Beta
×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

New 'pCell' Technology Could Bring Next Generation Speeds To 4G Networks

Unknown Lamer posted about 8 months ago | from the spherical-harmonics dept.

Wireless Networking 120

An anonymous reader writes in about a possible game changer in wireless technology that embraces interference with great results: "It's one of those elegant inventions that only surface maybe once a decade. If it works at scale, according to IEEE Spectrum, it could 'radically change the way wireless networks operate, essentially replacing today's congested cellular systems with an entirely new architecture that combines signals from multiple distributed antennas to create a tiny pocket of reception around every wireless device.' This scheme could allow each device to use the full bandwidth of spectrum available to the network, which would 'eliminate network congestion and provide faster, more reliable data connections.' And the best part? It's compatible with 4G LTE phones, which means it could be deployed today." The idea is that an array of dumb antennas are deployed and a very powerful cluster computes signals that are sent from all of them which then appear to be a single coherent signal to only a single device. There's a short paper on the Distributed In Distributed Out technique, but it is a bit light on the mathematical details.

Sorry! There are no comments related to the filter you selected.

Next Generation speeds (5, Funny)

rossdee (243626) | about 8 months ago | (#46288205)

So like Warp 9.5 then?

Re:Next Generation speeds (2)

tech.kyle (2800087) | about 8 months ago | (#46288243)

Logged in just in case I had mod points, but alas I have none. I tried.

Re:Next Generation speeds (2)

funwithBSD (245349) | about 8 months ago | (#46288495)

This space ship goes to 11, man!

it's "steerable null" with the antennas spread out (1)

Ungrounded Lightning (62228) | about 8 months ago | (#46290269)

As I read this, DIDO is exactly "steerable null" with the antennas spread out.

Of course the antennas are spread out VERY FAR APART, as in to multiple sites using a central computation of the I/Q signal and synchronizing separate local oscillators at the remote sites. This results in "bubbles around", rather than "beams at", those cellpphones that are in among the antennas.

Re:Next Generation speeds (1)

Anonymous Coward | about 8 months ago | (#46290579)

So like Warp 9.5 then?

No, like actual 4G speeds!

Re:Next Generation speeds (0)

Anonymous Coward | about 8 months ago | (#46291553)

>"It's one of those elegant inventions that only surface maybe once a decade."

yeah, like the 1950's; this is stochastic reinforcement of the signal. they've been using this technology for decades on space probes.

Don't hold your breath (2, Interesting)

Anonymous Coward | about 8 months ago | (#46288263)

The big wireless operators haven't even finished rolling out (let alone paying for) their 4G rollout, and somebody thinks they're going to scrap it all and spend billions more rolling out new technology? O-K....

Re:Don't hold your breath (3)

pepty (1976012) | about 8 months ago | (#46288443)

The operator would then need to install radio antennas where its customers are located, such as in homes, businesses, and city streets. Although these access points might look like small cells (Artemis’s, pictured below, are about the size of a hat box), they’re unlike ordinary base stations. “They’re dumb devices,” Perlman says, serving merely as waypoints for relaying and deciphering signals. Each one could be placed anywhere that’s convenient and would link back to the data center through a fiber or wireless line-of-site Internet connection.

Doesn't sound expensive at all - for the operator. They'll just install pCell hardware for the customers that want it in their location at 200% of cost.

RE: Don't hold your breath (1)

Anonymous Coward | about 8 months ago | (#46288477)

Actually what's cool about this approach is that the startup company behind it has made the new technology compatible with existing LTE (4G) networks. So operators wouldn't need to swap out the old for the new all at once, as they did to make the leap from 3G to 4G. Rather, they could just use pCell where they need to, such as in busy urban centers, and LTE users wouldn't know the difference (except for the suddenly good reception).

Re: Don't hold your breath (4, Interesting)

rudy_wayne (414635) | about 8 months ago | (#46288645)

Actually what's cool about this approach is that the startup company behind it has made the new technology compatible with existing LTE (4G) networks. So operators wouldn't need to swap out the old for the new all at once, as they did to make the leap from 3G to 4G. Rather, they could just use pCell where they need to, such as in busy urban centers, and LTE users wouldn't know the difference (except for the suddenly good reception).

According to TFA (which of course no one read):

"“Demand for spectrum has outpaced our ability to innovate,” says Perlman. The reason isn’t for a lack of ideas. The wireless industry is pursuing plenty of them, including small cells, millimeter-wave spectrum, fancy interference coordination, and multiple antenna schemes such as MIMO. But Perlman thinks many of these fixes are just clever kludges for an outdated system. The real bottleneck, he argues, is the fundamental design of the cellular network. “There is no solution if you stick with cells,” he says.

Even though it is technically compatible with 4G you still have to deploy millions of new antennas. He may have invented the greatest wireless technology ever, but it's dead on arrival due to cost.

Not quite (1)

Anonymous Coward | about 8 months ago | (#46288821)

Actually, you wouldn't have to deploy millions. You could deploy a couple doze in a ball park, for example, and get a good boost in capacity. And operators are already investing in infrastructure like this, such as small cells to try to cover places like ball parks. Infrastructure-wise, pCell wouldn't present any more challenges than small cells. In fact, they might even be a bit cheaper and simpler because they can be installed anywhere in a given area. You don't want one on your roof, but maybe your neighbor doesn't mind.

Re: Don't hold your breath (1)

Ungrounded Lightning (62228) | about 8 months ago | (#46288889)

Even though it is technically compatible with 4G you still have to deploy millions of new antennas. He may have invented the greatest wireless technology ever, but it's dead on arrival due to cost.

Actually it may be cheaper than buying more spectrum and putting in more equipment at the cell sites, since it doen't involve buying more spectrum.

It DOES involve putting in more cells. But far fewer than you'd need to put in to subdivide the cells, in the normal cellular paradigm, to get the same amount of bandwidth reuse multiplication.

