WiFi - Is it a good idea to use channels 3 or 7 in the 2.4GHz band? by Ulises Cázares

This is a common question that a lot of non-wifi persons ask me because a more than a few of "house" routers/modems set themselves to channels like 3 or 7 and these persons think is "better" since they are in different channels than the the rest of routers/modems in the surrondings.

The short answer is Nooooo, please don't do that.

The long answer is that is Not a good idea since if a router is set to channel 3 it will use spectrum that is use by channel 1 as well as channel 6, and if one device is set to channel 7 it will use the spectrum of channel 6 as well as spectrum of channel 11 and this could cause retransmissions in those channels instead of causing retransmissions in only one channel.

The best thing we can do is to set the device in one of the 3 channels (1, 6 or 11) that has the less router/modems set to the same of ours. 

 With the following image you can see, when the lines of a channel intersec with another, that channel 3 will interefere (adjacent-channel) with channels 1,2,4,5,6,and even 7. For the channel 7 case it will interfere with channels 3, 4, 5, 6, 8, 9,10 and 11


 

But remember, the 2.4GHz is pretty saturated and retransmissions will occur no matter what, but lets try to mitigate the efect as much as we can.



Comments

  1. FerCFebruary 16, 2022 at 9:10 AM

    For more technical detail..

    https://www.metageek.com/training/resources/why-channels-1-6-11/

    Thanks for the post!

    ReplyDelete
  2. EsaúFebruary 16, 2022 at 9:54 AM

    thanks Ulises, good post.

    It would be interesting a post about why if they use channel 3 it will use the spectrum of channel 1.

    ReplyDelete

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