基于波长选择开关的ROADM实现研究

可重构光分插复用(ROADM)设备可以通过软件实现远程节点上、下路和直通波长的配置.文章首先介绍了ROADM设备结构的演进过程,然后通过比较基于波长选择开关(WSS)的结构的ROADM设备,采用不同逻辑实现方式获得了不同特性,最后探讨了WSS的实现技术.     

ROADM全光交换网络关键技术发展与应用展望

介绍了可重构光分插复用器（reconfigurable optical add/drop multiplexer，ROADM）网络的发展历程、ROADM技术方案以及国内ROADM网络的部署情况。全面阐述了ROADM关键技术的发展方向，包括光交叉连接（optical cross-connect，OXC）设备、高维度波长选择开关（wavelength selected switch，WSS）、波长无关/方向无关/竞争无关ROADM （colorless/directionless/contentionless ROADM，CDC-ROADM）、400 Gbit/s FlexGrid ROADM、下一代波长交换光网络（next-generation wavelength switched optical network，WSON2.0）智能控制平面技术。分析了现有ROADM网络应用场景与技术发展趋势，展望了ROADM全光交换网络未来发展前景。     

ROADM技术及其实现的研究

随着ROADM技术的发展,运营商逐渐采用它作为传送网的重要光节点.文章分析了当前ROADM的三种主要技术(分别基于波长阻塞器、集成平面光波导和波长选择开关),讨论了实现ROADM的几个方案,提出一种称为Semi-ROADM的节点结构.它能在利用新技术的同时,降低成本、有效保护投资.     

广播与选择型ROADM的设计与实现

文章对动态可重构光分插复用器（ROADM）进行了介绍;对实现ROADM的多种方案进行了归纳整理和简要分析;对其中解复用／开关矩阵／复用（DSM）、DSM波段、广播与选择（B＆S）3种典型的ROADM结构进行了较详细的说明。文章作者设计并实现了广播与选择型ROADM,井对实验系统的上／下路功能和信道功率均衡功能进行了验证。     

GMPLS控制ROADM的光传送网结构和路由协议扩展

ROADM提供了光网络的灵活性和重配置能力,GMPLs是多层次交换网络统一的控制平面.在介绍ROADM技术和CMPLS协议的基础上,描述了由GMPLS控制ROADM构成的光网络结构,并完成扩展GMPLS路由协议以支持在ROADM端口约束条件下的路由.     

基于WB的ROADM实现及光通道OSNR代价分析

文章从业务发展的需求出发,详细讨论了可重构光分插复用器(ROADM)设备的优点,提出了一种基于波长阻塞器(Wavelength Blocker,WB)的ROADM实现方案,并针对实际应用测试了该ROADM节点设备的最大光信噪比(OSNR)代价.结果表明这种ROADM节点设备满足应用的需求.     

ROADM设备网管系统的实现

可重构的光分插复用(ROADM)设备是光传送网的重要节点,通过软件配置,可以灵活实现波长上下,使网络具备重构功能.建立基于SNMP协议的网元管理系统是保证ROADM设备稳定灵活工作的前提,文章简述了ROADM设备的功能结构,并讨论了设备网管系统的建立和配置功能的软件实现.     

ROADM技术简介及演进方向

阐述了可重构型光分插复用设备(ROADM)进入波分网络的背景,并对ROADM的3种主要技术进行了简要介绍。最后提出未来ROADM的发展方向,即ROADM光层调度 OTN电层调度组合解决方案,以及中兴通讯推出的适应市场发展的设备功能类型。     

Novel node upgradation strategy for migration to elastic optical networks

For migration from dense wavelength division multiplexing (DWDM) networks to elastic optical networks (EON),it is required to upgrade the traditional reconfigurable optical add-drop multiplexer (ROADM) to the new-generation ROADM that supports flexible grids.However,for a large-scale optical network,it is generally impossible to upgrade the ROADM nodes all in once; rather,they would be upgraded gradually.For this,it is critical to study different strategies for selecting the ROADM nodes to be upgraded.Also,for the interconnection between different generations of ROADM,the sub-band virtual concatenation (VCAT) technique was employed to enable an optical channel to be established via traversing different types of nodes.An integer liner programming (ILP) model and an efficient heuristic algorithm were developed to jointly select the ROADM nodes to upgraded and assign spectrum resources.Simulation studies show that the proposed strategy for the upgraded node selection is efficient to perform close to the ILP model in terms of the maximum number of FS used in the whole network.     

ROADM技术发展与标准化研究

本文研究了ROADM的技术优势，主要结构类型，涉及的关键技术以及存在的问题，并分析了当前ROADM标准化进展情况与发展趋势，还介绍了当前设备现状和现网应用情况。     

Digital optical networks using photonic integrated circuits (PICs) address the challenges of reconfigurable optical networks

To reduce costs and simplify operations, carriers are deploying flexible optical networks that can be easily reconfigured and managed remotely. This article provides an overview of typical all-optical reconfigurable optical add/drop multiplexer (ROADM) systems and their associated network issues. We describe a novel digital optical network architecture based on digital ROADM systems, which use photonic integrated circuits (PICs) to overcome many of these issues. Digital ROADM systems use monolithic PICs to integrate over 60 discrete optical components, including lasers, modulators and detectors, into a single pair of optical components, allowing cost-effective optical-electrical-optical conversion at every node. This also allows key functions such as service reconfiguration, add/drop and protection to be implemented in the digital domain, and enables de-coupling of service provisioning from optical link engineering, termed bandwidth virtualization. Finally, key deployment, reliability and operational metrics for PIC-based digital ROADM systems are presented.     