Also: You can start it by putting the new computation into just the existing cells and handle more connections than with the old scheme. (After that it's add more cells in the customary maner, with more bang per buck.) If replacing/upgrading the existing cells gives you more

Re: Don't hold your breath, full post. (2)

Ungrounded Lightning (62228) | about 8 months ago | (#46288975)

(I'm not used to the tuchpad on my new laptop and seem to have actidentally posted mid-edit. Reposting the full version.)

Even though it is technically compatible with 4G you still have to deploy millions of new antennas. He may have invented the greatest wireless technology ever, but it's dead on arrival due to cost.

Actually it may be cheaper than buying more spectrum and putting in more equipment at the cell sites, since it doen't involve buying more spectrum.

It DOES involve putting in more cells. But far fewer than you'd need to put in to subdivide the cells, in the normal cellular paradigm, to get the same amount of bandwidth reuse multiplication.

Also: You can bootstrap it by putting the new computation into just the existing cells, letting you handle more connections than with the old scheme. (After that it's add more cells in the customary maner, with more bang per buck.) Not only that, you only need to do it in areas where you're already running out of base station capacity and starting to suffer service level problems due to oversubscription/congetioin. If replacing/upgrading the equipment in existing cells gives you more additional connections per buck than the alternatives, there's no adoption cliff at all.

Re: Don't hold your breath, full post. (2)

Jane Q. Public (1010737) | about 8 months ago | (#46289115)

"It DOES involve putting in more cells. But far fewer than you'd need to put in to subdivide the cells, in the normal cellular paradigm, to get the same amount of bandwidth reuse multiplication."

From the descriptions, it sounds like it's basically phased-array technology, which has been in use in radar systems for decades. Of course this is a vastly different application and involves active feedback, so while the physics might be the same the rest isn't.

This was actually done for public wi-fi many years ago. It worked, but it turned out the cost was not much if at all lower than just coverage with simpler hotspots. But again: this is a different application and these are different circumstances. It might turn out better.

Re: Don't hold your breath, full post. (0)

Anonymous Coward | about 8 months ago | (#46290003)

(I'm not used to the tuchpad on my new laptop and seem to have actidentally posted mid-edit.

The cure for this is to disable the trackpad (Alt+F7 on many laptops) and use the arrow keys or a mouse. WFM.

Re: Don't hold your breath, full post. (0)

Anonymous Coward | about 8 months ago | (#46290013)

The benefit is you really don't need more cell sites, this is basically a phased array, and you can install a hundred cells on one cell tower to get a 100x increase in performance for the area around it (in a perfect world, realistically it's less). And in reality this would probably be implemented by just replacing the existing antennas with a 100 element antenna. Since this is compatible with existing tech you don't have to do a nation wide rollout, you don't need to get customers to buy new phones, and you don't need to go through the process of installing more towers with their associated rent and people fighting your plans.

So I can see this happening because they can get a 100x performance increase in very densely populated areas (like nyc) by upgrading relatively few towers. Being able to claim 100x faster Internet in the most densely populated areas means a lot, and it can be well worth the money.

Re: Don't hold your breath (2)

NoImNotNineVolt (832851) | about 8 months ago | (#46289133)

Much like 4G never took off because not only did it require the deployment of millions of new antennas but also hundreds of millions of new phones.

Wait, what? 4G wasn't dead on arrival due to cost?

The moral of today's story is that new infrastructure is periodically rolled out, and the cost of such rollouts doesn't prevent them from occurring. Additionally, there are considerably fewer cell towers than there are cell phones.

Re: Don't hold your breath (2)

JoeMerchant (803320) | about 8 months ago | (#46289407)

What does one antenna cost?

Can I put one on the pole outside my bedroom window?

If I could get reliable cell coverage in my home, I'd pay $200-300 for that.

Re: Don't hold your breath (0)

Anonymous Coward | about 8 months ago | (#46290039)

That's not how it works. What this does is defeat interference by splitting the signal with crazy math and a big computer. Your speed won't increase, but you won't get timeouts and buffering and dropped calls from interference.

Re: Don't hold your breath (1)

schnell (163007) | about 8 months ago | (#46290609)

If I could get reliable cell coverage in my home, I'd pay $200-300 for that

You can already do that today, that's what femtocells are all about. AT&T version here [att.com] , Verizon version here [verizonwireless.com] . I'm sure most other carriers have similar options... no fancy new technologies required.

Re: Don't hold your breath (1)

cduffy (652) | about 8 months ago | (#46290801)

If I could get reliable cell coverage in my home, I'd pay $200-300 for that.

Switch to Republic [republicwireless.com] , and your voice, SMS and MMS all run over your WiFi, and hand off to Sprint's cell network when out-of-range.

Which gives you reliable coverage in your home, and a deep discount from a typical carrier's monthly rates.

-- Satisfied customer. (Well, moderately satisfied -- Sprint's 4G coverage in Austin was iffy until they got a bunch of tower repairs done; that they let it go for such a long time didn't speak well).

Re: Don't hold your breath (1)

JoeMerchant (803320) | about 8 months ago | (#46291183)

I have T-Mobile with WiFi calling, it's a good thing, but not as "rock solid" as you might expect it to be.

Re: Don't hold your breath (1)

cduffy (652) | about 8 months ago | (#46291281)

I switched over from T-Mo. Republic's implementation is considerably better, particularly the handoff support.

Re:Don't hold your breath (0)

Anonymous Coward | about 8 months ago | (#46289889)

Sprint did it. They rolled out WiMax before doing a 180, scraping it, and rolling out LTE.

What about recieve? (4, Interesting)

ThatAblaze (1723456) | about 8 months ago | (#46288275)

Being able to transmit more strongly is all well and good, but the phone can only send using so much juice. If you turn up the power of the phone too much it will just get in the way of other phones' transmission like they do now.

Still, half of a solution is better than nothing, I suppose.

