Mark The Droner
Captain
Flight distance : 2917 ft
United States
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Cetaman's setup is unusual. My understanding of Lightbridge is that each antenna does a different job. There was a thread on PP where it was proven with testing equipment that each antenna performed different tasks. So I'm not sure if pointing the antennas in different directions would work as well as the conventional method of pointing them in the same direction. But it also depends on what kind of flying you're doing and what your goals are.
Re the windsurfer in general, I think it's easier if you understand phase-shift and then you can figure it out yourself. Otherwise you're just taking my word for it and who knows, I may be an idiot! Phase-shift is important and it's not something to be dismissed.
So I suggest you look at this vid which describes phase-shift nicely. https://www.khanacademy.org/test ... v/wave-interference
Now you know that you want the deflected signal to arrive at the receiver in phase with the LOS signal, which is to say you want the height of the deflected sine wave to arrive at the same time as the height of the LOS sine wave.
So once you've got your head wrapped around that, it's simple arithmetic. For example, if the distance between the two pole antennas (xmtr and rcvr) is exactly, one mile and zero inches. Then we know the LOS signal will travel exactly one mile and 0 inches. So what is a good distance for the deflected signal to travel?
Since we know the wavelength of a 2.4 ghz signal is 4.9 inches, and since we know the deflected wave is going to cover more distance than the LOS wave, what would be a good distance?
The answer, of course, is exactly 1 mile and 4.9 inches. So if you can position your windsurfer so that the deflected wave is traveling something close to 4.9 inches over the one mile, it would be near-perfect. And you could then say your windsurfer antenna is "tuned" to 2.4 ghz.
OTOH, the 5.8 ghz signal has a wavelength of 2.1 inches, so that is the extra travel you'd want on the deflected wave. Or 4.2 inches would work equally well.
This deflected signal concept in regards to phase shift is also explained on the fresnel zone wiki page.
Hope this makes sense to you.
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