Wireless LAN - 802.11 frequency bands | WiFi Channels Explained

In this video, we are going to discuss about frequency channel assigned to Wireless LAN.
We know that frequency is defined as the number of cycles per second, and we communicate using frequencies and I have discussed various frequency ranges and their applications in one of my other videos.
WLAN operates in two bands, namely 2.4 GHz and 5GHz. These bands also know as ISM band, ISM stands for Industrial- Scientific and Medical. In addition to WLAN these bands are also used in other wireless technologies like cordless phones, Bluetooth devices, near field communication (NFC) devices
So…. What is band? So the band is a range of frequencies - It mean 2.4 band is basically a range for frequencies which start from 2.400 to 2.4835.
This range is further divided into sub-bands, called channels and these channel are allocated to for communications between a WiFi devices like a laptop and the AP.
The first channel starts at 2.401 and ends at 2.423. this makes 22 MHz which means each WiFi signal occupies 22 MHz. The middle of this channel range is called the center frequency and channel is known by its center frequency as well as channel number, like this channel has got number 1.
The second channel starts after a gap of 5MHz, it means the second channel will start from 2.406 and ends at 2.428 and the center frequency will be 2.417 and the channel number would be 2. In the same way, third channel is defined by keeping a 5MHz gap from the previous one and we keep defining the channels. One important point to note is that these channel are overlapping with each other, it means communication taking place in these nearby or adjacent channel will interfere with each other.
But we will reach a channel, like channel 6, where there is no overlap between channel number 1 and channel number 6. It means if in the same BSS, if we use channel number 1 and 6 then there will not any overlap and communication will not be disturbed.
#wirelessbands
#ISMband
#WiFi

[@James_Knott]

One thing to bear in mind is the channel numbers were set with the original 802.11 from 1997 and were all non overlapping. With 802.11b, each channel now takes 5 of the original channels. This is why only channels 1, 6 & 11 are used.

[@GDNetworkingNewbie]

Thank you for your comment with more information.

[@CyberDrone0]

great video with easy explanation. I have an interview in an hour and this info is crucial. thank you

[@GDNetworkingNewbie]

Glad it was helpful!

[@SandyWhistle]

its kinda difficult topic but its actually good video pretty easy to understand, thanks

[@GDNetworkingNewbie]

Glad it helped!

[@jesseboit5224]

Great explanation, thank you very much.

[@GDNetworkingNewbie]

Glad it was helpful!

[@firemelon8725]

this explanation is better than Professor Messer

[@GDNetworkingNewbie]

so nice of you, bro

[@desmondkang8651]

In electromagnetic physics, waves with shorter wavelength and higher frequency (eg. Gamma Rays) tends to have higher penetrating power than waves with longer wavelength and lower frequency (eg. Radiowaves). In between 2.4GHz band and 5GHz band (13:38), why is 2.4GHz (lower frequency) being more penetrative than 5GHz(higher frequency)? Given that both 2.4GHz and 5GHz are Radiowaves.

[@GDNetworkingNewbie]

One reason why 2.4GHz waves may be more penetrative than 5GHz waves is that 2.4GHz waves are less affected by obstacles in their path. This is because they have longer wavelengths and are better able to diffract around objects. 5GHz waves, on the other hand, have shorter wavelengths and are more likely to be absorbed or reflected by obstacles, which can limit their penetrating power.

[@tokoiaoben3842]

Since channel 1,6 and 11 are not overlapping with each other and If I have 2 APs (operate in 2.4 band) both set to channel 11 is there going be interfering with each other ? OR I should set one AP to channel 1 (or channel 3) the other AP should be set channel 11 ?

[@GDNetworkingNewbie]

If two access points using same channel are nearby then this may create interference, as per my understanding, it is recommended to use channel 1(2) and 11

[@francocastilloAR]

Why is 20 MHz used in 2.4 GHz and not lower bandwidths?

[@GDNetworkingNewbie]

may be, because there are several overlapping channels in this band

[@aletubecordoba]

in my experience, channels 1 and 2 are the best

[@GDNetworkingNewbie]

Thank you very much for sharing your experience

[@abdulfattahalhousein9634]

Exe.

[@GDNetworkingNewbie]

Thanks!