Re:What about recieve? (1)

CodeReign (2426810) | about 8 months ago | (#46288375)

I doubt it, they'd calculate latency from tower to tower and analyze the data on the fly to pull out more accurate results. (that's how I read it anyway)

Re:What about recieve? (0)

Anonymous Coward | about 8 months ago | (#46291991)

If my phone is closer to your phone than the nearest tower the signal from your phone will reach my phone and interfere with it before it reaches the cell tower to do any computations. This will interfere with the download speed on my phone being that the cell phone tower can't predict future signals from your phone to send the required compensation signals to my phone on time being that the signal from your phone reaches my phone before it reaches the cell phone tower.

Re:What about recieve? (0)

Anonymous Coward | about 8 months ago | (#46292053)

(same person)

now if every phone were equipped with multiple well calibrated antennas the phone itself could do its own signal processing based on signal differences from different positions and possibly yield much better bandwidth.

Re:What about recieve? (1)

Immerman (2627577) | about 8 months ago | (#46288519)

I suspect that the technique is reversible - your phone signal will interfere with all the others, but by analyzing the composite signals received by all the antennas in range the signals from individual phones can be reconstructed.

Re:What about recieve? (1)

Ungrounded Lightning (62228) | about 8 months ago | (#46289925)

Precisely. The equivalent computation is done in the receive pipe, so the base station system "hears" from each bubble separately, as well as "speaking" separately to each.

In fact it has to be done this way, or you'd only get the bandwidth multiplication in the outbound direction and the inbound direction would be sharing the bandwdith. (Fortunately the transmit and receive pathways are exactly duals of each other.)

Re:What about recieve? (1)

Impy the Impiuos Imp (442658) | about 8 months ago | (#46288533)

Most phone use is download. Unless you're trying to stream live video up from your phone (or run a freaking server, please) you don't really need it. Also it's just one broadcast point -- this seems to need multiple to craft some kind of partial waves that stack up only in a very limited region of your actual phone location, with all that partial crap just cresting through each other for everyone else. Think a whisper gallery where the walls are computer-driven antennae controlling pseudo-reflections.

Skype and FaceTime (2)

tepples (727027) | about 8 months ago | (#46288937)

Unless you're trying to stream live video up from your phone [...] you don't really need it.

What do you think Skype and FaceTime are?

Re:What about recieve? (1)

egcagrac0 (1410377) | about 8 months ago | (#46289243)

Most phone use is download.

AFAIK, most "download" protocols are bidirectional - there's a confirmation that each block was properly received. (TCP vs UDP)

The portable device may not need to transmit much, but there's likely a string of "Yup, Checksum OK"'s getting transmitted, even when "just" streaming a video.

Re:What about recieve? (0)

Anonymous Coward | about 8 months ago | (#46288627)

It's symmetrical. If you have very precise time synchonization of a set of antennas and can get the signal from those antennas, you can recombine the signals (time shift, amplify etc.) to artificially focus on emitters in a specific area.
I believe MIMO wifi antennas do that but with a couple antennas that are very close together.
Here, it's a matter of using antennas that are possibly hundreds of feet apart.
And it can work for both emission and transmission.
Neat.

Re:What about recieve? (2)

Solandri (704621) | about 8 months ago | (#46289855)

It can be used both ways. What they're describing is basically tomography [wikipedia.org] . By analyzing the signal recorded from different locations, you can construct a 2D or 3D representation of signal strength, thus allowing you to pin down a specific phone's transmissions based on location (rather than frequency or code or time - what's used for OFDMA, CDMA, and TDMA respectively). The reverse process would involve modulating the transmission strength and phase from multiple towers in a synchronized fashion so that the peak signal strength in a 2D or 3D field happens to be where that phone is located. It also frees you from the Shannon limit on bandwidth [wikipedia.org] because the amount of channel noise is now location-dependent, rather than solely being frequency-, code- or time-dependent. Very clever work.

Re:What about recieve? (0)

Anonymous Coward | about 8 months ago | (#46289933)

Exactly.

This is the type of thing that some people have been saying has been possible for almost two decades, such as David P. Reed. The Shannon channel capacity is not the limit to radio bandwidth in the aggregate; it's computational capacity. And moving computation to a super computer means your aggregate bandwidth limits are enormous.

Phased array. (4, Interesting)

harrkev (623093) | about 8 months ago | (#46288279)

It sounds like a logical extension of phased-array technology. Or, sort of how they do radiation cancer treatment with dozens of weak beams converging on one spot.

However, in order to get this to work well, you need the transmitted signal to be phased-aligned to within an appreciable fraction of a wavelength. Since we are around a gigahertz, that means that the phase of the carrier should be accurate to within a couple hundred picoseconds, max. How you maintain this accuracy over multiple cell sites confuses me. Of course, this is all a wild-ass guess on how the technology works.

Re:Phased array. (2, Informative)

Anonymous Coward | about 8 months ago | (#46288305)

And, even if it only appears as a proper signal at one point, it's going to raise the noise floor for everyone.

Re:Phased array. (4, Informative)

harrkev (623093) | about 8 months ago | (#46288563)

True about the noise floor.. However, if this works as advertised, the net gain in one spot should overcome the generalized increase in the noise. For example, a 10 dB gain in local signal would be well worth even a 6 dB gain in overall noise.

Re:Phased array. (2)

Chalnoth (1334923) | about 8 months ago | (#46289125)

This isn't necessary at all. It's entirely possible for there to only be an appreciable amount of EM radiation at the desired destination. So you can actually lower the noise floor for everybody else versus today's systems. In fact, because the destination signals are spatially-localized, your only limitation on how many devices you can put on the same network is the size of the localized waveform.

The primary concern I have is how they're going to accurately determine the position, and how they're going to accurately factor in obstacles such as buildings and especially vehicles in computing the required EM waveform. I suppose it might work if they make use of some sort of feedback mechanism that continuously updates the waveform based upon information from the phone about the signals it is receiving, but those updates would have to be extremely fast for it to work in a moving vehicle.

