基于参考臂低频相位调制的微弱振动光学相干检测  

Optical coherence detection of weak vibrations based on low-frequency phase modulation of reference arm

作　　者：张烈山 张晓琳[1] 刘刚[2] 唐文彦[1] ZHANG Lieshan;ZHANG Xiaolin;LIU Gang;TANG Wenyan(School of Electrical Engineering and Automation,Harbin Institute of Technology,Harbin 150001,China;Shanghai Satellite Engineering Institute,Shanghai 200240,China)

机构地区：[1]哈尔滨工业大学电气工程及自动化学院,哈尔滨150001 [2]上海卫星工程研究所,上海200240

出　　处：《振动与冲击》2018年第19期146-152,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(61108073);上海航天科技创新基金项目(SAST2015029)

摘　　要：针对纳米级中高频微弱振动检测提出了一种基于参考臂低频相位调制的光学相干检测方法。分析了参考臂低频相位调制情况下,微弱振动相干检测信号的模型及其频谱分布特点,在此基础上提出了振动频率及振幅的解算方法。仿真研究表明所述能够准确解调出纳米级微弱振动的频率及振幅参数,并且表现出较强的抗噪和抗环境扰动的能力。搭建了一套光学外差相干系统对由水下声源激发的纳米级水表面波进行了探测实验,实验结果表明利用所述的方法能够精确测定微弱振动的频率,对其振幅的检测也表现出很高的测量重复性。参考臂低频相位调制相干方法为中高频微弱振动参数的检测提供了新的解决方案。An optical coherence method based on low-frequency phase modulation of reference arm was proposed to detect nanometer level weak vibrations with medium and high frequencies.The model and its spectral distribution characteristics of weak vibration coherence detection signals were analyzed under condition of low-frequency phase modulation of reference arm.Then,the demodulation calculation method for weak vibration frequency and amplitude was proposed.Simulation study showed that the proposed method can correctly demodulate the frequency and amplitude of weak vibrations with a stronger anti-noise and anti-disturbance capacity.An optical heterodyne coherent system was developed to do tests and detect nanometer level weak water surface waves excited by underwater acoustic source.The test results showed that the proposed method can accurately measure the frequency of weak vibrations;it can detect the amplitude of weak vibration with a good repeatability;the detection method based on low-frequency phase modulation of reference arm provides a new solving scheme for parametric detection of weak vibrations with medium and high frequencies.

关 键 词：微弱振动 低频调制 相干检测 

分 类 号：TH825[机械工程—仪器科学与技术] TH741[机械工程—精密仪器及机械]