Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm having issues getting consistant wifi working in my office. We are in a highly built up area with lots of office blocks around us. I know i should change the channels to e.g. 1,6,11 or something similar but what other options do i have. 2 of the access points can see around 30-40 neighbours with more than half giving 50-60% signal.

What effects will

increasing the power of the access points

or what if i decrease the power?

Or what should i try?

I did setup 5ghz which solves the problem but a lot of devices don't have 5ghz so the problem is only solved 50%.

share|improve this question
"I know i should change the channels to e.g. 1,5,11 or something similar" "Or what should i try?" – ceejayoz Apr 16 '12 at 21:30
I've done that and helps for a bit till 10 other access points end up on channel 1 and that access point practically dies. – user112570 Apr 16 '12 at 21:31
Are you noticing that when you change your channel or name on the Access Point, new APs appear on that frequency as well? As if something was following your AP? – JohnThePro Apr 16 '12 at 21:43
well the problem i have is its almost like whatever channel i choose there will be atleast a few different access points it can see on the same channel with decent signal :( so it makes it harder to choose where to put each channel as its like a choice of 6 ap's are on the same channel in this area or 7 over there. – user112570 Apr 16 '12 at 22:01
"Switch to 802.11n and use the 5GHz band" -- not viable for everyone, but if it could work for you it's way better than staying in the hopelessly polluted 2.4GHz spectrum. It's a cesspool down there! – voretaq7 Apr 16 '12 at 22:19
up vote 3 down vote accepted

I have a few solutions for you, most of which can be utilized together, but some require hardware and software solutions.

Identify your biggest WLAN & other interferers

-walk around with a spectrum analyzer or Wireless tool

-identify the source

-use a directional to locate the offenders, for use with below solutions

-identify any other devices that may be operating in the same frequency ranges, or similar ranges, such as microwaves, specific wireless phones (not cells), lights, Zigbee, wireless video cameras, bluetooth, or other.

-identify which channels they operate on

Channel alteration

-change channels

Increasing the power of your WAPs

-add an amplifier

-use a WAP with more power output

Increasing the antenna gain of your WAPs

-add a high db antenna

-use an antenna with a footprint tailored to your clients

Increasing the power of your clients

-use higher power WLAN NICs

-alter the transmission power of your WLAN NICs via settings

Increasing the antenna gain of your clients

-use WLAN NICs with higher gain

-use external antennas

-use tailored antennas tuned to the type (omni, yagi, etc)

Blocking interfering RF / Replace interfering devices

-use RF blocking paint

-use RF blocking wallpaper (copper sheath, etc - google "faraday cage wallpaper" for samples

-identify other faraday cage options (there are several).

-if you identified any devices operating around 2.4 in the identification step, consider replacing them, or blocking them at this point.

Identify vendors specializing in RF saturated environments

  • Some vendors like Cisco's Cleanair product line, and others sell products meant specifically for high RF environments like your own. You may be able to do a WAP and client swap in order to help with the situation. They will also offer loaner equipment for you to test out in your environment.

Better placement of your WAPs

-use some wireless auditing tools to determine strength

-use some tools (vendors provide for free or use google) to come up with alternative locations

-test alternative placements

There are companies that a wireless survey including much of above for around $3,000 to $5,000 US but I would save the cash and do it myself.

share|improve this answer
This is good advice. Thanks. If i increase the power, will the surrounding networks just not increase the power also? Currently i have power on 40%, should i increase gradually and see performance changes or just go for 90 or 100% ? – user112570 Apr 17 '12 at 15:19
The surrounding networks will likely remain static. An increase in power could help with your situation and it would be one of the comparatively easier, and cheaper fixes. Some of above solutions (e.g. faraday) can be pricey! – Brennan Apr 17 '12 at 15:52
Ok thanks for your help – user112570 Apr 19 '12 at 10:49

Use Inssider to find a channel that is not in use, remember that there will be some overlap (this is why people say use 1,6 or 12).

Increasing the strength or amount of AP's you use will help you over power your neighbors... By blasting even more RF around your home :)

share|improve this answer
There's a lot of overlap. – Joel Coel Apr 17 '12 at 1:58

Depending on your Country, you may try to use Channel 13 & 14. As not allowed in every country, they are more likely to be less crowded.

Also, you could go for a 5 GHz Link to the exact place where the network is needed, and connect a 2.4 GHz AP with low power Wifi to connect your devices without 5 GHz. As the distance is reduced, interferences from other networks might be lower too.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.