宽带双曲调频信号参数化时频分析波达方向估计

针对有源探测或脉冲侦查中双曲调频信号的波达方向估计问题,提出了基于参数化时频变换(PTFT)的多重信号分类(MUSIC)测向算法,简称PTFT-MUSIC算法。该算法由发射信号确定针对双曲调频信号的参数化变换核,对接收信号进行频域参数化时频变换,利用获得的时频分布建立阵列信号时频分布模型,并以此模型设计基于时频分布矩阵的MUSIC算法以实现双曲调频信号的波达方向估计。通过仿真和实验对该算法的估计误差和多目标分辨性能进行了分析,仿真和海上实验结果表明:相比现有的时频MUSIC算法,PTFT-MUSIC算法能有效提高空间谱分辨率和波达方向估计性能,同时该算法拥有对特定调频信号筛选性,结合时频域滤波算法能有效抑制相干直达波干扰,应用于多基地声呐系统时有效提高了声呐定位性能。

Direction of arrival estimation of wideband hyperbolic frequency modulation signals using parameterized time-frequency analysis

Aiming at the problem of Direction-of-Arrival (DOA) estimation of hyperbolic Frequency Modulation (FM) signal in active detection or pulse detection, a multi-signal classification direction finding algorithm based on Parameterized Time-Frequency Transform (PTFT-MUSIC) is proposed. The parameterized transform core of the hyperbolic FM signal is determined by the transmitted signal, and the frequency domain parameterized time-frequency transform of the received signal is carried out. The time-frequency distribution model of the array signal is established by using the obtained time-frequency distribution, and the MUSIC algorithm based on the time-frequency distribution matrix is designed to realize the DOA estimation of the hyperbolic FM signal. Through simulation and experiment, the estimation error and multi-target resolution performance of the algorithm are analyzed. The simulation and sea experiment results show that compared with the existing time-frequency MUSIC algorithm, the PTFT-MUSIC algorithm can effectively improve the spatial-spectral resolution and DOA estimation performance. At the same time, the algorithm has the ability to screen specific FM signals, combined with the time-frequency filtering algorithm, the coherent direct wave interference can be effectively suppressed. When applied to multistatic sonar system, the positioning performance of sonar is improved effectively.