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New 'pCell' Technology Could Bring Next Generation Speeds To 4G Networks
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.
So like Warp 9.5 then?
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.
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.
"-1 Troll" is the apparently the same as "-1 I disagree with you."
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.
If we colonize Mars, it won't be the World Wide Web anymore. UWW?
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.