Beam-Editing Coding Metasurfaces Based on Polarization Bit and Orbital-Angular-Momentum-Mode Bit
Beam-Editing Coding Metasurfaces Based on Polarization Bit and Orbital-Angular-Momentum-Mode Bit
复制标题
基于偏振位和轨道角动量模式位的光束编辑超表面
DOI：
10.1002/adom.201700548
复制
发表时间：
2017-12-01
影响因子：
9
通讯作者：
Cui, Tie Jun
中科院分区：
文献类型：
--
作者：
Ma, Qian;Shi, Chuan Bo;Cui, Tie Jun
编码元表面旨在表示元表面的数字信息，通常通过编程数字单位单元来控制电磁波。然而，由于通常相位码的非正交性，有些信息序列不能被接收机识别。本文提出了一种新的编码方法，利用发射光束中的正交参数对信息进行编码，减少了系统中的信息丢失。提出了一种结合正交偏振和轨道角动量（OAM）模式的矢量光束调制器。正交入射波可以通过OAM模式比特和偏振比特进行调制，接收机将其视为特定信息。偏振转换器用于独立地实现偏振选择（偏振位）和相位控制。编码元表面上的相位图案可以被编程以在微波频率中实现所设计的OAM模式（OAM比特）。提出了三种方案来发射双偏振中的多个OAM模式，其中一种是针对近场和远场制造和测量的。仿真和实验结果吻合良好，验证了所提出方案的优良性能。这项工作在编码元表面的通信应用中具有很大的潜力。
Coding metasurfaces are aimed at representing digital information of the metasurface, usually by programing digital unit cells to control electromagnetic waves. However, some information sequences cannot be recognized by the receiver, because of nonorthogonality of the usual phase codes. Here, new coding method is proposed to encode information with orthogonal parameters in the emitting beam, which reduces information loss in the system. A vector beam modulator is proposed by combining orthogonal polarizations and orbital angular momentum (OAM) modes. A normal incident wave can be modulated by OAM-mode bit and polarization bit, which are regarded as specific information by the receiver. A polarization converter is used to realize the polarization selection (polarization bit) and phase control, independently. The phase patterns on the coding metasurfaces can be programed to realize the designed OAM modes (OAM bits) in the microwave frequency. Three schemes are presented to emit multiple OAM modes in dual polarizations, one of which is manufactured and measured for near and far fields. The simulations and experiments are in outstanding agreement, verifying the excellent performance of the proposed schemes. This work has great potential in communication applications of coding metasurfaces.