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A DIYer's Quick Guide To Cheap Wireless Extension
An anonymous reader writes "This piece is described in one of the comments on it as 'a little piece of genius'... and I have to agree! Although Peter Cochrane seems a bit of a crack pot, the ways that he comes up with to get connected when he's out of range in the sticks are pure genius and he makes them appear really simple! Think old satellite dishes, USB dongles and plastic bags and you'd be on the right tracks to upping wi-fi signal by 4 bars." A perfect excuse to link to one of my favorite sites, if you want more details and photos on similar jury-rigged long-distance connections. However, your meterage may vary — I've found USB Wi-Fi devices to be pretty fickle under Linux, with some distros working way better than others.
Wouldn't it be nice if this technology was used to make a free citywide wireless internet? We just need a bunch of people with this ambition and it could be done. I once read a book, called When A Strange Comes To Town, in which some people had the same ambition. You can get the book from Project Gutenberg if you look around. It's a newer book that has never been copyrighted.
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www.usbwifi.orconhosting.net.nz
Check out.
I found this great instruction on Instructables (pops new) on how to create a usb wifi out of a 2.00 strainer from WalMart. Works like a champ!
My friend lives across the Ohio River and we're able to send the signal across the river that way.
Dont forget Pringles cans.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
I am one of those long-time WiFi zealots, and it is clear to me that people just don't want free ubiquitous wireless internet -- or they just don't care.
Here in Pittsburgh, there is occasional talk of some group trying to do this. There have been some people who have received funding, but they waste it, and their project evaporates. Between ten and twenty (or more) companies start off here, and either fade away, or move to some other city. telerama, hobnob are the two that stick out (for which I remember URLs to).
Largest public network here is run by ONE GUY who just went and built it himself, Shadyside WiFi.
Otherwise, there is chatter on some of the local lists, but by and large, nobody wants free city-wide wireless Internet. Just me.
Zhrodague.net - I do projects and stuff too.
10 years ago you might have had to improvise, but today you can get cheap high quality antennas and amplifiers that is a lot better than a USB dongle in an old satellite dish.
My favorite source is http://www.hyperlinktech.com/
and you can do your link analysis here:
http://cgi.gbppr.org/wireless.main.cgi
If you really need big distances, you can use an old 12' sattelite dish, but otherwise stick to the formula above. It will save you a lot of time and trouble.
I have reliable links over 10km with 10mW running at 50Mb/s
don't cut it off www.mgmbill.org
It's not that easy - and you might be better off just buying a cheap unidirectional antennae I live in a rural community and a 3G USB dongle several months ago. The low signal strength meant I was on the slow end of the speed for 3G. I tried the exact thing he did, but tried some other options as well. First, I purchased a $50 unidirectional antennae. That improved my signal strength by 10db. That was enough to get me to the range of 1300 down and 400 up consistently, with full "bars". So then I unplugged the antennae, added a couple of active USB cables, and put the dongle on the roof (1 story up). That improved my signal 5 db without the antennae, and 3 db with the antennae. So now I had improved about 13db. Finally, I grabbed my old dish, and aimed it at the cell tower. Then I put the dongle in place of the amp unit. Please note that most dishes have offset amp units, so you dish looks like it's aimed "below" the tower. It helped several decibles. I replaced the unidirection antennae and put in the dishes sweet spot, and it got me nothing more. Short version - I was better off elevating the dongle and attaching a cheap unidirectional antenna than I was playing with the dish. I suspect that will be true of most who play around with this. Final note - I have experience making other antennas - AM, FM, etc. I can assure you it wasn't lack of knowledge that prevented any huge increase in signal when using the dish.
A link to an old writeup from one of my favorite professors: http://people.wallawalla.edu/~Rob.Frohne/Airport/Primestar/Primestar.html
Also, ditto on the !news.
I've been looking into a similar setup. You need multiple wireless adapters and a load-balancing utility.
http://forums.remote-exploit.org/archive/index.php/t-7419.html
A quick and dirty way to do it with Linux iptables:
http://tetro.net/misc/multilink.html
My goal is to create a monster wardriving setup for constant on-the-road connectivity.
"When information is power, privacy is freedom" - Jah-Wren Ryel
It's jerry-rigged, not "jury-rigged," dammit!
Actually, it is "jury-rigged".
I suspect these antennas are typically aimed at much lower frequencies (say HF/VHF), and require a ground plane. The reason why I think so is that for (super) high frequencies, antennas are mostly self-contained (one piece you can attach to a pole) and don't require a large garden and poles and the like.This is not the kind of structure you use for pleasure, but because you have to (at low frequencies).
It's getting easier to use USB WiFi adapter with linux lately. Linuxwireless.org has done some great work with the re-written modules, which are included in the recent kernel version. And some companies are paying attention. I've been using the Wi-Fire for long range wifi for a while, and hField Technologies just released a Linux Version, which I've had no problem with on my Suse or Fedora machines.
There are EIRP limits. Basically you can't legally use a directional antenna to improve the signal on the sender side if you're already at the EIRP limit. The only benefit of the directional antenna in that case is that you can lower the emitter power and don't pollute the unused directions with your signal. To establish long-haul wifi connections legally, you need directional antennas on both sides to boost signal reception, not emission.
I suspect these antennas are typically aimed at much lower frequencies (say HF/VHF), and require a ground plane. The reason why I think so is that for (super) high frequencies, antennas are mostly self-contained (one piece you can attach to a pole) and don't require a large garden and poles and the like.This is not the kind of structure you use for pleasure, but because you have to (at low frequencies).
There wouldn't be any reason why this would be worse at high frequencies than low frequencies. I could envision making a printed version of this on a very thick PCB and using the bottom copper cladding as your ground plane. Heck, a sheet of aluminum foil could probably do it in a pinch. The ground plane size at Wifi frequencies is not very large. I would guess the main reason that people haven't done this is why bother? The short wavelength of 2.4 GHz compared to everyday length scales means that it is easy and space efficient to build simple antenna arrays. In addition, you can easily create the antenna array as a printed antenna further simplifying the build process. With the rhombus though, you're talking about an antenna footprint of several wavelengths, like 8-12 as the OP stated. Why bother having such a large footprint when you could easily make a simple printed antenna array with spacings of sub-wavelength between elements? Or, if you are just a garage enthusiast, a waveguide or reflector antenna provides excellent gain. A parabolic dish requires minimal assembly and gives you 10's of dBi in gain.