March 27, 2007 4:00 AM PDT

Intel modifies Wi-Fi to add mileage

BERKELEY, Calif.--Intel has come up with a form of Wi-Fi that would let a laptop in San Francisco connect to the Internet from a base station in San Jose, Calif.

And there would still be about 10 miles of wiggle room to spare.

Academics and researchers from the company's labs have created a system that lets Wi-Fi signals, which ordinarily carry a few hundred feet, instead travel 100 kilometers, or more than 60 miles, said Eric Brewer, director of Intel Research Berkeley, a lab owned by the company that cooperates on research projects with the University of California at Berkeley.

"It is regular Wi-Fi hardware but with modified software," he said.

To show it works, Intel has set up a link between its labs in the downtown section of this Bay Area city and the university's Space Science Lab, about 1,200 feet up and about 1.5 miles away on Grizzly Peak Boulevard. The receiver in the office consists of a directional antenna linked to a modified--but otherwise standard--wireless access point.

The system isn't designed for the U.S. or Europe. Instead, it is part of the chip giant's efforts to bring computing technologies to people in emerging markets. The communications infrastructure in most of these countries is fairly anemic and most of it is concentrated in cities. Villages, where a large portion of the population lives, are effectively cut off from the outside world except by car, bus or footpath.

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These Wi-Fi antennas, say Brewer and others, could serve as important links in a chain. Villagers would connect to a Wi-Fi antenna in their town or region, which would then relay the signals through several other towers until it came to a fiber link that connected the villager to the Internet.

In a sense, these long-range Wi-Fi antennas would perform the same function as WiMax, a long-range wireless technology that many, including Intel, are experimenting with now. The difference is that a WiMax tower costs about $15,000 to $20,000. The long range Wi-Fi towers might only cost $700 to $800.

Additionally, long range Wi-Fi could spread faster, Brewer said. The radio spectrum employed by WiMax is regulated by local telecommunications authorities. Putting up towers or offering services can require getting governmental permission.

Wi-Fi operates in the unlicensed portion of the spectrum. Thus, villages could join a network incrementally. Some networks could also leverage both WiMax and Wi-Fi: Pakistan, among other emerging nations, is investing heavily in WiMax.

Intel is considering conducting a trial of this technology, or components of it, in Uganda later this year.

How it works
One of the big differences between standard Wi-Fi and Intel's long-range version lies in the fact that the long-range signals are directional: they are tuned to travel from one antenna to another one and nowhere else. A standard Wi-Fi antenna broadcasts its signal in a 360-degree circle.

Creating a direct signal isn't easy. The antennas need to be precisely aligned with one another, and physical objects that get between the two can interfere with the signal.

"It is hard to align them," said Alan Mainwaring, a scientist at Intel Research Berkeley. "The first thing that happens is that kids play on the tower."

To that end, the company has developed a "steerable" antenna. The physical antennas themselves aren't steered--instead, the signal between the towers is guided by an electrical signal. Electrical steering also has the advantage in that the physical antennas can also move out of alignment, or even be put into the ground slightly off-kilter, without destroying signal integrity.

The lab has made one system out of "L" brackets and wood, among other components, and will come out with a second generation of antennas in the relatively near future. (Some of the technology for the steerable antenna comes from professor Alexey Umnov of Nizhny Novgorod State University in Russia. Intel has research facilities in that city, too.)

Additionally, a lot of the protocols and procedures in ordinary Wi-Fi communication are eliminated. Handshaking, which allows a PC and a wireless router to link up in an ordinary Wi-Fi network, and collision detection are eliminated.

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Old news
This is old news - people have been using directional antennae to
improve WiFi range for some time. Here is a link back to 2000 with
a hack to mod the original Apple AirPort systems ( <a class="jive-link-external" href="http://" target="_newWindow">http://</a> ). He
managed 14km, but Lucent engineers were allegedly getting 57km
(and that would have been with 802.11b!).
Posted by pauldickinson62 (23 comments )
Reply Link Flag
old news 2
working link
<a class="jive-link-external" href="" target="_newWindow"></a>
Posted by pauldickinson62 (23 comments )
Link Flag
These guys made it 125 miles
<a class="jive-link-external" href="" target="_newWindow"></a>

