运动声源多普勒畸变信号的一种时域校正方法
A time domain correction method for Doppler-distortion signal from acoustic moving source
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摘要: 运动声源信号中广泛存在多普勒效应的影响,为了解决其引起的频移、频带扩展问题,提出了一种时域信号校正方法。该方法首先从运动关系和莫尔斯声学理论出发推导得出离散插值时间序列和幅值还原公式,然后对畸变信号进行幅值还原和插值拟合。仿真信号和实验信号处理结果表明多普勒效应带来的频移和频带扩展问题得到了较好的解决,畸变信号得到了有效校正。该方法在时域内对离散信号进行单点操作,与以往的频域处理方法相比具有无需已知声源特征频率、不受频带混叠因素影响的优点,该方法能够处理多频信号,是一种简单有效的多普勒效应消除方法。Abstract: Doppler effect widely exists in the signal from the moving acoustic source, in order to solve such problems as frequency shift and frequency band expansion, a time domain correction method is presented in this paper. First, the discrete time series for interpolation and the amplitude restoration formula are obtained based on the moving relationship and the Morse acoustics theory, then the amplitude weights are corrected and the distortion signal is interpolated. Every single point of the discrete signal is operated separately in time domain, compared with the existed frequency domain methods, this method does not need to know the characteristic frequency beforehand and would not be influenced by the blending of the frequency band. This method can be used to correct multiple frequency signals and it is also a simple and effective Doppler-effect reduction method.