802.11 Protocol Stack and Physical Layer

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    Rafn` dg Cdit`its

    1. Afstractmdi

    6. Mitrdbuctmdi

    6.1 Dv`rvm`w

    6.6 [mr`n`ss Ndcan Ar`a I`twdre

    6.3 Rj` Fasmc Structur` dg a [mr`n`ss NAI

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    Afstractmdi

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    A!# as cd!cnusmd! w` wmnn sa= tjat wmr`n`ss !`twdrem!" jas a rdomsm!" gutur` wmtj

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    Rj` *asmc Structur` dg a (mr`n`ss A)

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    [NAIs t=mcann= us` tj` u!nmc`!s`# %!#ustrman9 Scm`!tmgmc9 a!# 7`#mcan (%S7) ra#mdgr`5u`!c= a!#s. %! tj` !mt`# Stat`s9 tj` %S7 a!#s m!cnu#` tj` >+7; a!# (>6B>6u`icy =d,,mi- S,r`ab S,`ctru+ /5=SS

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    Rj` 8;SS tra!somtt`r ms a s`u#d+!dms` 'I cd#` cd!trdnn`# gr`5u`!c= s=!tj`sm`r. Rj`m!sta!ta!`dus gr`5u`!c= dutut dg tj` tra!somtt`r ?uos grdo d!` vanu` td a!dtj`r as`# d! tj`s`u#d+ra!#do m!ut grdo tj` cd#` "`!`ratdr. 4ar=m!" tj` m!sta!ta!`dus gr`5u`!c= r`sunts m! a!dutut s`ctruo tjat ms `gg`ctmv`n= sr`a# dv`r tj` ra!"` dg gr`5u`!cm`s "`!`rat`#.

    8m".1 8;SS S`ctruo

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    mr`ct S`>u`ic` S,r`ab S,`ctru+ /SSS

    /mr`ct S`5u`!c` Sr`a# S`ctruo ms as`# d! tj` ountmn=m!" dg tj` as`a!# sm"!an #ata wmtj arda#a!# sr`a#m!" cd#`. Rj` r`sunt ms t`ro`# tj` cjm rat`. Rj` cjaract`rmstmcs dg tj`rda#a!# sr`a#m!" cd#` ar` tjat dg s`u#dra!#do !dms`. Cd!s`5u`!tn= tj` r`c`mv`rs=!cjrd!m`# td tj` cd#` wmnn dtam! tj` !arrdwa!# sm"!an. Ann dtj`r r`c`mv`rs wmnn s`` tj`sr`a# sm"!an as wjmt` dr cdndr`# !dms`.%! cd!trast9 gr`5u`!c=+jdm!" sr`a# s`ctruos`u#d+ra!#don= r`tu!`s tj` carrm`r9 m!st`a# dga##m!" s`u#d+ra!#do !dms` td tj` #ata9 wjmcj r`sunts m! a u!mgdro gr`5u`!c= #mstrmutmd! wjds`wm#tj ms #`t`rom!`# = tj` dutut ra!"` dg tj`s`u#d+ra!#do!uo`r "`!`ratdr.%! t`n`cdoou!mcatmd!s9 #mr`ct+s`5u`!c` sr`a# s`ctruo ms aod#unatmd! t`cj!m5u` wj`r` tj`tra!somtt`# sm"!an tae`s u odr`a!#wm#tjtja! tj` m!gdroatmd! sm"!an tjat ms `m!" od#unat`#9

    wjmcj ms tj` r`asd! tjat mt ms cann`#sr`a# s`ctruo. /SSS jas tj` gdnndwm!" g`atur`s*gdr "`!`ratm!" sr`a#+s`ctruo tra!somssmd!s =jas`+od#unatm!" asm!` wav`s`u#d ra!#don=wmtj a cd!tm!udus strm!"dgs`u#d !dms`cd#`s=odns9 `acj dg #uratmd! oucj soann`r tja! amt.A sm"!an structurm!" t`cj!m5u` utmnmm!" a #m"mtancd#`s`5u`!c`('I S`5u`!c`s) javm!" acjmrat`oucj jm"j`r tja! tj` m!gdroatmd! sm"!anmt rat`. &acj m!gdroatmd! mt dg a #m"mtan sm"!anmstra!somtt`# as a s`u#dra!#do s`5u`!c` dg cjms.

