
How pCell works and why its a bigger deal than anyone realizes - followben
http://akbars.net/how-steve-perlmans-revolutionary-wireless-technology-works-and-why-its-a-bigger-deal-than-anyone-realizes.html
======
StevePerlman
A couple of clarifications and comments (new whitepaper is coming with a lot
more info):

The iPhones (and dongles) we demoed have no software modifications at all, and
there is no additional overhead beyond the standard LTE protocol. pCell works
with unmodified Android LTE phones, too. (We had wanted to post a lab demo we
did of the Galaxy S4 and an Xperia, but we just ran out of time.) Out-of-the-
box compatibility is essential for rapid deployment. And, yes, we are meeting
many of the core goals of 5G today (e.g. unlimited 4K UltraHD streaming) using
Rel. 8 LTE devices in LTE spectrum.

pCell is indeed protocol agnostic, and can concurrently support different
protocols in different pCells in the same spectrum. For example, we can
support unmodified LTE phones in their own pCells, while concurrently
supporting lower cost/lower power devices with far lighter protocols (that are
lower latency), since we don't need all of the complexity of LTE. For example,
there are no cells, no cell edges (and no need for CoMP), and no cell handoff.

I'm waiting for something to connect the dots and realize this is a vastly
more efficient way to use white spaces than anything currently on the table.
White spaces will be full overnight with current techniques. With pCell, they
will never be full.

More data is coming later. Apologies. We have been utterly overwhelmed in
incoming inquiries since launch.

But, I will confirm this: pCell is indeed a much bigger deal than anyone has
yet touched on. The "tubes to transistors" analogy is not just marketing
speak: Compared to cellular, pCell is far more reliable, enables much smaller
and lower power device and can be continually extended in density. Tubes had
physical constraints that limited their reliability and scalability.
Transistors did not. Cellular (and other interference avoidance protocols like
Wi-Fi and cognitive radio) have a physical constraints that limit their
reliability and scalability. pCell does not (as far as we know). Cellular has
stalled in scalability. There is an entire era of innovation in front of us
with pCell. - Steve Perlman

~~~
tim333
> "no cell handoff" I'm curious how this would work. Presumably in the pCell
> system the base station focuses the radio signals in something like a beam
> towards the device but this must have a finite range - I wonder how far -
> and when you go out of range the system must switch to another base station.
> Maybe you call this a different name than 'handoff' but presumably the
> switching base stations thing must happen some how?

~~~
kristoffer
The pCell is "synthesized" using all base stations in range I guess. Which
base stations that are involved in your pCell changes as you move around ...

~~~
tim333
Ah - I see, thanks. I guess that's how they can focus the signal so narrowly
to 1 cm or so. Looking at the numbers the wavelengths used for 4G are of the
order of 1 ft so you wouldn't get much focus from a single aerial of similar
dimensions.

------
jtchang
I think the idea of focusing multiple low power radios onto a single point so
that they coalesce is simply being rediscovered. While we could do this before
the real ingenuity is being able to rapidly update all the parameters when the
point you want to focus onto is rapidly changing.

Another scary idea: While we could beam wireless power imagine if this was in
any way weaponized. With all these stations beaming power to everyone what
would it take for an overwhelming number of them to direct it at a target with
the purpose of eradicating it? Certainly not a laser in the traditional sense
but surely something just as destructive.

~~~
musesum
It doesn't have to be high power to be effective. Google search on "russian
microwave US embassy" (not Bing search, unfortunately), which yields some
interesting background on the Russian's beaming microwaves at the US Embassy.
It was within the US legal limit at the time. Health problem ensued. Making an
adversary sick without noticing may be more effective for some situations.

~~~
bri3d
[http://www.ehjournal.net/content/11/1/85](http://www.ehjournal.net/content/11/1/85)

The literature seems to indicate that the Russian microwave campaign resulted
in no measurable health effect to the employees at the embassy. This is
unsurprising because a wide variety of publications detailing similar
microwave exposure from modern electronic equipment like cellular towers,
phones, and WiFi access points seem to also indicate a negligible widespread
health effect.

~~~
politician
If you can transmit power to a 1cm bubble in space, you may be able to offset
it into, say, brain tissue. Brain tissue probably doesn't due too well under a
focused heat source.

~~~
ivanca
That's were magnetos helmet comes in. In all seriousness what material (or
device) could stop this from working?

~~~
tga_d
A simple Faraday cage, I would think. Hard part is making it look good.

~~~
Jack000
we're going to need that transparent aluminum

~~~
SixSigma
aka sapphire & ruby

------
ChuckMcM
Nice explanation, does it bother anyone else that you could set up a bunch of
antennas such that they could create a lethal 1 cm ball of energy anywhere in
the space they can see? Sure they think about powering devices but what about
a couple of Watt-Seconds of energy appearing in your frontal lobes? If Perlman
can do that its kind of the ultimate 'border' fence is it not?

