一种DWDM光源混合式控制器设计

分析了数字控制器和模拟控制器在DWDM(密集波分复用)光源控制器设计中的优缺点,提出了一种混合式控制器的设计.该控制器的核心是模拟控制器,能够较好地保证系统的稳态精度.同时利用数字控制器对其进行监控,调整控制参数,保证DWDM光源的长期工作稳定.实验研究表明,该系统工作波长稳定性在0.005 nm以内,而且能够对系统参数漂移进行自校正.     

基于固体腔F-P 标准具的可调谐自适应光滤波器

对F—P干涉滤波器的原理特性进行了分析。提出了通过改变入射角度来实现波长调谐的可调谐滤波器结构。采用了一种新的降低斜入射F—P标准具偏振相关损耗的结构。采用位置敏感探测器成功实现了关键约定位工作。采用了一种简单易行的波长跟踪方案。本系统实现了32通道0．8nm间隔DWDM系统精确滤波。     

一种50GHz信道间隔光通道监测仪的研究

为实现50GHz信道间隔的密集波分复用(DWDM)系统中的光通道性能监测,文章提出一种基于衍射光栅的OCM(光通道监测仪)结构,介绍了该OCM的工作原理。从理论上对其工作范围、响应时间、波长分辨率和通道分辨能力进行了计算和分析,并制作了样品进行实验测试。结果表明,对于传输速率为10Gbit/s/40Gbit/s混合传输的50GHz信道间隔的DWDM系统,该OCM可以对波长、功率性能进行准确监测。     

光纤智能结构中Bragg光栅的DWDM检测

光纤Bragg光栅传感器以其优越的性能是最有希望应用于光纤智能结构中的传感器。基于DWDM原理与技术提出了在光纤智能结构的应用中检测光栅波长位移的DWDM方法，进行了实验研究和相关讨论，实验表明在较大范围内波长位移与轴向应变呈线性．为光纤光栅智能结构的实用化推广打下基础．     

光纤光栅传感应用中波长位移量检测的DWDM方法

基于光纤通信系统中 DWDM原理与技术 ,提出了一种在光纤光栅传感系统中检测光栅波长偏移量的 DWDM方法 ,这是一种测量波长偏移量的新方法。给出了光栅 Bragg波长偏移量 ΔλB与轴向应变 εz和环境温度变化量 ΔT之间的相互关系曲线 ,也给出了 DWDM波长间隔 Δλ与轴向应变 εz和温度变化 ΔT分辨率之间的相互关系曲线 ,并进行了相关讨论     

DWDM系统中OTU中继功能的应用

对DWDM系统中OTU的中继功能做了简要阐述，将利用OTU中继功能进行光纤直连方案与采用点对点DWDM设备组网方案进行了比较，并结合漳州本地网DWDM扩波和优化工程说明其实际应用。     

采用SOA的以太网媒体转换器的设计与实现

双绞线/光纤媒体转换器可以大大扩大LAN的直径，解决LAN设备之间不同接口互相匹配问题，实现以太网信号在不同传输介质之间的转换，文章介绍了一种10Base-T双绞线/光纤媒体转换器的工作原理，设计与实现，由于光源选用SOA，故此媒体转换器的波长符合DWDM系统需求并且波长可调，最后还给出了实验结果和结论。     

稀疏波分复用与密集波分复用的比较

稀疏波分复用（CWDM）系统的作用与WDM相同。如今部分厂商已经能够提供具有2到8个波长的商用CWDM系统，将来这些系统有望在1290nm到1610nm的频谱内扩展到16个复用波长。目前，大多数CWDM系统工作在从778nm到850nm和1470nm到1610nm的范围内，其信道间距为20nm，并可以利用大量的旧光纤（G.652光纤），节省了投资成本。硬件CWDM系统不包含线路放大器。由于器件成本和系统要求的降低，使得CWDM系统的造价比DWDM系统大幅下降。DWDM的收发设备要比CWDM系统的同类产品贵四、五倍，这与激光器的许多因素相关。CWDM的激光器与DWDM…     

DWDM传输用的新型光源组件

一种应用于DWDM传输的新型光源组件正在被开发。这种光源组件由半导体光放大器(SOA)、光纤布拉格光栅和致冷器构成。这种光源组件的最大优点是具有极其稳定的波长稳定性和更小的啁啾。其他性能均与常规DFB-LD一样好。因此成为一种较为理想的DWDM光源。利用已成熟的SOA和光纤光栅，便可组装出这种光源。从已发表资料表明，该光源组件可望在未来取代现行DWDM传输系统中的常规DFB-LD。     

DWDM光纤通信网络中光发射单元的智能化监控

实现了密集波分复用 (DWDM)光纤通信网络中光发射单元 (OTU)的智能化监控 ,设计了以80 C5 5 2单片微机为核心的盘控 (MCU)部分 ,实现了激光器输出波长、光功率、偏置电流等重要参数的随时监控 ,并能在激光器工作状态异常时 ,及时上报网管、控制告警灯并自动调节激光器 ,以保证通信系统的顺利进行。成功地完成了 16× 10 Gb/ s的系统实验 ,各波长信道的传输功率代价均小于 2 d B(误码率 =10 - 1 0 )     

Configuration of more than N DWDM channels with only one N × N cyclic-AWG-based wavelength routing device

A wavelength routing device based on only one N × N cyclic arrayed waveguide grating (AWG) having easy extended channels configuration is presented in this paper. It is easy to extend the dense wavelength division multiplexing (DWDM) channel configuration through this wavelength routing device. According to the cyclic wavelength of AWG, the wavelength routing devices are easy to configure more than N extended DWDM channels through cascading more proper tunable fiber Bragg gratings (FBGs). With only one 8 × 8 AWG, two different wavelength routing structures were built to evaluate static crosstalk and the bit-error-rate (BER). Three of the 16 inputted DWDM channels were demonstrated to verify that the proposed wavelength routing device, with only one 8 × 8 AWG, could configure extended DWDM channels without interfering with other channels. The results show that the wavelength routing device can produces a better performance and offers a cheaper way to extend the DWDM channel configuration for a dynamic network.     