Re:Phased array. (1)

strstr (539330) | about 8 months ago | (#46288507)

Directed-energy is another thing. Say the antennas become focused, directing energy right to the devices, and separating the signal from each device by creating a higher resolution sensor for imaging the surrounding landscape..

Ideally the phones would have a similar mechanism but current 4G LTE phones do not. they are omnidirectional and broadcast noise in all directions, even if the antenna system is at a specific location.

the current system is a waste of resources and terrible design, really antiquated ..

Re:Phased array (1)

Ungrounded Lightning (62228) | about 8 months ago | (#46289285)

Ideally the phones would have a similar mechanism but current 4G LTE phones do not. they are omnidirectional and broadcast noise in all directions, even if the antenna system is at a specific location.

That doesn't matter. You just do the equivalent computation on the returned signal. You "listen" separately to the individual bubbles, just as you send separately to them.

So you only need to do it at one end - the one where coordinating and combining the signals is practical.

Re:Phased array. (1)

ThatAblaze (1723456) | about 8 months ago | (#46288549)

Good point. Time synchronization would be something of a hurdle. However it seems like a solve-able problem since we ARE talking about a device that can send and receive signals wirelessly in order to synchronize. Guess and check works pretty well for this, i.e. packet 1: "I think you are receiving this at 1:17:36.455667" packet 2 "it was 0.0003 seconds fast."

Re:Phased array. (1)

Immerman (2627577) | about 8 months ago | (#46288873)

Yes it does.

Well, if you've got sufficient precision then continuous synchronization can probably be done using known signals received by all antennas - a few calibration antennas perhaps, or listening in on GPS signals. Of course that assumes that resynchronization is necessary, and it may well not be: The signal delay between headquarters and the various antennas can be constant if so designed, and the antennas can be made sufficiently non-mobile without too much trouble, though those tall cell towers that sway in the wind will have to go. After that it's simply a matter of actually measuring all the delays with sufficient precision, and that shouldn't be too hard, especially if they're allowed a brief post-deployment window to transmit an calibration signal strong enough to be received by all the antennas

I would think the greater challenge would be calibrating for all the attenuation - unless I misunderstand phased-array technology, a nice thick wall that blocks the signal from one or two antennas is going to severely disrupt a phased array system that assumes only position-based changes in a clear air signal. And calibrating for the attenuation caused by every single wall in every building (which may well be necessary if you're trying to isolate 1000+ phone signals in one building) is going to be a real challenge - not to mention the continuously changing attenuation from large vehicles. Perhaps sufficient redundancy in the array could make the issue solvable, but I wouldn't want to be the one who has to write the software that reconstructs tens of thousands of phone signals from a phased array where individual antennas are perpetually losing individual source signals pseudo-randomly.

Re:Phased array. (1)

Ungrounded Lightning (62228) | about 8 months ago | (#46290023)

It sounds like a logical extension of phased-array technology. Or, sort of how they do radiation cancer treatment with dozens of weak beams converging on one spot.

The former. Phased array is coherent (phase between sources is controlled and signals can cancel). Reverse-tomography radiation treatment is incoherent (phase is uncontrolled and energy only adds - but you make it strong in one place and as weak as practical elsewhere, or especially weak at other particularly radiation-sensitive sites.)

(I'd love to see a holographic tomography system, using, say, coherent x-rays. gamma rays, or even tunneling charged particles. B-) The closest I've heard of is the muon beam, where the muons decay at a particular distance from the accellerator that makes them, making a "bright star" spot on the end of a "dim rod")

Re:Phased array. (1)

harrkev (623093) | about 8 months ago | (#46290189)

It is sort of a combination of the two... Phased array usually has one source (well, dozens of sources, but clumped together). Radiation treatment involves multiple sources, as this does. But you do still need to control the phase. It is really sort of a combination of the two.

delay lines (1)

epine (68316) | about 8 months ago | (#46290377)

However, in order to get this to work well, you need the transmitted signal to be phased-aligned to within an appreciable fraction of a wavelength. ... Since we are around a gigahertz, that means that the phase of the carrier should be accurate to within a couple hundred picoseconds, max.

Micrel SY89295U
Programmable delay range: 3.2 ns to 14.8 ns in 10 ps increments in 2^10 discrete steps.
160 ps rise/fall, less than 2 ps RMS cycle-to-cycle jitter.

That gives you a spatial resolution of about 3 mm within a 3 m pixel on the fine delay; more if you also introduce a coarse delay line (in 10 ns increments). I think the Xilinx DCM gives a step delay on the order of 10 ps in 1024 discrete steps. You've now got 3 mm steps out to 3 km. Note that the linearity of these delay lines is not perfect, so there's some art to it (it's not a simple two-digit number in base 1000), but the worst case step remains small. You might use two DCMs in series plus the CML Micrel to ensure uniform coverage (one Spartan 3E has four DCMs IIRC). Actually, for a multi-channel base station, you'd need to fabricate an ASIC with a very large number of programmable delay lines, as I imagined it before RingTFA.

If the phone is 150 m away from a cell transmitter, you can set up a ping pong ping loop with a round-trip frequency of 1 MHz, where each end bats the pulse back as fast as possible.

Imagine the phone sends out a coloured packet and two or more base station pong it back. The phone can ping back on the first received response, or the last, or the n'th response in between. The fastest paths need to be artificially delayed until all paths are equal time. (With multi-pathing, the radio might be able to detect and measure more than one path length per base station.)

It would take long to achieve the coarse lock-on. Then it needs to maintained during motion of the mobile end, plus changes in atmospheric conditions, or sway in the buildings you're bouncing off of, if you've used the loudest path instead of the quickest path. The timing fabric is quite doable. The delay line can be anywhere in the ping pong circuit. The non-radio portions would ideally use fibre as copper has a temperature-variable c that adds up quick in the ps regime where lengths of 100 m are involved.

