动态信号源数目盲估计方法研究  

Research on dynamic signal source number blind estimation method

作　　者：付强[1] 景博[1] 何鹏举 汤梦阳[3] 戚咪 Fu Qiang;Jing Bo;He Pengju;Tang Mengyang;Qi Mi(College of Aeronautics Engineerings Air Force Engineering University,Xi'an 710038,China;Research&Development Institute of Northwestern Polytechnical University in Shenzhen,Shenzhen 518057,China;School of Automation,Northwestern Polytechnical University,Xi'an 710072,China)

机构地区：[1]空军工程大学航空工程学院,西安710038 [2]西北工业大学深圳研究院,深圳518057 [3]西北工业大学自动化学院,西安710072

出　　处：《仪器仪表学报》2020年第4期119-128,共10页Chinese Journal of Scientific Instrument

基　　金：深圳市知识创新计划(JCYJ20170306154611415);西安市科技计划(2017086CG/RC049)项目资助。

摘　　要：针对目前盖氏圆盘准则(GDE)及其改进方法难以精确计算出变化的瞬时信号源数目的问题,提出了基于滑动窗口(SW)和相关系数(CC)相结合改进盖氏圆盘准则的GDE-SW-CC动态信号源数目盲估计方法。首先利用盖氏圆盘准则的盖尔圆半径在信号数量增长过程中不断更替变化的特性,将新盖尔圆半径减去旧半径得出整体信源中半径变化最大的动态段。其次采用滑动窗口算法对动态段进行分段精估计,得到每一个滑动窗GDE的判断阈值。然后将GDE的判断阈值作为滑动窗口的特征量,并计算它们之间的相关系数,根据相关系数的峰值位置区分动态窗口信号圆盘与静态窗口信号圆盘得到瞬时信号源数目。最后,通过计算机仿真以及实测数据实验验证了本文方法的有效性、通用性和实用性。计算机仿真对比实验结果表明,相比现有静态GDE,所提方法能快速判读信号的源个数并定位出动态变化的时间区域;在此基础上,结合所提方法与集合经验模态分解(EEMD)进行了欠定盲源分离情形下的动态源信号数目估计仿真实验,结果表明调整因子为0.2以上即可得到正确的估计;实测数据实验得出结果与仿真结果基本吻合,尤其当信号源数目减少时,GDE的估计正确概率从95%降低到4%,所提方法的估计正确概率从95%增高到97%。Aiming at the problem that the Gerschgorin disk estimator(GDE) and its improved algorithm cannot accurately calculate the number of changing instantaneous signal sources, an improved GDE method based on the combination of sliding window(SW) and correlation coefficient(CC) is proposed, which is called GDE-SW-CC dynamic source number blind estimation method. Firstly, using the characteristic that the Gerschgorin disk radius of the GDE changes constantly in the increasing process of the number of signals, the dynamic segment with the largest radius change in the whole source is obtained by subtracting the old radius from the new Gerschgorin Disk radius. Secondly, the sliding window algorithm is used to precisely estimate the dynamic segment, and the judgment threshold of GDE for each sliding window is obtained. Then, the judgment threshold of GDE is taken as the characteristic quantity of the sliding window, and the correlation coefficients among them are calculated. According to the peak position of the correlation coefficients, the dynamic window signal disk and the static window signal disk are distinguished to obtain the number of instantaneous signal sources. Finally, computer simulation and actual experiment data verify the effectiveness, universality and practicability of the proposed algorithm. The comparison of computer simulation and experiment results shows that compared with the existing static GDE, the proposed algorithm can quickly interpret the number of signal sources and locate the dynamic changing time region. On this basis, the simulation experiment on dynamic source signal number estimation in the case of underdetermined blind source separation was carried out with the proposed algorithm combining ensemble empirical mode decomposition(EEMD). The results show that the correct estimation can be obtained as long as the adjustment factor is greater than 0.2. The actually measured data in experiment are basically consistent with the simulation results. Especially when the number of signal sources decr

关 键 词：信源个数估计 动态信号源 盖氏圆盘准则 盖尔圆半径 相关性分析 

分 类 号：TH701[机械工程—仪器科学与技术] TN911.7[机械工程—精密仪器及机械]