简化的ROADM模块及其在传送网络升级改造中的应用

首先介绍了现在流行的实现动态可重新配置光上下路复用器(ROADM)模块的解决方案,然后提出了一种简化的ROADM模块和网络结构,接着探讨了它在传送网络升级改造中可能的应用。该方案可用于提高新老设备的利用率,解决峰值时间和各站点间通信堵塞问题。文章还提出了一种用简化的ROADM实现环间业务动态调度的方法。文章所建议的ROADM模块具有成本低、对网络中其它信号干扰小等优点。     

可重构光分插复用器(ROADM)的技术实现与性能评估

从光网络节点的功能要求出发,详细讨论了开关型和调谐型两大类ROADM的技术实现方案,并对各种ROADM技术的性能进行了比较分析。     

Terabit Transmission at 42.7-Gb/s on 50-GHz Grid Using Hybrid RZ-DQPSK and NRZ-DBPSK Formats Over 16 × 80 km SSMF Spans and 4 Bandwidth-Managed ROADMs

We demonstrate for the first time the use of asymmetric-bandwidth interleaver-based reconfigurable optical add-drop multiplexer (ROADM) to transmit 42.7-Gb/s channels on a 50-GHz grid. Differential binary phase shift keyed (DBPSK) format was used on the wide passband side and differential quadrature phase shift keyed (DQPSK) format was used on the narrow passband side of the ROADM. 25 channels with an aggregate capacity of 1-Tb/s were transported over 1280-km of standard single-mode fiber (SSMF) including 4 ROADMs.     

面向超100G系统的可变带宽ROADM及控制平面技术

研究了基于ROADM和灵活栅格技术的结合实现超100G光线路上的灵活封装和智能调度的解决方案。重点分析了如何通过控制平面的不同模块来实现更加高效支持灵活栅格的ROADM与整个超100G系统的协同统一工作,打造新一代智能弹性高速光网络的架构。     

Mathematical formulation of provisioning of connections with advance reservation in metro WDM ring networks using reconfigurable OADMs (ROADMs) with tuning constraint

Optical add/drop multiplexers (OADMs) can significantly reduce the cost of metro optical wavelength-division multiplexing (WDM) ring networks by allowing traffic to bypass intermediate nodes without expensive opto-electro-opto (O-E-O) conversion. Some traditional OADMs, called fixed OADMs (FOADMs), can only add/drop traffic on a specific wavelength. Reconfigurable Optical Add/Drop Multiplexers (ROADMs) are emerging, which can add/drop traffic onto/from different wavelengths at different time. ROADMs provide desirable flexibility, enable fast provisioning of dynamic traffic, and save capital expenditure (CapEx) and operational expenditure (OpEx). In order to be cost-effective, some ROADMs employ architectures that tune the ROADM continuously from one wavelength to another, crossing through all the wavelengths in-between, which may cause interference to the connections, if any, on those wavelengths being crossed. In order to prevent existing connections from being interrupted, a constraint needs to be imposed that ROADMs cannot cross working wavelengths when tuning. In this study, the design and the benefits of metro optical WDM network architectures using ROADMs and the impact of this tuning constraint on the performance of the network are investigated. Mathematical formulation of the problem of provisioning of connections with advance reservation, in which the arrival time and departure time of all the connections are known in advance, is presented, and results for a small network are shown.     

Reconfigurable Optical Add‐Drop Multiplexer Using a Polymer Integrated Photonic Lightwave Circuit

We have developed a fully functional reconfigurable optical add‐drop multiplexer (ROADM) switch module using a polymer integrated photonic lightwave circuit technology. The polymer variable optical attenuator (VOA) array and digital optical switch array are integrated into one polymer PLC chip and packaged to form a 10‐channel VOA integrated optical switch module. Four of these optical switch modules are used in the ROADM switch module to execute 40‐channel switching and power equalization. As a wavelength division multiplexer (WDM) filter device, two C‐band 40‐channel athermal arrayed waveguide grating WDMs are used in the ROADM module. Optical power monitoring of each channel is carried out using a 5% tap PD. A controller and firmware having the functions of a 40‐channel switch and VOA control, optical power monitoring, as well as TEC temperature control, and data communication interfaces are also developed in this study.     

Parallel-stage-based reconfigurable optical add-drop multiplexer for WDM optical transport networks

This letter proposes a simple and flexible reconfigurable optical add-drop multiplexer (ROADM) based on parallel-stage configuration using Mach-Zehnder-based fiber gratings, 1/spl times/2 optical switches, and Y-model combiners. The proposed ROADM with four-stage parallel configuration is designed and experimentally investigated to show its performance in full wavelength selection and advantages in reducing the discrepancy of the insertion loss between channels and upgrading.     

可重构型光分插复用器浅析

随着可重构型光分插复用器(ROADM)在过去几年的发展,完全的光交换成为可能,使得动态光网络逐渐取代了传统的静态光网络,在通信和网络领域占据了重要的地位。这里首先介绍了ROADM架构,然后阐述了目前ROADM中最为关键的波长选择交换器的实现原理以及4种不同的可用的解决方案,并对他们的优点和缺点进行了分析。最后对未来可能的应用和发展方向进行了讨论。     

ROADM网络在香港区域的应用

基于波长选择开关和密集波分技术（DWDM）的ROADM网络,在网络扩容、灵活配置、快速保护恢复等方面有较强优势;同时,还可大幅降低网络投资,减少机房空间占用和电力消耗。香港区域ROADM网络的建成,所具备的业务灵活调度能力和快速恢复能力,将大大提升对业务需求的快速响应。香港区域ROADM网络将使中国电信国际公司具有更强的竞争力。