What frequency are you using and over what bandwidth? How many dB down are your sidelobes from your main beam? Are you using parabolic reflectors for your primary antennas, how big are they relative to your wavelength (what's the beamwidth)? What role do meta-materials play, are they the collimating relay? What about the sidelobes on the relay?
Why do you think 100 mW/cm^2 is 'safe'? You must know from experience this is enough for tissue heating, even from sidelobes many dB down.
Over what ranges do you think this is feasible? With, say 20 km of free space path loss in the 2.4 GHz ISM and 40 dB antenna gain at each end you're going to be at least 50 dB down. Doesn't this mean for things like transmitting power to islands this tech is not useful?
Even if you start at 1 KW in (60 dBm), over 20 km the receiving antenna is going to get about 0-10 dBm, or milliwatts.
With the same generous setup at 1 km and 1 kW you get 10 watts at the far end.
The antenna size is governed by the wavelength and the distance between Tx and Rx (or relays).
There are no sidelobes. We are using near-field and catching close to 100% of the radiated energy.
Range is only limited by line of site and an antenna size which is practical. Mind you, we can reduce antenna size and increase range by using passive relays.
Using a phased array, operating in the near-field. strictly point-to-point between Tx/Rx.
At the moment we are working with about 60% end to end efficiency so sending 1kw means you will get 600w at the far end… not 1w :)
As far as I understand it near-field effects stop being relevant at a couple of wavelengths away from the transmitter. For 2.4ghz that would give you what, a meter of distance?
Can you link me to reading material explaining how an antenna can have no sidelobes?
Near-field is only a few wavelengths away when the antenna itself is a half wavelength in dimension. Otherwise you would calculate the size of the near field as a function of the physical dimension of the antenna and the wavelength: r2 = 2d^2/λ.
E.g. The radiating near field of a 2.4GHz antenna about 8 meters long would extend about 1km.
Right, but even a phased array will give you sidelobes, it's only a question about reducing them, right? Your claim that there are no sidelobes at all seems a bit dubious to me.
Or is there some metamaterial "magic" going on even at the transmitter that I'm not accounting for?
Right, and anybody who knows enough to ask you about sidelobes likely also knows enough to know that too.
That's why, if you reply that "there are no sidelobes" you're only harming your own credibility.
A good reply is something like "there are sidelobes, but they peak at -{believable number} dB and are contained to within {small area}. We believe this is more than sufficient to address sidelobe concerns because of {standards}".
"I'm not disclosing basic performance metrics because you might reverse engineer my secret sauce from the basic performance metrics"? Really? Seems unlikely.
Yeah, there aren't enough details here to prove the claims. Not to mention, how much power do the "transmitting relays" use. Those sound like they need to be active devices that require a power source. Yes you can siphon off power from the beam, but with all the losses involved it doesn't seem to make sense.
Does this mean that the meta-material lenses are custom built for each relay station? For example, to bend the beam around fixed obstacles like a mountain. Do you believe this will be a barrier to manufacturing and installation?
Or are you creating a generic lens that is factory tuneable to the needed characteristics?
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).
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.
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.
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 :)
This reference from 2007 wherr a lab at MIT demonstrated wireless power transfer, may be relevant for explaining inductive coupling and the idea that this is not radiative (far field) power transfer - correct me if this technology is fundamentally different:
Coupling has nothing to do with Emrod tech. Its intrinsically limited to low power and small range. It is also has a much more significant impact on health and safty.
Ok understood. The "near field" comment made me think it was the same thing... I don't understand how this works then (not a criticism, just a walking back from thinking I got it)
Indeed [1]. For context I design antennas for a living (yes including "meta-materials", AESA, and high power), so not the first wireless power transfer design I've encountered. If this is different, awesome, I'd love to read a whitepaper.
All I'm saying is I hope you have a background in EM. There's lots of stuff that sounds great in approximation and models, but breaks down in reality.
[1] G=4piA/lambda^2 - I tacked on 70% eff which is mid-high for a parabolic dish
You posted personal attacks repeatedly in this thread. If you do that again we will ban you. We've had to warn you more than once about breaking the site guidelines already.
If someone else is making false claims, show how the claims are false, so we can all learn something. Don't just tell that they're false and especially not in noxious ways like this. Not only do you poison the community when you post like this, you also discredit any truth that you're trying to defend: https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor...
Other commenters have expressed skeptical reactions while staying within the guidelines. Please be like them in the future.
By the way, the claims in the OP probably are too good to be true, because most claims are too good to be true. But if we're to have an interesting forum in the long run, people need to correct bad information by respectfully providing good information, not by bashing each other in uninformative ways. Perhaps you don't owe someone who is making false claims better (I'm speaking only of the general case here, not the OP)—but you definitely owe this community better if you're posting to it. Please do better from now on.
Why do you think 100 mW/cm^2 is 'safe'? You must know from experience this is enough for tissue heating, even from sidelobes many dB down.
Over what ranges do you think this is feasible? With, say 20 km of free space path loss in the 2.4 GHz ISM and 40 dB antenna gain at each end you're going to be at least 50 dB down. Doesn't this mean for things like transmitting power to islands this tech is not useful?
Even if you start at 1 KW in (60 dBm), over 20 km the receiving antenna is going to get about 0-10 dBm, or milliwatts.
With the same generous setup at 1 km and 1 kW you get 10 watts at the far end.
This just doesn't work out.