控，提出全空间透反一体有源惠更斯超构表面，可灵活、动态工作于反射模式或惠更斯透射模式。最后，针对机械可重构超构表面，也探索其在动态电磁波调控中的应用。本项目的顺利开展有助于丰富电磁波调控手段，相关研究成果在成像、通信等领域具有应用前景。