I can totally see this working, though radio systems at this level are astrobuck black magic.

The software-defined LTE phased array waveform simulation would be an interesting computational problem. They probably do the time extraction with DSP rather than actual delay lines. I'm wondering how much the upstream channel borks total throughput.

Maybe this is the Netflix special. Agility is always the last crow.

Re:delay lines (1)

epine (68316) | about 8 months ago | (#46290431)

In my post above: ... wouldn't take long ...

Fingers too fast, or delay line from the Chomskian trace badly programmed.

Speech Errors as Linguistic Evidence [google.ca]

Good (0)

The Cat (19816) | about 8 months ago | (#46288281)

Mobile phone reception is atrociously bad considering the prices mobile companies demand.

In 1960, a phone call could be placed from any point in the United States to any other point in the United States and the sound quality would be consistently good.

Now you can't make a call down the street without it sounding like the person at the other end is being beamed through an interdimensional time warp.

Re:Good (2)

harrkev (623093) | about 8 months ago | (#46288351)

Well, I can't comment on the prices, but several things go into the voice quality...

1) Voice quality is actually pretty good if you stick to a POTS land-line. Back in the 60's, everything was analog, so the noise added up.

2) Cell phone reception certainly can be bad, but back in the 80's when cell phones were invented, you had giant phones that could pump out a couple of watts because you had a large antenna and large batteries. Modern phones have tiny batteries and tinier antennas. This is partially compensated by a better noise floor on the cell-site receivers, but there ain't no such thing as magic.

3) Old analog cell phones transmitted actual analog voice at full bandwidth. While a waste of bandwidth, it sounded pretty good. Modern phones compress the heck out of your voice before sending it. The last time I checked, it was using some variant of CELP, which sounds fairly good, but far from perfect.

4) Data is now packetized (part of the compression). If you loose any part of the packet, you loose about 1/4 second of voice or so. In analog phones, you would hear a pop. or 1/10 second of silence.

overlyPedanticPedant (2)

MondoGordo (2277808) | about 8 months ago | (#46288461)

I think you meant "lose" rather than "loose" you can blame it on autocorrect if you want ....

Re:overlyPedanticPedant (-1)

Anonymous Coward | about 8 months ago | (#46288629)

I think you meant "lose" rather than "loose"

you can blame it on autocorrect if you want ....

You are going to find yourself on the wrong side of history sir. The word "lose" is quickly falling out of fashion and being replaced by "loose". It won't be long before webster makes it official. The word "loose" will have two meanings, and "lose" will be elminated from the language entirely. English is constatnly changing. When people stopped using words like "Ye" or "thou" back in the day, people like you probably complained.

Re:overlyPedanticPedant (1)

Anonymous Coward | about 8 months ago | (#46290111)

"Loose" already has 2 meanings.

The verbs "to loose" and "to lose" are pronounced differently and have rather different meanings.

I'll keep speaking and writing English, and you can continue making shit up to make yourself feel better, since you can't be troubled to do so.

Re:overlyPedanticPedant (-1)

Anonymous Coward | about 8 months ago | (#46290237)

"Loose" already has 2 meanings.

The verbs "to loose" and "to lose" are pronounced differently and have rather different meanings.

I'll keep speaking and writing English, and you can continue making shit up to make yourself feel better, since you can't be troubled to do so.

What is wrong with trying to improve the language? Should we just keep doing things the way they have always been done for the sake of it? Why the hell do we still hang onto the silent "k" in knife or knight from Old English? Can we just drop the "k" already as nobody is using it? It is people like you that insist on clinging to the past that prevent the language from getting more sane and logical.

Re:Good (1)

MobyDisk (75490) | about 8 months ago | (#46288701)

In 1960, a phone call could be placed from any point in the United States that had a 10 lb telephone hard-wired to it to any other point in the United States that had a 10 lb telephone hard-wired to it and the sound quality would be consistently good.

FTFY.

Re:Good (1)

mwehle (2491950) | about 8 months ago | (#46288809)

Yeah, that was my reaction too - I remember in the 60s and 70s "finding a phone" was a recurrent task, and the idea that one could call from "any" point was the thing of science fiction.

Re:Good (1)

camperdave (969942) | about 8 months ago | (#46289349)

In 1960, a phone call could be placed from any point in the United States that had a 10 lb telephone hard-wired to it to any other point in the United States that had a 10 lb telephone hard-wired to it and the sound quality would be consistently good.

FTFY.

... and the sound quality would be consistent. A lot depended on where the source and destination were, and the trunk quality between the various stations, but once you had a circuit, you had a circuit for the entire duration of the call, even if there was crosstalk, line noise, or what have you.

Re:Good (1)

drinkypoo (153816) | about 8 months ago | (#46289631)

... and the sound quality would be consistent. A lot depended on where the source and destination were, and the trunk quality between the various stations, but once you had a circuit, you had a circuit

... until you were cut off unexpectedly and found yourself listening to either a dial tone or a busy signal depending on the era.

Re:Good (1)

NatasRevol (731260) | about 8 months ago | (#46289427)

It took me 3 reads to see that he wasn't talking about cell phone.

Then I was like WTF?

Re:Good (1)

jeffmeden (135043) | about 8 months ago | (#46289079)

Mobile phone reception is atrociously bad considering the prices mobile companies demand.

In 1960, a phone call could be placed from any point in the United States to any other point in the United States and the sound quality would be consistently good.

Now you can't make a call down the street without it sounding like the person at the other end is being beamed through an interdimensional time warp.

Your definition of "any point in the United States" leaves a lot to be desired, but yes cell phones do compromise sound quality for low power consumption and usable signal.

DIDO ... just more MIMO? (1)

darronb (217897) | about 8 months ago | (#46288287)

Sounds like more of the same beamforming they've done for years, just more of it spread further apart.

