一种基于迭代自适应的离网格DOA估计方法  

An Off-Grid DOA Estimation Based on Iterative Adaptive Approach

作　　者：揭允康 张雯 李想 叶晓东[1] 王昊[1] 陶诗飞 JIE Yunkang;ZHANG Wen;LI Xiang;YE Xiaodong;WANG Hao;TAO Shifei(School of Electronic and Optical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China;Northern Institute of Electronic Equipment of China,Beijing 100191,China)

机构地区：[1]南京理工大学电子工程与光电技术学院,南京210094 [2]北方电子设备研究所,北京100191

出　　处：《电子与信息学报》2023年第10期3805-3811,共7页Journal of Electronics & Information Technology

基　　金：国家重点研发计划(2021YFB3502500)。

摘　　要：针对真实信源位置与字典网格不匹配导致波达角估计(DOA)误差过大的问题,该文提出一种基于修正迭代自适应(IAA)功率谱算法的离网格(Off-Grid)DOA估计方法(OGIAA)。该方法首先通过修正IAA方法得到信号功率谱,读出功率峰值的对应网格角度作为粗估计结果,再利用平方误差代价函数,将代价函数2阶泰勒展开并最小化得到初始偏移量,最后交替优化功率分量和偏移量,实现高精度的离网格DOA估计。理论分析和仿真结果表明,该方法实现过程简单,无正则化参数影响,能准确估计出偏移网格的信源角度,在高阵列自由度的非均匀阵列上也同样具备高估计精度。According to the problems that the mismatch between the real source location and the dictionary grid leads to the great error of Direction Of Arrival(DOA),an Off-Grid DOA estimation based on modified Iterative Adaptive Approach(IAA)is proposed(OGIAA).Firstly,the signal power spectrum obtained by the IAA is modified,and the corresponding grid angle of the peak power is read out as the coarse estimation results.Then,the square error cost function is expanded to the second order Taylor expansion and minimized to obtain the initial offset.Finally,the power component and offset are optimized alternately to achieve high precision off grid DOA estimation.Theoretical analysis and simulation results show that the implementation process of this method is simple,and it can accurately estimate the source angle of the migration grid without regularization parameters.It also has higher estimation accuracy on non-uniform arrays with more degrees of freedom.

关 键 词：DOA估计 离网格 自适应迭代 

分 类 号：TN97[电子电信—信号与信息处理]