Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

pCell, A Bold Scheme For Super-Fast Wireless Data

readwrite.com

Post reply on HN
Print view View original

21–28 of 28 posts

Re: pCell, A Bold Scheme For Super-Fast Wireless Data

#21

Post by KaiserPro »

Sigh

The biggest limiting factor of wireless is the lack of frequency in which to put you're data. Not interference.

pCell only works for small areas, what it does is essentially beamform a signal directly to the consumer (basically cupping your hands around your mouth when you shout at someone) I assume the "magic" comes from some sort of noise cancelling (yes just like the ear phones)

However in practice I assume they just use more than one beam former to create more than one beam.

It cannot be used for wide area systems, as the only reason this works is because its local. it provides bandwidth for one small area using the same frequency that the wider area is using.

Re: pCell, A Bold Scheme For Super-Fast Wireless Data

#22

Post by MrBuddyCasino »

KaiserPro wrote: post #21

Sigh The biggest limiting factor of wireless is the lack of frequency in which to put you're data. Not interference. pCell only works for small areas, what it does is essentially beamform a signal directly to the consumer (basically cupping your hands around your mouth when you shout at someone) I assume the "magic" comes from some sort of noise cancelling (yes just like the ear phones) However in practice I assume t…

Can you elaborate why it wouldn't work in a wide area setting? In a demonstration, they had a lot of cellphones on a desk, but not a matching number of pCell antennas, so it seems they can support many devices with a single (or at least much less) antenna.

Or do you mean to say that the beam forming is not going to work over large distances, so phones must be in close proximity to the antennas?

Re: pCell, A Bold Scheme For Super-Fast Wireless Data

#23

Post by noselasd »

MrBuddyCasino wrote: post #22
KaiserPro wrote: post #21

Sigh The biggest limiting factor of wireless is the lack of frequency in which to put you're data. Not interference. pCell only works for small areas, what it does is essentially beamform a signal directly to the consumer (basically cupping your hands around your mouth when you shout at someone) I assume the "magic" comes from some sort of noise cancelling (yes just like the ear phones) However in practice I assume t…

Can you elaborate why it wouldn't work in a wide area setting? In a demonstration, they had a lot of cellphones on a desk, but not a matching number of pCell antennas, so it seems they can support many devices with a single (or at least much less) antenna. Or do you mean to say that the beam forming is not going to work over large distances, so phones must be in close proximity to the antennas?

Just as a sidenote, LTE can also use beamforming, over rather large distances. How well implemented this is in current gear , I don't know.

Re: pCell, A Bold Scheme For Super-Fast Wireless Data

#24

Post by KaiserPro »

MrBuddyCasino wrote: post #22
KaiserPro wrote: post #21

Sigh The biggest limiting factor of wireless is the lack of frequency in which to put you're data. Not interference. pCell only works for small areas, what it does is essentially beamform a signal directly to the consumer (basically cupping your hands around your mouth when you shout at someone) I assume the "magic" comes from some sort of noise cancelling (yes just like the ear phones) However in practice I assume t…

Can you elaborate why it wouldn't work in a wide area setting? In a demonstration, they had a lot of cellphones on a desk, but not a matching number of pCell antennas, so it seems they can support many devices with a single (or at least much less) antenna. Or do you mean to say that the beam forming is not going to work over large distances, so phones must be in close proximity to the antennas?

the system will work over long distances, indeed he claims in the paper (with nothing to back it up, that paper is extra-ordinarily vague.)

However it wont increase bandwidth. (I should have been more precise) The only reason why people are interested in this is because it offers the idea of greater bandwidth.

The way they increase bandwidth is effectively partitioning the local airspace off from the wider world. Each cell (be it TV, phone or $other) can deliver x bandwith.

The bigger the area covered by the cell, the less bandwidth per unit of volume. (conversely the smaller the more bandwidth per volume)

This is before we start doing clever things like spread spectrum or account for signal loss/noise/shannon's law

This is pretty much snake oil. Its beam forming with a marketing budget. There is nothing in that paper that suggests otherwise

Re: pCell, A Bold Scheme For Super-Fast Wireless Data

#25

Post by 3rd3 »

KaiserPro wrote: post #21

Sigh The biggest limiting factor of wireless is the lack of frequency in which to put you're data. Not interference. pCell only works for small areas, what it does is essentially beamform a signal directly to the consumer (basically cupping your hands around your mouth when you shout at someone) I assume the "magic" comes from some sort of noise cancelling (yes just like the ear phones) However in practice I assume t…

> The biggest limiting factor of wireless is the lack of frequency in which to put you're data. Not interference.

Isn’t the idea to send data to multiple devices at the same frequency simultaneously? Signal interferences are prevented by clever timing of the three senders, namely by creating interferences that add up to noise everywhere except for a small volume that hopefully contains the receiving device.

Re: pCell, A Bold Scheme For Super-Fast Wireless Data

#26

Post by KaiserPro »

3rd3 wrote: post #25
KaiserPro wrote: post #21

Sigh The biggest limiting factor of wireless is the lack of frequency in which to put you're data. Not interference. pCell only works for small areas, what it does is essentially beamform a signal directly to the consumer (basically cupping your hands around your mouth when you shout at someone) I assume the "magic" comes from some sort of noise cancelling (yes just like the ear phones) However in practice I assume t…

> The biggest limiting factor of wireless is the lack of frequency in which to put you're data. Not interference. Isn’t the idea to send data to multiple devices at the same frequency simultaneously? Signal interferences are prevented by clever timing of the three senders, namely by creating interferences that add up to noise everywhere except for a small volume that hopefully contains the receiving device.

Thats spread spectrum. Which is what wifi uses. each device raises the noise floor, until you can't add more devices.

Re: pCell, A Bold Scheme For Super-Fast Wireless Data

#27

Post by vardump »

KaiserPro wrote: post #21

Sigh The biggest limiting factor of wireless is the lack of frequency in which to put you're data. Not interference. pCell only works for small areas, what it does is essentially beamform a signal directly to the consumer (basically cupping your hands around your mouth when you shout at someone) I assume the "magic" comes from some sort of noise cancelling (yes just like the ear phones) However in practice I assume t…

Interference is pretty much the only the limiting factor locally for information capacity for any given frequency band. What Artemis is doing is "spacetime" coding signal in such a way constructive interference forms at desired locations.

Part of the "magic" apparently comes from return channel analysis, nothing at all like noise cancelling earphones. This doesn't try to cancel existing interference in any way.

This is a superset of beamforming, a more generic solution with arbitrary positioning. Nothing is ever completely new.

I'm not sure what you mean by wide area systems, but I don't see any reason why the range can't be even hundreds of kilometers, limited just by line of sight and signal attenuation. Roundtrip delay might affect doppler compensation at greater distances.

Re: pCell, A Bold Scheme For Super-Fast Wireless Data

#28

Post by rasz_pl »

kristoffer wrote: post #20
rasz_pl wrote: post #18

secong gen 802.11ac will do this too, MU-MIMO will use beam forming to send up to 4 streams to up to four clients simultanously. http://chimera.labs.oreilly.com/books/1234000001739/ch04.htm...

It is not the same thing. 11ac does normal beam forming not network/distributed MIMO.

secong gen will be distributed
Post reply on HN