WiFi is not a perfect network, it breaks down, it drops, it is slow, etc. On some occasions, this may be because the router is poorly positioned or not very powerful, the antenna of your mobile is malfunctioning or, quite simply, it is experiencing interference. In fact, it is very likely that this is the cause and that the root of the problem lies in the channels.
We are going to look at what the channels are, how to know which uses our router, which ones suit us best and, of course, how to change everything directly from our Android device.
WiFi channels and interference
Here are all WiFi channels. As you can see they all overlap.
Let’s start with the basics. The vast majority of WiFi routers broadcast in the 2.4 GHz band, which is the classic band and with which all mobiles are compatible. This ranges from 2412 MHz to 2472 MHz and is divided into 13 channels. These 13 channels share 100 MHz spectrum, but each has 20 MHz, so if we do the math… they don’t come out. Unless the channels overlap, of course.
This is exactly what is happening. The channels overlap, so each channel occupies part of the spectrum of the underlying channels. In the image above you can see it more graphically and the clearest example is channel 1, whose bandwidth reaches channel 3. This means that a router broadcasting on channel 1 will generate interference with a router broadcasting on channel 2 and another broadcasting on channel 3, and so on with everyone.
Interference is generated, above all, by overlapping channels
One possible solution is to switch to the 5 GHz band, which is less congested because it has 25 non-overlapping channels and capacity for higher speeds (albeit less extensive), but not all routers can stream to this band, especially the old ones. . . In addition, not all mobiles have an antenna compatible with the 5 GHz band, so it is not a solution, let’s say, universal. What are we left with then? Change channel.
Before changing the channel, we must know which one we are using
In the picture, all the routers broadcasting around us. Ours is marked in red.
And what channel should you switch to? The least saturated one, of course. To find out what it is, you can use a completely free and well-known application on Google Play called WiFi Analyzer. This will show you all WiFi routers broadcasting near you, their power and the channel they are using in a graph.
The graph will show you all the routers broadcasting around you and help you know which one is best for you.
As you can see above, we have countless routers broadcasting on our same channel or overlapping with us, which can cause interference, drops, speed reductions, etc. With this information we have enough to change the channel, but we can go further.
If you swipe three times to the left you will access a ranking. Click “Choose your AP” and select your WiFi network. It will show you which channel you are currently using and which one, based on those around you, you should switch to for the best connection. 14 will still offer all stars, but it cannot be used. In our case we are using 4 and would be interested in moving it to 14 (which we cannot), 13 or 12.
And now we’re changing it fast
Changing WiFi channels is as easy as accessing the router.
We already know the optimal channel, so it’s time to change it in our router. To do this, open any web browser, either on your mobile or on your computer, and type in the address 192.168.1.1. It will ask you for credentials which, if you haven’t changed them, are probably admin/admin, 1234/1234, or a combination of both.
Most routers are configured to choose the channel automatically, and this is a recommended option.
Now it will depend on the router you have whether the access is in one place or another, but basically you have to look for the option to change the broadcast channel. In our router, which is a ZTE F680, the option is in “Network” > “WLAN Radio 2.4G”. By default it is usually set to automatic, a recommended option because in theory it chooses the one that best suits our location, but if you still want to modify it, select the corresponding section and modify it.
Save the changes and voila, changed channel. In theory you should notice a small cut and then an improvement in the connection. This may be temporary, because if your neighbors routers are set to automatic and they detect that the channel you are using is the best, they will change and you will have to repeat the process. At least you know how.
Picture | Wikimedia Commons