面向模分复用的少模光纤熔接失准容忍度分析方法  

Analysis Method of Misalignment Tolerance of Few-Mode Fiber Fusion Splicing for Mode Division Multiplexing

作　　者：刘峰[1] 黄自成 顾天乐 毛建龙 Liu Feng;Huang Zicheng;Gu Tianle;Mao Jianlong(College of Electrical and Electronic Engineering,Wenzhou University,Wenzhou 325035,Zhejiang,China)

机构地区：[1]温州大学电气与电子工程学院,浙江温州325035

出　　处：《光学学报》2024年第14期47-56,共10页Acta Optica Sinica

基　　金：国家自然科学基金(62105246);浙江省自然科学基金(LY23F050003)。

摘　　要：提出基于拉盖尔-高斯模的少模光纤熔接失准容忍度分析理论模型,剖析不同少模光纤归一化截止频率和纤芯半径参数熔接条件下,熔接点处空间模式耦合效率对横向偏移、旋转角度等熔接参数的容忍度变化规律,并以六模光纤(可支持LP_(01)、LP_(11a)、LP_(11b)、LP_(21a)、LP_(21b)和LP_(02)模式)熔接为例进行分析。数值分析结果表明,在不同光纤参数归一化截止频率V和纤芯半径a条件下,不同空间模式之间的耦合效率对熔接横向偏移量d和角度失配θ的容忍度呈现不同的分布规律。发送与接收少模光纤的V值相差越大,LP_(01)自耦合效率对熔接横向偏移量的容忍度越低,而不同纤芯半径a下熔接偏移量对自耦合效率的影响较光纤V的影响更显著等。因此,针对不同参数少模光纤熔接,需要严格控制熔接的横向偏移和角度失配,以达到理想的空间模式熔接耦合效率。该理论模型为评估少模光纤熔接质量及熔接参数匹配设计与优化提供了理论依据。Objective At present,few-mode fiber (FMF) communication technology,which is popular,is based on mode division multiplexing (MDM).The technology uses the new freedom of mode as an independent channel for information transmission.It can break through the capacity limit of traditional single-mode optical fiber communication and become the key to Tbit/s or even Pbit/s optical fiber communication.FMF fusion splicing is inevitable in the MDM system based on FMF.Therefore,the accurate analysis of the misalignment tolerance of FMF fusion splicing is of great significance for evaluating the fusion-splicing quality and optimizing the matching parameters of FMF,as well as ensuring the reliable and efficient operation of long-distance and large-capacity FMF links.At present,the tolerance of the coupling loss of the fundamental mode LP_(01) to the transverse offset,rotation angle,and fiber parameter misalignment are the main focus of a priori research.For the FMF that supports multiple spatial modes with coupling between spatial modes,the traditional single-mode fiber LP_(01) coupling loss theoretical is no longer suitable for analyzing coupling characteristics and misalignment tolerance of FMF fusion splicing.Given the current situation,it is of significance to study the tolerance characteristics of the high-order spatial mode coupling efficiency on the fusion splicing parameters of different transverse offsets and rotation angles under different parameters of FMF.Methods We propose a theoretical model based on the Laguerre?Gaussian mode to analyze the misalignment tolerance of FMF fusion splicing.Laguerre?Gaussian mode is utilized to approximate the LP_(mn) mode field distribution of each spatial mode.The coupling efficiency model between LP_(i) mode (transmitting FMF) and LP_(j) mode (receiving FMF) at the FMF fusion splicing is calculated by using the power transmission coefficient.The mathematical model can be estimated as a function of Gaussian waist radiusω,transverse migration d,and angle misalignment θ of the trans

关 键 词：光通信 模分复用 少模光纤 光纤熔接 耦合效率 容忍度 

分 类 号：O436[机械工程—光学工程]