So DIDO, distributed in distributed out... sounds like MIMO with more antennas, more distance between them (surrounding the targets, even)

I'm not sure why this isn't an obvious extension of MIMO. Harder to do, sure... and cool that it's coming... but obvious in concept.

Re:DIDO ... just more MIMO? (0)

Anonymous Coward | about 8 months ago | (#46288371)

It's actually a phased array technique. However, it has significant challenges with timing, since now motion of the antenna becomes a huge factor (more than 1/4 wavelength in position uncertainty shits out the effect of an individual element. This will be fine for antennas that are solidly connected to buildings in the lower bandwidths, but useless for 1800/1900 MHz on towers. Yes, they do move that much.

Re:DIDO ... just more MIMO? (1)

camperdave (969942) | about 8 months ago | (#46289367)

It's actually a phased array technique. However, it has significant challenges with timing, since now motion of the antenna becomes a huge factor (more than 1/4 wavelength in position uncertainty shits out the effect of an individual element. This will be fine for antennas that are solidly connected to buildings in the lower bandwidths, but useless for 1800/1900 MHz on towers. Yes, they do move that much.

Since this is likely to be a self-healing/self-adjusting network, I would imagine it would depend more on how quickly the antennas move rather than the fact that they do move.

Re:DIDO ... just more MIMO? (1)

Ungrounded Lightning (62228) | about 8 months ago | (#46289701)

It's actually a phased array technique.

As is MIMO (which is more general but includes phased array as a special case when the number of antennas at one end of the link is one.)

However, it has significant challenges with timing, since now motion of the antenna becomes a huge factor (more than 1/4 wavelength in position uncertainty shits out the effect of an individual element.

At the customer end this is not a problem, since it's the difference of the paths to the various base antennas that matters. An easier way to visualize it is to notice that the technique creates bubbles where essentially only the desired channel is received (and from which the transmitted signal is the only one of the subscribers received in the corresponding uplink channel after the DIDO processing). As you move away from the middle of the bubble the signals to the other subscribers begin to rise from the noise floor - but that's slow enough that the DIDO computation can be updated. (I suspect that for phones in vehicles the "DIDO data center" will need to estimate the speed and direction of the target (i.e. the way the phases of the signals are changing) and continuously update the computation, interpolating between actual measurements.

Changes to the relative position of the base antennas is much more significant:

This will be fine for antennas that are solidly connected to buildings in the lower bandwidths, but useless for 1800/1900 MHz on towers. Yes, they do move that much.

But they're massive and move slowly - far below an audio rate (in essentially two dimensions, i.e. a subsonic stereo signal). So this can be included in the computation.

You'll want to feed the measurements of the antenna motion back to the DIDO center, which would be very low bandwidth. Doing the computation at the antenna site would require broadening the pipe to/from it to be as wide as the sum of the max bandwidth to ALL the subscribers rather than the max bandwidth to one. You'll also want to estimate the motion a little bit ahead on the base-to-subscriber side, to tune out the measurement/transmission delay of the antenna position info going to the cener and the computed waveforms going to the antenna.

Actually, no. (0)

Anonymous Coward | about 8 months ago | (#46288719)

The only similarity between DIDO and MIMO, as far as I understand it, is that they both use multiple antennas to send and receive separate data streams simultaneously. But their signal processing schemes are very different. In broad strokes: DIDO does the signal processing (matrix math) on the transmitter side while MIMO does it on the receiver side. MIMO has some great potential, but that's one of the big problems with it: In order for your phone to use MIMO, it has to be able to house multiple antennas (which is tough simply for lack of space)--or share signal information with neighboring phones (distributed MIMO)--and it has to be able to do some fairly sophisticated calculations (which drains your battery). That's why DIDO would be pretty cool if it works: Your phone would only need 1 antenna and all it would have to do would be decode the signal (no time-frequency scheduling, no fancy signal processing, no interference mitigation).

Re:Actually, no. (1)

Ungrounded Lightning (62228) | about 8 months ago | (#46289853)

The only similarity between DIDO and MIMO, as far as I understand it, is that they both use multiple antennas to send and receive separate data streams simultaneously. But their signal processing schemes are very different.

Not really. See below.

In broad strokes: DIDO does the signal processing (matrix math) on the transmitter side while MIMO does it on the receiver side.

Nope. MIMO does it at BOTH ends, to multiply the bandwidth between the two ends of the path by up to the number of antennas at the end with the smaller antenna count. The subchannels are, or can be, actually received by all the receive end antennas and sorted out in the receiver.

DIDO is MIMO with:
  - The computation done so each remote-end antenna gets exactly one subchannel of the data (rather than a weighted and phase-shifted sum of all subchannels).
  - The antennas at both ends very widely separated.

Sorting the signals this way allows the "remote end" to consit of many, independent, single-antenna devices, each with an independent data pipe as broad as the assigned spectrum. The wide separation of the antennas at both ends of the link makes a very large coverage area practical. Motion of the remote end devices just corresponds to a variation in the position and spacing of a remote-end MIMO device's antenna, requiring update of the parameters of the computation.

Explanation from TFA (5, Informative)

tech.kyle (2800087) | about 8 months ago | (#46288291)

Should have been included in summary, imo.

That’s where things get interesting. Say, for example, you play a YouTube video. The pCell data center would request the video from Google’s servers, and then stream it to your phone through those 10 antennas. But here’s the key innovation: No one antenna would send the complete stream or even part of the stream. Instead, the data center would use the positions of the antennas and the channel characteristics of the system, such as multipath and fading, to calculate 10 unique waveforms, each transmitted by a different antenna. Although illegible when they leave the antennas, these waveforms would add up to the desired signal at your phone, exploiting interference rather than trying to avoid it.

Re:Explanation from TFA (1)

Anonymous Coward | about 8 months ago | (#46288885)

Sure it can be done - for one user. How that set of 10 antennas could do it for 1,000 users simultaneously is beyond me.

