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半导体多量子阱Mach-Zehnder调制器的性能分析 总被引:1,自引:0,他引:1
高速光调制器是高速光纤传输系统的关键器件之一 ,在各种类型的光波导调制器中 ,Mach- Zehnder干涉型调制器是最常用的调制器类型之一。概述了半导体多量子阱 Mach- Zehnder调制器的原理和性能 ,给出该类调制器的模型 ,最后介绍所获得的重要模拟结果。 相似文献
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全光纤的Mach—Zehnder干涉仪是一种重要的干涉器件。本文利用散射矩阵的分析方法,通过计算机数值模拟,研究了Mach—Zehnder干涉仪的传输特性,得出了输出端谱线与干涉仪结构参数的变化关系。 相似文献
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对全光纤双通Mach—Zehnder干涉仪滤波器进行了理论和实验研究,该干涉仪比常规Math—Zehnder干涉仪滤波器的峰值波长间隔周期小一倍,在实现密集波分复用光纤通信系统的扩大容量方面具有更大的优势。 相似文献
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文章分析了输入光偏振态对光纤Mach2Zehnder干涉仪条纹可见度和相位的影响,并通过实验进行验证。实验中,在干涉仪一干涉臂加入PZT相位调制器,通过示波器直接观测输入光偏振态对干涉仪输出光强波形的影响,并对输出波形变化进行了理论分析,验证了输入光偏振态对干涉仪可见度、相位的影响。 相似文献
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全光纤的Mach-Zehnder干涉仪是一种重要的干涉器件。本文利用散射矩阵的分析方法,通过计算机数值模拟,研究了Mach-Zehnder干涉仪的传输特性,得出了输出端谱线与干涉仪结构参数的变化关系。 相似文献
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本文对全光纤全息系统的原理、器件选择和实现手段进行了研究,采用光纤迈克耳逊干涉仪稳相结构建立了可应用于多种全息结构的全光纤全息系统,拍摄出了具有较为清晰再现象的全息图。本文结果证实了光纤全息系统在把全息技术用于现场实用方面的巨大潜力,为全息技术的进一步研究奠定了基础。 相似文献
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提出利用级联光纤环镜构成全光纤G -T干涉仪,并运用光波叠加原理和传输矩阵理论详细研究了其滤波和相位特性,给出了其相移表达式,分析了级联光纤环镜中各参数对其相位特性的影响。在此基础上,设计了一种基于级联光纤环镜G -T腔的新型全光纤交错复用器,该器件光学结构简单,具有DWDM系统所需的截止度和平坦度。 相似文献
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管道泄漏检测分布式光纤传感技术研究 总被引:29,自引:6,他引:23
提出了一种基于Mach—Zehnder光纤干涉仪原理的管道泄漏检测分布式光纤传感技术,该技术可以实时检测管道线发生的泄漏。分析了该技术的工作原理,讨论了在泄漏噪声作用下光纤中传播的光波相位变化关系。理论分析和测试结果表明,该测试技术可以有效地提高管道泄漏的测试灵敏度。在气体管道压力小于0.2MPa的条件下,可以检测到0.4m^3/min的气体管道泄漏,测试距离可达到50km。 相似文献
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An angular division multiplexer which uses graded-index (GRIN) rod lenses and a spatial modal filter (SMF) is described. Angular division multiplexing (ADM) uses selective excitation of mode groups " to multiplex signals in a transmission fiber. The GRIN-rod lenses collimate the input beams from two input fibers. The SMF selects particular mode groups from each input to be imaged on the transmission fiber. Design and construction of the device are described. Experimental results show that each signal is well confined to its designated mode groups. Crosstalk results are adequate for digital data transmission. 相似文献
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In this paper the realization and performance of a twodimensional finite impulse response (FIR) digital filter using adaptive delta modulation (ADM) have been studied. The analytical results have been verified by computer simulation. Also, it has been shown that onedimensional DM is adequate in the realization of a two-dimensional FIR ADM digital filter. Since the ADM digital filter requires no multiplication, it offers many advantages over conventional PCM filters in cost reduction, hardware simplicity, and reduced size. 相似文献
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《Solid-State Circuits, IEEE Journal of》1983,18(1):81-86
Employing an updated C/sup 2/MOS technique, two types of speech synthesizer LSI circuits, based on the PARCOR and the ADM methods, are introduced and described. These two LSI circuits fabricated with a standard metal gate CMOS process, have several features. 1) They can be operated with a single power supply over a 3-7 V range. 2) Their power dissipations are, respectively, 0.6 mW (PARCOR) and 0.18 mW (ADM) with the supply at 3 V. 3) High accuracy 9- and 10-bit R, 2R D/A converters are constructed in each LSI circuit. In the PARCOR system, various high quality and low data rate speech outputs are obtainable. The ADM system is used for voice transmission and synthesis. By adequately applying these two systems to the wide needs in the market, it is possible to achieve good cost performance. 相似文献
