Velocity determination of single sound source based on Doppler effect

An algorithm is proposed for determination velocity of single moving sound source with uniform velocity and frequency. A synthesized sound signal is formed to simulating the moving sound source recorded by a fixed recorder, on which Hilbert transform is applied to obtain the instantaneous frequency of the sound signal. Utilize the Doppler Effect as a model, which describes the relationship between the velocity and instantaneous frequency, to fit sampled instantaneous frequency by Nonlinear least square, the velocity of a mobile can be obtained. Experimental results show that the accuracy of the obtained mobile’s velocity is affected greatly by the background noise. Wavelet and EMD are used to reduce the noise in the noisy sound signal and instantaneous frequency, respectively.