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



Often interesting


Mobile World Congress, Barcelona, Feb 27-March 2 100,000 mob Barcelona. Fares from New York are triple the usual price and hotels even higher - if you can find one less than a hour from the city. Everybody who is anybody goes so everybody who is anybody goes. Beyond the pomp and hot air are a slew of top technical people. Seek them out and make sure yo make appointments in advance with the people you want to see. Hint: You can still get rooms at the hostels in town. Next year, book way in advance to get one of the hotel rooms GSMA have negotiated with the city.

Digital Hollywood Media Summit, New York March 7-8. Victor Harwood always had an enormous number of top people in an almost overcrowded schedule. Senior folks from advertising, all media, marketing and more. VR and AR are heavily represented, from the talent to the salesmen. The price is about half what most shows charge and there are discounts for those with limited resources, including students.  A great way to learn what the most advanced in these fields are doing.

Brooklyn 5G Summit April 19-21st The most sophisticated people in wireless will be there, from the CTOs of NTT and Nokia to the most respected academics on the planet. Incredible S/N. If you can't come to Brooklyn, you must watch the stream. It takes two or three years for most people to catch up to what's learned here. Summit, Paris May 9-11 Trevor Linney of BT is deploying 10M lines. John Cioffi promises something astonishing. Everyone in the industry will be there except Broadcom, being their usual antisocial self. On the 9th, Hubert Mariotte of the standards committee has a deep technical tutorial and I have a session for everyone else.

TNO Ultrabroadband Den Haag June 12-15 Always a strong group.

I'm moving from to everything since July 2014 is here.


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