Re:Explanation from TFA (0)

Anonymous Coward | about 8 months ago | (#46290043)

The waveforms are computed by a centralized supercomputer in real-time. It's obviously computationally intensive to figure all of this out for 1,000 or 10,000 or 100,000 points, but contemporary computational capacity is now sufficient to meet the challenge.

Re:Explanation from TFA (1)

camperdave (969942) | about 8 months ago | (#46289395)

But here’s the key innovation: No one antenna would send the complete stream or even part of the stream.

So... the antenna sends nothing. Brilliant, now to hook it up to some torrent sites.

CDMA (0)

Anonymous Coward | about 8 months ago | (#46288329)

This seems an awful lot like CDMA http://en.wikipedia.org/wiki/Code_division_multiple_access to me

The new moble tracking system. (1)

slackware 3.6 (2524328) | about 8 months ago | (#46288331)

For when the GPS is turned off. Or maybe pCELL combined with GPS means that google maps won't send me the wrong direction down a deadend road again.

Re:The new moble tracking system. (1)

jratcliffe (208809) | about 8 months ago | (#46288561)

The wrong direction down a deadend road? So, once you left the area, you could never return?

Re:The new moble tracking system. (1)

David_Hart (1184661) | about 8 months ago | (#46289857)

The wrong direction down a deadend road? So, once you left the area, you could never return?

I have a Jeep... There is no such thing as a wrong direction down a dead-end road... (grin)

Re:The new moble tracking system. (1)

Immerman (2627577) | about 8 months ago | (#46288965)

Well, it'll be a lot more accurate, but it's already trivial to track the position of *any* cellphone in the city within at least block or so without using GPS. Being able to narrow that down to tracking its motion around the room is a lot creepier, but probably not a lot more abusable.

Probably trivial (-1)

Anonymous Coward | about 8 months ago | (#46288393)

Distributed In Distributed Out sounds like two phased array stations to me http://en.wikipedia.org/wiki/Phased_array . So I would guess that they establish directional links between the station and the receiver, which can autoconfigure so you don't need to sweep with a dish or a Yagi antenna. Maybe they have a few more tricks in their self proclaimed "complicated mathematics" to modify side lobes, but I doubt that they can do much more unless the distributed antenna arrays are very large. The linked description is written in such a shrill marketing style that all my bullshit senses are tingling, but who knows maybe they will let the engineers talk at some point in the future.

The only known unknown (1)

ThatsNotPudding (1045640) | about 8 months ago | (#46288401)

All that's left is figuring out *who* will be suing him first. CISRO? Intellectual Vultures?

TowerS (0)

Anonymous Coward | about 8 months ago | (#46288497)

Finding a single tower that is allowing your carrier access can be a pain in some areas, pCell sounds like it requires many towers to be effective AND it needs to know your exact location AND it needs to know the exact locations of the towers AND it needs a massive amount of computational power. It maybe for urban areas it might someday become a reality but for rural areas it would probably be pointless.

Re:TowerS (0)

Anonymous Coward | about 8 months ago | (#46288843)

maybe for urban areas

...so most of the world's people, then? Yah, that could be useful.

NSA is Behind This (1)

trydk (930014) | about 8 months ago | (#46288669)

I know the NSA is behind this ... I mean, tracking phones down to centimeter precision.

Re:NSA is Behind This (0)

Anonymous Coward | about 8 months ago | (#46288893)

Listen, the NSA already knows exactly where you are, who you talk to, and how many hands you use when you type. If they didn't, I could see how this would increase their powers.

Re:NSA is Behind This (1)

strstr (539330) | about 8 months ago | (#46288999)

wiseman.. http://www.oregonstatehospital... [oregonstatehospital.net]

You will enjoy learning about NSA directed energy capability, satellites, and radar abuses..

Re:NSA is Behind This (0)

Anonymous Coward | about 8 months ago | (#46289705)

You're a fucking MORON, Todd. You're delusional.

How's your court case going? Still masturbating in public parks and claiming the NSA made you do it?

Enjoy your freedom, very soon you will be invited to stay perminantly in a private suite at the Salem Funny Farm.

directed-energy antenna system.. (1)

strstr (539330) | about 8 months ago | (#46288673)

we need to focus our technology on designing base stations and cellphones that utilize directed-energy, focusing their signals at each other, versus using omnidirectional energy (this creates a lot of waste, and the energy penetrates and bombards people/things it doesn't necessarily have to,..).

with an imaging system like this, the base station can see each device independently, like a satellite does from over head, and an array of light-guns or phased array antennas can direct energy at each device for dedicated bandwidth and perfect signal reception over greater distances. an added benefit is lower output power works, and many devices can share the same spectrum..

the device itself would pick up the directed signal, and similarly lock on to the base station and beam a laser/directed energy right at it with dedicated bandwidth.

The military has technology like this already in deployment which they generally use to attack people.. http://www.oregonstatehospital... [oregonstatehospital.net]

Re:directed-energy antenna system.. (0)

Anonymous Coward | about 8 months ago | (#46289863)

Seriously, Todd, off your THORAZINE today? You really ought to seriously consider checking in to your home-away-from-home at the Funny Farm in Salem.

Tell me, Todd, still ferociously masturbating in public parks? Hows that court case of your going?

3G Soft Handover on steroids? (1)

tree_frog (113005) | about 8 months ago | (#46288761)

This sounds very like the existing 3G soft handover feature.

I'm not involved in that area of telecoms these days, but I do recall that the network equipment manufacturers were finding it very difficult to get working, and requiring some serious compute power.

Wrong problem (2)

DriveDog (822962) | about 8 months ago | (#46288871)

As cool as the technique sounds, for me it's a solution to the wrong problem. Maybe some of you have trouble getting your videos streamed in congested cities, but I don't use my phone for that. My complaints are all about poor coverage in rural and even some suburban areas. And I have Verizon, which because it unfortunately swallowed Alltel (I'm not aware of any Alltel customers that were happy about that), has much better coverage in my area than the rest. What they need is a few hundred thousand more nodes in rural and suburban areas on ordinary utility poles, inside of steeples, etc.

