Dynamic metasurface antennas (DMAs) are a promising embodiment of next-generation reconfigurable antenna technology to realize base stations and access points with reduced cost and power consumption. A DMA is a thin structure patterned on its front with reconfigurable radiating metamaterial elements (meta-atoms) that are excited by waveguides or cavities. Mutual coupling between the meta-atoms can result in a strongly non-linear dependence of the DMA's radiation pattern on the configuration of its meta-atoms. However, besides the obvious algorithmic challenges of working with physics-compliant DMA models, it remains unclear how mutual coupling in DMAs influences the ability to achieve a desired wireless functionality. In this paper, we provide theoretical, numerical and experimental evidence that strong mutual coupling in DMAs increases the radiation pattern sensitivity to the DMA configuration and thereby boosts the available control over the radiation pattern, improving the ability to tailor the radiation pattern to the requirements of a desired wireless functionality. Counterintuitively, we hence encourage next-generation DMA implementations to enhance (rather than suppress) mutual coupling, in combination with suitable physics-compliant modeling and optimization. We expect the unveiled mechanism by which mutual coupling boosts the radiation pattern control to also apply to other reconfigurable antenna systems based on tunable lumped elements.

翻译：动态超表面天线（DMA）是实现低成本、低功耗基站与接入点的下一代可重构天线技术的重要实现形式。DMA是一种薄层结构，其表面刻有由波导或空腔激励的可重构辐射超材料单元（元原子）。元原子间的互耦效应会导致DMA辐射方向图对其元原子配置产生强烈的非线性依赖关系。然而，除了基于物理合规DMA模型所面临的算法挑战外，DMA中的互耦效应如何影响实现预期无线功能的能力仍不明确。本文通过理论分析、数值模拟与实验验证表明：DMA中的强互耦效应可提升辐射方向图对天线配置的敏感度，从而增强对辐射方向图的调控能力，改善辐射方向图与目标无线功能需求的匹配程度。与直觉相悖的是，我们建议在结合物理合规建模与优化方法的基础上，下一代DMA设计应增强（而非抑制）互耦效应。我们揭示的互耦增强辐射方向图调控机制，预计同样适用于基于可调集总元件的其他可重构天线系统。