集成可调谐滤波器的光开关器件技术研究

Research on Technology of Optical Switch Devices with Integrated Tunable Filters

【目的】在可重构光分插复用器(ROADM)下行传输中,可调谐光滤波器(TOF)是在一定光带宽范围内动态选择波长通过的滤波器,通过对波长选择开关(WSS)或多播切换开关(MCS)输出端口进行波长选择滤波筛选并对光强进行衰减均衡,使得ROADM各个输出端口光强一致。MCS基于光开关(OSW)原理,通过同时切换多个输入通道将数据传输到一个或多个输出端口,对多播数据实现快速、准确和可靠地传输。当前大多数MCS需要与TOF阵列一同工作,以避免意外信道,同时确保在MCS之后进入接收器的功率不会饱和或严重串扰。目前大多数TOF阵列尺寸较大,很难与MCS集成,影响了无色无方向性无竞争性(CDC)-ROADM的实现。为了降低ROADM下行传输系统的实现难度,需要解决模块体积臃肿的问题。因此,文章设计了一种集成TOF功能的OSW器件,减小了MCS模块的体积并优化了结构。【方法】文章将TOF的功能集成到MCS模块中,设计了同时能实现光通道选择和光波长选择功能的器件。由于微机电系统(MEMS)可以分别实现OSW和TOF的功能,且MEMS器件相对容易实现,兼具调谐速度快、可调谐范围宽和体积小等优点,因此文章基于现有MEMS OSW和TOF方案设计了一种兼具二者功能的新器件。该器件基于MEMS技术,配以多芯准直器,使得器件的X和Y轴分别实现OSW和TOF功能,且功能间互相独立,干扰较小。文章介绍了此器件的基本原理和光学结构,并在此基础上进行了光学设计和仿真验证。【结果】仿真结果表明,该器件具有良好的光学性能,可以满足MCS器件的使用需求。【结论】文章所提采用TOF-OSW器件的MCS模块相当于在其中集成了TOF的功能,因此省去了原本TOF的成本和空间,降低了成本并减少了占用空间及降低了系统复杂度,因此TOF-OSW器件有着广阔的应用前景及实际需求,也能更好地满足ROADM系统对实现CDC功能的需求。

【Objective】In Reconfigurable Optical Add Drop Multiplexer(ROADM)downstream transmission,Tunable Optical Filters(TOF)are used to dynamically select wavelengths within a certain optical bandwidth range.By performing wavelength selection filtering and optical intensity attenuation equalization at the output ports of Wavelength Selective Switches(WSS)or Multicast Switches(MCS),the optical intensity at each output port of the ROADM is made consistent.MCS operates based on the Optical Switch(OSW)principle,enabling fast,accurate,and reliable transmission of multicast data by simultaneously switching multiple input channels to one or more output ports.Currently,most MCSs need to work in conjunction with TOF arrays to avoid accidental channels and ensure that the power entering the receiver after the MCS does not saturate or experience severe crosstalk.Most current TOF arrays are large,making integration with MCS difficult,thus affecting the realization of Colorless,Directionless and Contentionless(CDC)-ROADM.To reduce the implementation complexity of the ROADM downstream transmission system,it is necessary to address the issue of bulky module sizes.Therefore,this article designs an OSW device integrated with TOF functionality to reduce the size of the MCS module and optimize its structure.【Methods】The article integrates TOF functionality into the MCS module and designs a device that can achieve both optical channel selection and optical wavelength selection functions simultaneously.It is noted that Micro Electro Mechanical Systems(MEMS)can respectively realize the functions of OSW and TOF,and MEMS devices are relatively easy to implement with advantages such as fast tuning speed,wide tunable range,and small size.The article designs a new device combining both functions based on existing MEMS OSW and TOF solutions.This device is based on MEMS technology and is equipped with a multi-fiber collimator,enabling the X and Y axes of the device to respectively realize OSW and TOF functions with minimal mutual interference.The article introduces the basic principles and optical structure of this device and conducts optical design and simulation verification.【Results】Simulation results show that the device has good optical performance and can meet the usage requirements of MCS devices.【Conclusion】The MCS module using the TOF-OSW device proposed in the article integrates the TOF function,thereby saving the cost and space of the original TOF,reducing costs,space occupation,and system complexity.Therefore,the TOF-OSW device has broad application prospects and practical demand,better meeting the ROADM system's need for implementing CDC functionality.