What is WiFi channel width?
Channel width basically controls how broad the signal is for transferring data. Think of it like a highway. The wider the road, the more traffic (data) can pass through. On the other hand, the more cars (routers) you have on the road, the more congested the traffic becomes.
By increasing the channel width, we can increase the speed and throughput of a wireless broadcast. By default, the 2.4 GHz frequency uses a 20 MHz channel width. A 20MHz channel width is wide enough to span one channel. A 40 MHz channel width bonds two 20 MHz channels together, forming a 40 MHz channel width; therefore, it allows for greater speed and faster transfer rates.
Obviously, two channels are better than one, right? In theory, yes. But not if those channels are crowded with noise and interference. In crowded areas with a lot of frequency noise and interference, a single 20MHz channel will be more stable. 40MHz channel width allows for greater speed and faster transfer rates but it doesn’t perform as well in crowded areas.
However, noise and interference is not always the issue. Sometimes it’s the distance. If greater distance is the primary objective, my preference is the 2.4GHz band.
If you discover that all of your neighbors are using the 2.4GHz band and your wireless performance is unreliable, first try changing the channel. Channels 1,6,11 are preferable for the 2.4Ghz band.
If after changing the channel, your connection is still unreliable, you may find it beneficial to “get away from the crowd” and use the 5GHz band. In the following image (still using the inSSIDer software from MetaGeek.net) you’ll see that on the 5GHz band I’m all alone. There are no other wireless SSID’s in the area.
Therefore, even if 5GHz isn’t as strong at penetrating obstacles, the link quality is excellent because I’m the only one broadcasting on this frequency. This is like traveling on an open highway that no one else is using.
For my particular situation, the 5GHz band provides a more reliable connection. Not to mention that I had 25 neighbors trying to share a handful of preferred channels on the 2.4GHz band. Granted, the range is not quite as far with 5GHz but it is acceptable throughout the entire building.