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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.
www.linux-skunkworks.com
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!
Karma: Marginal (mostly due to the border around the website)
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.
Lots and lots of tinfoil... around the walls of the apartment of course, not your head.
--
This sig is spel cheked
This has the added bonus that all us tinfoil-hat weenies know about! Make sure you line the ceiling as well, or the spy satellites will get you.
*meep*
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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Lining the walls with lead...
Sig!
nuff 'said
Wireless may be cleaner and less involved when it comes to physical setup, but wires "just work" after you've strung them (unless you've miscrimped them, you poor soul :-). There's no messing with channels, positioning antennae, or worrying about outside interference, as there is with wireless.
If you've ever been to a LAN party where lots of people have wireless keyboards and mice, the advantage of wires is apparent. Instead of having to deal with the noise and lag caused by all the wireless cross-talk, you can glide effortlessly through the map, fragging people as you please.
As far as actually wiring the room goes, there are lots of ways to run cable without having to actually drill holes in walls or otherwise disfigure the building. You can sneak them along the baseboards or up through drop-tile ceilings (though you do have to deal with conealing drop-down points when running cable overhead).
Like I said, this may not be practical in your case, but it is worth mentioning.
that that is is that that is not is not
You live in a NYC apt and a 3ft ethernet cord doesn't cover your entire apartment? wow...
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).
As you note, the wireless spectrum is a shared resource, one that it's *very* difficult to eliminate abuse of.
The problem is, the wireless spectrum falls prey to the public good problem. It's in everyone's benefit to try to outpower the others, and as a result, nobody can get through.
Wireless devices simply profliferate. There are few areas that are going from wireless to wired, and more and more people are picking up wireless devices.
Spread spectrum devices have been getting more popular for some applications, because they are more reliable and give a better signal. However, they pollute the spectrum even worse, causing interference over a broad range of devices.
It reminds me of cable modems. When they came out, they were a great deal. However, in any areas where they've gotten popular, they give awful performance. There are just too many people trying to pile on to one shared resource.
The only remotely convincing argument I've seen from wireless advocates is that signal processing will improve and give better performance (up to a limit). Unfortunately, there are plenty of legacy devices out there that blast out much stronger signals than they need to. These keep more sensitive devices from using the spectrum.
I avoid wireless devices. I use wired Ethernet, wired mice, a wired keyboard, etc. The performance of wireless is only going to go down.
May we never see th
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.
Some cards simply aren't going to work well in your environment with your router. Try using a few different cards, and if that doesn't help, change the router/ap. Use an AP and a regular cat5 router instead of a combo (consumer wireless routers are the cheapest of the bunch).
Also try using a B router/AP with G cards. You'll find that the G cards connect to a B router better than they connect to a G router and better than B cards connect to a B router.
Lastly, pay attention to the antennas. Place the router in a central location at about the same height of the receiving cards. Make certian you are using a router/AP with two antennas.
Find a free channel and go for it.
Increasing the power of the router may not help if you cannot also increase the power of the cards, not to mention that it often degrades the signal. Using directional antennas will cause problems with multipath interference in your building.
The phone intereference is annoying, but a good card and a good router/ap will be able to downgrade the speed without dropping the connection.
And remember, there's nothing worse than a box of spilled packets all over the floor. Don't up the power.
-Adam
I stream mp3's throughout my apartment using a wireless ethernet bridge for both my rio receiver and qcast on my playstation2. I would get occasional dropout and random times which I attributed to neighbors, and could almost guarantee a dropout when I used the microwave which is located between my router and stereo. I have 802.11b equipment and dropped the bandwidth from 11mbs to 5.5 mbs. Guess what? I haven't had the signal drop yet.
at work we have about 40 microwaves.. at home my shed was just too damn far from the house..
look for a siemens powerline to wifi adapter. excellent... put an AP anywhere.
14mbs, and consistently too..
every day http://en.wikipedia.org/wiki/Special:Random
Hmm, I've been having irregular problems with my 802.11b dropping out. I live in a neighbourhood with houses on each side; guess what I am seeing is the interference described by numerous others here... someone microwaving, phoning or whatever. Most times it happens the system doesn't recover unless you power-cycle the WAP. This had led to me suspect the power supply to the unit, but maybe it just can't handle interference that wipes it out and a cold-restart is the only cure. FYI, I am running with SSID broadcast enabled and 128-bit WEP.