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    http://en.wikipedia.org/wiki/Frequency-hopping_spread_spectrumhttp://en.wikipedia.org/wiki/Pseudo-random_numberhttp://en.wikipedia.org/wiki/Telecommunicationhttp://en.wikipedia.org/wiki/Modulationhttp://en.wikipedia.org/wiki/Bandwidthhttp://en.wikipedia.org/wiki/Spread_spectrumhttp://en.wikipedia.org/wiki/Phase_modulationhttp://en.wikipedia.org/wiki/Sine_wavehttp://en.wikipedia.org/wiki/Pseudorandomhttp://en.wikipedia.org/wiki/String_(computer_science)http://en.wikipedia.org/wiki/Pseudonoisehttp://en.wikipedia.org/wiki/Codehttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Signaling_(telecommunication)http://en.wikipedia.org/wiki/Digitalhttp://en.wikipedia.org/wiki/Sequencehttp://en.wikipedia.org/wiki/PN_Sequenceshttp://en.wikipedia.org/wiki/Chip_ratehttp://en.wikipedia.org/wiki/Chip_ratehttp://en.wikipedia.org/wiki/Informationhttp://en.wikipedia.org/wiki/Bit_ratehttp://en.wikipedia.org/wiki/Digital_signalhttp://en.wikipedia.org/wiki/Frequency-hopping_spread_spectrumhttp://en.wikipedia.org/wiki/Pseudo-random_numberhttp://en.wikipedia.org/wiki/Telecommunicationhttp://en.wikipedia.org/wiki/Modulationhttp://en.wikipedia.org/wiki/Bandwidthhttp://en.wikipedia.org/wiki/Spread_spectrumhttp://en.wikipedia.org/wiki/Phase_modulationhttp://en.wikipedia.org/wiki/Sine_wavehttp://en.wikipedia.org/wiki/Pseudorandomhttp://en.wikipedia.org/wiki/String_(computer_science)http://en.wikipedia.org/wiki/Pseudonoisehttp://en.wikipedia.org/wiki/Codehttp://en.wikipedia.org/wiki/Bithttp://en.wikipedia.org/wiki/Signaling_(telecommunication)http://en.wikipedia.org/wiki/Digitalhttp://en.wikipedia.org/wiki/Sequencehttp://en.wikipedia.org/wiki/PN_Sequenceshttp://en.wikipedia.org/wiki/Chip_ratehttp://en.wikipedia.org/wiki/Chip_ratehttp://en.wikipedia.org/wiki/Informationhttp://en.wikipedia.org/wiki/Bit_ratehttp://en.wikipedia.org/wiki/Digital_signal
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    Rj` rm!cmn` dgmr`ct S`qu`ic`ms td sr`a# a sm"!an d! a nar"`r gr`5u`!c= a!# = ountmn`-m!"mt wmtj a sm"!atur` dr cd#` td om!mom` ndcanm`# m!t`rg`r`!c` a!# ace"rdu!# !dms`. Rd sr`a#tj` sm"!an9 `acj mt ms od#unat`# = a cd#`. %! tj` r`c`mv`r9 tj` drm"m!an sm"!an ms r`cdv`r`# =r`c`mvm!" tj` wjdn` sr`a# cja!!`n a!# #`od#unatm!" wmtj tj` sao` cd#` us`# = tj`tra!somtt`r. Rj`

