G.652光纤上的2.5Gbit／s色散受限系统

本文根据色散受限中继段长度的计算，对实际工程中１５５０ｎｍ波长２．５Ｇｂｉｔ／ｓ系统进行计算比较得出啁啾声引起的色散不容忽视，它使２．５Ｇｂｉｔ／ｓ成为色散受限系统。对１３１０ｎｍ波长６２２Ｍｂｉｔ／ｓ系统，当使用多纵模激光器时，往往也会成为色散受限系统。     

Analysis method of the effect of fabrication errors on a planar waveguide demultiplexer

The impact of fabrication errors on a planar waveguide demultiplexer is analyzed based on an analytical method. The explicit expression of the transfer function taking into account phase and amplitude errors is presented in order to analyze the loss and crosstalk of the demultiplexer caused by fabrication errors. A basic requirement for the demultiplexer with a certain crosstalk criterion can be easily obtained. Using an etched diffraction grating demultiplexer as an example, it is shown that the analytical results have a good agreement with results from a numerical method.     

G.652光纤长途传输系统的色散补偿

针对当前国内长途传输光缆系统在扩容过程中，因光信号色散而影响传输质量的现象，结合实际工程建设，分析了光信号色散的危害及其成因，并提出了相应的解决办法及建议。     

无线传感器网络MAC层协议的对比研究

无线传感器网络是二十一世纪新兴的网络技术，它的出现使网络的发展进入一个新的阶段。针对无线传感器网络MAC层协议的研究一直是人们普遍关注的问题。总结了近年来的研究成果并针对TDMA，IEEE802．15．4，S—MAC，T—MAC几种典型的MAC层协议进行了对比分析，根据其各自的优点提出将来工作的方向和建议。     

Transmission Fiber Chromatic Dispersion Dependence on Temperature: Implications on 40 Gb/s Performance

In this letter, we will evaluate the performance degradation of a 40 km high‐speed (40 Gb/s) optical system, induced by optical fiber variations of the chromatic dispersion induced by temperature changes. The chromatic dispersion temperature sensitivity will be estimated based on the signal quality parameters.     

Performance evaluation of fiber Bragg grating sensors by digital holographic technique, strain gauge measurement

In view of the growing interest for non-destructive tests of materials, geodynamical monitoring and in general remote sensing, there is a great effort to bring practical optical sensors from research labs to industrial and environmental applications. In this paper, we employ digital holographic technique as an efficient tool for evaluating the strain measurement capability of fiber Bragg gratings (FBG). A cantilever beam has been employed as a test structure under loading test. The strain measurements results obtained by fiber-based sensors have been compared to those obtained by using full-field digital holographic technique and point-wise strain gauge sensors glued on the same cantilever beam. A simple theoretical model is also presented to interpret and compare the experimental results coming from different techniques.     

高折射率芯Bragg光纤的色散特性研究

应用超格子模型分析了高折射率芯Bragg光纤的色散特性，讨论了Bragg光纤的色散的比例性质以及光纤的芯径、包层周期、填充率与波导色散的关系，并利用这些关系举例实现了Bragg光纤在1.55μm附近的宽带色散平坦. 关键词： Bragg光纤 模式 色散 波导色散     

Advanced modulation formats for more robust optical transmission systems

Interest in advanced modulation formats for optical communication systems has so far experienced two major waves. The first one was motivated by the potential to enhance receiver sensitivity of thermal noise-limited systems using coherent detection in combination with phase shift keying. It ended with the advent of optical amplification, enabling high sensitivities together with polarization insensitive, simple and stable direct detection. The second wave is still rolling, fueled by the potential of advanced modulation formats to increase robustness of optical transmission systems against signal distortions. Due to performance limitations given by direct detection and nonlinear effects in the transmission fiber, it is not decided yet, whether there will be widespread application in carrier networks.     

光波分复用技术及其应用

分析了波分复用系统的组成原理和几种分类方式,最后给出了一些基本应用形式。     

可见光共振腔发光二极管的研究进展

共振腔发光二极管是一种具有优良发光性能的光电器件。概述了对可见光共振腔发光二极管的共振腔结构、反射镜材料体系、基本工作机理和发光特性，并展望了这种器件的发展前景。