Doppler

What it does

Recently I stumbled upon an interesting paper for implementing motion sensing requiring no special hardware, only a speaker and mic ! Unfortunately the paper didn't include code to test it, so I decided to reproduce it here on the web! First of all, what is the doppler effect? The doppler effect is a physical phenomenom which affects waves in motion. The standard example is the effect on a fire engine siren as it quickly drives past. When it moves towards you the sound waves are compressed, and so the frequency becomes higher , and when it moves away from you the frequency becomes lower . This phenomenon actually has really wonderful applications in astronomy for figuring the speed at which…from danielrapp.github.io

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