Last active
June 7, 2021 18:13
-
-
Save autocorr/ee3af8e34ae91c9391ee593082b0bab1 to your computer and use it in GitHub Desktop.
Ripple tank demos for radio astronomy and interferometry
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
# Ripple Tank Demos | |
Website available at: http://www.falstad.com/ripple/ . Copy and paste the following entries | |
by going under "File -> Import From Text...", beginning from the "$" until the blank line. | |
One can use the two check-boxes on the right to stop the simulation and visualize the | |
amplitdues in 3D. The sliders on the right can be used to adjust the rate/speed of the | |
simulation and wavelength/frequency of the wave (under "Source Frequency"). | |
Single point source. Point source limits to plane wave. | |
$ 1 512 64 10 0 668 0.048828125 | |
s 2 257 45 0 0.466666 0 10 100 1 0 | |
Two point sources. Double slit analog and constructive/destructive interference. | |
$ 1 512 64 10 0 689 0.048828125 | |
s 2 219 51 0 0.466666 0 10 100 1 0 | |
s 2 290 51 0 0.466666 0 10 100 1 0 | |
Focused wavepacket. A wavepacket is focused by a parabolic reflector, see in 3D to see increase in intensity. | |
$ 1 640 80 10 0 466 0.048828125 | |
p 0 54 479 568 597 0 | |
S 2 21 70 621 70 2 0.4999466723549488 0 2.944190050882948 883.2570152648844 1 0 | |
P 1 312 456 | |
P 1 164 252 | |
Primary beam. A parabolic reflect acting as a transmitter. Vary the frequency to change the width of the main lobe. | |
$ 1 512 64 10 1 738 1.5625e-8 | |
p 0 173 459 340 499 0 | |
s 2 256 455 0 1.166665 0 10 100 1 0 | |
Two element interferometer. Offset plane wave arriving at two parabolic reflectors. Traces show phase offset between antennas. The measured phase difference can be used to determine the angle. | |
$ 1 512 64 10 0 411 0.048828125 | |
p 0 86 435 215 460 0 | |
p 0 288 435 415 460 0 | |
S 2 2 61 509 5 0 0.5 0 10 100 1 0 | |
P 1 150 424 | |
P 1 352 424 | |
Slab in the sky. A line-source produces a bessel function in the far-field (equivalent to single slit). | |
$ 1 1007 125 10 0 654 0.039721946375372394 | |
S 2 450 48 559 48 0 1.166665 0 10 100 1 0 | |
P 1 499 994 | |
P 1 384 994 | |
Resolving two sources. Two point sources are in the sky. For two antennas close together, it appears as a plane wave, but the intensities will roll off and eventually reach the first null. | |
$ 1 1007 125 10 0 654 0.039721946375372394 | |
P 1 499 994 | |
P 1 384 994 | |
s 2 503 54 0 0.5 0 10 100 1 0 | |
s 2 545 54 0 0.5 0 10 100 1 0 | |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment