Jobs wanted own network with unlicensed spectrum

[Mosby]

Steve Jobs initially hoped to create his own network with the unlicensed spectrum that Wi-Fi uses rather than work with the mobile operators, said wireless industry legend John Stanton.

Stanton, currently chairman at venture capital firm Trilogy Partnership, said he spent a fair amount of time with Jobs between 2005 and 2007. "He wanted to replace carriers," Stanton said of Jobs, the Apple founder and CEO who passed away recently after a battle with cancer. "He and I spent a lot of time talking about whether synthetically you could create a carrier using Wi-Fi spectrum. That was part of his vision."

snip

http://www.macworld.com/article/163633/2011/11/venture_capitalist_jobs_wanted_own_network_with_unlicensed_spectrum.html

I think what Jobs was talking about is ultra wideband technology:

http://bwrc.eecs.berkeley.edu/Research/UWB/
http://en.wikipedia.org/wiki/Ultra-wideband

Cell phone carriers already use a type of shared bandwith transmission called CDMA, with an ultra wide band capability we would not need the cell companies at all, the phones themselves would set up the network without the need for cell towers.

What needs to happen to facilitate this? Open Spectrum:
http://www.greaterdemocracy.org/OpenSpectrumFAQ.html

[gateley]

1. How interesting! Thanks!! nt

[TheWraith]

2. 2.4 GHz is not ultra-wide-band.

It appears what Jobs was talking about or thinking was something akin to city-wide WiFi networks, but apparently using some new kind of technology designed for longer ranges than WiFi is right now.

Also, a peer to peer UWB network sounds good, right up until you realize that your phone would stop working if you were more than say 50 feet from another cell phone.

[Mosby]

3. UWB would use all of the cell phone bandwidth

There are problems of course:

Ultra-wideband (UWB) <1>, <2>, <3>, <4> represents a new
paradigm in wireless communication. The unprecedented radio
bandwidth provides advantages such as immunity from flat
fading. Two primary challenges exist: (1) how to collect
energy over the rich multipath components; (2) extremely
high sampling rate analog to digital conversion (A/D). Time
reversal <5> provides a promising solution to the first problem
<6>. In particular, the concept of time reversal has recently
demonstrated in a real-time hardware test-bed <7>, <8>. At the
heart of time reversal, the channel itself is exploited as a part
of the transceiver. This idea makes sense since when few
movements exist, the channel is time-invariant and reciprocal
<9>. In principle, most of the processing at the receiver can
be moved to the transmitter—where energy consumption and
computation are sufficient for many advanced algorithms.

http://dsp.rice.edu/sites/dsp.rice.edu/files/cs/CS_Based_UWB.pdf

[TheWraith]

5. No. We're talking about two different things.

First off, basic radio spectrum: as the frequency increases, so does the amount of information you can transmit, but the range of that transmission and it's ability to go through obstructions (like buildings) goes down.

Cell phone signals in the US are at blocks near 700, 850, 1700, 1900, and 2100 MHz. The WiFi band, which you don't need a license to operate on, is around 2400 MHz. Ultra-wide-band is between 3100 MHz and 10,000 MHz.

Ultra-wide-band is considered revolutionary in some ways because it allows you to move a great deal of information wirelessly over short distances, amounts comparable to using high quality wired communication. One example would be being able to send a video signal from your smartphone to your TV wirelessly in HD quality, rather than needing a cable to do that.

However, UWB is designed around the assumption of being able to use vast swaths of spectrum, i.e. 500 MHz or so, to do this. 500 MHz is more spectrum than is allocated for all US cell phone carriers put together. You can get away with that on UWB because at the frequencies it uses, there's little else to compete with it and the transmissions don't go far enough to be an interference risk. If you tried to boost that transmission power to increase range, or moved to a lower frequency, you'd start to see major problems with interference and/or capacity.

In fact, the current movement in terms of wireless communication is to go for lower frequencies, in the 150 to 700 MHz range, because these get better range than existing phone blocks.

[Xithras]

4. He may have been thinking about organic networks too.

I know that it's been experimented with by many companies, including Apple. In a nutshell: Your phone doesn't connect to a "tower", but instead simply seeks out another phone within wi-fi range and connects to it. From their phone, the signal branches out to another phone within range of them. The signal keeps hopping and hopping until it gets within range of an Internet connected wi-fi base station that can route the signal over the Internet. It's wi-fi calling without infrastructure.

Tests have indicated that phone networks like this would work very well in urban areas, and would even outperform current cell phone technologies in low-signal environments, but the concept completely falls apart once you move out into the suburbs and rural areas where you may spend a significant amount of time beyond the wi-fi range of other cell users. The process assumes an unbroken chain of users between you and the closest hotspot. If that chain doesn't exist, you get no signal.

It's still a viable concept, but wi-fi range needs to improve before it can really become practical. The current range of an 802.11n connection maxes out a bit over 800 feet, which simply isn't enough. 802.11y might be a potential candidate with its 3 mile range, but there are all sorts of technological and regulatory problems that would need to be worked out first.

[Fumesucker]

6. Yes, that sounds more likely to me..

It's also robust, harder to knock out than centralized systems.

Wifi repeaters could be spread around rather like small cell towers in more remote areas.

[TheWraith]

7. It sounds to me more like they were thinking about something akin to a Metropolitan Area Network.

These were all the rage a few years ago, cities installing WiFi over large areas. I don't know what's happened to it since, I haven't stayed up to date on that sort of thing. But the idea was that you could basically skirt the laws regarding the maximum allowed power of WiFi gear to create strong WiFi networks over large areas, often tens of square miles. If you started with a new standard working from the ground up, you could probably create even better networks--2.4 GHz WiFi was never designed to be used like that, but rather as an ethernet substitute.

Granted it would only be practical in fairly urban areas, but it's certainly possible.

[Canuckistanian]

8. The 700MHz band might be the solution to that

Where I work (a Government Research facility), we're working on a new protocol that's sort of like WiFi. But we're using the 700MHz band.

As we speak, we've got a video link up and running at a distance of about 22kM (13.7 miles), with a bandwidth of over 1.5Mbps.

It's not the work of my department, but the terminal is up and running right across from my lab.

[TheWraith]

9. That's why a lot of tech companies are pushing unlicensed or "white space" in the 150-700 band.

Mostly for broadband rather than phones, but it could work for either. Microsoft, Google, Dell, HP, Intel, Philips, Earthlink, Samsung are the major pushers. The over-the-air broadcasters are against it though, on the claim that they're worried it could interfere with their transmissions, and they're suing.