人工电磁表面的多维度调控演进：“频率选择表面”到“智能电磁皮肤”

The Multi-Dimensional Regulation Evolution of Artificial Electromagnetic Surfaces: From Frequency-Selective Surfaces to Intelligent Electromagnetic Skins

摘要: 随着无线系统激增，空间电磁环境日趋复杂，如何在维持传播空间基本形态的前提下实现对特定频率、能量及传播状态电磁波的选择性调控，已成为现代电磁技术的关键问题。频率选择表面(FSS)由周期/准周期单元构成，利用单元谐振与耦合产生特定的反射与透射响应，被誉为空间中的“电磁滤波窗”。本文从电磁波传播和谐振基础理论出发，阐释FSS的空间滤波机理、等效电路模型及能量分配过程，并综述频率选择吸波体、可重构FSS及能量选择表面等衍生技术的发展。研究表明，人工电磁表面正从固定频率选择向吸收–透射协同、动态调谐、功率自适应及可编程多自由度调控演进，柔性基材、透明导电材料与印刷电子技术则为其轻量化、共形化与大面积制造提供了支撑。文章进一步探讨“智能电磁皮肤”的技术内涵，指出其本质并非单一FSS结构，而是由人工电磁单元、可调器件、环境感知、数字控制与算法决策集成的综合调控系统，有望推动电磁表面从被动滤波向主动感知与自适应调控跃升。

Abstract: With the rapid growth of wireless systems, the space electromagnetic environment has become increasingly complex. How to achieve selective control of electromagnetic waves of specific frequencies, energies, and propagation states while maintaining the basic form of the propagation space has become a key issue in modern electromagnetic technology. Frequency-selective surfaces (FSS) are composed of periodic/periodic units, and by using the resonances and couplings of these units to generate specific reflection and transmission responses, they are known as “electromagnetic filtering windows” in space. This paper starts from the basic theories of electromagnetic wave propagation and resonance, explains the spatial filtering mechanism, equivalent circuit model, and energy distribution process of FSS, and reviews the development of frequency-selective absorbing bodies, active reconfigurable FSS, and energy-selective surfaces and other derivative technologies. Research shows that artificial electromagnetic surfaces are evolving from fixed frequency selection to absorption-transmission synergy, dynamic tuning, power adaptation, and programmable multi-degree-of-freedom control. Flexible substrates, transparent conductive materials, and printed electronic technologies provide support for their lightweight, conformal, and large-area manufacturing. The article further explores the technical connotation of “intelligent electromagnetic skin”, pointing out that its essence is not a single FSS structure, but a comprehensive control system integrating artificial electromagnetic units, adjustable devices, environmental perception, digital control, and algorithm decision-making, which is expected to promote the leap of electromagnetic surfaces from passive filtering to active perception and adaptive control.