Study on Respiration Signal Detection Algorithm of Ultra-WideBand Through-wall Radar Based on A Priori Signal-to-Noise Ratio Estimation
-
摘要: 废墟下呼吸信号的检测对地震救援具有重要意义。在实际中,障碍物(如墙体)后的人体呼吸信号会被环境中的噪声所掩盖。如何提升穿墙呼吸信号的信噪比(SNR)仍是一项具有挑战性的工作。该文提出一种基于先验信噪比估计的检测算法,用于增强穿墙弱呼吸信号的输出SNR。该算法在谱减法中典型的决策导向(DD)算法基础上加入了自适应权重因子,通过降低先验信噪比的估计误差来进一步消除残余随机噪声。通过仿真和实验验证了所提出算法的性能。与传统的快速傅里叶变换(FFT)、奇异值分解(SVD)和DD检测算法相比,所提出的呼吸检测算法的输出SNR有所提高。Abstract: The detection of respiration signal under the ruins is of great significance to earthquake rescue. In reality, the human respiration signal behind the obstacle (such as walls) will be masked by noise in the environment. How to improve the Signal-to-Noise Ratio (SNR) of the through-wall respiration signal is still a challenging task. A detection algorithm based on a priori SNR estimation for enhancing the output SNR of the weak through-wall respiration signal is proposed in this paper. Based on the typical Decision-Directed (DD) algorithm of spectral subtraction methods, an adaptive weighting factor is added in the proposed algorithm to eliminate further the residual random noise by reducing the estimation error of the a priori SNR. The performance of the proposed algorithm is investigated through simulation and experimental verification. The output SNR of the proposed respiration detection algorithm is improved compared with the traditional Fast Fourier Transform (FFT), Singular Value Decomposition (SVD), and DD detection algorithm.
-
表 1 不同墙体厚度下的输出SNR (dB)
墙厚(m) 0.12 0.24 0.37 FFT算法 12.13 11.10 10.06 SVD算法 18.97 17.28 14.37 DD算法 26.34 23.30 18.41 所提算法 32.83 30.80 27.67 表 2 UWB雷达参数
参数 参数值 信号模式 高斯脉冲 中心频率 500 MHz 带宽 500 MHz 瞬时功率 26 dBm 快时间等效采样率 16 GHz 慢时间采样率 13 Hz 表 3 两个静止目标的输出SNR (dB)
目标 目标1 目标2 FFT算法 9.37 7.49 SVD算法 10.30 8.73 DD算法 14.89 12.39 所提算法 21.68 18.73 -
[1] 晋良念, 欧阳缮, 周丽军. UWB MIMO穿墙雷达的阵列设计和成像方法[J]. 电子与信息学报, 2012, 34(7): 1574–1580. doi: 10.3724/SP.J.1146.2011.01113JIN Liangnian, OUYANG Shan, and ZHOU Lijun. Array design and imaging method for ultra-wideband multiple-input multiple-output through-the-wall radar[J]. Journal of Electronics &Information Technology, 2012, 34(7): 1574–1580. doi: 10.3724/SP.J.1146.2011.01113 [2] 刘新, 阎焜, 杨光耀, 等. UWB-MIMO穿墙雷达三维成像与运动补偿算法研究[J]. 电子与信息学报, 2020, 42(9): 2253–2260. doi: 10.11999/JEIT190356LIU Xin, YAN Kun, YANG Guangyao, et al. Study on 3D imaging and motion compensation algorithm for UWB-MIMO through-wall radar[J]. Journal of Electronics &Information Technology, 2020, 42(9): 2253–2260. doi: 10.11999/JEIT190356 [3] 李志, 金添, 周智敏. 超宽带虚拟孔径雷达非正交旁瓣抑制方法[J]. 电子与信息学报, 2012, 34(12): 2934–2941. doi: 10.3724/SP.J.1146.2012.00720LI Zhi, JIN Tian, and ZHOU Zhimin. Non-orthogonal Sidelobes reduction for virtual aperture UWB radar[J]. Journal of Electronics &Information Technology, 2012, 34(12): 2934–2941. doi: 10.3724/SP.J.1146.2012.00720 [4] YAN Kun, WU Shiyou, and FANG Guangyou. Detection of quasi-static trapped human being using mono-static UWB life-detection radar[J]. Applied Sciences, 2021, 11(7): 3129. doi: 10.3390/app11073129 [5] HARIKESH, CHAUHAN S S, BASU A, et al. Through the wall human subject localization and respiration rate detection using multichannel Doppler radar[J]. IEEE Sensors Journal, 2021, 21(2): 1510–1518. doi: 10.1109/JSEN.2020.3016755 [6] ROHMAN B P A, ANDRA M B, and NISHIMOTO M. Through-the-wall human respiration detection using UWB impulse radar on hovering drone[J]. