
FCC approves first wireless power at a distance charging system - tempay
https://www.engadget.com/2017/12/26/fcc-approves-first-wireless-power-at-a-distance-charging-syste/
======
supermdguy
For some more details, you can look at there press release[0]. It says the
device "can deliver power via radio frequency (RF) energy to WattUp-enabled
electronic devices at a distance of up to three feet".

You could also listen to their conference call[1] where they "review the FCC
certification details in greater depth and answer questions". I haven't gone
through it, though.

[0] [https://ir.energous.com/press-
releases/detail/596/energous-r...](https://ir.energous.com/press-
releases/detail/596/energous-receives-industry-first-fcc-certification-for)

[1]
[https://services.choruscall.com/links/watt171227.html](https://services.choruscall.com/links/watt171227.html)

~~~
Steko
Blog with some analysis and a lot of older info on Energous:

[https://liesandstartuppr.blogspot.com/2017/12/energous-
and-f...](https://liesandstartuppr.blogspot.com/2017/12/energous-and-fcc-
approval-for-mid-range.html)

Previously on HN:

CES announcement (3 years ago)

[https://news.ycombinator.com/item?id=8860644](https://news.ycombinator.com/item?id=8860644)

Apple reported working with Energous (1 yr ago)

[https://news.ycombinator.com/item?id=12508409](https://news.ycombinator.com/item?id=12508409)

------
1001101
... and shareholders were richly rewarded:
[https://www.bloomberg.com/quote/WATT:US](https://www.bloomberg.com/quote/WATT:US)

(the stock was up 168.10% on the day)

~~~
vxNsr
Also first time since IPO that it's above the IPO price. Right on time for the
first employees to cash out.

Everybody wins!

------
exabrial
I can't seem to get any info on how much power is actually
transmitted/received... it's hard to beat the Inverse Square Law.

~~~
deepspace
It looks like the FCC approval pertains to a device delivering ~10W at a
distance of 0.5m in the 900MHz band.
[https://apps.fcc.gov/oetcf/eas/reports/ViewExhibitReport.cfm...](https://apps.fcc.gov/oetcf/eas/reports/ViewExhibitReport.cfm?mode=Exhibits&RequestTimeout=500&calledFromFrame=N&application_id=B6rKOmC6QGs13hWdV%2FM5%2Fg%3D%3D&fcc_id=2ADNG-
MS300)

~~~
revelation
So what makes the radio waves magically drop off the face of the earth after
.5m? And who allows 40 dBm (much more if we're talking _at_ .5m distance) in
an ISM band?

I mean, that test report is making a lot of assumptions and setup constraints
that are now magically not present in the video..

~~~
deepspace
Yes, I have been trying (unsuccessfully) to get my head around how the test
setup would translate into a practical application. And that the certification
appears to violate the FCC's own 30dBm power limit in the 900MHz ISM band.
Very strange.

~~~
phasetransition
The ISM field strength levels here are defined in 47 Part 18.305. they are
measured in an anechoic chamber and inverse square law scaled to the field
strength at the stated distance.

Source: I used to work with RF lighting devices, which need to meet the levels
of 18.305(c), and were usually tested the same way in pre-compliance before
final OATS testing.

------
squarefoot
From the title: "from 3 feet away."

From article and press release: "of up to three feet."

As usual, the devil is in the details: one angstrom would satisfy the "up to
three feet" claim as well.

I also would like to see the actual throughput. Wasting say 10 watts to get 1
watt of available power because one doesn't want to use a cable seems pretty
lame to me.

------
smaili
> The transmitter converts electricity into radio frequencies, then beams the
> energy to nearby devices outfitted with a corresponding receiver.

