标题： 超越对角异常散射体的物理极限和最优合成 显示英文标题

标题： Physical Limits and Optimal Synthesis of Beyond Diagonal Anomalous Scatterers

摘要： 实现用于异常散射的超表面对于设计反射器阵列、可重构智能表面和超表面天线至关重要。然而，引导散射进入非镜像方向的基本成本尚未完全理解。 本文利用配备非局部匹配网络的天线阵列系统，推导了异常散射的严格物理边界。这些边界是基于定义它们的优化问题的解显式综合出匹配网络的。 此外，我们分析了使用金属和介电材料实现的超表面天线的基本极限，在有限的设计区域内表现出最小损耗。 结果表明，在异常方向上的双站雷达散射截面（RCS）比前向方向减少了大约6dB。 数值实例补充了理论，并展示了在典型配置下，实现异常散射相对于前向或镜像散射的固有成本。 显示英文摘要

摘要： Realizing metasurfaces for anomalous scattering is fundamental to designing reflector arrays, reconfigurable intelligent surfaces, and metasurface antennas. However, the basic cost of steering scattering into non-specular directions is not fully understood. This paper derives tight physical bounds on anomalous scattering using antenna array systems equipped with non-local matching networks. The matching networks are explicitly synthesized based on the solutions of the optimization problems that define these bounds. Furthermore, we analyze fundamental limits for metasurface antennas implemented with metallic and dielectric materials exhibiting minimal loss within a finite design region. The results reveal a typical 6dB reduction in bistatic radar cross section (RCS) in anomalous directions compared to the forward direction. Numerical examples complement the theory and illustrate the inherent cost of achieving anomalous scattering relative to forward or specular scattering for canonical configurations.