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New WiFi Link Distance Record
Espectr0 writes "A Venezuelan professor along with his team have set a new record for the longest WiFi link. Using commodity hardware, they established a connection between a PC in El Águila, Venezuela, and one in Platillón Mountain, a distance of about 237 miles. The previous record was 193 miles. Slides [PDF] are also available."
One of my ex-housemates was a Sonar tech in the Navy. The Sonar and Radar guys apparently hang out together on those ships and one of their favorite games was to paint the guys coming up the desk with an armload of flourescent tubes with the radar, illuminating the lamps. Hilarity ensues. They never killed anyone doing it. But at close range and high power, I'm told you can throw hot dogs up into the path of the radar and they come down cooked.
Moral of the story is that it's directional and as long as you don't stand in front of it there's not likely to be any significant effect. At the other end, the signal has been scattered substantially and it's only coming in at a whisper of the original signal.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
A friend of mine who's a military history buff told me a story about Soviet fighter aircraft in the 70s and 80s. Seems they had very powerful look-down, shoot-down radars and pilots were instructed to turn them off during take off and landing. Apparently sometimes they forgot, and runway maintenance crews had to regularly pick up the carcasses of rabbits, birds and other unlucky critters that were in the area when those MiGs went on missions.
Quantum mechanics: the dreams that stuff is made of.
and a parabolic, and various amplifiers... and this:
They never said how they accomplished that, but it was presumably done by hacking the firmware to change the collision detection and the back-off settings.
A colleague of mine was a submariner who had this story. They were down for an extended dive, and when they surfaced, they would send a short, dense burst of communications and data on a very powerful microwave uplink - get up, send fast, get back down. It was a very powerful signal - and they would surface to a depth that would get the periscope and the antenna above water, do a quick scan for surface vessels, send the burst and dive. One day they did this and saw thru the periscope there was a gull on the antenna mast. So they would dive to submerge the antenna, the bird should fly away. They resurfaced, and the bird perched on the antenna. They did it again. Bird comes back. Third time. Fourth. Can't shake the bird. Finally the OD tells them "punch it" and send the microwave burst signal. He said the bird just keeled over and dropped into the water.
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
let me also share this record (announced also 24 may in in this Italian newspaper): the Ixem team of "Politecnico" in Torino has set up a 20megabit connection from "Capanna Margherita" (Mount Blanc, 4556m of altitude) with "Pian Cavallaro" (a point on the mountain range that divides Tuscany from Emilia-Romagna); the two points were 295km apart; the hw used was a 386 CPU running Linux; the network is Hiperlan type 2 and Wi-Max 802.16 (EIRP regulatory requirements limited to 30 dBm is satisfied). They have also set a webcam in Capanna Margherita, that is accessed thru the link