Zhao Xindan
School of Mechanical Engineering Xi’an Jiaotong University, Xi’an 710049, ChinaZhang Xiaodong
1. Key Laboratory of Education Minis try for Modern Design and RotorBearing System, Xi’an 710049, China; 2. School of Mechanical Engineering Xi’an Jiaotong University, Xi’an 710049, ChinaHou Chenggang
School of Mechanical Engineering Xi’an Jiaotong University, Xi’an 710049, ChinaNiu Hang
School of Mechanical Engineering Xi’an Jiaotong University, Xi’an 710049, China1. Key Laboratory of Education Minis try for Modern Design and RotorBearing System, Xi’an 710049, China; 2. School of Mechanical Engineering Xi’an Jiaotong University, Xi’an 710049, China
TH744
In order to solve the shortcomings of the existing demodulation system, which can not guarantee the cycle integrity of the driving voltage, a wavelength demodulation system based on realtime reference light path and the tunable FP cavity filter is proposed in this paper. The hardware signal conditioning circuit consists of twostage amplifier circuit and secondorder lowpass filter circuit, which is high signal to noise ratio and low cost; The software analysis and processing module consists of highprecision computer program, which is realtime data acquisition, processing and preservation. What’s more, a sampling point compensation algorithm which is proposed, which can make host copputer produce complete periodic voltage under any circumstance. The experimental results show: the maximum measurement error of the demodulation system is 34 pm, the measurement range is 40 nm, and the maximum tuning speed is 100 Hz. This system can satisfy the requirements of engineering practice.
