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研究了基于 Ｗｉｇｎｅｒ－Ｖｉｌｌｅ分布的宽带回波到达时刻的估计方法。通过回波信号与参考信号Ｗｉｇｎｅｒ－Ｖｉｌｌｅ分布的时频相关，完成对回波到达时刻的估计。在此基础上，本文提出了瞬时频域相关和ＸＷＶＤ峰值估计两种改进方法。通过仿真研究，发现这两种改进估计方法在低信噪比（０ｄＢ）下具有很好的估计性能，估计均方误差可以达到克拉美－罗界，并且运算量也大大降低，有利于工程实时应用。最后，本文讨论了线性调频信号时宽和带宽对估计性能的影响。
The method to estimate the arrival time of broadband echo based on Wigner-Ville distribution is studied. The time-frequency correlation of the echo signal with the Wigner-Ville distribution of the reference signal is used to estimate the echo arrival time. On this basis, this paper presents two improved methods of instantaneous frequency domain correlation and XWVD peak estimation. Through the simulation research, we find that these two improved estimation methods have good estimation performance at low signal-to-noise ratio (0dB), the mean square error can be estimated to reach the Cramer-Rao bound, and the computational complexity is greatly reduced, which is in favor of real-time application. Finally, we discuss the effect of chirp width and bandwidth on the estimation performance.