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Comment by Emrod | Hacker News Reader

efficiency is not a function of distance when there is no lose in the atmosphere :)

At the moment we are working with about 60% end to end efficiency

If path loss doesn't matter to you then you've revolutionized both communications and war.

There's spread over distance. If you've found a way to prevent spread it's either not free space or a change to the electromagnetics fundamentals. It's a really bold claim to make. But maybe I'm misunderstanding something.

Eliminating path loss has always been relatively easy if both ends never move. I’m assuming they mean negligible spread over the distance tested instead of no spread.

I work with radio, and I'm not sure how exactly you are "eliminating" path loss on any sort of real world link, even ones fixed in position. Even very high gain antennas and very small wavelengths are going to spread the energy out to some degree over any non-trivial distance (most links I work on are 10km+, so maybe your definition of non-trivial distances are different than mine).

> there is no lose in the atmosphere

I know bullshit when someone spells it out for me.

Maybe they found a frequency that is not absorbed by the athmosphere that much. Seems far-fetched with the gas mix that the athmosphere is, but I guess that such frequencies would be company IP.

Path loss through free space at these relatively low frequencies (<6 GHz) isn't from air/water vapor losses. It's from diffraction spread.

This company can say all they want about near field tech, but the beam waist diameter relative to wavelength determines the diffraction spread. And that aspect of path loss is proportional to the distance in wavelengths even if there's no "absorption" by the air components. For any reasonable link at 2.4-5.8 GHz the length in wavelengths will be tens of thousands.

The equations governing diffraction are relatively straight forward. We are operating within the near-field (or more accurately in the Frensel range). I'm sure you can do the math and see how focusing a phased array can reduce diffraction at this range :)

Just make sure to do your liability math because in a about a year you're going to have a lot of investors very angry at you.

Instruments that sweep all frequencies have been available since shortly after the dawn of radio and public atmospheric absorption tables have been available for nearly as long. Also, absorption bands tend to be very broad in this region, so after 10 or 20 data points there's nowhere for a magic frequency to hide.

You are correct. There's no magic at work here. We don't break the laws of physics, we just flex them with clever engineering... like most innovators that came before us.

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