外差检测BOTDR系统中微波下变频器的研究与设计  

Design of Microwave Down-conversion Scheme in BOTDR System Based on Heterodyne Detection

作　　者：徐涛[1] 张吉生[1] 

机构地区：[1]华北电力大学电气与电子工程学院,河北保定071003

出　　处：《电力科学与工程》2009年第3期42-46,共5页Electric Power Science and Engineering

摘　　要：根据外差检测BOTDR系统的原理和对布里渊散射信号检测的要求,计算了光电检测器中布里渊频散射信号的频谱宽度和输出功率。针对系统对布里渊散射信号进行扫频检测的特殊要求,结合超外差接收机原理,提出了直接下变频和二次下变频两种方案,并对这两种方案的性能及可实现性等进行了系统的分析与比较。According to the principle of BOTDR system based on heterodyne detection and the requirement of Brillouin scattering detection, spectrum width and output power of the Brillouin scattering in the photo detector has been calculated. For the special requirement of frequency sweeping detection of Brillouin scattering in the system, two kinds of schemes were presented considering the principle of beterodyne receivers, which were direct-down-conversion and twice frequency down-conversion. The performance and the realization of the two kinds of schemes were analyzed and compared respectively.

关 键 词：光纤传感 扫频 布里渊散射 外差检测 直接下变频 二次下变频 

分 类 号：TN253[电子电信—物理电子学]