Aiming to the existing problem that the poor stability and the low accuracy of FFT-based algorithm and Levenberg-Marquardt (LM) fitting algorithm in the heart rate evaluation, this paper proposes an improved heart rate estimation algorithm after analyzing the characteristics of the 77 GHz linear frequency modulated continuous wave (LFMCW) radar.Firstly, the algorithm recognizes the human body through the velocity-distance spectrum and obtains an permutation entropy (PE) interval[0.31,0.44] corresponding to the heartbeat interval of 50-120 beats/min through simulation experiments.Then, this paper proposes a PE heartbeat signal interval screening method to eliminate interference and noise in micro motion signals. Accurate evaluation of heart rate can be realized through peak detection algorithm. Finally, this paper invited 30 volunteers to conduct experiments, and evaluated and compared the algorithm proposed in this paper, FFT algorithm, and LM fitting algorithm from the aspects of stability, accuracy, and estimation error. Experiments show that the comprehensive evaluation indicator of the stability and estimation error of the algorithm proposed in this paper is the best with an accuracy of 98.30%.
LIAO Honghai
,
HE Wei
,
LIN Shuiyang
. Heart rate evaluation algorithm based on PE-based MEEMD filter in LFMCW radar[J]. Journal of University of Chinese Academy of Sciences, 2021
, 38(5)
: 666
-677
.
DOI: 10.7523/j.issn.2095-6134.2021.05.011
[1] Jalalibidgoli F, Moghadami S, Ardalan S. A compact portable microwave life-detection device for finding survivors[J]. IEEE Embedded Systems Letters, 2016, 8(1):10-13.
[2] Khan U M, Kabir Z, Hassan S A, et al. A deep learning framework using passive Wifi sensing for respiration monitoring[C]//IEEE Global Communications Conference. IEEE, 2017:1-6.
[3] 朱万里. 超声多普勒胎儿心率检测算法研究[D]. 沈阳:东北大学, 2011.
[4] Takano C, Ohta Y. Heart rate measurement based on a time-lapse image[J]. Medical Engineering and Physics, 2007, 29(8):853-857.
[5] Liang X, Zhang H, Ye S, et al. Improved denoising method for through-wall vital sign detection using UWB impulse radar[J]. Digital Signal Processing, 2018, 74(3):72-93.
[6] Wang G, Munoz-Ferreras J M, Gu C, et al. Linear-frequency-modulated continuous-wave radar for vital-sign monitoring[C]//IEEE Topical Conference on Wireless Sensors and Sensor Networks. IEEE, 2014:37-39.
[7] Ren L, Koo Y S, Wang H, et al. Noncontact multiple heartbeats detection and subject localization using UWB impulse Doppler radar[J]. IEEE Microwave and Wireless Components Letters, 2015, 25(10):690-692.
[8] 刘旭阳. 基于微波雷达的生命体征信号获取与处理技术[D]. 上海:东华大学, 2019.
[9] Liang S D. Sense-through-wall human detection based on UWB radar sensors[J]. Signal Processing, 2015, 126:117-124.
[10] 郑近德, 程军圣, 杨宇. 改进的EEMD算法及其应用研究[J]. 振动与冲击, 2013, 32(21):21-26.
[11] Wang G, Munoz-Ferreras J M, Gu C, et al. Application of linear-frequency-modulated continuous-wave (LFMCW) radars for tracking of vital signs[J]. IEEE Transactions on Microwave Theory and Techniques, 2014, 62(6):1387-1399.
[12] Bakhtiari S, Liao S, Elmer T W, et al. A real-time heart rate analysis for a remote millimeter wave I-Q sensor[J]. IEEE transactions on bio-medical engineering, 2011, 58(6):1839-1845.
[13] 拜军, 黄德生, 张骁,等. 基于生物雷达技术的非接触心率检测研究[J]. 医疗卫生装备, 2014, 35(3):10-13.
[14] Lazaro A, Girbau D, Villarino R. Techniques for clutter suppression in the presence of body movements during the detection of respiratory activity through UWB radars[J]. Sensors, 2014, 14(2):2595-2618.
[15] Kim J Y, Park J H, Jang S Y, et al. Peak detection algorithm for vital sign detection using Doppler radar sensors[J]. Sensors, 2019, 19(7):1-15.
[16] Wang G, Gu C, Inoue T, et al. Hybrid FMCW-interferometry radar system in the 5.8 GHz ISM band for indoor precise position and motion detection[C]//Microwave Symposium Digest. IEEE, 2014:16-19.
[17] 冯辅周, 饶国强, 司爱威,等. 排列熵算法的应用与发展[J]. 装甲兵工程学院学报, 2012, 26(2):34-38.
[18] Bandt C, Pompe B. Permutation entropy:a natural complexity measure for time series[J]. Physical Review Letters, 2002, 88(17):1-4.
[19] Su L, Wu H S, Tzuang C K C. 2-D FFT and time-frequency analysis techniques for multi-target recognition of FMCW radar signal[C]//Asia-Pacific Microwave Conference. IEEE, 2011:1390-1393.
[20] Wang J, Kasilingam D. Global range alignment for ISAR[J]. IEEE Transactions on Aerospace and Electronic Systems, 2003, 39(1):351-357.
[21] Morgan D R, Zierdt M G. Novel signal processing techniques for Doppler radar cardiopulmonary sensing[J]. Signal Processing, 2009, 89(1):45-66.
