标题： 基于远场振幅的多模波导模态分析，采用大步长AdaMax方法 显示英文标题

标题： Modal Analysis of Multimode Waveguides Based on Large Step Size AdaMax from Far-Field Amplitudes

摘要： 优化多模波导性能依赖于模式分析；然而，当前方法主要关注模式功率分布，并且受限于实验硬件和条件，表现出低精度、适应性差和高计算成本。 在本工作中，在功率归一化约束下，我们采用具有大步长策略的AdaMax优化器，从远场振幅测量中进行多模波导的模式分析。 我们的方法同时恢复了模式功率分布和模式相对相位分布，并阐明了双图像模糊如何限制对模式相对相位分布的分析能力。 实验结果表明，所提出的方法在矩形和圆形波导中均表现良好，在信噪比（SNRs）范围为20到120 dB的噪声下保持高精度和鲁棒性，并且在精度和计算成本方面相比同类方法有显著提升。 该方法为模式分析提供了一种新的解决方案，具有广泛的应用潜力。 显示英文摘要

摘要： Optimizing multimode waveguide performance depends on modal analysis; however, current approaches focus predominantly on modal power distribution and, limited by experimental hardware and conditions, exhibit low accuracy, poor adaptability, and high computational cost. In this work, under a power-normalization constraint, we employ the AdaMax optimizer with a large-step-size strategy to perform modal analysis of multimode waveguides from far-field amplitude measurements. Our method retrieves both the modal power distribution and the modal relative-phase distribution, and we elucidate how twin-image ambiguity limits the capability to analyze modal relative-phase distributions. Experimental results demonstrate that the proposed method performs well for both rectangular and circular waveguides, maintaining high accuracy and robustness under noise with signal-to-noise ratios (SNRs) ranging from 20 to 120 dB, and achieving substantial improvements in accuracy and computational cost over comparable methods. This method provides a novel solution for modal analysis with broad application potential.