IEEE 802.11a—l999
`Fromm Ill: flee cmycqudia
`
`IEEE 802112-1999 or 802.11: was an amendment to the IEEE 802.11 wireless local network specifications that defined requirements for an orthogonal frequency division
`nnrlliplming (OFDM) comnmnication system It was originally designed to support wireless comnnmication in the unlicensed national information infiastructure (U-NlI)
`bands (in the 5—6 GHz frequency range) as regulated in the United States by the Code ofFederal Regulations, Title 47, Section 15.407.
`
`Originally describedas clause 17 ofthe 1999 specification, it is now defined in clause 18 ofthe 2012 wedfication andprovides protocols that allow transmission and
`reception ofdata at rates of 1.5 to 54Mbit/s. It has seen widespread worldwide implementation, particularly within the corporate workspace. While the original amendment
`is no longervalid, the term "802.11a" is still usedbywireless access point (cards androuters) manufacturers to describe interoperability oftheir systems at 5.8 GHz, 54
`Mbit/s (54 x 106 bits per second).
`
`802.11 is a set ofIEEE standards that govern wireless networking transmission methods. They are commonly usedtoday in their 802.lla, 802.111), 802.11g, 802.11n and
`802.11ac versions to provide wireless connectivity in the home, oflice and some commercial establishments.
`
`Contents
`
`1 Description
`2 Regulatoryissues
`3 Timing and cmnpatibility ofproducts
`4 Technical description
`5 See also
`6 References
`
`Description
`
`The802.llaamendmenttotheoriginal standardwasratifiedin1999.The802.11astandardusesthesamecoreprotocolastheoriginalstandardoperatesinSGszand,
`andusesa 52-mbcarria orthogonal
`multiplexing (OFDM) withamaximum raw data rate of54mit/s,whichyieldsrealisticnetachievablethroughpn
`inthemid—20 Mbit/s. The data rate isredueedto48, 36, 24, 18, 12, 9 then6Mbit/s ifrequired 802.11a originallyhad 12/13 non-overlapping channels, 12 that canbe used
`indoorand4/5 ofthe thhatcanbeusedinmrtdoorpointtopointconfigmations.Recentlynunycomtriesoftheworldareallowingoperationinthe5.47t05.725GHz
`Bandasasecondaryusermingasharingmethodderivedin802.11|LThiswilladdanother12/13ChamlelstotheoverallSGI-[zbandenablingsigiiflcantoverallwireless
`network capadty enabling thepossrhility of24+ channels insome countries. 802.lla isnot interoperable with 802.11b as theyoperateonseparate bands, exceptifus'ng
`upripmentthathasadualbandcapability.MostentupriseclassAccessPoinlshavedualhandcapability
`
`Usingthe 5 Gszandgives 802.11aa significant advantage, sincethe2.4Gszandisheavi1yusedtothepointofbeing a‘owded Degradationcansedbysuchconflicts
`cancausefiequentdroppedconnectionsanddegradationofservice. Hm,thislnghcarrierfi'equencyalsobrmgsashghtdisadvantage:meflxfiveovuallrmgeof
`802.11a is sligltlylessthanthatofSOZJIb/g; 802.11a signals cannotpenetrate asfarasflioseforSOZJlbbecmisetheyamabsmbedmorereadilybywaflsmdodiersolid
`objectsmflldrpathmdbecmuethepathlossmsignalsumgfliispropmfimalmthesquareofthesiylalfieqmncy.0ntheothuhmd,0FDMhasfimdamenulpropagafim
`advantageswheninahighmultipafltenvimnment, suchasanindoorofiice, andthehigherfi’equencies enablethebuilding ofsmallerantennaswithhigherRFsystemgain
`which counteractthe disadvantage ofahigherbandofoperation 'I'heincreasednumberofusablechannels (4to8timesasmanyinFCC countries)andthenearabsence of
`other interfiering systems (microwave ovens, cordless phones, baby monitors) give 802.lla significant aggegate bandwidth and reliability advantages over 802.11b/g.
`
`Regulatory issues
`
`Different countries have different regulatory support, although a 2003 World Radioteleconnmmications Conference improved worldwide standards coordination 802.11a is
`now approvedbyregulations intheUnited States andJapambut inotherareas, suchasthe EuropeanUnion, ithadto waitlongerforapproval. Europeanregnlatorswere
`considering the use ofthe European HIPERLAN standard, but in mid-2002 cleared 802.11a for use in Europe. In file U.S., a mid—2003 FCC decision may open more
`spectrumto 802.11a channels.
`
`Timing and compatibility of products
`
`802.11a products started shipping late, lagging 802.11b products due to 5 GHz components bemgmore diificultto manufacture. First generationproductperformance was
`poor andplagued with problems. When second generationproducts started shipping, 802.11a was not widely adoptedin the consumer space primarilybecause the less—
`expensive 802.11b was already widely adopted However, 802.11a later saw significant penetration into enterprise network environment, despite the
`cost
`disadvantages, particularly for businesses which required increased capacity and reliability over 802.11b/g-only networks.
`
`War the arrival ofless expensive early 802.11gproducts on themarket, whichwere backwards—compatible with 802.11b, the bandwidth advantage ofthe 5 GHz 802.lla
`was eliminated Mamrfacturus of802.11a equiprnentrespondedto the lack ofmarket success by significantly improving the implementations (current-generation 802.11a
`technologyhasrangecharacteristicsnearlyidenticaltothoseof802.llb),andbymakingtedmologythatcanusemorethanonebandastandard
`
`Dual-band, ordinal-mode Access Points andNetworkInterface Cards (NICs) that canantomatically handlea andb/g, arenow common inallthe markets, andvery close in
`price to b/g- only devices.
`
`Technical description
`
`Ofthe 52OFDMsuhcarriers,48arefordataand4arepilotsubcarrierswifliacarriaseparationof03125MHz(20MHz/64).EachofthesemlbcarrierscanbeaBPSK
`QPSK, l6—QAMor64—QAM. Thetotal bandwidthisZOMl-Izwithanoccupiedbandwidthof 16.6 MHz. Symbol durationis4microseconrk, which includesaguard
`intervalofOBmicroseconds.TheactualgenerationanddecodingoforthogonalcomponentsisdoneinbasebandusingDSPwhichisthenupconvertedto5GHzatthe
`transmitter.Eachofthe subcarrierscouldberepresentedasacornplexmnnba.ThenmedmnammglalisgeneratedbytakinganhvaseFastFomianansfmmaFFI).
`Correspondinglythereceiverdownconverts,samplesat20hfl-IzanddoesanFFTtoretrievetheoriginalcoelficients.TheadvantagesofusingOFDMincludereduced
`nnrltipath efi'ects inreception and increased spectral eflicimcy.
`.
`MICrosoft, EX. 1014
`
`Microsoft V. Bradium, IPR2016-00448
`
`Microsoft, Ex. 1014
`Microsoft v. Bradium, IPR2016-00448
`
`

