NetLogo User Community Models

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Download If clicking does not initiate a download, try right clicking or control clicking and choosing "Save" or "Download".(The run link is disabled for this model because it was made in a version prior to NetLogo 6.0, which NetLogo Web requires.)

WHAT IS IT?

This model is a demonstration of how RADAR works.

RADAR is an acronym for RAdio Detection And Ranging

RADAR works by measuring the time it takes for a directed radio pulse to bounce off a distant object and return to the source.

The return time is directly proportional to the distance of the object related to the speed of light. ( d = t/2c )

A real radar pulse travels at the speed of light. Our radar is not so fast, but still works pretty well.

Sonor works in a similar fashion, but uses sound waves instead of radio waves.

HOW TO USE IT

Click Setup.
Click Go.

CONTROLS

sweep-angle
How many degrees the antenna turns between pulses.
reciprocate?
Whether the antenna sweeps in a circle, or goes back-and-forth.
ufo-speed
How fast the ufos move
RF-visible?
Makes the radar waves visible to the naked eye
resolution
adjusts the fineness of the simulation.
In practical terms, higher resolution means
the wave takes more steps to traverse the sky.

THINGS TO TRY

Adjust the sweep-angle, ufo-speed, and resolution.

Note how these variables affect the success of radar at finding the UFOs.

Use the slow-down slider to slow down time. Now you can follow the radio waves as they propigate out, bounce back, and are received again.

EXTENDING THE MODEL

How about doppler radar?

NETLOGO FEATURES

To get the sweeping single line of the scope, a custom turtle shape of a circle with a line from the center is used.
Since patch resolution is not important, but large shapes are, the model uses few patches and a large patch size.