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.