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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.
Does anyone know of any attempts to use Rhombic Antennas with WiFi? They're very simple and provide huge gain. Their typical downside is that the length of one leg needs to be 8-12 wavelengths, which means they're the size of a football field when you're dealing with most radio frequencies, but 2 GHz has a 0.15m wavelength. A point-to-point rhombic should easily fit on the roof of a house.
Not a typewriter
... my own comment, yesterday?
This isn't really new, there have been people doing this kind of thing for years. Check Seattle Wireless dot net for their experiences. I'm sure there are others.
Zhrodague.net - I do projects and stuff too.
Every year or so I hunt for a simple utility to allow me to connect to more than one wifi network simultaneously and boost bandwidth that way. Never had any luck. Anyone know if this is feasible or not? The apartment complex where I currently live has multiple secure wifi networks set up specifically for residents, plus a bunch of folks have unsecured ones based on local cable broadband they don't mind sharing. If there was a way to connect to all of them at once ... awesome.
A-Bomb
Humm so how you you send when your 500 M out of range. That's fine to receive any signals but screwed if you want to send. good idea but FAIL
Just tried on my balcony: WiMax box in front of old sat dish = ~ 30% higher transfer rate!
I rarely do this, but this AC is making the only point that needs to be made here. My own home router could comfortably serve a block of my neighborhood including the nearby park (I tried) but I'm not going to open it up because under US law I will go to jail if someone uses my open WiFi to download childporn or some such.
The cost to me would be minimal and I'd set the QOs such that the freeloaders wouldn't interfere with my own activities -- and if everybody did that, we'd already have free ubiquitous wifi in all cities in the US. Because there's always some server around somewhere -- it's been forever since I truly got a "NO networks found". They're just all locked down like crazy because of the absurd US laws that hold a communications provider (me!) responsible for what clients do with the services they provide for free out of the goodness of their hearts...
We're all born with nothing.
If you die in debt, you're ahead.
Why use a unidirectional antenna with a dish? The dish focuses a wide beam (eg 45 deg) at the amp to a narrow beam (eg 1 deg) at a distance. The unidirectional antenna is already radiating at a narrow beam, so the dish will basically be a flat mirror for the signal, which will not help at all (as you noticed).
You should try with one or the other, not both.
Allow me to clarify, then: Discussion of novel "free" services makes me nervous.
Every "free" (meaning, of course, tax-supported in one way or another) service I could possibly want, and a great many more I believe should not be "free", are already provided by my current city.
cogito ergo dubito
Sorry, but this really isn't news. Hell... even *I* have done this, which means that it can't be anywhere near the cutting edge. :P The concept of putting a cantenna or bi-quad at the focal point of the dish has been out there on web pages for years. I fitted *my* dish so that I could interchange a cantenna or a USB dongle as the need arose.
The advantage of the USB dongle is that you don't incur the line losses of the antenna cable if your laptop/PC is a long way from the dish. You can get around the problem of USB cable-length limitations by using some nifty USB "extension cords" which are basically a long USB cable with a 1-port hub at the end.
I will add one thing that I haven't seen on any pages, however. Most satellite dishes have the arm positioned away from the centerline axis of the dish... usually below it, which must be accounted for when aiming. For example, if the arm holding your dongle/cantenna is 10 degrees below the centerline of the dish, then you'll be receiving signals from whatever is 10 degrees above the centerline. It's the same concept as flat mirrors... angle of reflection equals angle of incidence.
Why does this matter? Well, if you are trying to communicate with a station that's at relatively the same elevation as you, then you're going to have to point the dish down toward the ground a bit. This can be very conspicuous... especially if, ahem, the other station's owner doesn't know you're communicating with them (cough, cough). The best solution that I've come across is to turn the dish upside-down so that the arm holding the dongle is on top, which allows you to point the centerline of the dish skyward again, so that it looks more like the other dishes in the neighborhood. Almost nobody will notice that the arm is affixed to the top of the dish rather than the bottom... and even fewer will grasp the ramifications of it.
Saskatoon Saskatchewan Canada has free citywide internet. It's slow as a dog during the day but quite usable at night for basic browsing/emailing etc. Great for us touring musicians!
Here is another smaller scale hack using a metal strainer/steamer as a collector.
But a satellite dish will only help the reception, not the access point on a city-wide basis, so it's benefits are limited. However, it might give hope to cottagers where wifi is close but not quite.
What the article describes as going from zero bars to five, sounds like range extension by a factor of at least five, so let's use 100m as an unmodified standard range, that's about 1/16th of a mile.
It would also help by almost as great a margin to have a small reflective dish in front of the transceivers to direct forward signals back into the larger dish (a forward collector), or else most of the transmission will travel away from the intended target. That strainer hack would be about the right size for the job, perhaps too big, but imagine that facing back into the satellite dish, directing emissions out the larger dish in a straight line. That should boost the signal strength up by at least another 80%, so call it 9x range extension.
The same improvements would apply at both ends, so by my math, a well-configured line-of-sight array with dishes and forward collectors at both ends should achieve at least 18x range extension, definitely over a mile.
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