Perlman's pCell Loaded With Hype But NY Times Calls 48 Megabits Over 100 Megahertz Of Spectrum Breakthru
Steve Perlman's pCell claims require a reality distortion field. Update: 2 professors confirm below. Second Update. Met with Perlman and engineers. He has real engineers who did a slick trick using iPhones as LTE receivers. They may also have some neat tricks in MU MIMO and SON. Not close to their claims and most not new. Update 3: They don't give details about the software inside their server. It could be seriously interesting as improvements on how cells work together. Or it could be not. More to come. Original: Nick Wingfield in the Times believed a demo that could be reproduced on a cheap home WiFi router demonstrates a wireless breakthrough. The Times showed 8 iPhones simultaneously playing HD video. Reporter Nick Wingfield wrote, "that would ordinarily bring a cellular network to its knees." Netflix streams at 5.5 mbps or less, so 8 streams is less than the 50 megabits even a modest cell site delivers, with 100-150 megabits becoming the standard rapidly. Within the space of a loft, speeds would be much higher. A 300 megabit router at Fry's this week costs $44.95 ; Fry's is selling a gigabit router for $129.95 . Ericsson has demo'd 800 megabit LTE in a van driving around Stockholm. 48 megabits or even 400 megabits in a small space is not an advance.
What Steve really has is a lot of hot air and what appears to be a prototype MU-MIMO system. If he has that production ready, that would be an important advance similar to work going on at all the major wireless vendors. That's similar to what Stanford researchers and many others have been working on for years. Literally in the last century, Stanford Professor AJ Paulraj described such systems. He predicted MIMO would one day produce a 1,000x and higher improvement in wireless speeds and that the theoretical limits could be 1,000,000x. Paulraj in 1993 invented MIMO, likely the heart of pCell.
Paul won this year's Marconi Prize for that invention . When Perlman made similar claims in 2011, I asked Paul and he replied
Multiuser transmission from a hub with single antenna allows one to transmit at full rate to one user and up to some fraction of full rate to second user etc. Complex encoding and decoding. If we have mulltiple antennas at the hub, we can send full rate to each of multiple users as long users are chosen to be quasi orthogonal spatially. This mode is now in use by millions of wimax users (and soon LTE). Also called multi-user MIMO. Easy encoding and decoding. Too many red flags in the desc. including irrelevant connections. Claiming complex math to disguise the scheme is also a red flag too.DIDO write up is vague and filled with irrelevant stuff - one has to be very skeptical.
Professor (Emeritus) Dept. of Elect. Engg.
Update: Just got these comments
Andrea Goldsmith, Stanford
I remember when DIDO first hit the presses. The white paper on it (http://www.rearden.com/DIDO/DIDO_White_Paper_110727.pdf) was so vague as to be laughable, and the only technology I could discern through the smoke and mirrors was MU MIMO. I thought we had buried DIDO back then, but apparently not. Thanks for your quick response to this ridiculous "discovery"
11:07 AM (4 minutes ago)
Ted Rappaport, NYU
Dave: I have heard and seen this stuff from this group over the past few years, but have yet to see theory or detailed analysis or explanation that would allow this to be independently verified or generally understood by technically sophisticated people.
Without more technical details, this likely strikes many technically literate people as hype,fluff, and PR.
(Both have done important work in related areas.)
It's too early in the morning for me to call Paulraj in California but I'll confirm with him later in the day his remarks still apply. Meanwhile, I pointed the Times writer to some top engineers in this field, Paulraj and Andrea Goldsmith at Stanford, Ted Rappaport at NYU and Jerry Foschini at Bell Labs to get expert opinion.
Artemis is doing a demo at Columbia in a few hours I'll attend. Their pr, below, is full of errors. They did not "invent an entirely new approach to wireless." This stuff is already in the wireless textbooks. If they did develop "a practical system that can be rapidly deployed," that would be important. I doubt it. The press release quotes marketing expert John Sculley: “pCell is an authentic ‘moon shot’ disruptive invention," but no independent engineers. There's no evidence this system works as promised over a wide area in the real world.
A Ramamujan comes along once a century and revolutionizes mathematics; hypesters appear weekly in my email.