基于两次谱分析的时延估计方法研究

时延估计是目标定位跟踪系统的关键技术之一,在水声、雷达、声探测等领域广泛应用。时延估计的基本方法是互相关法和相位谱法。互相关法时延估计分辨率与信号带宽近似成反比,因此很难估计多目标时延。相位谱时延估计只能估计单目标时延,并且存在相位解绕问题。本文提出了两次谱分析时延估计方法,即将互功率谱函数再次进行谱估计,二次谱峰值位置间距即为时延估计,这种方法既能够估计单目标时延,又能够估计多目标时延,并且不用相位解绕。仿真计算验证了两次谱时延估计方法的可行性。

Time delay estimation by two times spectral analysis

Time delay estimation is one of the key techniques on target location and tracking,which widely apply in sonar,radar,acoustic detection etc.Two fundament methods for time delay estimation are the correlation method and the phase method. The resolution of the correlation method is approximately inversely proportional to the signal bandwidth and so the correlation method can hardly estimate time delay of multi- target.The phase method can only be used to estimate time delay of single target with problem of unwrap phase.A method of time delay estimation by two times spectral analysis,where the time delay is the time interval between peaks of spectrum of the cross power spectral density,is proposed in the paper.It can be used to estimate time delay of not only single target but also multi-target without unwrap.It’s validated by simulation.