Wireless IEEE 802.11 N

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Wireless N 802.11N

Assumption University of Thailand Assumption University of Thailand ICT 6201- Mobile and

ICT 6201- Mobile and Wireless Network (3/2011) Term paperWireless Network (3/2011) Term paper Ali Ghalehban Zanajab

Ali Ghalehban Zanajab [email protected] [email protected]

Introduction

IEEE 802.11n is wireless Network standard that In compare with prior standards IEEE 802.11n is wireless Network standard that In compare with prior standards have very

have very higher speed higher speed from from 54 Mbit/s 54 Mbit/s to 600 to 600 Mbit/s Mbit/s this standarthis standard improved improve network throughput over the two previous standards 802.11a

network throughput over the two previous standards 802.11a and 802.11g .802.11nand 802.11g .802.11n standardized support for multiple-input multiple-output and frame aggregation, and standardized support for multiple-input multiple-output and frame aggregation, and security improvements, among other

security improvements, among other features.features. With speeds of up to 600 Mbps, theWith speeds of up to 600 Mbps, the emerging 802.11n standard is the next generation of wireless networking, emerging 802.11n standard is the next generation of wireless networking, delivering the speed,

delivering the speed, range, and reliabilirange, and reliability ty to support the mto support the most bandwidth intensiveost bandwidth intensive applications.

applications. 802.11n 802.11n incorporates incorporates multiple multiple technologies technologies including including SpatialSpatial Multiplexing MIMO (Multi-In, Multi- Out), 20 and 40 MHz channels, and dual Multiplexing MIMO (Multi-In, Multi- Out), 20 and 40 MHz channels, and dual bands (2.4 GHz

bands (2.4 GHz and 5 GHz) and 5 GHz) to generate to generate the high speedthe high speeds and at the s and at the same timesame time communicate

communicate with 802.with 802.11b/g 11b/g devices. devices. 802.11n 802.11n specification specification was apprwas approved ioved inn September

September 2009. 2009. Manufactureres Manufactureres are are committed committed to to collaborating collaborating with with the the IEEEIEEE and WiFi

and WiFi Alliance to ensurAlliance to ensure that 802.11e that 802.11n devices will inn devices will interoperate at the teroperate at the highesthighest speeds

speeds without without degrading degrading performance performance of of neighboring neighboring 802.11b/g 802.11b/g wirelesswireless networks.

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802.11 N vs

802.11 N vs 802.11a/b/g

802.11a/b/g

Here in blowe we

Here in blowe we will have a brief compartion between other wireless standardswill have a brief compartion between other wireless standards and Wireless N stand

and Wireless N standard ard . if you check 2 . if you check 2 last column ylast column you can see that Wireou can see that Wireless Nless N Outdoor &

Outdoor & indoor indoor range range (70 m(70 m – – 250 m ) is higher than other Standards .250 m ) is higher than other Standards .

802.11 network standards Table

802.11 802.11 protocol protocol Freq. Freq. (GHz) (GHz) Bandwi Bandwi dth dth (MHz) (MHz)

Data rate per stream Data rate per stream

(Mbit/s) (Mbit/s) Modulatio Modulatio n n Approximate Approximate indoor range indoor range Approximate outdoor Approximate outdoor range range (m) (m) (ft) (ft) (m) (m) (ft)(ft) — — Legacy Legacy mode mode 2.4 2.4 20 20 1, 1, 22 DSSS,FHDSSS,FH SS SS 20 20 66 66 100 100 330330 aa 5 5 20 20 6, 9, 12, 18, 24, 36, 48,6, 9, 12, 18, 24, 36, 48, 54 54 OFDMOFDM 35 35 115 115 120 120 390390 3.7 3.7 — — — — 5,000 5,000 16,00016,000 b b 2.4 2.4 20 20 1, 1, 2, 2, 5.5, 5.5, 11 11 DSSS DSSS 35 35 115 115 140 140 460460 g g 2.4 2.4 2020 6, 9, 12, 18, 24, 36, 48,6, 9, 12, 18, 24, 36, 48, 54 54 OFDM,DS OFDM,DS SS SS 38 38 125 125 140 140 460460 n 2.4/5 n 2.4/5 20 20 7.2, 14.4, 21.7, 28.9,7.2, 14.4, 21.7, 28.9, 43.3, 57.8, 65, 72.2 43.3, 57.8, 65, 72.2 OFDM OFDM 70 70 230 230 250 250 820820 40 40 15, 30, 45, 60, 90, 120,15, 30, 45, 60, 90, 120, 135, 150 135, 150 70 70 230 230 250 250 820820

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802.11 N More Antenna = Higher Speed

802.11 N uses multiple technologies including Spatial Multiplexing MIMO 802.11 N uses multiple technologies including Spatial Multiplexing MIMO (Multi-In, Multi-Out), 20 and 40 MHz channels, and dual bands (2.4 GHz and 5 GHz) to In, Multi-Out), 20 and 40 MHz channels, and dual bands (2.4 GHz and 5 GHz) to make High speed an also in other hand for communicate with devices that use make High speed an also in other hand for communicate with devices that use 802.11b and

