Finding speed of vehicles using dopler shift

I am doing a project of finding the speed of vehicle using dopler shift. I will record the audio files of the vehicle arriving and departing at the stationary observer. From the audio i can get the spectrum of the signal. By correlating both audio files whether i could detemine the speed of the vehicle?

Answer 1

[David Young]

If the spectrum has a definite peak you can use that to estimate the dominant frequency of the sound before and after the vehicle passes. The change in frequency gives the speed, as per physics textbooks. If the spectrum does not have a clear peak, you will need a subtler way to find the frequency shift - there are various possibilities, but check out the simple idea first.