Prevent Interference From Other Wireless Networks
The wireless signal range in standard 2.4GHz wireless routers is divided into a number of channels. There are 11 channels (1 to 11) available for wireless signals in the US whereas the UK and most of the world have 13 channels (1 to 13).
Without going into too much techie detail, only 3 of these channels do not overlap or interfere with each other and therefore provide a good strong signal – channels 1, 6 and 11. Most routers are preconfigured ‘out of the box’ to use one of these 3 channels.
However, because there are only three good channels to choose from, there is a high chance that a neighbor’s router may be using the same channel as yours. This could cause interference between both routers – and make your wireless connection slow or unreliable.
To avoid your router ‘clashing’ with others, it is a good idea to scan for nearby wireless networks and see which channel they are using – then change your router to use a different one. E.g. if nearby networks with a strong signal are using channels 6 and 11, then you should choose channel 1 for your own wireless network. It is easy to scan for nearby wireless networks either in Windows or using a free Android app:
Windows – The tiny program WirelessNetView is available from Nirsoft here as a standalone (portable) version – just scroll down the page to ‘download it in a zip file’, unzip the contents and run the WirelessNetView program (NB you must run it on a computer with working wireless capability e.g. a laptop/netbook in order for it to detect wireless networks).
The program detects any wireless networks nearby and shows you the Channel used and the signal strength etc as shown below:
Scroll to the right of the program to see the wireless Channel that each network is using – if one of the 1, 6 or 11 channel numbers is free you should use that one for your own wireless network to ensure there is no interference.
Android – The free app WiFi Analyzer available here is a similar program for Android which shows the wireless networks around you, including the Channel (CH) being used and the signal strength (green bar):
Again, this helps you find a less crowded (hopefully empty) wireless channel which you can allocate to your wireless router.
What If Nearby Networks Are Using All Three Channels?
You will have to share a channel with at least one of the other networks – but which one? The answer is to share a channel with the network that has the lowest signal strength – the lower the signal strength, the less likely it will cause you interference.
If there are multiple strong signals using all available channels (e.g. in an apartment block) and causing major interference then you have to consider whether you would be better off using a faster and more stable wired network instead – using powerline adapters to cheaply extend internet access around the home is a great solution if you can’t run additional network cables between rooms.
How To Change The Wireless Channel On Your Router
Now you know which is the best channel for your router to use, check if it is already using it. If not, change it – see ‘set up a cable router‘ for an illustrated guide if you have a cable router, especially the ‘Wireless Network’ section in Step 5.
If you have an ADSL router see ‘set up a ADSL router‘, especially the ‘Wireless Network’ section in Step 4.