If you want to measure the distance between the earth and the moon accurately to 15 cm, you won't get far with a tape measure. And the velocity of a speeding automobile is hard to determine with a stopwatch. Where simple tools fail, radar measurement technology can provide a solution. At DLR_School_Lab Oberpfaffenhofen a radar system which measures distance and velocity is ready and waiting for you. Find out how it works and discover the strengths and weaknesses of this technology.
By the time your experiment is over, you'll know how to detect objects with the help of microwaves, how to locate something, how to determine your velocity and in which direction you're moving, and even how to monitor air traffic.
Compared with optical and acoustic measurement, radar has considerable advantages. These are a consequence of how radar works. Radar actively sends out microwaves. The objects hit by these waves reflect them back, and at the places where these "echos" are captured they are systematically evaluated. The special characteristics of microwaves make it possible to use radar systems in all kinds of weather, day and night.
At DLR_School_Lab Oberpfaffenhofen it's fun to experiment. Discover how intelligent radar technology adjusts its approach to suit a particular task. How does it measure distances, and how can it find out velocities? In the first case a comparison between the emitted and reflected frequency plays a big role. In the second case, it's the Doppler effect that is decisive. In both cases, electromagnetic waves reach their target at the speed of light - But we're not revealing more just yet.
Further information: Airborne radar system