Since the advent of Wi-Fi many years ago, a good number of us would use some form of it in our homes and workplaces. You would be hard pressed to find a laptop or decent smartphone without Wi-Fi and many ISPs provide the option of receiving wireless router modems (if not already the default option).
What most wouldn’t realise is that there is limited spectrum on the 2.4GHz range for use by 802.11b, 802.11g and 802.11n devices. Furthermore, a lot of other wireless devices share the same unlicensed spectrum, including but not limited to:
– Bluetooth devices,
– some cordless telephones,
– wireless AV transmitters.
So why is this a problem?
Imagine you have a long pipe and you spoke to someone through it. That arrangement would work fine as long as you worked out who spoke and who listened at any given time. You could have a group of people on each end having a conversation with each other but the effective speed of each one of those conversations would slow down as you added more people.
So when someone next door could use a different pipe for their conversations but starts talking down your pipe instead (and probably outside of your control) your conversations end up taking longer because of interference from your neighbour. Time is wasted by asking people to repeat themselves and further aggravating the issue.
So what is the solution?
Where possible, assign your wireless device groups to different non-overlapping channels. Essentially, this means channels 1, 6 and 11 for Wi-Fi devices. You might need to work out the channels used by neighbouring Wi-Fi networks and signal strength to work out what is best for your location. NetStumbler or WiFiFoFum are handy applications that can help you scan for networks. Other devices like AV senders or cordless telephones might have a little switch underneath to set the utilised frequency. You might need to check the documentation for specifics if they aren’t already labelled.
Otherwise, if you aren’t using a wireless device then switch it off where possible. Fewer wireless devices broadcasting means faster speeds and lower contention for everything else on that spectrum.
You might also have high draw devices with an earth leakage or internal fault that could also cause interference (like fridges when the compressor kicks in). You might need to do some sleuthing in these cases to get to the bottom of your problems though (so try turning everyhing off in the house and swithing back on one by one until you find the problematic device).
Hopefully this has given you a basic understaning of how wireless devices can compete for finite spectrum and how you can make most effective use of it.