DWDM系统中的前向纠错级联码

本文通过对DWDM光通信系统的发展趋势和级联码的理论进行分析后,对DWDM系统中现有的前向纠错(FEC)编码技术提出了内外型、并行型和连续型的三种级联码改进方案.通过理论分析与仿真结果表明:内外型级联码冗余度过大,并行型级联码的译码实现过于复杂,而连续型级联码是一种纠错性能优良,冗余度适中、易于实现的码型,更适用于高速DWDM系统.     

Forward error correction concatenated code in DWDM systems

The three concatenated coding schemes of the inner-outer type, the parallel type and the consecutive type to improve the current forward error correction (FEC)coding technologies are proposed for dense wavelengthdivision multiplexing (DWDM) systems, after introducing the development trend of DWDM optical communication systems. The concatenated code is theoretically analyzed.The theoretical analyses and simulation results show that inner-outer concatenated code has a greater redundancy and the decoding of parallel concatenated code is too complex. However, consecutive concatenated code is superior coding scheme with advantages such as better error correction performance, moderate redundancy and easy implementation, therefore it could be better used in high-speed and long-haul DWDM systems.     

Efficient Transmission Scheme for AWG-Based DWDM Millimeter-Wave Fiber-Radio Systems

We propose and demonstrate an upstream transmission scheme using a semiconductor optical amplifier (SOA) for arrayed waveguide grating (AWG)-based dense wavelength-division-multiplexed (DWDM) millimeter-wave fiber-radio systems and show improved link performance. In our scheme, unused optical carriers from the cyclic AWG in the downlink (DL) are tapped for uplink (UL) transmission. An SOA in conjunction with the AWG simultaneously amplifies the DL RF subcarriers and UL optical carrier, thus improving carrier-to-sideband ratio in the DL while also yielding an improved power budget for the UL. Our experimental results show that the proposed scheme can be a practical solution for future bidirectional wavelength interleaved DWDM transmission systems     

DWDM系统中波长变换技术的实现

提出一种光电光波长变换的方法 ,对其设计和性能进行了介绍。该波长变换器满足 DWDM系统对波长稳定性的要求 ,并已成功地应用于已研制的波长间隔为 1 6nm的 WDM系统中。     

光通信用DWDM器件的制作工艺及其参数测试

密集波分复用(DWDM)是光纤通信增容的首选方案,而波分复用/解复用器件(DWDM器件)是DWDM系统中的关键器件。本文讨论了DWDM器件的几种典型制作方法,其中薄膜滤光片(TFF)型器件是最富竞争力的,并对TFF 型DWDM器件的制作工艺、主要特性参数及其测试方法开展了实验研究,对我们自行研制的四通道TFF型DWDM器件的测试结果表明:该器件具有精确的中心波长、宽且平坦的带通、小而均匀的插入损耗以及较大的信道隔离度等特性,具有很好的应用前景。     

DWDM系统的在线光谱监测

通过对 DWDM合路光信号性能指标的特点与在线监测必要性的分析 ,提出了利用可调谐 F- P干涉滤波器进行光谱监测的技术 .通过实验 ,取得了较好的结果实验数据 ,并实现了 32× 2 .5Gbit/s DWDM系统中的在线光谱监测     

可调谐激光器技术及其在DWDM系统的应用

大容量、长距离DWDM传输系统及动态波长交换DWDM光网络对保护方式、波长分配、波长备份成本的要求,使可调谐激光器变得十分重要。讨论了常用可调谐激光器的技术原理和水平,概要说明了可调谐激光器的市场前景,介绍了可调谐激光器在DWDM系统中的部分应用。     

Multichannel single-sideband SCM/DWDM transmission systems

To understand the transmission limitation of multiple narrow single-sideband subcarrier-multiplexed (SSB/SCM) signals, this paper first presents a closed-form analysis to predict Mach-Zehnder intensity modulator-induced composite triple beat (CTB), and linear-fiber-dispersion-induced composite second-order (CSO) and CTB distortions. To combine SSB/SCM with dense-wavelength-division-multiplexing (DWDM) systems, analytical and numerical tools, which are not constrained by any wavelength spacing and modulation frequencies, are used to analyze cross-phase modulation-induced crosstalk. All the analytical and numerical results are verified by computer simulations. Several multichannel SSB/SCM/DWDM systems with transport capacities of 10 or 20 Gb/s per wavelength, with a wavelength spacing of 25, 50, and 100 GHz, are also studied in this paper to understand the fundamental transmission limitations.     

Crosstalk Analysis of a Fiber Laser Sensor Array System Based on Digital Phase-Generated Carrier Scheme

A detailed study on analyzing the crosstalk in a wavelength division multiplexed fiber laser sensor array system based on a digital phase generated carrier interferometric interrogation scheme is reported. The crosstalk effects induced by the limited optical channel isolation of a dense wavelength division demultiplexer (DWDM) are presented, and the necessary channel isolation to keep the crosstalk negligible to the output signal was calculated via Bessel function expansion and demonstrated by a two serial fiber laser sensors system. Finally, a three-element fiber laser sensor array system with a 50-dB channel-isolation DWDM was built up. Experimental results demonstrated that there was no measurable crosstalk between the output channels.