光开关矩阵在自动交换光网络中的应用

自动光交换网络是光网络的发展趋势,其核心技术是光开关矩阵。光开关矩阵是智能光交叉连接设备和可重构光分插复用器核心技术,是构建自动交换光网络的基础。主要介绍了大规模商用的光开关矩阵的技术特点及其在自动交换光网络中的应用。     

光开关矩阵技术及其性能分析

光开关矩阵是智能光交叉连接设备和可重构光分插复用器核心技术,是构建自动交换光网络的基础。本文主要介绍了大规模商用的光开关矩阵的关键技术原理,并且详细分析了由技术原理所决定的性能指标。     

光开关矩阵中Crossbar光交换网络的研究

针对DWDM光网络光交叉连接中光开关矩阵对其光交换网络的要求,分析了目前常用的置换型和常规型Crossbar光交换网络的性能,提出了一种新型的寻径型Crossbar光交换网络及其光学实现方法.该新方法利用1×2和2×1光开关构造寻径扇出和寻径扇入网络,具有严格无阻塞性,插损低,并可实现对光信号卸载,适用于中等规模的光开关矩阵.     

基于偏振的光矩阵开关

提出了一种新型的基于偏振的光矩阵开关方法 ,通过控制光的偏振态实现严格无阻塞连接。以 4× 4光矩阵开关为例 ,详细给出了其节点开关和交换网络的实现方案。并对该 4× 4光矩阵开关进行实测 ,证明该方法制作的小规模光矩阵开关具有插损低 ,串话小 ,开关时间中等 ,性能稳定 ,工艺成熟等特点。     

基于半导体光放大器的可扩展型光开关矩阵

未来的高速和高度灵活的光分组交换网络要求开关速度达到纳秒量级且集成度高的大规模空间光开关矩阵。在分析了基于半导体光放大器的常用结构形式的光开关矩阵存在规模局限性的基础上,综述了新型的可实现大规模集成的基于半导体光放大器的光开关矩阵的基本原理和研究现状。     

混洗网络中光开关矩阵研究

基于偏振控制技术,利用偏振光分束器和位相型空间光调制器构建1×2和2×1的节点开关单元,节点开关单元各端口间按照特定的映射规则和连接关系以光纤实现互连,从而得到一种新型的4×4光开关矩阵.该 4×4光开关矩阵利用位相型空间光调制器对信号光偏振态的控制实现路由,通过对其各输入端口光信号路由状态的分析表明,它可以完成信号光点对点的全排列无阻塞的输出与交换,同时,还具备部分的多点组播功能.该矩阵开关具有交换速度快、插入损耗小、串话低、性能稳定等特点,对于构建大规模的光互连网络具有一定的帮助.     

自动交换光网络中的节点技术

本文首先通过对几个典型产品的描述，回顾了自动交换光网络节点技术的发展，然后归纳出自动交换光网络节点的功能要求和属性，之后，从不同方面对光节点进行分类整理，并重点论述光交叉连接器的六种基本结构以及一种多颗粒度的通用结构，最后综述了所涉及到的光电子器件，尤其是微机电系统（MEMS）光开关。     

光交叉连接的硬件设计和应用

利用MEMS光开关来构建光交叉连接OXC目前成为一个研究热点。本文叙述了利用MEMS光开关构建光交叉连接的系统构架，提出了相应的硬件平台设计方案，并对实际的OXC交换板做了性能测试。从交换时间和插入损耗这两个指标来看，该OXC完全可以满足一般的交换速度和交换容量需求。同时，在实际制作的OXC交换板的基础上，通过加入扩展光器件，该OXC板可以扩展为带波长变换的光节点，可以实现ASON自动交换光网络的交换节点功能。     

光开关主流技术

光开关是光网络中完成全光交换的核心器件,它的研究日益成为全光通信领域关注的焦点.文章重点介绍了光开关在全光网络中的应用、MEMS光开关和热光开关的基本工作原理及两种光开关技术的进展,并就其他光开关作了简要介绍.     

高速光交换器件的控制和大电流驱动电路设计与实现

光突发交换(OptIcal Burst SwItching,OBS)技术吸收了光波长交换和光分组交换的优点,克服了二者的不足,有效降低了对光器件的要求.其关键技术之一是快速光交换矩阵,我们研究开发了多种能用于(OBS的光开关.本文针对这类光开关的驱动与控制技术开展研究.特别是对于高速、大电流的要求,研究如何在接收、处理以及输出控制等各环节尽量缩短时间,以提高开关速度.本文的研究成果也可用于其它具有高速、大电流要求的场合.     

光开关矩阵控制和驱动电路及集成技术的研究进展

文章简要介绍了光开关矩阵控制和驱动电路及集成技术的研究进展,重点分析了控制和驱动电路的功能以及不同类型和材料的光开关的控制和驱动电路的实现形式。同时讨论了控制和驱动电路与光开关芯片的系统集成方法。     

SS-TDMA switch matrices using optical technology

The principles and potential advantages of an optical switch matrix for use in an SS-TDMA microwave switching matrix subsystem are reviewed, and the relative merits of three optical switching techniques are compared. An INTELSAT sponsored programme is described that has demonstrated the feasibility and the problems of developing a compact, monolithic, optical switch matrix. RF performance generally exceeded that of switch matrices built using discrete microwave components. However, the switch matrix has a high insertion loss and requires temperature stabilization or compensation. To be practical, 1-3 micron of longer wavelength technology must be used.     

