How does radar work?

Radar is a way to locate objects beyond the range of vision. The name "radar" was coined from the first letters of the words RAdio Detecting And Ranging.

A radar set is an electronic device that sends out pulses of radio waves. Objects (e.g., ships and aircraft) in the path of these pulses reflect them back to the radar set.

  • The time it takes for the reflected pulses to return indicates the object's range - how far away it is.

  • The direction from which the reflected pulses return tells the object's location.
The reflected pulses can be seen as spots of light or as an image of the object on a display which looks like the picture tube of a television set.
How imaging radar works
Picture modified from National Aeronautics & Space Administration

Originally developed as an instrument of war, radar today is used in controlling air traffic, detecting weather patterns, and tracking spacecraft.

"George Files" by Parenting the Next Generation