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DEFCON WiFi Shootout Winners Set A Land Record
bscience writes "While attending the DEFCON 12 convention this past weekend I had the chance to see the standing ovation a group of 19 year olds received for establishing a 55.1 mile unamplified WiFi connection!" A snippet from the Wired story linked there: "Mobile warriors having trouble making a wireless connection across the hall might want to give some Ohio teens a call. This weekend they were able to make a 55-mile Wi-Fi connection. ... They might have achieved an even greater distance, Justin Rigling said, "but there was no road left."" (Here's the post from a few weeks back about the competition.)
Because they didn't even max out the non-amplified distance. If you read the Slashdot blurb again it says They might have achieved an even greater distance, Justin Rigling said, "but there was no road left."
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
Omnidirectional coverage is a bit harder to expand. You can't really beat a 5/8 wavelength groundplane, and they're easy to make. (at lower frequencies anyway, not sure about ghz)
Not counting the ability to use amplifiers, you could think of wifi coverage as light... put a 100w lightbulb in a field at night and how far away can you be and stil read a book? Not very far probably... 30 feet maybe. Now, take that bulb and put it in a parabolic lens. Now you've got a 100w flashlight. If the flashlight is pointed your way, you'll get hundreds of feet. The better the lens and the sharper the focus, the greater your range. Come up with a more fundamental improvement (like a 100w laser?) and your range increases to a radical distance that could easily be miles. But it still doesn't help the guy standing 5 feet off to the side of the light though, he's in the dark.
Directional and omnidirectional coverage are for totally different purposes, and really can't be compared or mixed. There's no use in complaining about your omni coverage when people are making improvements in directional coverage - it's apples and oranges.
I work for the Department of Redundancy Department.
Wind doesn't really affect radio waves that I am aware. Solar Flares, on the other hand do, but their impact on this portion of the spectrum (GHz) is minimal. Get up into the 10meter or 20meter bands and a good solar storm can knock out the ability to transmit for hours or longer.
Not where I am, nor, after a little Google:
...
...
[google] define:hawk
The verb "hawk" has 3 senses in WordNet.
1. peddle, monger, huckster, hawk, vend, pitch -- (sell or offer for sale from place to place)
whereas "hock" though I would have given you it, appears to have a different meaning
The verb "hock" has 2 senses in WordNet.
1. pawn, soak, hock -- (leave as a guarantee in return for money; "pawn your grandfather's gold watch")
However, this mistake is as nothing to those who type "loose" when they mean "lose".
http://www.wsu.edu/~brians/errors/lose.html
no time, no sig
I believe it was $1500 in Gift Certs for the three of them. $500 for 3 catagories (Longest unamped, Longest homebrew antenna, Longest overall)
The also got oodles of wireless goodies.
Objects in the blog are closer then they ap
but in a home for rich people... multiple AP'
s are not a viable option as it doesn't hand off seamlessly.
There are some that do, model numbers escape me. Or it might be the card and software that automatically switches APs to the best one.
Not that I think it is necessary. I was able to get a pretty good 11Mbps (i.e. plenty good for internet) link where the AP is in the far corner of the basement and I was on the second floor. I think it would take a pretty huge house, or maybe one with concrete/stone/metal floors and walls to need multiple APs.
When we start talking about setting and breaking distance records using any type of RF, atmospheric conditions will undoubtedly play a factor. A phenomenon known as Tropospheric Ducting can redirect a short wavelength signal back down to earth, allowing further than line of sight communication.
While this would be great for setting communication record, it would not allow for long-term reliable communication.
Dan East
Better known as 318230.
Being a former Cinci resident, I was a bit curious about these guys, and google-stalked them . . .
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Looks like they all went to St. Xavier, a pretty well respected (in both athletics and academics) prep school.
Here's a picture of Ben when he was a junior, winning a theater award for sound production.
Meng's got a website here that's a bit outdated, but considering the projects were from his junior year in high school, rather impressive. Seems he was a HAM radio guy.
Running out of time, the first link I found for Justin Rigling was this link. One more connection to the guy, since I use to work for AK Steel. The little blurb about the scholarship does make him sound like a stereotypical geek (JETS, Science Olympiad, Robotics, Math, and Photography clubs, etc etc). A bit of a contrast to his sister. Not exactly what you'd expect from the son of a steelmaker . .
Okay, enough being a stalker . . .
As one of the judges, I can provide the GPS coordinates and you can use your favorite topo maps to determine if it is indeed possible. We will be putting up images and data on the contest page as well as www.adversarialsciencelab.net website sometime today.
WWJD for a Klondike Bar?
From QST magazine (http://www.arrl.org/news/stories/2003/12/10/3/):
"Amateurs complete 82-mile two-way DSSS link on 2.4 GHz: ARRL High Speed Multimedia (HSMM) Working Group member Ken Cuddeback, NT7K, reports that his students at Weber State University in Ogden, Utah, recently completed two-way direct-sequence spread spectrum (DSSS) communication on 2.4 GHz over a distance of 82 miles. The WSU students--which include one ham, Brandon Checketts, KG4NZV, and several prospective licensees--broke the current world record of establishing a wireless link on 2.4 GHz with DSSS (using IEEE 802.11b "Wi-Fi" protocol). "Please join me in congratulating Ken and his students on this fantastic accomplishment!" said ARRL HSMM Working Group Chairman John Champa, K8OCL. Cuddeback says his students used PrimeStar dishes with unamplified Cisco Aironet 350 cards in each laptop. "We set up a NetMeeting session and transferred a 2.5 MB mp3 file successfully," he said. The Cisco Wi-Fi cards run about 100 mW."
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
Actually, they were 30mw Lucent Orinoco cards. Impressed yet?
Ya I know, a 5/8 groundplane is not a very practical idea in the ghz range, though it's certainly possible. Critical tolerances at that point are well down to the 1mm and below range though, that would not be a fun project to undertake.
I want to play with http://www.rangeextender.com/224pagransy.html if I get the time someday. 24 DBI gain. I've recommended it to some of our customers, several of whom have bought one, and so far, everybody is quite pleased with them. One of these on one end (and a regular omni on the other end) will blast through building after building to get to the other base station. It's also fully weather-proof and built sturdy, unlike those pringles can jokes.
I work for the Department of Redundancy Department.