At the DEFCON 2005 wifi shootout - team "iFiber Redwire" made a standard, unamplified 802.11b connection reach 125 miles using directional antennas.
Posted by Arbalest05 (83 comments )
Reply Link Flag
that wifi test
Did they ever do anything practical with it, or just experiment for a few days and leave it at that?
Posted by michael kanellos (65 comments )
Link Flag
WiMax works in multiple spectrum frequencies from 800Mhz to 6.3Ghz, that includes the public spectrum of 2.4Ghz and 5.3/5.8.
Posted by liquidblues (8 comments )
Reply Link Flag
Now install it in the D/FW area, Africa can still use smoke signals. We can't we are under a burn ban.
Posted by lormahoykyd2007 (8 comments )
Reply Link Flag
Congratulations, Intel invented the repeater
Signals relayed by radio towers? What a novel idea!
Posted by richardhaskins (5 comments )
Reply Link Flag
Whats next?
Maybe next they'll try bouncing off a sattelite :-)

Seriously, though, I dont think the innovation is the 'repeater', but getting the signal to the repeater. Getting a standard wi-fi signal 100 km is quite an accomplishment
Posted by LuvThatCO2 (187 comments )
Link Flag
Software steering sounds good
The big point of this article is the innovation of being able to "steer" the signal via software without physically moving or re-aiming the antennae. That's pretty cool considering how much effort can be expended trying to align a transmitter and receiver.This might mean that one wouldn't need as robust of an antennae tower. It all remains to be seen what may actually materialize for real use, but I have to give them credit for working to improve things.
Posted by mhurwicz (4 comments )
Reply Link Flag
This suggests a cure for the signal deflection that plagues communications in rainy parts of the world.
Posted by Phillep_H (497 comments )
Link Flag
The first thing that happens...
... is kids play on the tower? What? These guys hear of a fence?
Posted by shoffmueller (236 comments )
Reply Link Flag
or grease?
Grease the polls with some really foul smelling stuff.

It only takes about ten feet at the bottom and you'll never have to worry about it again.
Posted by binaryspiral75 (27 comments )
Reply Link Flag
802.11N does the Beam Forming Electronically
There is little here that is new. I personally set up long relays using frequency-hopping 802.11 radios back in the mid 90's. Nothing more than adding a dish behind a radio.

The good news is that its already done automatically with 802.11 Draft-N
Posted by disco-legend-zeke (448 comments )
Reply Link Flag
13 years late to the party
We've been adding directional antennas to wireless cards and going long distances since 1994 - since before the Wi-Fi protocols were even created. Further, thousands of people have been adding directional antennas to Wi-Fi cards for many years. Who in the Intel PR world was not aware of this?
Posted by guru22 (1 comment )
Reply Link Flag
My favorite line
"The receiver in the office consists of a directional antenna linked to a modified--but otherwise standard--wireless access point."

Ah I see; so except for the modifications that make it non-standard, it's standard.
Posted by jmuvanwilder (1 comment )
Reply Link Flag
They voted FOR modified equipment before they voted AGAINST it...
Posted by wifiwaves (4 comments )
Link Flag
he said ...non-standard ---- (( yett )) standard

good one ....
Posted by audioguy22 (1 comment )
Link Flag
Pakistan is investing a lot in WiMax, but...'s a a private telecom that's doing it (Wateen Telecom, a UAE concern). However, there really isn't any resistance to it because there's always someone in the government that's eager to make a buck while signing-off on such endeavours. The higher the overall outlay, the bigger the kickback

If Intel can ever manage to make this tech commercially available, it'd be great for the third world, because of the low cost involved in the relay towers and also, it seems, that today's wifi cards would work just fine with a driver upgrade.

For a broke country, economical, modified tech is a lot better than expensive, new tech that does pretty much the same thing.

<a class="jive-link-external" href="" target="_newWindow"></a>
Posted by bingobob (2 comments )
Reply Link Flag
Brussels Wants to Tax Antennas for Wireless Internet.
Hopefully this won't come to North American any time soon:

FROM: <a class="jive-link-external" href="" target="_newWindow"></a>
Brussels Wants to Tax Antennas for Wireless Internet
By Luc Van Braekel
Created 2007-03-22 23:07

Olivier Maingain, the mayor of Sint-Lambrechts-Woluwe, one of the 19 Brussels boroughs, is planning to tax all "antennas for the transmission of data". Each antenna will be taxed a staggering 4,000 euros per year. Such antennas are used for WiFi or WLAN, i.e. wireless internet or wireless networks over relatively short distances. While the small antenna on your wireless router could theoretically be taxed, the new tax seems to target WiFi-antennas that can be seen from the outside, i.e. that are positioned on the outside of buildings. If the owner of the aerial cannot be identified the owners of the buildings have to pay the new tax.

