Ultra-wideband (UWB) life detection radar has found wide applications in anti-riot, rescue, and anti-terrorism actions due to its many advantages, such as strong penetrating ability, high distance resolution, and strong anti-interference ability. Therefore, research on human micro-tremor signal detection using UWB through-wall radar has much significance. As the echo signal of through-wall life detection radar is interfered by background noise clutter, the conventional method using the digital filter cannot effectively detect human micro-tremor signal. To solve this problem, this paper presents a human body micro-tremor signal detection algorithm. First, the frequency domain cumulation is used to increase the signal-to-noise ratio (SNR) of the echo signal, and then EMD is used for de-noising. This algorithm not only has the advantages of frequency domain cumulation, but also has the ability of EMD method for adaptive decomposition. Under low SNR, it overcomes the disadvantages of frequency domain cumulation and EMD method, the former being not real-time and the latter having ineffective clutter remove. The simulation results show that the algorithm not only improves the SNR of the radar echo signal, but also overcomes the disadvantage of frequency domain cumulation. The frequency of human respiration can be rapidly and accurately detected by processing the echo signal using this algorithm, which is a novel method for through-wall radar detection of weak signals.
JIANG Liubing
,
WEI Honglang
,
YANG Changyu
,
XU Tengfei
,
GUAN Sihai
. Micro-tremor Signal Detection Algorithm Based on Frequency Domain Cumulation Combined with EMD De-noising[J]. Science & Technology Review, 2014
, 32(19)
: 36
-42
.
DOI: 10.3981/j.issn.1000-7857.2014.19.005
[1] Li C, Cummings J, Lam J, et al. Radar remote monitoring of vital signs[J]. Microwave Magazine, IEEE, 2009, 10(1): 47-56.
[2] Staderini E M. UWB radars in medicine[J]. IEEE Aerospace and Electronic Systems Magazine, 2002, 17(1): 13-18.
[3] 潘水洋, 吴晶, 李烨. 冲激超宽带雷达生命信号提取的新方法[J]. 微波 学报, 2010, 26(6): 36-41. Pan Shuiyang, Wu Jing, Li Ye. A new method for vital signal extraction in impulse-based UWB radar[J]. Journal of Microwaves, 2010, 26(6): 36-41.
[4] 张洋, 王健琪, 荆西京, 等. HHT在生物雷达回波信号噪声抑制中的 应用[J]. 医疗卫生装备, 2012, 33(5): 14-17. Zhang Yang, Wang Jianqi, Jing Xijing, et al. Application of hilberthuang transformation for noise suppression in ultra wideband bio-radar echo signal[J]. Chinese Medical Equipment Journal, 2012, 33(5): 14-17.
[5] Boric-Lubecke O, Lubecke V M, Mostafanezhad I, et al. Doppler radar architectures and signal processing for heart rate extraction[J]. Mikrotalasna Revija, 2009, 15(2): 12-17.
[6] 魏崇毓, 李玲娟, 朱卫娟. 一种弱信号检测新方法分析[J]. 现代电子技 术, 2012, 35(5): 60-67. Wei Chongyu, Li Lingjuan, Zhu Weijuan. Analysis of a new method for weak signal detection[J]. Modern Electronics Technique, 2012, 35(5): 60-67.
[7] Huang N E, Shen Z, Long S R, et al. The empirical mode decomposition and the hilbert spectrum for nonlinear and nonstationary time series analysis[J]. Proceedings of the Royal Society of London, Series A: Mathematical, Physical and Engineering Sciences, 1998, 454(1971): 903-995.
[8] Lai C P, Ruan Q, Narayanan R M. Hilbert-huang transform (HHT) analysis of human activities using through-wall noise radar[C]// International Symposium on Signals, Systems and Electronics, 2007 (ISSSE '07), Montreal, Canada, July 30-August 2, 2007: 115-118.
[9] 倪安胜, 王健琪, 杨国胜, 等. 基于FFT频域积累的非接触生命参数信 号检测[J]. 第四军医大学学报, 2003, 24(2): 172-175. Ni Ansheng, Wang Jianqi, Yang Guosheng, et al. Non-contact lifeparameters signal detecting of frequency domain signal integration based on FFT[J]. Journal of the Fourth Military Medical University, 2003, 24(2): 172-175.
[10] Singleton R C. An algorithm for computing the mixed radix fast Fourier transform[J]. IEEE Transactions on Audio and Electroacoustics, 1969, 17(2): 93-103.
[11] 张崇超, 张长春, 张群英. EEMD在超宽带雷达生命信号提取中的应 用[J]. 电子测量技术, 2012, 35(4): 76-101. Zhang Chongchao, Zhang Changchun, Zhang Qunying. Application of EEMD in vital signal detection for UWB radar[J]. Electronic Measurement Technology, 2012, 35(4): 76-101.
[12] Wu Z H, Huang N E. A study of the characteristics of white noise using the empirical mode decomposition method[J]. Proceedings of the Royal Society of London, Society A: Mathematical, Physical and Engineering Sciences, 2004, 460(2046): 1597-1611.
[13] 张洋. 基于HHT的UWB生物雷达回波信号处理技术研究[D]. 西安: 第四军医大学, 2012. Zhang Yang. Application of HHT for noise suppression in radar echo signal[D]. Xi'an: The Fourth Military Medical University, 2012.
[14] Donoho D L, Johnstone J M. Ideal spatial adaptation by wavelet shrinkage[J]. Biometrika, 1994, 81(3): 425-455.