802.11b and g standards . g standards . This standard This standard with using with using of of above ways above ways is able tis able too supports much faster wireless connections over longer distances.also support of supports much faster wireless connections over longer distances.also support of multiple radios and antennas that can transmit/receive multiple data streams . send multiple radios and antennas that can transmit/receive multiple data streams . send and receive Ante

and receive Antenna configuranna configuration in 802.11 N mtion in 802.11 N must be in ust be in 1×1, 1×2, 2×2, or 1×1, 1×2, 2×2, or 3×33×3 status these numbers show us how many transmit and receive antennas and radios status these numbers show us how many transmit and receive antennas and radios are in an 802.11n access point (AP) or client. And also when you want to buy a are in an 802.11n access point (AP) or client. And also when you want to buy a 802.11 N device pay attention to below table .as you see in table in every device 802.11 N device pay attention to below table .as you see in table in every device speed is differ

speed is different and it’s rent and it’s related to Antenna elated to Antenna More Antenna = More Antenna = Higher SpeedHigher Speed but Ibut I must

must mention mention In In general general multiple multiple antennas antennas do do not not by by themselves themselves increase increase datadata rate or range infact Those improvements come from how the MIMO device rate or range infact Those improvements come from how the MIMO device actually uses its multiple antennas .

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Data Encoding & Rate in 802.11 N

In

multi-In multi-user MIMO, user MIMO, a multi-antenna multi-antenna transma transmitter committer communicates unicates simultaneouslysimultaneously with multiple receivers This is known as space-division multiple access (SDMA) with multiple receivers This is known as space-division multiple access (SDMA) and because 802.

and because 802.11 use MIMO f11 use MIMO for or transmit transmit and receive datand receive data and because MIa and because MIMOMO use multilaye

use multilayer for worr for working 802.11 king 802.11 use precodinuse precoding techniques g techniques for this acfor this actions tions ..

Precoding

Precoding is a generalization of beamforming to support multi-layer transmissionis a generalization of beamforming to support multi-layer transmission in multi-antenna wireless communications .

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802.11 N Data rate Table

Data rates up to 600 Mbit/s are achieved only with the maximum of four spatial Data rates up to 600 Mbit/s are achieved only with the maximum of four spatial streams using one 40

streams using one 40 MHz-wide channel. Various modulation schemes and codingMHz-wide channel. Various modulation schemes and coding rates are defined by the

rates are defined by the standard and are represented by a standard and are represented by a Modulation and CodingModulation and Coding Scheme (MCS) index value. The

Scheme (MCS) index value. The table below shows the table below shows the relationships between therelationships between the variables that allow for the

variables that allow for the maximum data ratemaximum data rate

20/40 MHz Channels

APs and stati

APs and stations must exchaons must exchange informnge information about tation about the channels he channels they will they will use touse to communicate.

communicate. In 802.11n, thIn 802.11n, this is done by is is done by sending HT Information sending HT Information and Capabilitiesand Capabilities Elements to indicate channel width (20 or 40 MHz), primary channel number, and 40 Elements to indicate channel width (20 or 40 MHz), primary channel number, and 40 MHz secondary chan

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802.11 N Operation modes

There are three 802.11n operating modes: There are three 802.11n operating modes: HT

HT :: AP using HigAP using High Throughput h Throughput (HT) m(HT) mode ode also known aalso known as Greenfield s Greenfield mode .mode . Non-HT:

Non-HT: AP using Non-HT mode sends all frames in the old 802.11a/g format soAP using Non-HT mode sends all frames in the old 802.11a/g format so that legacy stations can

that legacy stations can understand themunderstand them HT Mixed :

HT Mixed : HT enhancements can be used simultaneously with HT ProtectionHT enhancements can be used simultaneously with HT Protection mechanisms that permit communication with legacy

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Migration to 802.11 N & 802.11 N in Market

Maybe 802.11 N

Maybe 802.11 N isn’t enough famisn’t enough famous between people in ous between people in social but if eversocial but if everybodyybody be familiar with this standard speed doubtless will move from older standards to be familiar with this standard speed doubtless will move from older standards to this new one N

this new one Now days you caow days you can n to find 802.to find 802.11 N supported 11 N supported devices in mardevices in market isket is easy and with compare with other standard price is not so high . Here in below I easy and with compare with other standard price is not so high . Here in below I will introduce some company with its

will introduce some company with its 802.11 N supported Device.802.11 N supported Device.

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 Belkin Company wireless broadband router (F5D8320-4)Belkin Company wireless broadband router (F5D8320-4) 

 Linksys WRT300N Wireless-N Broadband RouterLinksys WRT300N Wireless-N Broadband Router

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 TRENDnet TEW-631BRPTRENDnet TEW-631BRP

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 NETGEAR WNR834B RangeMax NEXT Wireless-N RouterNETGEAR WNR834B RangeMax NEXT Wireless-N Router

References: References: http://en.wikipedia.org/wiki/IEEE_802.11n-2009#Data_encoding http://en.wikipedia.org/wiki/IEEE_802.11n-2009#Data_encoding http://www.arubanetworks.com/technology/upgrade-to-802-11n/ http://www.arubanetworks.com/technology/upgrade-to-802-11n/ http://en.wikipedia.org/wiki/IEEE_802.11 http://en.wikipedia.org/wiki/IEEE_802.11