基于STM32H743的调频连续波位移传感器

Frequency Modulation Continuous Wave Displacement Sensor Based on STM32H743

针对线性调频连续波位移传感器信号采样率和信号处理速度低的问题,本文基于STM32H743芯片设计了一种法布里-珀罗干涉仪结构的光纤位移传感器。该光纤位移传感器使用锯齿波对激光器的频率进行调制,选用STM32H743作为核心处理器提高信号采集和处理速度,其主频为400 MHz,模数转换器最大转换速率为4.5 MHz,再结合调频连续波激光干涉测量技术对固定腔长的不锈钢钢管和运动目标的位移量进行测量。实验结果表明,该位移传感器在200~400 mm测量实验中,对1 mm/s运动目标的测量结果标准差小于3.3 nm,在600 mm范围内线性拟合系数在0.99998以上,其在位移测量领域具有良好的应用前景。

Aiming at the problem of low signal sampling rate and signal processing speed of linear frequency modulation continuous wave displacement sensor, this paper designs a fiber optic displacement sensor with a FabryPerot interferometer structure based on STM32 H743 chip. The optical fiber displacement sensor uses sawtooth wave to modulate the frequency of the laser, and selects STM32 H743 as the core processor to improve the signal acquisition and processing speed. Its main frequency is 400 MHz, and the analog to digital converter maximum conversion rate is 4. 5 MHz. Combined with frequency modulated continuous wave laser interferometry, the displacement of stainless steel pipe with fixed cavity length and moving target is measured. Experimental results show that in the 200-400 mm measurement experiment, the standard deviation of the measurement result of 1 mm/s is less than 3. 3 nm, and the linear fitting coefficient in the range of 600 mm is above 0. 99998, which has a good application prospect in the field of displacement measurement.