Re:Now, I can see wifi signals
by ChuckMcM on Saturday February 14, 2015 @08:13PM
(#9051421)
That is slick. The wavelength of 2.4Ghz radio being 125 mm and 5Ghz being 62.5mm it looks like he is imaging standing waves in the 5Ghz spectrum. (if the cube is 360mm x 360mm it would have ~6 waves of 5Ghz and ~3 waves of 2.4Ghz RF energy. There is an experiment to see the standing waves in a microwave using chocolate - http://morningcoffeephysics.com/measuring-the-speed-of-light... which demonstrates the same sort of thing, but frankly I think this is much cooler.
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Re:Now, I can see wifi signals
by pervycreeper on Saturday February 14, 2015 @09:30PM
(#9051585)
He does mention that explanation for explaining the distance between "features" in his visualization, however this does not explain their particular shape, nor their general irregularity. It would be nice to see this repeated outdoors in the desert to reduce reflections and possibly interference.
Re:Now, I can see wifi signals
by DonHopkins on Sunday February 15, 2015 @02:47AM
(#9052035)
It would also be nice to see the chocolate experiment repeated in other desserts.
only if you extract the Theobromine.
(hi don)
Reminds me of another project visualizing wifi signals:
> This project explores the invisible terrain of WiFi networks in urban spaces by light painting signal strength in long-exposure photographs.
> A four-metre long measuring rod with 80 points of light reveals cross-sections through WiFi networks using a photographic technique called light-painting.
* More Info: nearfield.org/2011/02/wifi-light-painting * Video: https://vimeo.com/20412632 * Thread on Hacker News: https://news.ycombinator.com/item?id=2270878
That is interesting also, but it is 1D only, the light stick's total illuminated length is signal strength. If they re-did that project using RGB LEDs and each LED colored from Red to Blue based on the signal strength at the LED then you would get a 2D plot, And of course if did as the author and photograph an LED at intervals in a 3D space you could do the 3D plotting.
The whole thing has my head buzzing with ideas. Imagine a drone which has a string of RGB LEDs hanging from it making such plot using GPS/6DOF IMU data to allow a computer to reconstruct the scene. Could be very cool indeed.
I was thinking the same about drones. Take a drone and let it automatically cover an area you're interested in. Maybe following a certain pattern or just random movement.
I tried that experiment once with marshmallows. Zero results and a lot of cleaning. :(.