【摘要】 本文主要介绍了一套分布式光纤振动传感系统中的数据采集及信号处理系统,该系统设计采用高性能的运算放大电路完成光电信号调理,以高精度差动模数转换器AD9246完成模数转换工作,并选用高性能FPGA作为核心逻辑控制器,并以低功耗的OMAP-L137作为CPU负责振动数据计算、网络通讯等工作,从而使该-OTDR分布式光纤振动传感系统测量范围扩展到25 km范围。本文通过计算相邻测点振动增量方法检测是否发生了振动入侵,提高了分布式光纤振动入侵检测的灵敏度。该设计方法提高分布式光纤振动传感系统的信噪比,使得该系统振动检测灵敏度提高、抗干扰能力增强,因此该分布式光纤振动传感系统可以用于实际工程的振动监控。更多还原

【Abstract】 This paper introduces a data acquisition and signal processing circuit of the distributed optical fiber vibration sensing system.In this system,one high performance operational amplifying circuit is adopted to modulate the photoelectric signal.One high-precision differential analog-to-digital convertor AD9246 is used to undertake the data conversion.A super FPGA XC6VLX365 works as the core logical controller.And the low power ARM chip OMAP-L137 fulfills the vibration data computation,network communication,etc.So the measurement range of the -OTDR distributed optical fiber vibration sensing system can be expanded to 25 km.The new vibration increment computation method of adjacent measurement point is used to detect the vibration intrusion and it gets a high vibration detection sensitivity in the distributed optical fiber vibration sensing system.This design method has significantly improved the signal-to-noise of the distributed optical fiber sensing system.So the vibration detection sensitivity and the anti-interference performance are improved.Then the distributed optical fiber sensing vibration system could be used in vibration monitoring of actual civil engineering.更多还原