Some Brussels boroughs are already taxing companies on the number of computer screens in their offices. The government of the Brussels Region, however, considers this tax so detrimental for business investments and for the image of the region, that it offers money to boroughs that do not levy the computer screen tax.

Sint-Lambrechts-Woluwe has 50,000 inhabitants. It is a wealthy residential neighbourhood, close to the NATO and EU headquarters, where many Eurocrats and American expats live.

Apart from being mayor of Sint-Lambrechts-Woluwe (or Woluwe-Saint-Lambert as he calls it in French), Maingain is a member of the Belgian House of Representatives and the leader of the Front des Francophones (FDF). The FDF is a party defending the linguistic rights of the French-speaking inhabitants of Brussels. It is a partner of of the governing liberal party Mouvement Réformateur (MR). Vehemently opposed to the historic Dutch (Flemish) roots of Brussels, it aims for the recognition of French as an official language in the Flemish countryside surrounding Brussels. The FDF is known for its insidious hate speech towards Flemings.
Posted by Dave_Brown (46 comments )
Reply Link Flag
WoW - The Emporer just got new clothes
We have Europe's largest non-commercial wireless network running here with more than 5.000 homes online and more than 300 "radio towers" (mostly just tall buildings, trees and anything else that raises a few feet above ground - surprise: It runs 802.11b (2,4GHz) in the "last mile" to the end users and interconnects with up to 20 miles long "802.11a" 5-6GHz links... The first steps for this net is more than 6 years old!

All over Denmark farmers are building their own infrastructure using cheap standard wireless AP's (~ $50) and "cantennas" or homemade biquad's that may be produced for less than $20,-

Infrastructural links cost a bit more but it does not matter... There are many users to share this investment!

Everything is hooked up to fiberconnections where this is possible and all users experience a broadband connection on 512-2048kbps - not bad!

This smells like "yet another 802.11n pre-release" or the fantastic story of Microsoft inventing security...

Too late.... Tooo bad!!!

Where were You (Intel) when this all started?

Uganda? We already help down there by sponsoring equipment (<a class="jive-link-external" href="" target="_newWindow"></a>) simply use a LinkSys WAP11 in a can and attach an antenna...

In Costa Rica they use the same method to interconnect the entire country:
<a class="jive-link-external" href="" target="_newWindow"></a>

Show us something new for a change!!!
Posted by ni3ls (1 comment )
Reply Link Flag
Some questions
First off, WiFi is a FCC "section 15" technology, I am guessing they are not using this in the US because they are using transmitting with more power than is permitted by section 15?

If this is the case, the FCC licensing requirement for WiMax matters not in these countries anyway.

If they are in fact still within section 15 guidelines, why bother?

As a ham tech I know as well as anyone that using excess transmit power in situations that can be solved with superior engineering, but if needed to build a wireless network in a rural area of a 3rd world nation with limited resources I would throw a high power amp on my transmitter just as fast as you can say spark gap.

Additionally, 2.4 and 5.8 Ghz isn't that well suited to long distance communications in the first place.

It is not like this thing is going to be communicating with laptops because they wouldn't be able to transmit back to it anyway.

Since all you are creating is a point-to-point link to another device much like it tie one hand behind your back by not using a lower frequency with less attenuation in the first place?

At the end of the day, the cost difference between building a transmitter for 2.4 Ghz and one for 250 MHz is essentially moot.

I don't want to discredit their research though, the "steerable" technology behind it hold merit and isn't necessarily restricted a any specific frequency or transmit power.

I just don't think it would be all that difficult to run WiFi on 50 or 250 MHz.
Posted by Dachi (797 comments )
Reply Link Flag
EtherLinx has had 50+ mile WiFi since 1997
N.Y. Times
2 Tinkerers Say They've Found a Cheap Way to Broadband
June 10, 2002

Telecom: Is Wi-Fi the missing link?
By John Borland
February 4, 2003, 4:00 AM PT
Posted by Layne Holt (4 comments )
Reply Link Flag
where can i get it....
Posted by lookyinfo1004 (1 comment )
Reply Link Flag can be used for scanner and access point
Posted by wlandhiraj (3 comments )
Reply Link Flag

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