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Hill A.M. Brierley M. Percival R.M. Wyatt R. Pitcher D. Pati K.M.I. Hall I. Laude J.-P. 《Selected Areas in Communications, IEEE Journal on》1998,16(7):1134-1145
A wavelength division multiplexed (WDM) multiple-star network and its accompanying path and router protection strategies are proposed for interconnecting N major switch nodes in a national-scale telecommunications network. For a single path failure and uniform traffic matrix, fiber requirements are shown to be less than for a WDM ADM ring, while providing greater resilience to multiple path failures. “Adding” and “dropping” only whole wavelength channels between node pairs is found to lead to severe design instabilities and overinvestment in fiber, and time-sharing of wavelength channels is recommended to minimize fiber quantities. A star network capable of interconnecting N=22 switch nodes and an all-optical path protection switching method are verified experimentally, using a 16-channel 2,5-Gbit/s WDM system and a 22×22-port bulk-optics wavelength multiplexer as the hub router. Protection switching speeds within 50 ms are projected for a national-scale network 相似文献
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基于AWG二维编解码的OCDMA多用户分插复用 总被引:3,自引:3,他引:0
提出了一种新型的光码多分址(OCDMA)多用户分插复用器(ADM),所设计的ADM是基于阵列波导光栅(AWG)和二维时域/频域编码技术,可以从网络中同时取下多个码的数据而不影响剩余的码字信道,并且可以同时向网络中添加多个本地数据.设计的编解码器利用了Prime/OOC等具有特定规律的二维时域/频域扩展的码字,可以利用较少的AWG达到海量用户的编解码,系统集成度高.对所提出的ADM进行系统仿真,可以实现从4用户的网络中同时添加和取下2用户的功能,结果显示达到了所需的功能要求. 相似文献
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Delta Modulation (DM) is a simple waveform coding algorithm used mostly when timely data delivery is more important than the transmitted data quality. While the implementation of DM is fairly simple and inexpensive, it suffers from several limitations, such as slope overload and granular noise, which can be overcome using Adaptive Delta Modulation (ADM). This paper presents novel 2-digit ADM with six-level quantization using variable-length coding, for encoding the time-varying signals modelled by Laplacian distribution. Two variants of quantizer are employed, distortion-constrained quantizer which is optimally designed for minimal mean-squared error (MSE), and rate-constrained quantizer, which is suboptimal in the minimal MSE sense, but enables minimal loss in SQNR for the target bit rate. Experimental results using real speech signal are provided, indicating that the proposed configuration outperforms the baseline ADM algorithms, including Constant Factor Delta Modulation (CFDM), Continuously Variable Slope Delta Modulation (CVSDM), 2-digit and 2-bit ADM, and operates in a much wider dynamic range. 相似文献
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分插复用器(ADM)是组成同步数字传输网(SDH/SONET网)的基本单元,它可以同SDH的终端复用器(TM)、同步数字交叉连接设备(SDXC)及网络管理设备(TMN)等网络单元(NE)一起组成配置灵活的SDH传输网络。光群路单元板(OAU板)是ADM的核心部分。本文简要介绍ADM的功能组成与OAU板的参考设计。 相似文献
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A technique for digital conferencing of voice signals in systems using adaptive delta modulation (ADM) with an idle pattern of alternating 1's and 0's has been described. Based on majority logic, it permits distortion-free reception of voice of a single active subscriber by all the other subscribers in the conference. Distortion exists when more than one subscriber is active and the extent of this distortion depends upon the type of ADM algorithm that has been used. An LSI oriented system based on time sharing of a common circuit by a number of channels has been implemented and tested. This technique, with only minor changes in circuitry, handles ADM channels that have idle patterns different from alternating single 1's and 0's. 相似文献