What is the big deal about Doppler radar?
Early radar used radio interference to detect movement in the air of objects that would shift the appearance of the received waves. The directional high frequency radar was invented by the British. It sent out a large pulse of energy and timed its return to the receiver. That time divided by two was the distance to the object. Doppler radar sends out pulses of radio waves and measures their phase relationship to watch an objects motion and density in detail.
