WDM光传输系统2.5Gbit／s光发送模块研究

本文介绍了作者设计，调试的２．５Ｇｂｉｔ／ｓ光发送模块的工作原理、关键技术、典型性能参数，该模块通过控制激光器温度来稳定其中心波长，为波分复用系统的应用提供了具备稳定中心波长特性的光源。     

集成运放的互阻抗放大技术应用

本文对集成运放在电子技术应用中互阻抗放大技术进行了分析讨论，给出了相应的典型应用实例，具有重要的推广应用价值。     

1-Wire单总线器件技术规范及应用研究

1-Wire单总线是一种特殊串行数据通信方式,它具有结构简单、成本低廉、节省I/O资源、便于总线扩展和维护等优点。文章介绍了1-Wire单总线器件的若干技术规范及其应用设计,给出了单总线传感器件的典型应用电路实例,并分析了1-Wire单总线器件实际应用中存在的问题。     

专用型运算放大器在精密仪器仪表中的应用

对精密运放、高速运放、低噪声运放、视频运放等专用型运算放大器及其在仪器仪表中的应用技术进行了分析讨论,给出了几种典型应用实例,具有较高的实用价值。     

操控台结构优化设计及运输包装方法研究

目的 解决操控台在按照振动试验考核过程中出现的内部结构散架、表面磨损等问题,通过振动试验考核,满足恶劣颠簸路段运输要求。方法 对操控台进行力学仿真,对操控台结构最大等效应力处进行优化设计,提出一种加固木箱填充聚氨酯发泡材料的包装方法,采用有限元仿真计算和剩余强度系数公式评估强度安全,并通过随机振动试验进行验证。结果 优化结构及改进包装后的操控台剩余强度系数大于1,随机振动试验后台体及包装箱未出现损坏现象。结论 操控台结构优化方式和新型包装方法具有合理性,满足振动试验考核和恶劣颠簸路段运输要求。     

瓦斯涌出规律及综合防治措施

介绍高瓦斯矿井针对瓦斯涌出规律及来源，采取各种防治措施，从而保证工作面的安全生产。     

A novel three-ring-core few-mode fiber with large effective area and low nonlinear coefficient

A novel three-ring-core few-mode fiber with large effective area and low nonlinear coefficient is proposed in this paper. The fiber characteristics based on the full-vector finite element method (FEM) with perfect matched layer boundary conditions show that four supermodes with large effective area, low nonlinear coefficient and low differential mode group delay (DMGD) are achieved. With the increase of input wavelength, the effective areas of three-ring-core few-mode fiber are increased, and the nonlinear coefficients are decreased. The bending losses are increased with the increase of input wavelength, and are decreased with the increase of bending radius. Moreover, the proposed fiber performs a nonlinear coefficient and DMGD flattened profile at a large wavelength range.     

光脉冲特性测量和分析的新方法

文章给出并采用了光脉冲特性分析新方法,对10 GHz光脉冲在色散平坦光纤中的线性传输前后的时域波形、相位和时间带宽积等作了深入研究,并与数值计算得到的双曲正割和高斯光脉冲线性传输特性作了比较,对光脉冲的时域波形、啁啾等作出了更准确的判断,进一步证实了光脉冲的二次谐波-频率分辨光学门测量及其分析新方法的可靠性和准确性.     

短脉冲在色散平坦光纤中传输前后波形、相位和啁啾测量的实验研究

二次谐波频率分辨光学门(SHG-FROG)是能够准确测量短脉冲多项特性参量的新技术。利用二次谐波频率分辨光学门脉冲分析仪对在色散平坦光纤中传输前后的短脉冲进行了测量,得到了待测光脉冲的频率分辨光学门(FROG)图、自相关曲线、自相关频谱曲线、波形和相位曲线以及脉宽、谱宽、啁啾等反映短脉冲特性的信息,对实验结果进行了分析,并与高斯脉冲在单模光纤中的线性传输理论进行了比较。结果表明,激光器输出的短脉冲是具有负线性啁啾的近变换极限高斯脉冲,经过12.7 km色散平坦光纤传输后仍然为具有负线性啁啾的高斯脉冲,其谱宽在传输过程中基本保持不变,脉宽展宽了3.1倍,啁啾增大了4倍。实验测量结果和理论预期一致。     

A dispersion flattened fiber front-haul transmission system with high bitrate signal at low input optical power

We propose a dispersion flattened fiber (DFF) front-haul transmission system with high bitrate, polarization multiplexing (PM) and quadrature amplitude modulation (QAM) signal at low input optical power. The modulation format of the system is PM-16QAM, and the bitrate is 256 Gbit/s. The transmission characteristics over DFF link system are experimentally studied, which are compared with those over non-zero dispersion shifted fiber (NZDSF) link and standard single mode fiber (SSMF) link. The experimental results show that the error vector magnitude (EVM) of 256 Gbit/s and PM-16QAM signal over 25 km DFF link is 0.75% better than that over 25 km NZDSF link at least, and the bit error rate (BER) and Q-factor are much better than those of NZDSF. Their EVM and BER are both decreased with the increase of input optical power, and the Q-factor is increased. Those characteristics over 25 km SSMF are the worst at the same case. The larger the dispersion is, the more the constellation points are deviated from their respective centers and the worse the constellation characteristics are. The greater the attenuation of the DFF is, the smaller the input power of the DFF is, the more the constellation points are deviated from their centers and the worse the constellation characteristics are. This study provides a new idea and experimental support for long span front-haul propagation in mobile communication.