wifi - What is a wireless channel? -



wifi - What is a wireless channel? -

as question , don't understand wireless channel.

supposed have access point standard 802.11b, utilize frequency 2.4 ghz -->is bandwith? , transfer rate of standard 11 mbps. relationship between them? , why have split bandwith different channels?

thanks in advanced.

2.4ghz frequency @ wireless channel exists. in reality 802.11b uses radio frequency spectrum between 2400mhz 2450mhz divided 11 channels (sometimes 13 or 14 channels, depending on regional regulatory laws). separation channels done allow multiple wireless channels coexist.

the image below wikipedia illustrates separation channels pretty nicely:

the bandwidth of each channel 22 mhz 802.11b specifically, other variants of 802.11 allows various other bandwidths. defined in 802.11b specification.

the maximum data-rate of 802.11b 11 mbit/s. 802.11 supports info rate adaptation, means communication scheme adapt current signal-to-noise ratio (snr). lower info rates more robust against noise. data-rate related bandwidth of channel, depends on modulation used.

this not mean can transfer 11mbit/s of info on 802.11b channel, have take overhead business relationship @ various protocol layers.

i hope clears confusion you. read wikipedia page on ieee 802.11. :)

wifi wireless channel 802.11

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