(I'm tempted to write, "All you would need is an unscrupulous engineer to
develop a targeting system ...")

~~~
josephagoss
The first question that comes to mind is this: how can we defend ourselves
from being brain burnt?

~~~
simcop2387
Funniest part about that is that a foil hat might very well prevent it from
forming in the brain.

~~~
ChuckMcM
That is the funny part, and it would work. If you wore conductive clothing you
could create a faraday cage around yourself thus preventing RF energy from
crossing that boundary.

On a related note, discussing this offline with some friends they pointed out
that the pCell system is getting feedback from the phone about its signal
strength, and your body wouldn't be giving that feedback, so you would have to
have something tied into the pCell on your person (or not move). Your phone
could work for that. The question then is how far away from the phone can the
energy be localized while the feedback from the phone would still be accurate
enough. That I don't know.

~~~
simcop2387
Yea that's one thing I'm not sure about is how easily one could create it
without that feedback. I'm sure it'd be possible but certainly more difficult.

------
TheEzEzz
If the latency of pCell is low enough then you could have a thin-client phone
tunneling into a cloud OS. Now get rid of most of the CPU/memory hardware
complexity on the phone (which should lower power requirements for the phone
too). If you can wirelessly send energy then get rid of most of the battery.

Suddenly you've got a very, very thin phone with infinite battery life and
computational power only limited by the server you're hooked up to. It's the
perfect mobile device. Do the same thing for a laptop and I'm in paradise.

~~~
camillomiller
Wow, what a paradise. Total control made simple, that's what I see...

~~~
ivanca
Device good enough to do encryption?

~~~
aleksis
It's not like you can just sprinkle some encription there and it will be ok.

------
Tloewald
Assuming pCell works as advertised it's a _huge_ deal.

It allows you to cover a city in cells for insanely cheaper than current cell
technology and provide far, far better reception and bandwidth to far larger
numbers of customers AND it works with existing LTE gear while also affording
simpler, cheaper, and lighter-weight new gear and reducing power consumption
across the board. What's not to like?

I don't think anyone who has heard about pCell thinks it isn't a huge deal,
_if it works_.

One example of a major potential problem: how well does it track erratically
moving objects (e.g. most cell phones?), in built-up areas with lots of signal
reflection?

~~~
ajcarpy2005
The answer would largely depend on how large the focus area is or how fast the
signal quality degrades the further from the epicenter of the focal point that
the receiver is.

Maybe the system could apply road map info to fast-moving cell phones which it
can assume are in traffic. And this could help it predict possible future
locations of your device.

For much of the day the majority of devices in a given "cell" will be semi-
immobile at a desk or slowly moving when someone's walking.

~~~
pyre
What happens when someone turns on their phone on a plane? ;-P

~~~
ajcarpy2005
I think an on-board "repeater" would be the best solution. Of course, a high-
powered directional antenna would translate to less hopping between towers but
also increased costs to the carriers. Something like Google's Loon project
might have more coverage and work well with aircraft.

------
nardi
Steve Perlman always comes across as a snake oil salesman, but I didn't think
he could do OnLive either, and that technology works fantastically. As a
result, I'm pretty excited about pCell, even though it's being preceded by a
wave of marketing hype.

~~~
GFischer
It still hasn't made its way to my country, but it certainly is an interesting
service.

[http://en.wikipedia.org/wiki/OnLive](http://en.wikipedia.org/wiki/OnLive)

However, they did overpromise and under-deliver, but it's still very
impressive.

------
chacham15
As many positive things as I have heard about it I have one question: will we
ever actually see this as an actual product? I feel like I hear about so many
cool things which never come to fruition and I have a nagging feeling that
this might be one of them. Why? Because, as I've read, the companies would
need data centers to manage all of these connections. What interest do these
companies have to risk all of this money (a recurring cost, might I add) when
people probably wouldnt spend more for it? I dont profess to know, so can
someone who has actual information enlighten me?

~~~
XorNot
That isn't why stuff doesn't turn out. It usually has some problem or another
which is being assumed will be "solvable" by the time they release.

Never solve it? It's never released.

Alternatively, it does come out, but its gains are just evolutionary
improvements not revolutionary.

------
bprater
"With this technology, it's conceivable that 5G wireless could displace both
cable and DSL connections within a few years, as is claimed in the
presentation."

A few years?! This statement should give landline data providers, like Cox and
Comcast, some serious pause.

~~~
XorNot
Except for the part where you need an huge array of transmitters with backbone
bandwidth equal or greater the number of devices they may be serving
simultaneously.

In which case those companies just start doing fiber installs to wireless
stations, not houses, at roughly the same density.