Re:Wrong problem (2)

NoImNotNineVolt (832851) | about 8 months ago | (#46289275)

Due to the nature of population distribution, the issue you described is relevant only to a small minority of users. Over 80% of Americans live in urban areas (as of 2010 [reuters.com] ), despite urban land accounting for only 2.65% of the total US land area. In other words, your issue is your issue, and most people don't share your priorities.

While you have my sympathy, you can't expect wireless carriers to ignore the majority of their customer base and start chasing after the long tail.

Re:Wrong problem (0)

Anonymous Coward | about 8 months ago | (#46289281)

As cool as the technique sounds, for me it's a solution to the wrong problem. Maybe some of you have trouble getting your videos streamed in congested cities, but I don't use my phone for that. My complaints are all about poor coverage in rural and even some suburban areas. And I have Verizon, which because it unfortunately swallowed Alltel (I'm not aware of any Alltel customers that were happy about that), has much better coverage in my area than the rest. What they need is a few hundred thousand more nodes in rural and suburban areas on ordinary utility poles, inside of steeples, etc.

Well if YOU don't use your cell phone for that, well no one else would...

Re:Wrong problem (0)

Anonymous Coward | about 8 months ago | (#46291009)

I'm pretty sure no one else will use DriveDog's cell phone for that.

Re:Wrong problem (1)

Kjella (173770) | about 8 months ago | (#46289371)

Well, it might not be you but I've seen the traffic numbers and there's an absolutely massive increase in mobile traffic. When people were on laptops, they mostly used wireless nets. Now with smartphones, phablets and tablets with built in 3G/4G connections they tend to get used a lot. And many of them are high PPI devices, meaning you're still sending HD signals even if it's on a 4-10" screen.

Interesting tech (0)

Anonymous Coward | about 8 months ago | (#46288881)

The tech sounds interesting, but if you want more bandwidth in a high density area, use wifi, no new tech needed.

ROTFLMAO (0)

Anonymous Coward | about 8 months ago | (#46288903)

What a load of crap.

Yay (0)

Anonymous Coward | about 8 months ago | (#46289173)

Since I get about ~250kbps on Verizon's 4G LTE network in downtown Los Angeles with -60dbm signal, does that mean I might reach DSL speed one day?

burb (0)

Anonymous Coward | about 8 months ago | (#46290319)

If this would solve the actual problem of transmission capacity in cellular networks why we do have data buckets? The problem is not the channels per cell or the transmission rate per channel. The problem is located in transmission capacity from BTS/eNodeB in uplink. The issue is not fixed by providing more radio capacity. Sorry, no revolution with this.

Spectrum (i.e. RF congestion), not network. (1)

buttfuckinpimpnugget (662332) | about 8 months ago | (#46290411)

Still a great thing if it works, but NodeB UE does not a network make. Don't forget backhaul and the core.

The size of the bubbles isn't adjustable. (0)

Anonymous Coward | about 8 months ago | (#46290619)

The size of the bubbles depends on the wavelength of the signal, and will be about 10cm for typical mobile frequencies.

Hence, if you move your phone more than 10cm before the tower can recompute your location, you loose all signal... Unlucky!

That will be a serious problem while driving down freeways or in trains.

I'm feeling Déjà vu (2)

ras (84108) | about 8 months ago | (#46291227)

This reminded me of the claims Steve Perlman [venturebeat.com] made in 2011. He said his technique would overcome Shannon’s Law. He was justifiably ridiculed. At least this mob isn't claiming they can break the laws of physics.

Oh wait, this is Perlman [venturebeat.com] , peddling the same dog and pony show. Only this time he's got an article in IEEE Spectrum to print his claims. I hope that means he no longer says he can beat the laws of physics into submission.

The original claims of the impossible aside, the idea was to monitor the signal of each phone in real time from a central point, do some calculations to figure out the path distance from each antenna the phone, then do some more calculations to split up and phase change outgoing signal so the signals from those antennas so they constructively interfered to produce the wanted signal at the phone. The tracking has to be damned accurate - much better than GPS because a 1Ghz mobile phone signal has a wave length of about a meter, and you need better than 1/4 of the wavelength. And it has to be fast, because if the phone or objects around it move it all goes to put. So if you are walking at comfortable 1 metre per second, in 0.25 seconds it's all gone to pot. In a car that drops to 0.02 seconds. Oh, and since we as talking 1GHz, we have to measure it within a few 100 picoseconds. And since you don't use one antenna to service just one phone, he will have to be doing this for 100's of phone simultaneously. Oh, and that means when he is calculating the phase and amplitude of the signal his antenna is generating, he has to solve 100's linear equations with 100's of variables so he can ensure each signal he sends from each antenna adds up to what each phone needs. And since the collective antenna group is sending at oh, say 100Gb/s and he has to do this for every fucking bit, so he has 10 picoseconds per bit to do it in.

Yeah, right. It will be out by Xmas, I'm sure.

Re: I'm feeling Deja vu (0)

Anonymous Coward | about 8 months ago | (#46292077)

Watch the videos. In one, he shows the antennae of several LTE devices with pCell technology turned on then off, and moves the devices and they predictably fail, then with the full set of features enabled, the darn things stay at full stream. Ditto putting the antennae within a centimeter of each other. Repeated with eight LTE iPhones. All in a 5GB connection. Does the same thing with a half dozen 4K Netflix streams on a 10 GB pipe.

Is it needed? (0)

Anonymous Coward | about 8 months ago | (#46291469)

Seriously, what is up with this maniacal "need" for speed on cell PHONES these days? Are you all to stupid to realize that the providers only wants you to download data faster so they can charge you more!?

Load More Comments
Slashdot Login

Need an Account?

Forgot your password?