微弱激光功率检测方法与技术研究

【作者】 曾凯；

【导师】 段吉安；

【作者基本信息】 中南大学 ， 机械电子工程， 2011， 硕士

【摘要】 微弱激光功率检测系统最大的特点在于快速精确地检测微弱激光功率,用于测量激光信号传输衰减与损耗,在当代高速发展的光纤通信工程及相关科学实验和教学中起着重要的作用。针对目前微弱激光功率检测系统精度、速度、重复度越来越高的特点,对微弱激光功率检测方法和技术进行研究,探索微弱激光功率检测系统精确测量、信号搜索和监测跟踪的融合机制,研究灵敏度——精度——响应时间的相关规律,提出微弱激光功率检测系统设计方案。主要研究工作包括以下几个部分：1、检测系统噪声研究从噪声源入手,围绕噪声功率谱密度,建立噪声传递模型,提出了微弱激光功率检测系统噪声分析方法。采用Multisim工具,对噪声传递模型进行了仿真分析,结果表明：所提出的噪声分析方法可行,并且它为微弱激光功率计的硬件方案设计提供依据。2、微弱激光功率计硬件方案设计分析了微弱激光功率计的技术难点,提出了硬件系统的设计方案。主要从光探头参数选择、噪声网络匹配、放大电路设计、增益切换和误差消减等5个方面构建微弱激光功率计硬件。3、检测系统软件编译根据检测系统硬件需求,编译检测系统增益切换、误差消减、温度报警、通信及显示软件,并对检测结果进行自适应噪声抵消的程序设计。4、检测系统实验研究构建了微弱激光功率检测系统,检测结果表明：设计的微弱激光功率检测系统具有光功率检测功能,整体性能与设计指标相仿。其灵敏度为-60dBm、动态范围为70dB、响应时间处在毫秒量级。更多还原

【Abstract】 Weak laser power detection system, which can detect weak laser power quickly and accurately, is a kind of precise instrument in judging Laser signal transmission attenuation and loss, and play an important role in optical fiber communication engineering, related scientific experiments and teaching. Aimed at better performances of weak laser power detection system in precision, response speed and multiplicity, the methods and techniques of weak laser power detection are studied, fused mechanism of accurate measurement, signal search and monitor tracking are analyzed, and the rules between parameters of detection system are presented. The purpose of this work is to propose weak laser power detection system design scheme. The contents are presented as follows:1、Noise of detection system is researched.On the base of noise sources and noise power spectral density, noise transmission model is established and noise analysis method is analyzed. The results prove that the noise analysis method which can provide theoretical direction to the hardware construction of weak laser power detection system is right.2、A hardware system of detection system is proposed.Technical difficulties of detection system are analyzed. Then, solutions and design scheme of hardware system are present from probe preferences, noise networks matching, magnifying circuits design, gain switching and error cancelling.3、A software system of detection system is programmed.According to the requirements of hardware system, software block diagrams which include gain switching, error cancelling, temperature warning, communication and display of detection system are compiled, and adaptive noise canceller is used in the form of software.4、The error of debugged detection system is analyzed.A weak laser power detection system is debugged. The results prove that the hardware of the weak laser power detection system, which realize -60dBm sensitivity, 70dBm dynamic range and response time of ms level, is feasible and efficiency.更多还原