This paper investigates the performance of generated delays from an orbital angular momentum mode shifting recirculating delay loop (OAM-SL) in simulation using Kirchhoff-Fresnel diffraction (KFD) and the delays applicability for RF signal beam steering applications. OAM-SL is a novel structure that has been recently reported to produce multiple delayed signal replicas on independent OAM carriers using a single compact system. The objective of this research is to explore the impact of several limiting factors on the quality of OAM-SL delays for beam steering applications, such as where there is (i) displacement of the OAM mode shifter, (ii) displacement of the center of the OAM mode demultiplexer at the loop output, and (iii) the limited resolution. The methodology includes: (i) simulating the beam propagation using KFD, (ii) producing the output as a coherent summation of the recirculating beams, and (iii) characterizing the SCR by dividing the power of the recirculating beam () on its OAM mode by the power accumulated from the other recirculating beams. Our findings show that delays generated from a system with , , and a resolution of 1024 pixels can steer a 100 MHz signal at a steering angle of in a four antenna system with error if loop alignment is perfect. Also, for steering the 100 MHz signal in an eight antenna system, we analyze the system assuming the system loss can be compensated, and a similar result of error is obtained. Additionally, we report the beam steering performance at and .

中文翻译：

---

使用光学 OAM 模移循环环路生成的延迟进行波束控制

本文研究了使用基尔霍夫-菲涅耳衍射 (KFD) 进行仿真时轨道角动量模移循环延迟环 (OAM-SL) 生成的延迟的性能以及延迟对射频信号波束控制应用的适用性。 OAM-SL 是一种新颖的结构，最近有报道称，它可以使用单个紧凑系统在独立的 OAM 载波上产生多个延迟信号副本。本研究的目的是探讨几个限制因素对波束控制应用中 OAM-SL 延迟质量的影响，例如存在 (i) OAM 模式转换器的位移、(ii) 中心位移的情况。环路输出处的 OAM 模式解复用器，以及 (iii) 有限的分辨率。该方法包括：(i) 使用 KFD 模拟光束传播，(ii) 产生作为循环光束的相干总和的输出，以及 (iii) 通过除以循环光束 () 的 OAM 模式功率来表征 SCR由其他循环光束累积的功率。我们的研究结果表明，如果环路对准完美，则分辨率为 1024 像素的系统产生的延迟可以在四天线系统中以 100 MHz 的转向角引导 100 MHz 信号，但会出现错误。此外，为了在八天线系统中控制 100 MHz 信号，我们分析了系统，假设系统损耗可以得到补偿，并获得了类似的误差结果。此外，我们还报告了 和 处的波束转向性能。