相干信号波达方向估计技术综述

摘要

The received signals of array are coherent because of the reflection and refraction in the multipath propagation.The presence of coherent signals leads to the rank loss of signal covariance matrix,which results in the invalidity of conventional high-resolution direction of arrival(DOA) estimation methods.Therefore a variety of algorithms have been presented to solve this problem,which recover the rank of covariance matrix by utilizing the special property of steering vector.Recently,there has been a growing interest in deriving new algorithms that can reduce the loss of array aperture and increase the number of resolvable signals as well as the accuracy of DOA estimation.In this paper,the yield of coherent signals and their effect on DOA estimation are introduced,and the data models are established.Then,the coherent DOA estimation algorithms are presented class by class depending on their decorrelation approaches.Finally,the future research directions are prospected.%在信号的传输过程中,由于信号反射和折射,导致多径传输产生相干信号.此时信号协方差矩阵出现秩缺,导致传统的超分辨波达方向估计(Direction of arrival,DOA)算法失效.针对相干信号的DOA估计算法被提出,这些算法通过利用阵列导向矢量的特殊性质,对协方差矩阵的秩进行恢复,从而达到解相干的目的.围绕着减小阵列孔径损失、增加可处理信号数量和提高估计精度等目标,新的相干信号DOA估计算法不断被提出,成为阵列信号处理方向的一个研究热点.本文介绍了相干信号的产生和其对DOA估计的影响,给出了相干信号的阵列模型,根据解相干方式的不同,将各种相干信号的DOA估计算法进行分类,并逐类进行阐述,最后展望了相干信号DOA估计未来的研究方向.