基于时反算子分解的时反高分辨率定位技术研究

基于时反算子分解技术,提出了主动时间反转选择性定位方法。为提高此定位方法的分辨率,根据时反算子和协方差矩阵的相似性,提出了时反MUSIC和对角线加载时反MVDR定位技术。传统的获取时反算子的方法是通过单个阵元依次发射,该方法的缺点是每次只有单个元发射,导致输入信噪比较小,本文提出通过多个波束正交发射获取时反算子,能得到较大的输入信噪比,从而改善三种定位方法的定位性能。波导实验分别对三种定位方法和正交发射技术进行了验证,结果显示三种定位算法中,子空间基于的时反MUSIC方法具有较好的定位精度,时反MVDR技术具有较高的分辨率。 

Study of time reversal highly resolved localization by decomposition of the time reversal operator

Based on the decomposition of the time reversal (TR) operator,the approach of active time reversal selective localization is put forward.To enhance the resolution of the approach,according to similarity between the TR operator and the covariance matrix,the techniques of TR multiple signal classification (MUSIC) location and TR minimum variance distortionless response (MVDR) location are presented.The conventional method to obtain the TR operator uses individual source array elements.The disadvantage of the method is that the input signal-to-noise ratios usually are quite low for each time only one element transmitting the signal.To achieve greater signal-to-noise ratios and improve the performance of the above three location techniques,the method of the source receiver array (SRA) probing by weighting orthogonal functions is put forward.The waveguide experiment demonstrates the three location techniques and the method of the orthogonal transmission.The experimental results show that the subspace-based TR MUSIC location has the least location error among the three location techniques,and the TR MVDR location has the highest resolution.