| 摘要: |
| 阵元失效下多输入多输出(Multiple-Input Multiple-Output,MIMO)雷达虚拟阵列协方差矩阵出现大批整行整列元素缺失，破坏原有内在完整结构，导致波达方向(Direction of Arrival,DOA)估计性能下降。为此，提出一种联合核范数和SCAD(Smoothly Clipped Absolute Deviation)惩罚的完整协方差矩阵重构方法，以利于阵元失效下MIMO雷达DOA的有效估计。首先对待恢复的协方差矩阵建立核范数和SCAD惩罚双先验约束模型，并利用等正弦空间稀疏化方式划分粗网格空间，在可容忍的模型误差内能大大降低运算复杂度；然后利用ALM-ADMM(Augmented Lagrange Multipliers-Alternating Direction Method of Multipliers)算法对双先验约束模型进行求解，从而恢复协方差矩阵中大量整行整列的缺失数据；最后通过RD-ESPRIT(Reduced Dimensional ESPRIT)算法进行目标DOA估计。仿真结果验证该方法能快速恢复虚拟协方差矩阵中的缺失数据，从而有效提高阵元失效下MIMO雷达的DOA估计性能。 |
| 关键词: MIMO雷达 阵元失效 DOA估计 核范数和SCAD惩罚 ALM-ADMM算法 |
| DOI：10.20079/j.issn.1001-893x.211206001 |
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| 基金项目:国家自然科学基金资助项目（62071238，61701249）；江苏省自然科学基金资助项目（BK20191399，BK20160959） |
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| DOA estimation based on nuclear norm and SCAD penalty in MIMO radar under array antenna failure |
| CHEN Jinli,FU Shanteng,ZHU Xicheng,LI Jiaqiang |
| (a.Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters;
b.School of Electronic and Information Engineering,Nanjing University of Information Science and Technology,Nanjing 210044,China) |
| Abstract: |
| The presence of faulty antennas in multiple-input multiple-output(MIMO) radar destroys the data integrity of the virtual array covariance matrix,which induces a significant performance degradation of direction of arrival(DOA) estimation.A complete covariance matrix reconstruction method via jointly utilizing nuclear norm and smoothly clipped absolute deviation(SCAD) penalty is proposed to alleviate this negative effect caused by antenna failures.Firstly,a double priors’ constrained model is established,in which nuclear norm and SCAD penalty is utilized.A great trade-off between the coarse sampling grid and the modeling accuracy can be achieved,and thus gaining a considerably reduced computational cost.Thereafter,to recover the entire-row and entire-column missing data in the covariance matrix,this optimization problem is tackled properly under the Alternating Direction Method of Multipliers(ADMM) framework with the help of Augmented Lagrange Multipliers(ALM).Finally,based on the restored covariance matrix,the Reduced Dimensional ESPRIT(RD-ESPRIT) algorithm is applied to DOA estimation.Simulation results demonstrate that the proposed method can recover the missing entries of covariance matrix in a computationally inexpensive way,thus providing superior DOA estimation performance in MIMO radar under array antenna failure. |
| Key words: MIMO radar array antenna failure DOA estimation nuclear norm and SCAD penalty ALM-ADMM algorithm |
