独立信号和相干信号DOA估计新方法

Novel DOA estimation method for independent signals and coherent signals

传统的波达方向(direction of arrival,DOA)估计算法在独立信号和相干信号同时存在时往往失效或者性能下降;因而寻求可以同时估计独立信号和相干信号的测向算法具有重要意义。基于均匀线阵接收到信号的特点,提出了一种简单有效的独立信号和相干信号DOA估计新方法。该方法首先利用求根多重信号分类(root-mutiple signal classification,root-MUSIC)算法进行DOA估计,并根据相干源对应根的特点来消除相干信号的干扰,从而获得独立信号的波达方向;然后利用阵列接收数据协方差矩阵中独立信号的托普利兹(Toeplitz)特性,从中去除独立信号的数据分量,再利用改进矢量重构和总体最小二乘-旋转不变子空间(total least square-estimation of signal parameters via rotational invariance technique,TLS-ESPRIT)算法来估计相干信号的波达方向。理论分析和实验仿真结果表明,所提方法具有一定的阵列扩展能力,且计算量小、估计性能好。

Most classical direction of arrival （DOA） estimation algorithms often fall to estimate when deal-ing with both the independent signals, and the coherent signals simultaneously, so it is of great significance to find a new DOA estimation method to solve this problem. A novel DOA estimation method for both the inde pendent signals and the coherent signals is proposed. The process of estimation is divided into two steps. Firstly, the root-mutiple signal classification （root-MUSIC） algorithm is employed to estimate the DOAs of the independent signals, and the interference of the coherent signals is eliminated by utilizing the characteristics of the coherent signals. Then, the data covariance matrix which only contains the information of the coherent signals is obtained by exploiting the Toeplitz property of the independent signals, and the DOAs of the coherent signals are estimated with improved vector reconstruction technique and total least square estimation of signal parame ters via a rotational invariance technique （TLS-ESPRIT） algorithm. Theoretical analysis and simulation results show that the proposed method can expand the array aperture and has small computation load as well as excellent estimating performance.