Improved Capon Estimator for High-Resolution DOA Estimation and Its Statistical Analysis  

作　　者：Weiliang Zuo Jingmin Xin Changnong Liu Nanning Zheng Akira Sano 

机构地区：[1]IEEE [2]the National Key Laboratory of Human-Machine Hybrid Augmented Intelligence,the National Engineering Research Center for Visual Information and Applications,and the Institute of Artificial Intelligence and Robotics,Xi’an Jiaotong University,Xi’an 710049,China [3]the Data Center,China Construction Bank,Beijing 100033,China [4]the Department of System Design Engineering,Keio University,Yokohama 223-8522,Japan

出　　处：《IEEE/CAA Journal of Automatica Sinica》2023年第8期1716-1729,共14页自动化学报（英文版）

基　　金：supported in part by the National Natural Science Foundation of China(62201447);the Project Supported by Natural Science Basic Research Plan in Shaanxi Province of China(2022JQ-640)。

摘　　要：Despite some efforts and attempts have been made to improve the direction-of-arrival(DOA)estimation performance of the standard Capon beamformer(SCB)in array processing,rigorous statistical performance analyses of these modified Capon estimators are still lacking.This paper studies an improved Capon estimator(ICE)for estimating the DOAs of multiple uncorrelated narrowband signals,where the higherorder inverse(sample)array covariance matrix is used in the Capon-like cost function.By establishing the relationship between this nonparametric estimator and the parametric and classic subspace-based MUSIC(multiple signal classification),it is clarified that as long as the power order of the inverse covariance matrix is increased to reduce the influence of signal subspace components in the ICE,the estimation performance of the ICE becomes equivalent to that of the MUSIC regardless of the signal-to-noise ratio(SNR).Furthermore the statistical performance of the ICE is analyzed,and the large-sample mean-squared-error(MSE)expression of the estimated DOA is derived.Finally the effectiveness and the theoretical analysis of the ICE are substantiated through numerical examples,where the Cramer-Rao lower bound(CRB)is used to evaluate the validity of the derived asymptotic MSE expression.

关 键 词：Capon beamformer direction-of-arrival(DOA)estimation large-sample mean-squared-error(MSE) subspace-based methods uniform linear array 

分 类 号：TN911.7[电子电信—通信与信息系统]