`

`
`
`MCS index RATE bits Modulation Coding Data rate
`13
`1101
`16
`1111
`5
`0101
`7
`0111
`9
`1001
`11
`1011
`l
`0001
`0011
`
`
`
`
`
`
`
`
`
`See also
`
`I List of WLAN channels
`I OFDM system oompan'son table
`I Spectnl efliciency comparison table
`
`802.11 network PHY standards
`
`Stream data ntem
`
`
`1, 2, 5.5, 11
`35
`115
`
`6, 9, 12, 18, 24, 36,48, 54
`
`Nto)O
`
`MO
`
`_. _. L.2.a
`
`_. .— “Aa
`
`
`
`
`\1\1wOon
`
`400 ns GI : 7.2, 14.4, 21.7, 28.9, 43.3, 57.8, 65, 72.2 [31
`
`800 ns GI : 6.5, 13, 19.5, 26, 39, 52, 58.5, 65 [Cl
`
`400 ns GI ; 15, 30, 45, 60, 90, 120, 135, 150 [31
`800 ns GI: 13.5, 27, 40.5, 54, 81, 108, 121.5, mm
`
`400 in GI ; 7.2, 14.4, 21.7, 28.9, 43.3, 57.8, 65, 72.2, 86.7, 96.3 [31
`800 ns GI ; 6.5, 13, 19.5, 26, 39, 52, 58.5, 65, 78, 86.7 [C1
`
`400 ns GI: 15, 30,45, 60, 90, 120, 135, 150,180,200 [3]
`800m GI: 13.5, 27, 40.5, 54, 81, 108, 121.5, 135, 162, 180 [C1
`
`400 115 G1 : 32.5, 65, 97.5, 130, 195, 260, 292.5, 325, 390, 4333 [B]
`800 ns GI : 29.2, 58.5, 87.8, 117, 175.5, 234, 263.2, 292.5, 351, 390
`[C]
`
`
`
`400 ns GI ; 65, 130, 195, 260, 390, 520, 585, 650, 780, 866.7 [31
`800 ns GI : 58.5, 117, 175.5, 234, 351, 468, 702, 780 [C1
`
`Up to 6,912 (6.75 Gbit/s) [51
`
`N8
`
`Est.
`
`5 -—-III
`M
`nuearner,
`
`I Al A2 IEEE 802.11y—2008 extended opention of802.11a to the licensed 3.7 GHz band. Inueasedpower limits allow a range up to 5,000 m. As of2009, it is only bein
`licensed in the United States by the FCC.
`I 131 132 33 134 135 136 Assumes shun gum;M (551) enabled
`. Cl 02 C3 C4 CS “Assumes 51m guard M661) d‘uabled.
`
`References
`
`l "Oflicial IEEE 80211woridng group project fimelines" June 2, 2014 Retrieved 2014—06—03
`2 'Wi-Fi CERTIFIED n: Longer-Range, Faster-Throughput, Multimedia-Grade M-FiQ Netwmks"
`
`Wt-Fi Alliance Septanber 2009
`
`3 ‘80211n Delivus Benet Range" WI—Fi Planet 2007-05-31
`
`,
`.
`Microsoft EX 1014
`
`Microsoft V. Bradium, IPR2016-00448
`
`Microsoft, Ex. 1014
`Microsoft v. Bradium, IPR2016-00448
`
`

`

`4  "IEEE 802 11ac: What Does it Mean for Test?" (PDF)  LitePoint  October 2013
`5  "WiGig and IEEE 802 11ad For Multi­Gigabyte­Per­Second WPAN and WLAN" (PDF)  Tensorcom Inc
`
`General
`
`"802.11a­1999 High­speed Physical Layer in the 5 GHz band" (PDF). 1999­02­11. Retrieved 2007­09­24.
`
`Retrieved from "https://en.wikipedia.org/w/index.php?title=IEEE_802.11a­1999&oldid=740398108"
`
`Categories:  IEEE 802.11
`
`This page was last modified on 20 September 2016, at 20:37.
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`
`Microsoft, Ex. 1014
`Microsoft v. Bradium, IPR2016-00448
`
`