Just curious, any thoughts on radiation impact to people?

~~~
empraptor
EDIT: I didn't consider dielectric heating
([https://en.wikipedia.org/wiki/Dielectric_heating](https://en.wikipedia.org/wiki/Dielectric_heating)).
Seeing as how microwave ovens have 500W rating on the low end, I assume heat
generated by 10W source can be dissipated fast enough that proteins don't get
denatured even if it's directed at a small area of the body.

Most energetic photon in radio frequencies has wavelength of 1mm and energy of
0.00124eV
([http://www.photonics.byu.edu/fwnomograph.phtml](http://www.photonics.byu.edu/fwnomograph.phtml))
I think. Would just pass through a single cell as cell is much smaller than
the wavelength. And 0.0012eV is really small amount of energy. "Van der Waals
bonds are weak bonds with a dissociation energy of about 0.01 eV"
([http://lamp.tu-
graz.ac.at/~hadley/ss1/crystalbinding/bonds/b...](http://lamp.tu-
graz.ac.at/~hadley/ss1/crystalbinding/bonds/bonds.php)) I wouldn't expect it
to do anything cellular/molecular level.

Not really a biology person so don't know if there's some effect on aggregate
of cells on the millimeter level that could be harmful. Human body's
electrical resistance inside is high and through skin is higher so I don't
expect much effect on that scale either?

~~~
tudorw
I'm no biology person either, but in terms of photons, I do find these
interesting;

'Biological tissues typically produce an observed radiant emittance in the
visible and ultraviolet frequencies ranging from 10−17 to 10−23 W/cm2 (approx
1-1000 photons/cm2/second).[1] This low level of light has a much weaker
intensity than the visible light produced by bioluminescence, but biophotons
are detectable above the background of thermal radiation that is emitted by
tissues at their normal temperature.

While detection of biophotons has been reported by several groups,[2][3][4]
hypotheses that such biophotons indicate the state of biological tissues and
facilitate a form of cellular communication are still under
investigation,[5][6] and claims that biophotons are responsible for physical
healing are unsupported. Alexander Gurwitsch, who discovered the existence of
biophotons, was awarded the Stalin Prize in 1941 for his mitogenic radiation
work.[7]'

[https://en.wikipedia.org/wiki/Biophoton](https://en.wikipedia.org/wiki/Biophoton)

------
tabeth
What are some situations that:

1\. Has a device in question draw less than the wireless charging could input
(both practical and theoretical). Obviously, unless it's OK with the device
still running in a "net negative" state, you'd want the wireless charging to
at least cover the device's use.

and

2\. Necessitate motion or usage, or in other words, have the item not be at
rest The idea here is that if the device primarily sits, there's little
advantage to wireless charging

\- Power tools, for example cover (2), however not (1).

\- An iPhone may cover (1), but not (2).

------
neom
Can't uBeam already do this??

[https://www.usatoday.com/story/tech/news/2017/06/01/ubeams-m...](https://www.usatoday.com/story/tech/news/2017/06/01/ubeams-
meredith-perry-shows-her-stealth-wireless-charging-technology-really-
works/102336880/)

~~~
deepspace
No. Perry's scam utilizes ultrasound, and it works as well as you would expect
if you do the math, i.e. pretty much not at all.

------
amerine
Is it normal to feel a tad bit scared of wireless charging?

~~~
jtolmar
Until it's been independently tested and used in the real world for a while,
it makes sense to be suspicious of any form of energy transmission or storage.
Energy is dangerous.

Just don't let the suspicion last long enough to become superstition.

~~~
mcguire
There is considerable wisdom in this response.

~~~
jtolmar
Thank you, but be careful. It sounds wiser because that last line is so pithy.

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derekmhewitt
Sounds really cool! I can't wait to charge my phone just by setting it on my
nightstand at the end of the day. And my smart watch, and my headphones.

~~~
pault
You can already do that? Apple has a charging pad for the iPhone X, watch and
earpods.

~~~
KitDuncan
I had a Nexus 5 a couple of years ago that could do that and I am sure there
have been phones way before that with induction charging.

------
IronWolve
Another Wattup company with tech specs in the faq
[http://energous.com](http://energous.com)

------
bsder
What's the proper way to flag these obvious PR pieces with no technical
information at all?

~~~
josephpmay
If you have enough karma there's a "flag" button, but I don't see any reason
to flag PR pieces that have useful information in them

~~~
bsder
Well, it's "useful" to know the FCC actually approved this, but it's at the
barest end of that. But this piece doesn't include even the barest of
technical details.

If it included things like which band (5GHz), what power (claimed to be 4
watts at 5 feet--how does that get by FCC?), or any other technological point,
I probably wouldn't be so annoyed.

As it stands, this is quite obviously a stock pump PR piece, and this company
has a history of doing this since at least 2014.

I do have a flag button, but I normally reserve that for things which are
ferociously offensive rather than just scummy.

