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WiFi Interference Problems in Urban Environments?
EagleEyez asks: "We're running a wireless network (802.11g) in our apartment: four computers connecting to a Linksys wireless router. But living in a high-rise building in a major city (NYC) there are at least 3 other wireless networks nearby, plus numerous microwaves and cordless phones in the apartments around us -- all of which make the wireless network less than stable. We've pumped up the signal strength on our router, but we lose the connection from time to time disrupting our internet connection and LAN games.
What other options are there to help ensure a consistent and reliable network connection? We've tracked the channels the other networks use and chosen one that doesn't conflict, but there's little we can do to prevent the interference from cordless phones, in other people's apartments. As more and more people go wireless, especially in denser urban areas, there has to be some sort of solution..." If you've run into this problem before, did you find any way to solve (or at least mitigate) the outside interference?
I use 802.11a for my wireless network and never had any problems with it since it don't get interface from other wireless or raditiation crap like telephone, microwaves and such.
-- Amazing how the Internet still humms along.... -- Dispite all the flaws of Micro$oft in their software!
Consider lining the walls of your apartment with aluminum foil or aluminum window screen (don't use the fiberglass stuff). Be sure to ground it well and install it in accordance with all FCC regulations and local building codes.
Hope this works for you!
Unknown host pong.
Aluminum foil wallpaper! Stylish and functional.
This "troll" makes an excellent point. Wireless has its benefits and drawbacks, and especially in an urban environment the drawbacks are enormous. Something as stupid as a neighbor's leaky microwave oven can drive one to tears. A wired ethernet connection is faster, more reliable and more secure.
I have a similar problem, but due to SBC giving out free wireless hardware to people that don't need it. The only success I had was when I decided I would just out power everyone else. I picked up a pair of 7db gain antennas, smacked one on my AP and the other on my laptop. I then switched to channel 9, nothing seemed to be using that channel. While it's not the most friendly, It works. Unfortunatly, the next step involves an op-amp and figuring out a way to insulate my toaster.
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This might be relevant only for b, but using channel 11 will considerably reduce interference from cordless phones. I'm assuming it applies to g also.
Wil
wiki
The answer, of course, is to sell your wireleess router on eBay, and start sucking bandwidth off of your neighbor's connection. The more people who do this in the building, up to a point, the less interferance you will have.
Problem solved!
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I have an apartment in Houston and I pick up at least two other wireless networks. I'm using 802.11b and what helped me was plugging my wap (linksys wap11) into a long cat5 cable and an extension cord. It turns out that I get better coverage with my wap off to one side of the apartment then in the middle. The signals bounce thru walls in ways you don't always forsee. Don't forget to try out each location with your microwave and cordless phones in use. I see a much more noticable difference with placement then I do with channel changing or even hacking the signal stregth.
My Hello World is 512 bytes. But it's also a valid Fat12 boot sector, Fat12 file reader, and Pmode routine.
Try using directional antennas on your AP. I don't know how your appartment is oriented, but you could try putting it into a corner and using something like a parabolic or yagi antenna directing it into the rest of the appartment.
If interference is still a problem, try a 802.11a AP. It opperates on the 5.8ghz spectrume and is less likely to have consumer products interefere. The downside to 802.11a is that you will lose distance; so hope your walls are like paper or buy a repeater for each room.
I don't have much experiance with a crowded spectrum, but I do know 5.8 has horrible range (which will lead to less interference from distant neighbors)
Urgo: "I want to live. I want to experience the universe and I want to eat pie!"
Jack: "Who doesn't??"
"We've pumped up the signal strength on our router, but we lose the connection from time to time"
Quite probably other people are doing the same. All of a sudden the spectrum becomes unusable because a couple people decide to blast the hell out of it with excessive power. It's quite easy to pack in a good number of WiFi devices if you follow proper WiFi etiquette
The best course of action is to only use the least amount of signal necessary to get a stable connection & use directional antennas. Directional antennas cause less RF pollution and interference with the rest of the spectrum and when properly aligned give you much better signal to noise ratios. Errant signals from sources not in line with the antennas are rejected much better and your signal should have much less interference.
Using amplifiers isn't the way to a better WiFi world.
given the option, I'd borrow a spectrum analyzer, and have a look see at what else is going on. turn off your router and let the spectrum analyzer sit on peak hold. often you'll find that the channel(s) you were trying to use were either
;)
a) in use, or
b) taking a lot of interference from external factors (like microwaves)
if you can't find a free channel, first step is to stop it at the windows. try and position your router without a view to the outside -- pagers are notorious for sideband splash on their 1000 watt transmitters.
... unless of course you don't work for a wireless telecom provider or don't have access to a nice IFR otherwise
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This might be off-topic. I can hear my Linksys WAP11 (802.11b) during heavy file transfers with my bone conduction hearing aid when I am in close range. It is the same type of interferences that I get if I am near radio stations or cellular phones. I believe this situation is going to get worse. I love wireless, but there are conflicts.
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
One solution might be to build power control into these devices. My CDMA cell phone constantly adjusts its transmit power level to the minimum needed to maintain the RF link at an acceptable BER (bit error rate). Besides prolonging battery life, it allows more cell phones to operate in a given area.
Mea navis aericumbens anguillis abundat
work with your neighbors. Find out who has these devices, have everyone lower their power, and configure the same security. Then use roaming (ipv6 does roaming better than ipv4) for your needs, no matter where you are.
And get everyone to drop their power, so long as every part of the apartment is covered what do you care which network you reach.
As for the phones: unless you can knock them off there isn't much to do. Suggest to everyone who has on that a cell phone is easier to use, and perhaps you can solve the problem the easy way.