Controlling the polarization state of electromagnetic waves is an important topic in microwaves due to the enormous application potential in radar technology and mobile communications. Here, we propose a programmable metasurface based on single-pole double-throw switches to realize multifunctional polarization conversions. A structure of the double-sided metallic pattern is adopted in the metasurface, in which a novel double-pole double-throw hub is achieved to guide the energy direction. Such a mechanism successfully induces multiple transmission channels into the metasurface structure for functional design. By controlling the states of the switches with a field programmable gate array, the x- and y-polarizations of the incident waves can be efficiently modulated into linear co- and cross-polarizations of transmitted waves, suggesting a higher degree of freedom on wave manipulations. The proposed metasurface can be developed as a near-field information encoder to transmit binary coding sequence according to the energy distribution. Character transmissions are realized by programming binary ASCII codes on the transmitted fields. Nine supercells on the metasurface can encode 9-bit binary information in one frame of near-field imaging, which can be switched in real time with high speed. We envision that this work will develop digital coding applications to control the polarization information.

中文翻译：

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用于近场信息编码和传输的双极化可编程超表面调制器

由于在雷达技术和移动通信中的巨大应用潜力，控制电磁波的极化状态是微波中的重要课题。在这里，我们提出了一种基于单刀双掷开关的可编程超表面，以实现多功能偏振转换。在超表面上采用双面金属图案的结构，其中实现了新颖的双极双掷轮毂以引导能量方向。这种机制成功地将多个传输通道引入超表面结构以进行功能设计。通过使用现场可编程门阵列控制开关的状态，x-和y入射波的极化可以有效地调制为传输波的线性共极化和交叉极化，这表明在波操作方面具有更高的自由度。所提出的超表面可以被发展为一种近场信息编码器，以根据能量分布来传输二进制编码序列。通过在传输的字段上编程二进制ASCII码来实现字符传输。超表面上的9个超级单元可以在一帧近场成像中对9位二进制信息进行编码，这些信息可以实时高速切换。我们预想这项工作将开发数字编码应用程序来控制极化信息。