基于多频率聚焦与融合的相干辐射源时差直接定位方法  

A Direct Position Determination Method of TDOA Based on Multi-Frequency Focusing and Fusion for Coherent Radiation Sources

作　　者：李建峰[1] 朱珂慧 江航 张小飞[1] 吴启晖[1] LI Jian-feng;ZHU Ke-hui;JIANG Hang;ZHANG Xiao-fei;WU Qi-hui(College of Electronic and Information Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing,Jiangsu 211106,China)

机构地区：[1]南京航空航天大学电子信息工程学院,江苏南京211106

出　　处：《电子学报》2023年第8期2110-2117,共8页Acta Electronica Sinica

基　　金：中国高校产学研创新基金(No.2021ZYA0301);国家重点研发计划(No.2020YFB1807602,No.2020YFB1807604)。

摘　　要：为了提升分布式传感器场景下对于宽带辐射源的定位效果,本文提出了一种基于到达时间差(Time Difference Of Arrival,TDOA)的多频率聚焦与融合的相干辐射源直接定位(Direct Position Determination,DPD)方法 .首先,对衰减系数未知的传感器时域接收信号进行预处理,进行数据分段和频域变换,将宽带信号转化成若干个多快拍窄带频域信号;其次,根据最佳聚焦矩阵构造准则,构造聚焦矩阵,将各频率对应的信号聚焦到中心频率附近频谱能量最大的聚焦频率,得到聚焦后的接收数据;然后,根据子空间正交性建立关于辐射源位置的最小化代价函数,融合多个聚焦后的代价函数解决衰减系数未知的问题;最后,结合拉格朗日乘子法,通过网格点上代价函数值的谱峰搜索得到宽带辐射源的估计位置.所提方法可以在衰减系数未知的情况下实现相干辐射源的高精度定位,仿真和实际测试结果表明本文所提方法的有效性,在信噪比大于0 dB的四节点多径定位场景中,所提方法的定位性能较其他时差直接定位性能提升了30%以上.In order to improve the positioning performance of wideband emitters in distributed sensor scenarios,this paper proposes a multi-frequency focusing and fusion direct position determination(DPD)method based on time difference of arrival(TDOA)for coherent sources.Firstly,the time domain received data of the sensors with unknown attenuation co⁃efficients are preprocessed;data segmentation and frequency domain transform are performed;and the wideband data are converted into several multiple-snapshot narrowband frequency domain data.Secondly,according to the construction crite⁃ria of the optimal focus matrix,the focus matrix is constructed,and the signals corresponding to each frequency are focused to the focus frequency with the largest spectral energy near the center frequency to obtain the received data after focusing.Then,according to the subspace orthogonality,the minimized cost function of the emitter is established,and the problem of unknown attenuation coefficients is solved by fusing multiple focused cost functions.Finally,combined with the Lagrange multiplier method,the estimated position of the wideband emitter is obtained through the spectral peak search of the cost function values on the grid points.The proposed method can achieve high accuracy positioning under the condition of un⁃known attenuation coefficients.Simulation and real-world test results show the effectiveness of the proposed method.In four node multipath localization scenarios with a signal-to-noise ratio greater than 0 dB,the proposed method improves the positioning performance by more than 30%compared to other TDOA-based DPD methods.

关 键 词：宽带辐射源 频率聚焦与融合 时差 直接定位 分布式传感器 子空间法 

分 类 号：TN911.7[电子电信—通信与信息系统]