提出了一种光纤Bragg光栅(FBG)压力传感器和基于相位产生载波(PGC)的干涉式波长解调相结合的传感器系统,实现脉象波形信息的探测。设计了一种高灵敏度的触点式FBG动态压力传感器,采用有限元软件分析了传感器的灵敏度和频率范围;对基于PGC的干涉式波长解调算法的低频特性进行了优化,实现低至0.2 Hz的高分辨率波长解调,以适应脉象信息测量的需要。实验研究了传感器的压力灵敏度,并进行了脉搏样本信号的采集。测试结果表明,传感器灵敏度为750pm/N,频率响应平坦,分辨率优于1.4×10^-6 N·H212,能够高保真的还原脉象信息,为客观化脉诊提供了一种可靠的技术途径。
A sensing system based on a combination of fiber Bragg grating(FBG)pressure sensor and interferometric wavelength demodulation based on phase generated carrier(PGC)is proposed to achieve the detection of pulse information in this paper.A highly sensitive point-contact type FBG dynamic pressure sensor is designed,and the sensitivity and frequency range of the sensor are analyzed by using the finite element method.The low frequency characteristic of the interferometric wavelength demodulation algorithm based on PGC is optimized,and a high resolution wavelength demodulation is realized as low as0.2Hz.The frequency response characteristics of the sensor are studied experimentally,and pulse signal samples are collected.Test results show that the sensor has a flat response of 750pm/N below 600 Hz with a resolution better than 1.4×10^-6 N·H_2~(1/2),which enable a high fidelity reduction of pulse information.