基于解相干MUSIC的相干信源直接定位法研究

Research of Direct Position Determination in Coherent Signal Base on Improved MUSIC Algorithm

针对MUSIC(Multiple Signal Classification)直接定位法(Direct Position Determination)对相干信源直接定位能力下降甚至失效的问题,提出了解相干MUSIC(Improved MUSIC)直接定位算法。在对信源协方差矩阵共轭重构后,采用空间谱搜索方法,实现对相干信源的直接定位。基于解相干MUSIC直接定位法继承了解相干MUSIC算法对相干信源DOA(Di-rection Of Arrival)估计更准确的优点,能够在保证对非相干信源定位精度的同时,减小对相干信源定位的误差。仿真对比结果表明,该算法可用于对相干信源的直接定位,且在信源距离较近、低信噪比、小快拍情况下具有比经典MUSIC更好的分辨力。

The improved MUSIC algorithm is proposed to solve the problem that the ability to decline or even lose for coherent signal of MUSIC direct position determination.After the reconstruction of the source covariance conjugate,the direct position deter mination of the coherent source is realized by means of the space spectrum search.The direct position determination based on im proved MUSIC algorithm inherits and improved MUSIC algorithm's advantage of more accurate estimation of coherent source DOA,which can reduce the error of coherent source location while ensuring the accuracy of non-coherent source location.Simulation re sults show that this method applies to direct position determination for coherent signal.And it performs better than classic MUSIC even under nearer the distance of signals,low-SNR or low-snap situation.