集成光开关阵列的研究进展

文中简要介绍了集成光开关阵列的研究进展,重点分析了不同材料和不同结构的开关 阵列的特点:绝缘体上的硅(SOI) 和III - V 族化合物半导体光开关阵列是阵列开关研究的重点,完全无阻塞简化树型和拜尼兹重排无阻塞型阵列开关有良好的综合性能,半导体光放大器(SOA) 光开关阵列已成为未来阵列开关发展的重要方向之一。     

Optical digital cross-connect system using photonic switch matricesand optical amplifiers

This paper presents, for potential application to network failure restoration, an optical digital cross-connect system (DCS) which uses both a photonic switching network and an electric DCS. It is shown that a system constructed of LiNbO₃ 8×8 switch matrices and semiconductor traveling-wave optical amplifiers (TWA's) could be applied to metropolitan area networks. An experimental optical DCS system has been designed and fabricated which incorporates both LiNbO₃ switch matrices and TWA's, and with it, line-failure restoration, a fundamental operation of optical DCS, has been successfully demonstrated     

Architectural design for multistage 2-D MEMS optical switches

Next-generation wavelength routing optical networks requiring optical cross connects (OXC) in the network have the ability to direct optical signals from any input interface to suitable output interfaces by configuring their internal embedded optical switch matrices. Microelectromechanical systems (MEMS) switches are regarded as the most promising technology to achieve such functionality. We consider the construction of a multistage MEMS switch network with single two-dimensional (2-D) MEMS switch blocks. A power loss model is developed that calls on a single MEMS block that is then used to develop the model for a three-stage Clos network. An effective model for maximum loss difference between calls is also developed. Based on these, the paper also proposes three connection patterns [Max + Min greedy (MMG), compressed extended generalized shuffle 1 (C-EGS-1), and compressed extended generalized shuffle 2 (C-EGS-2)] to connect outlet ports and inlet ports between two neighboring stages in a three-stage Clos network. These connection patterns are proved to be optimal and efficient enough to reach the minimums of both the maximum power loss of calls and the maximum loss difference between calls     

Large-capacity strictly nonblocking optical cross-connects based onmicroelectrooptomechanical systems (MEOMS) switch matrices: reliabilityperformance analysis

The reliability performance of 128× 128 optical cross-connects (OXCs) based on microelectrooptomechanical systems (MEOMS) switch matrices is considered. First, we compare a strictly nonblocking wavelength selective switch with a strictly nonblocking three-stage Clos architecture. The probability of maintenance of free operation has been investigated for both OXC structures. We present our calculation results for such commonly used reliability measures as mean time between failures (MTBF), mean downtime (MDT) per gear, and steady-state unavailability. It is shown that the reliability performances of the considered OXCs are far from that requested. In this paper, we also investigate possibilities of improving the reliability performance of the considered OXCs by introducing shared redundancy of the MEOMS matrices. We propose two different protection schemes: one for the wavelength selective switch and another for the three-stage Clos architecture. It is shown that the proposed protection schemes significantly improve the reliability performance for both cases. Finally, we compare the performance of the all-optical version of the OXC based on MEOMS matrices with the optoelectronic version of the OXC based on electronic cross-point switch matrices. It is shown that from a reliability viewpoint, the optical cross-connect based on MEOMS matrices is better than that with electrical cross-point switches. The influence of capacity expansion on the system reliability is discussed     

High speed, high capacity ATM optical switches for futuretelecommunication transport networks

This paper describes the work carried out in the RACE Project R2039 ATMOS (asynchronous transfer mode optical switching). The project is briefly illustrated, together with its main goal: to develop and assess concepts and technology suitable for optical fast packet switching. The project's technical approach consisted in the exploitation of the space and wavelength domains for fast routing and buffering: The major achievements are then reported. Four different switch architecture concepts have been proposed, investigated and developed, all based on a high speed optical routing matrix electrically controlled at lower speed. The basic optical key components and subsystems (wavelength converters, space switches and optical buffers) are described in detail, with the outstanding results obtained and the corresponding projected performance. In particular, system demonstration of wavelength conversion at 10 and 20 Gb/s has been realized, to show the usefulness of the ATMOS technology both to implement optimized high performance optical packet-switching fabrics as well as transparent optical circuit-routing nodes. Four rack-mounted, reduced size demonstrators of basic switching matrices have been designed and implemented scalable to real system sizes. The obtained good results in terms of bit error rate and hardware integration are reported, showing that ATM switches are feasible with state of-the-art optical technology     

Optical switch matrix with simplified N×Ntree structure

Optical switch matrices with compact size and excellent crosstalk characteristics are discussed. Novel architectures for optical switch matrices are obtained by condensing the structure of N× N tree structure. 4×4 switches fabricated on LiNbO₃ substrates are discussed     

宽带交换技术的演变与进展

本文简要分析了复用与交换技术的演变以及未来的光交换,分析了交换设备的构成及相关的网络控制与管理技术。阐述了作为IP与ATM融合的新一代网络交换技术－多协议标记交换（MPLS）,及其在光网络中的应用。进而分析了基于软交换技术的下一代网络结构,指出了业务、控制与交换将分离的趋势。最后指出,新型交换技术－MPLS和软交换将在网络演进过程中扮演极其重要的角色。