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2021, 14: 6572–6584. doi: 10.1109/JSTARS.2021.3087668 [7] CAI Jiajia, ZHOU Hao, HUANG Weimin, et al. Ship detection and direction finding based on time-frequency analysis for compact HF radar[J]. IEEE Geoscience and Remote Sensing Letters, 2021, 18(1): 72–76. doi: 10.1109/LGRS.2020.2967387 [8] SCHLEICHER B, NASR I, TRASSER A, et al. IR-UWB radar demonstrator for ultra-fine movement detection and vital-sign monitoring[J]. IEEE Transactions on Microwave Theory and Techniques, 2013, 61(5): 2076–2085. doi: 10.1109/TMTT.2013.2252185 [9] 瑞泽, 熊明耀, 梁步阁. 穿墙雷达呼吸信号提取算法研究[J]. 电子技术, 2021, 50(7): 106–108.RUI Ze, XIONG Mingyao, and LIANG Buge. Study on algorithm of breathing signal extraction for through wall radar[J]. Electronic Technology, 2021, 50(7): 106–108. [10] LI Jing, LIU Lanbo, ZENG Zhaofa, et al. Advanced signal processing for vital sign extraction with applications in UWB radar detection of trapped victims in complex environments[J]. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2014, 7(3): 783–791. doi: 10.1109/JSTARS.2013.2259801 [11] WANG Kun, ZENG Zhaofa, and SUN Jiguang. Through-wall detection of the moving paths and vital signs of human beings[J]. IEEE Geoscience and Remote Sensing Letters, 2019, 16(5): 717–721. doi: 10.1109/LGRS.2018.2881311 [12] NEZIROVIC A, YAROVOY A G, and LIGTHART L P. Signal processing for improved detection of trapped victims using UWB radar[J]. IEEE Transactions on Geoscience and Remote Sensing, 2010, 48(4): 2005–2014. doi: 10.1109/TGRS.2009.2036840 [13] BOLL S. Suppression of acoustic noise in speech using spectral subtraction[J]. IEEE Transactions on Acoustics, Speech, and Signal Processing, 1979, 27(2): 113–120. doi: 10.1109/TASSP.1979.1163209 [14] PLAPOUS C, MARRO C, and SCALART P. Improved signal-to-noise ratio estimation for speech enhancement[J]. IEEE Transactions on Audio, Speech, and Language Processing, 2006, 14(6): 2098–2108. doi: 10.1109/TASL.2006.872621 [15] ALAM M, O’SHAUGHN ESSY D, and SELOUANI S. Speech enhancement based on novel two-step a priori SNR estimators[C]. INTERSPEECH 2008, 9th Annual Conference of the Ineternational Speech Commnication Association, Brisbane, Australia, 2008, 22–26. [16] SIM B L, TONG Y C, CHANG J S, et al. A parametric formulation of the generalized spectral subtraction method[J]. IEEE Transactions on Speech and Audio Processing, 1998, 6(4): 328–337. doi: 10.1109/89.701361 [17] SHI Cheng, NI Zhikang, PAN Jun, et al. A method for reducing timing jitter’s impact in through-wall human detection by ultra-wideband impulse radar[J]. Remote Sensing, 2021, 13(18): 3577. doi: 10.3390/rs13183577 [18] ROVŇAKOVá J and KOCUR D. Weak signal enhancement in radar signal processing[C]. 20th International Conference Radioelektronika 2010, Brno, Czech Republic, 2010: 1–4. [19] WARREN C, GIANNOPOULOS A, and GIANNAKIS I. GprMax: Open source software to simulate electromagnetic wave propagation for ground penetrating radar[J]. Computer Physics Communications, 2016, 209: 163–170. doi: 10.1016/j.cpc.2016.08.020 [20] WU Shiyou, TAN Kai, XIA Zhenghuan, et al. Improved human respiration detection method via ultra-wideband radar in through-wall or other similar conditions[J]. IET Radar, Sonar & Navigation, 2016, 10(3): 468–476. doi: 10.1049/iet-rsn.2015.0159