~~~
cincinnatus
Or just piggyback an antenna into the hardware otherwise installed at each
consumer location. There was a theory almost a decade ago that Google would do
something like that on top of all the 'dark fiber' it was buying up at the
time.

------
tim333
The original Columbia presentation is actually pretty cool (
[https://news.ycombinator.com/item?id=7274288](https://news.ycombinator.com/item?id=7274288)
) I thought I'd mention it as it only got a couple of votes and sarky comments
at the time but having just watched it all I think it really look like a major
breakthrough, maybe the biggest one of the year and could be giving us 4k
video all over the place before long. One of the interesting things is it will
work with existing unlicensed spectrum, existing handsets and the backhaul can
be done with line of site links on rooftops so it can be rolled out pretty
much straight off - well they are talking a year or so.

~~~
DonGateley
Once you begin exploring the implications and the possible applications to
things other than communications it begins to look like possibly the biggest
breakthrough in history.

Only one in energy could surpass it.

------
mrfusion
I wonder if wireless power like this could be used to provide power for
launching spacecraft and this avoiding the tyranny of the rocket equation?

~~~
ars
This wouldn't help a rocket. For a rocket you should just aim a laser at it.

But you still need reaction mass, and pure energy doesn't work well for that.

------
higherpurpose
> Will it work for WiFi as well? It's protocol agnostic, so it could work in
> unlicensed spectrum as well. The issue is that you don't have complete
> control over all the other transmitters, so you can't coordinate them.

From the moment I heard of it, the first thing I thought about was: this could
make long range Wi-Fi possible (and therefore meshnets and carrier disruption
possible).

Seeing this tech being used by wireless carriers would be cool, but I really
want to see it (or something like it) being used in new mile long Wi-Fi
standards. Now the Wi-Fi Alliance only needs to make one for us.

Long range Wi-Fi could also make communication between self-driving cars much
more feasible (got your attention now, Google?) - although that presents a
pretty huge security risk, too, but I imagine the industry already wanted them
to be connected to the Internet, so it wouldn't be much worse.

------
redbad

        > Humans use <todo>.
    

Indeed.

------
hop
Wireless power transmission will change everything in hardware if someone can
pull it off. I'd bet Apple is waiting until they can do low power wirelessly
to launch their smart watch.

~~~
pazimzadeh
I doubt that Apple is waiting until wireless power to launch the smart watch,
but I agree that it will change everything. And it would make sense for Apple
to buy pCell. Of course Steve Perlman worked at Apple before.

[http://en.wikipedia.org/wiki/Steve_Perlman](http://en.wikipedia.org/wiki/Steve_Perlman)

~~~
ksec
Yes. I would much rather Apple spends billions on this than buy silly things
like Whatsapp. Article Point out C-RAN being expensive, surely Apple could
help or even host their own C-RAN? Since Apple were Originally interested in
MNVO anyway.

------
atrus
Don't you still have large power losses from the inverse square though?

~~~
bdcs
Nope (well, yes, as distance -> infinity)

Imagine three boats making waves such that the ripples constructively
interfere in some spots and destructively at others.

[http://en.wikipedia.org/wiki/Beamforming](http://en.wikipedia.org/wiki/Beamforming)

~~~
kastnerkyle
This will not magically be overcome by constructive interference - each beam
will still lose a significant amount of power as function of distance.

Higher frequency RF signals are fairly easy (especially V/UHF) to beamform
into a tight area, which can compensate for the loss, by focusing your power
in one direction instead of radially. You still lose power over distance as
the beam's energy spreads.

I don't believe they will just be able to blob a "networked" 60Hz transmission
into a 1cm area - I did not read the patent, but you may be able to do such a
thing by varying the phase to induce a 60Hz wave via beat frequencies between
transmitting signals, at ONLY the specified area.

Having the necessary +-1Hz resolution on a 2.4GHz carrier (especially one that
is not using a hardware connected, phase locked oscillator) may prove very
difficult if not impossible. I suspect they may try to use one of the lower
scientific bands around 900 or less MHz. HF is also a fairly unregulated
option, though tight beamforming may still be difficult. Perhaps a smart
application of null steering could create the necessary oscillation - I am
still working this out in a simulation.

