In this article, a novel electrically controlled optical broadband phase shifter (ECO-BPS) is proposed and experimentally investigated for broadband microwave orbital angular momentum (OAM) mode generation. Based on the proposed ECO-BPS and a 17-element circular antenna array, the effect of the phase error on the OAM mode quality is studied by comparing the OAM modes respectively synthesized by three phase schemes: ideal phase shifts, ECO-BPS phase shifts, and optical true time delay phase shifts. In addition, the crosstalk caused by the phase error in applications of OAM modes multiplexing is investigated in a Dammann vortex grating based OAM modes demultiplexing system. All numerical simulation results demonstrate the feasibility of the ECO-BPS in broadband microwave OAM applications.

中文翻译：

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宽带微波轨道角动量模式的光学生成/检测

在本文中，提出了一种新型电控光学宽带移相器 (ECO-BPS)，并通过实验研究了宽带微波轨道角动量 (OAM) 模式生成。基于所提出的ECO-BPS和17单元圆形天线阵列，通过比较理想相移、ECO-BPS相移三种相位方案分别合成的OAM模式，研究了相位误差对OAM模式质量的影响，和光学真实时间延迟相移。此外，在基于Dammann涡旋光栅的OAM模式解复用系统中研究了OAM模式复用应用中相位误差引起的串扰。所有数值模拟结果都证明了 ECO-BPS 在宽带微波 OAM 应用中的可行性。