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Microwaves are directed towards the object which reflect them back to the source and are detected and the distance is calculated similarly like the echo. that is distance= velocity of (microwave) x time (seconds).
OR
The transmitter sends the microwaves which is reflected back by the object and picked by the receiver.The distance is determined from the time taken for the signal to be reflected back since the time speed of the microwave is known.
joseph rimiru answered the question on October 28, 2017 at 09:47
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