Measuring Car Velocity via Acoustic Doppler Effect 

Velocity measurement can be done by fitting a Doppler model to the measured change in frequencies extracted from a sound sample.

Sound sample of a Doppler effect.

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Apply a continuous wavelet transformation with a Gabor wavelet.

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Antialiased subsampling of the wavelet data to 32Hz.

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Measure the scale shift via correlation.

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Convert shifts in wavelet scale back to change in frequency.

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Fit Doppler model to measured change in frequency.

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Result: car speed = 19.5 m/s minimum distance = 4.7m

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