Author Affiliations
Abstract
1 Department of Physics, Jimei University, Xiamen 361021, China
2 Department of Electronics Engineering, Xiamen University, Xiamen 361005, China
In this paper, we present a method based on self-mixing interferometry combing extreme learning machine for real-time human blood pressure measurement. A signal processing method based on wavelet transform is applied to extract reversion point in the self-mixing interference signal, thus the pulse wave profile is successfully reconstructed. Considering the blood pressure values are intrinsically related to characteristic parameters of the pulse wave, 80 samples from the MIMIC-II database are used to train the extreme learning machine blood pressure model. In the experiment, 15 measured samples of pulse wave signal are used as the prediction sets. The results show that the errors of systolic and diastolic blood pressure are both within 5 mmHg compared with that by the Coriolis method.
光电子快报（英文版）
2020, 16(6): 467
Author Affiliations
Abstract
1 Department of Electronic Engineering, Xiamen University, Xiamen 361005, China
2 The First Affiliated Hospital of Xiamen University, Xiamen 361005, China
In this paper, a technique based on laser self-mixing effect for acquiring pulse wave profile is proposed and demonstrated. For the characteristics of extremely weak vibration in human pulse waves, a method of multiple reflections with external cavity is designed to improve the measurement accuracy to λ/4. Based on the fringe counting algorithm, one period of pulse wave is successfully reconstructed. The measurement results show that the root mean square error (RMSE) of the reconstructed pulse wave is 0.912 μm at sampling rate of 8 kHz. Besides, the correlation coefficients and heart beats of this method and the traditional photoplethysmography (PPG) measurement are analyzed.
光电子快报（英文版）
2017, 13(2): 143
Author Affiliations
Abstract
1 Department of Physics, Jimei University, Xiamen 361021, China
2 Department of Electronics Engineering, Xiamen University, Xiamen 361005, China
Self-mixing interference (SMI) technique can be used for measuring vibration, displacement, velocity and absolute distance. In this paper, a simple demodulation algorithm for fast measuring frequency and amplitude of a simple harmonic vibration target is proposed based on the basic theoretical model of self-mixing interference effects. The simulative results show that the error between the vibration parameters which are demodulated by this algorithm and initial settings merely results from the sample rate. Further, the experimental system of self-mixing vibration measurement is built. The experimental results have a good agreement with simulation analyses. The maximum error of frequency demodulation is less than 1 Hz in our experiment.
光电子快报（英文版）
2014, 10(4): 304
1 厦门大学电子工程系， 福建 厦门 361005
2 福建省三明市计量所， 福建 三明 365000
根据光反馈自混合干涉效应的基本理论模型，通过求解适度反馈下的相位方程，讨论了半导体激光器的运行模态及特性，并搭建自混合干涉测量实验系统进行实验研究，与模拟仿真结果进行对比分析。在此基础上，实验研究表明扬声器的振幅与驱动电压成良好的线性关系。
自混合干涉 适度反馈 微振动测量 self-mixing interference moderate feedback micro-vibration measurement