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    8m". 1 F'S /SSS S`ctruoRj` a!#wm#tj m! /SSS s=st`os ms dgt`! tae`! as tj` !unn+td+!unn a!#wm#tj dg tj` oam! nd` dgtj` dw`r s`ctran #`!smt= ndt (m!#mcat`# as 6:c m! 8m". 1). Rj` jang dw`r a!#wm#tj dg tjmsnd` ms 1.6 :c9 wj`r` :c ms tj` cjm rat`. Rj`r`gdr`9 tj` a!#wm#tj dg a /SSS s=st`o ms a #mr ctgu!ctmd! dg tj` cjm rat`K s`cmgmcann= 6:c0:%I8D. Rjms ms ?ust a! `-t`!smd! dg tj` r`vmdus`5uatmd! gdr rdc`ss "am!. %t sjdun# ` !dt`# tjat tj` dw`r cd!tam!`# m! tj` oam! nd`cdorms`s > `rc`!t dg tj` tdtan dw`r. Rjms anndws a !arrdw`r :8 a!#wm#tj td accdood#at`tj` r`c`mv`# sm"!an wmtj tj` `gg`ct dg rdu!#m!" tj` r`c`mv`# uns`s m! tj` tmo` #doam!.D!` g`atur` dg /SSS ms tjat 'S oa= ` us`# td m!cr`as` tj` #ata rat`. Rjms m!cr`as` dg agactdr dg twd mts `r s=odn dg tra!somtt`# m!gdroatmd! dv`r F'S caus`s a! `5umvan`!tr`#uctmd! m! tj` avamnan` rdc`ss "am!. Rj` rdc`ss "am! ms r #uc`# `caus` gdr a "mv`! cjmrat`9 tj` a!#wm#tj (wjmcj s`ts tj` rdc`ss "am!) ms janv`# #u` td tj` twd+gdn# m!cr`as` m!m!gdroatmd! tra!sg`r. Rj` r`sunt ms tjat s=st`os m! a s`ctrann= 5um`t `!vmrd!o`!t `!`gmt grdo tj`dssmn` m!cr`as` m! #ata tra!sg`r rat`.

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    twd #ata mts. Rjms ms a cn`v`r rdc`ss tjat `!an`s tj` #ata str`ao td ` s`!t at 67s wjmn`usm!" tj` sao` aodu!t dg a!#wm#tj as tj` d!` s`!t at 17s. Rj` od#unatdr us`s smomnaro`tjd#s gdr tj` jm"j`r9 $.$7s a!# 117s #ata rat`s.

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    Rrais+mt 5r`>u`icm`s

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    A odr` o`a!m!"gun o`tjd# gdr vm`wm!" D8/7 sm"!an dw`r cjaract`rmstmcs us`s tj`cdon`o`!tar= cuounatmv` #mstrmutmd! gu!ctmd! (CC/8). Rjms o`trmc nm!es a `rc`!ta"`rdamnmt= td a dw`r n`v`n. %! tjms o`asur`o`!t9 a! m!struo`!t wmtj tmo`+"atm!" caamnmt= msus`# td s`n`ct d!n= tj` actmv` drtmd! dg tj` urst (s`` 8m"ur` 6 ndw`r trac`).%g tmo` "atm!" w`r` !dt us`#9 tj` `rmd#s wj`! tj` urst ms dgg wdun# r`#uc` tj` av`ra"` dw`r

    cancunatmd!. Rj` CC/89 wjmcj ms smon= tj` odr` cdood! cuounatmv` #mstrmutmd! gu!ctmd!(C/8) sutract`# grdo 1.9 sjdws tj` !uo`r dg #`cm`ns adv` tj` av`ra"` dw`r d! tj`jdrmd!tan a-ms9 a!# `rc`!t rdamnmt= d! v`rtmcan a-ms (s`` 8m"ur` 6 u`r trac`). A CC/8o`asur`o`!t wdun# ` oa#` dv`r s`v`ran ursts td mordv` tj` accurac= dg tj` o`asur`o`!t.

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    Affr`#matmdi

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    http://searchenterprisevoice.techtarget.com/sDefinition/0,,sid66_gci213826,00.htmlhttp://searchmobilecomputing.techtarget.com/sDefinition/0,,sid40_gci1025328,00.htmlhttp://www.fcc.gov/http://searchenterprisevoice.techtarget.com/sDefinition/0,,sid66_gci213826,00.htmlhttp://searchmobilecomputing.techtarget.com/sDefinition/0,,sid40_gci1025328,00.htmlhttp://www.fcc.gov/
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