If this method is correct, keeping everything tight enough to be within US
electrical standards will be difficult - there are specific regulations
related to in-band power, harmonics, frequency tolerances, etc. Regardless of
all that, this technology is pretty incredible and I look forward to
investigating it further!

~~~
marcosdumay
> This will not magically be overcome by constructive interference - each beam
> will still lose a significant amount of power as function of distance.

Well, yes, and no.

Each beam does "lose" energy compared to the theoretical amount it'd have
without interference.

But the power you can transmit into any area inside the cells coverage is
nearly constant, and you do not need to put that all extra energy your beans
are "losing" into the transmiters, just a tiny part of it (due to errors,
delays, object interference, etc).

------
raverbashing
This is a very nice explanation of not only pCell but of what modern
communication systems are like (802.11n has MIMO/diversity but also channel
estimation, etc)

People may find this interesting:
[http://en.wikipedia.org/wiki/Space–time_block_code](http://en.wikipedia.org/wiki/Space–time_block_code)

------
nardi
Is there any reason this same technology wouldn't work with light? Wouldn't
that be a phased light array?

~~~
marcosdumay
Electronics swithcing speed is the main botleneck to doing this with light.
And there are hard barriers that makes this kind of device impossible there.

But different devices with the same results are fair game.

------
kayoone
With seemingly unlimited mobile bandwidth and speed, the cloud gets a new
dimension too. Perlman has already proven that even the most demanding
applications, realtime games, work well in a streaming scenario even today.
With something like this, i could see my desktop in the cloud being accessible
from anywhere through a mobile thin client in my pocket. Hook up multiple
monitors/keyboard/mouse to it or just use the device screen itself, with
computing power only limited by the cloud provider. Technologies like OnLive
or PCoIP show thats its possible even today, all thats missing is the
infrastructure to support it and pCell could be the answer to that.

------
jessaustin
Linked paper:

[http://www.rearden.com/DIDO/DIDO_White_Paper_110727.pdf](http://www.rearden.com/DIDO/DIDO_White_Paper_110727.pdf)

------
neuromancer2701
While I think charging cell phones and Telsas is a problem, getting cheaper
than petrochemical energy is the key. So I have always thought that some sort
of space-based energy source was the solution but how do you get it back to
earth? 1000's of small solar cell beaming back energy concentrated at one
point would be a great solution. How much would this cost would be interesting
to find out?

------
jessaustin
Sort of reminiscent of ESWL, which breaks kidney stones, except in that case
they "aim" the sound waves with an elliptical waveguide.

------
bestrapperalive
At first I thought the technical challenges inherent in maintaining state for
a web of arbitrarily placed transmitters cooperatively targeting thousands of
moving devices would make this technology impractical for deployment in the
wild, but now I believe. pCell is going to be revolutionary. I can't wait to
get rid of my consoles and stream new, triple-A games over it.

------
fredgrott
USA Federal Communications and other gov agencies EU's for example wanted to
move towards telecomms spectrum being a commodity where the device hands off
to other carriers seamlessly to handle spectrum scarcity

pCell takes a different tact ..seems that the way to get telcomms to move
would be through government mandates tied ot say spectrum sales.

~~~
KaiserPro
pCell still requires a license to use out in the open. in the same way a
fempto cell does.

------
KaiserPro
Sorry, its just beamforming. Its not new, its just marketing.

its not all that different from having an 802.11n MIMO hotspot in your house.

~~~
KaiserPro
Infact its not all that different from femto cell base stations. You'll still
need a license to transmit on that frequency, and you still need a reliable
backhaul to dump the data on.

~~~
kristoffer
It's different from the MIMO employed in Wifi or "normal" LTE. They do not
create a cell per user, neither does a femto cell base station (it only
creates a small cell, not a personal cell).

------
frankus
I like to think of it as that conventional cellular is using a broadcast
medium for "narrowcast" communications.

If you put it that way it's obvious that we're currently Doing It Wrong,
provided there's a practical alternative. It also helps people get over their
reflexive "But Shannon says…" reaction.

------
mseri
A friend at CERN commented with this: " This is EXACTLY the same procedure
we're using to correct experimental data from distortions introduced by
detector effects (unfolding) -
[http://cds.cern.ch/record/1600778](http://cds.cern.ch/record/1600778) "

------
sarreph
I am pretty amazed by this technology and can't wait to learn more about it.
Just a note on the live demo with iPhones — aren't they likely to have
buffered the video they need before they were stacked, and therefore it
doesn't matter if their antenna connection was interrupted?

------
icoder
"Humans use <todo>" ? Perhaps attention?

~~~
tim333
Seems we use a variety of mechanisms, not fully understood -
[http://en.wikipedia.org/wiki/Cocktail_party_effect](http://en.wikipedia.org/wiki/Cocktail_party_effect)

------
3rd3
Another case of application might be localization.

------
DonGateley
Isn't this also instant and incorruptable net neutrality?

------
Dewie
Maybe it's just me, but that background on the left looks like some monitor
that had a seizure.

