john CioffiOn May 10, 2017, at the Paris Summit, John Cioffi will describe a path to a terabit over copper. That is not a typographic error, although John's ideas are far beyond the state of the art. using 106 MHz is now reaching a gigabit. 212 MHz is soon to ship, with correspondingly high data rates. Alcatel has pushed into higher spectrum to demonstrate 10 gigabits. Physicists and astronomers work with submillimeter waves from 300 GHz to 3 terahertz. Nothing like that is used in communications

Wireless systems use much higher frequencies. 28 GHz & 39 GHz 5G millimeter systems are just getting to the field, with millions likely to ship next decade. 70 GHz backhaul systems are in commercial production. Even faster wireless systems are in the labs. Submillimeter waves begin at 300 GHz and go up to 3 terahertz. While speeds like that have not been used in communications, they are common in physics and astronomy. 

Wikipedia notes, ""As of 2012, viable sources of terahertz radiation are the gyrotron, the backward wave oscillator ("BWO"), the organic gas far infrared laser ("FIR laser"), Schottky diode multipliers, varactor (varicap) multipliers, quantum cascade laser,] the free electron laser (FEL), synchrotron light sources, photomixing sources, single-cycle or pulsed sources used in terahertz time domain spectroscopy such as photoconductive, surface field, photo-Dember and optical rectification emitters., and electronic oscillators based on resonant tunneling diodes have been shown to operate up to 700 GHz."

Many problems need to be solved before 300 GHz and higher can be used in, especially over copper. If this came from anyone but John Cioffi, I'd consider this about as likely as experimental verification of string theory in my lifetime. John - a friend - has four times since 1993  demonstrated DSL possibilities no one in the industry thought possible. He used DMT to build a system that delivered 6 megabits when others thought 1.5 megabits was the practical limit. At the Paris conference, you'll see production-ready equipment delivering a gigabit. Gigabit DSL would be impossible without John's invention, Vectored DSL. Vectored DSL, invented in 2002, took more than a decade to come to market. By 2016, Adtran alone has shipped ten million vectored ports. Subm may well take longer. 

I do not believe he will be bringing a working system to the Paris show. 

The Terabit DSL
Investigating the potentials of the use of massive tiny transmitters in a coordinated array where the number of such transmitters significantly exceeds the number of wires in the shielded binder. This approach essentially treats the binder of wires as a highly complex waveguide in which effectively higher-order transverse/transmission modes could exist and be exploited at submillimeter wavelengths to open bandwidth possibilities well beyond conventional DSL transmission. We explore this possibility and channel models for it.

John Cioffi, 
Professor Emeritus of Electrical Engineering,
Stanford University



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May 8

FNN/5GW/DSL Prime in an experimental short form, with News beneath

The news: Verizon $20B 5G network to 1/3 to 1/2 of the U.S. is on; John Cioffi Wednesday will explore terabit DSL; Telefonica CTO rips the 5G hype and rush; NTT CTO reverses position, now expects mmWave 2020; Super Wi-Fi is delivering 300 meg symmetrical at a fraction of mmWave costs; AT&T has massive unused spectrum holdings; Belgacom: Nothing “needs” 5G;  Ralph de la Vega and a story worth reading: 5 stories

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New York: Verizon is going ahead full speed with a $20B 5G network to 1/3 to 1/2 of the U.S. Not a trial, test, fake, or limited. Lowell McAdam has made the decision although it’s not announced. 6 part article linked below.

Paris: Terabit DSL (not a typo) is John Cioffi’s talk 9 a.m. Wednesday at the Paris Summit. If it were anyone but John, I’d think this pure science fiction. If testing proves out, this will be historic. (Submillimeter wave with waveguide.) Four distinguished Professors think John’s on target

Spain: CTO Enrique Blanco of Telefonica warns the rush to get something called “5G” is forcing some very bad decisions. He asks, “So what's new? They simply end up extending 4G capabilities [with] little differentiation from advanced LTE technology.” Enrique is saying publicly what his peers tell me privately. Some wisdom

Japan: Seizo Onoe, NTT DOCOMO CTO, changed his mind and now expects mmWave in 2020. In 2015, he predicted little mmWave mobile before 2022-2023. That became the common wisdom among leading engineers. The technical progress in the last year has been extraordinary and the costs are way down.

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