一种改进的微弱NQR信号检测算法

波谱学杂志 ›› 2012, Vol. 29 ›› Issue (3): 393-400.

一种改进的微弱NQR信号检测算法

朱凯然^*，吴惠阳，郑纪彬，苏涛

西安电子科技大学雷达信号处理重点实验室, 陕西西安 710071

收稿日期:2011-11-21 修回日期:2012-03-20 出版日期:2012-09-05 发布日期:2012-09-05
基金资助:
国家自然科学基金青年科学基金资助项目(61001204), 中央高校基本科研业务费专项资金资助项目(JY0000902020), 陕西省“13115”科技创新工程资助项目(2009ZDKG-26).

An Improved Detection Algorithm for Detection of Weak NQR Signals

ZHU Kai-Ran^*, Wu Hui-Yang, ZHENG Ji-Bin, SU Tao

National Lab of Radar Signal Processing, Xidian University, Xi′an 710071, China

Received:2011-11-21 Revised:2012-03-20 Online:2012-09-05 Published:2012-09-05
Supported by:
国家自然科学基金青年科学基金资助项目(61001204), 中央高校基本科研业务费专项资金资助项目(JY0000902020), 陕西省“13115”科技创新工程资助项目(2009ZDKG-26).

摘要/Abstract

摘要：

核四极矩共振（NQR）是一种固态射频谱分析技术，可用于检测高危险爆炸物. 然而NQR信号本身非常弱，并且易受线圈的热噪声和外部射频干扰的影响，低信噪比限制了NQR的实际应用. 该文提出一种改进的微弱NQR信号检测算法. 首先利用Hankel矩阵方式下奇异值分解的方法，有效地抑制射频干扰和噪声，并将NQR信号分离出来. 然后提出了一种基于MUSIC谱估计的非线性最小二乘检测器，它既保证了高的频率分辨率，又大大降低了运算量. 仿真数据和实测数据结果表明该算法的有效性.

关键词: 核四极矩共振（NQR）, 非线性最小二乘检测器, MUSIC, 奇异值分解

Abstract:

Nuclear quadrupole resonance (NQR) is a solid-state radio frequency (RF) spectroscopic technique allowing the detection of many high explosives. However, the NQR signals are intrinsically weak, and the practical use of NQR is hindered by low signal-to-noise ratio (SNR), and artifacts arising from the thermal noise of the coil and external radio frequency interference (RFI). In this paper, we described an improved detection algorithm for detection of weak NQR signals. First, singular value decomposition using the Hankel matrix was utilized to restrain RFI and filter noise. A non-linear least squares detector based on the (multiple signal classification) MUSIC spectral estimation was applied, which not only guaranteed a high resolution in the frequency domain, but also led to significant reduction in the amount of computation. The effectiveness of this algorithm was demonstrated with the simulated and experimental results.

Key words: nuclear quadrupole resonance (NQR), non-linear least squares detector, MUSIC, singular value decomposition (SVD)

中图分类号:

O482.53

朱凯然, 吴惠阳, 郑纪彬, 苏涛. 一种改进的微弱NQR信号检测算法[J]. 波谱学杂志, 2012, 29(3): 393-400.

ZHU Kai-Ran, Wu Hui-Yang, ZHENG Ji-Bin, SU Tao. An Improved Detection Algorithm for Detection of Weak NQR Signals[J]. Chinese Journal of Magnetic Resonance, 2012, 29(3): 393-400.

参考文献

[1] Zhu Kai-ran(朱凯然), He Xue-hui(何学辉), Zheng Xiao-bao(郑小保), et al. The estimation of NQR parameters based on total least squares(基于总体最小二乘的核四极矩共振参数估计)[J]. Chinese Journal of Radio Science(电波科学学报), 2012, 27(1): 134-140.

[2] Zhu K, Su T, He X H, et al. 2010 Symposium on Security Detection and Information Processing[C]. Langford Lane: Elsevier Ltd, 2010.

[3] Gao Pan(高攀), Jin Yao-hui(金耀辉), Zhang Guo-jin(张国进), et al. An explosive detection method based on NQR(基于核四极矩共振原理的炸药探测方法研究与实验)[J]. Chinese J Magn Reson(波谱学杂志), 2008, 25(3): 371-378.

[4] Yang Zhen-lei(杨振磊), Xu Geng-guang(徐更光), Wang Zhen-hua(王振华), et al. A signal processing method for ¹⁴N nuclear quadrupole resonance detection of pentaerythritol tetranitrate(PETN炸药NQR信号处理方法)[J]. Chinese J Magn Reson(波谱学杂志), 2009, 26(4): 518-523.
[5] Garroway A N, Buess M L, Miller J B, et al. Remote sensing by nuclear quadrupole resonance[J]. IEEE T Geosci Remote Sens, 2001, 39(6): 1 108-1 118.

[6] Tan Y Y, Tantum S L, Collins L M. Cramer-Rao lower bound for estimating quadrupole resonance signals in non-gaussian noise[J]. IEEE Signal Proc Lett, 2004, 11(5): 490-493.

[7] Somasundaram S D, Jakobsson A, Butt N R. Countering radio frequency interference in single-sensor quadrupole resonance[J]. IEEE Geosci Remote Sens Lett, 2009, 6(1): 62-66.

[8] Jakobsson A, Mossberg M, Rowe M D, et al. Exploiting temperature dependency in the detection of NQR signals[J]. IEEE T Signal Proces, 2006, 54(5): 1 610-1 616.

[9] Gudmundson E, Jakobsson A, Stoica P. 2009 International Symposium on Signals, Circuits and Systems[C]. Hoes Lane: IEEE Computer Society, 2009.

[10] Zhao Xue-zhi(赵学智), Ye Bang-yan(叶邦彦). The similarity of signal processing effect between SVD and wavelet transform and its mechanism analysis(SVD和小波变换的信号处理效果相似性及其机理分析)[J]. Acta Electronica Sinica(电子学报), 2008, 36(8): 1 582-1 589.

[11] Nadler B. Nonparametric detection of signals by information theoretic criteria: Performance analysis and an improved estimator[J]. IEEE T Signal Proces, 2010, 58(5): 2 746-2 755.

[12] Xu Liang(徐亮), Zeng Cao(曾操), Liao Gui-sheng(廖桂生), et al. DOA and source number estimation method for strong and weak signals based on eigen beamforming (基于特征波束形成的强弱信号波达方向与信源数估计方法)[J]. Journal of Electronics & Information Technology(电子与信息学报), 2011, 33(2): 321-325.

[13] Umesh S, Tufts D W. Estimation of parameters of exponentially damped sinusoids using fast maximum likelihood estimation with application to NMR spectroscopy data[J]. IEEE T Signal Proces, 1996, 44(9): 2 245-2 259.

[14] Stoica P, Nehoral A. Music, maximum likelihood, and cramer-rao bound[J]. IEEE T Acoustics Speech and Signal Proces, 1989, 37(5): 720-741.

[15] Yang Zhen-lei(杨振磊), Xu Geng-guang(徐更光), Wang Zhen-hua(王振华), et al. An information database on detecting hidden explosives with NQR based methods(核四极共振隐藏炸药探测信息库设计)[J]. Chinese J Magn Reson(波谱学杂志), 2009, 26(3): 385-392.