Wireless IEEE 802.11 N

8/2/2019 Wireless IEEE 802.11 N

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[WIRELESS N 802.11 N ALI GHALEHBAN ASSUMPTION UNIVERSITY ]

1 Assumption University Of Thailand Ali Ghalehban

Wireless N 802.11N

Assumption University of Thailand

ICT 6201- Mobile and Wireless Network (3/2011) Term paper

Ali Ghalehban Zanajab

[email protected]

Introduction

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

have very higher speed from 54 Mbit/s to 600 Mbit/s this standard improve

network throughput over the two previous standards 802.11a and 802.11g .802.11n

standardized support for multiple-input multiple-output and frame aggregation, and

security improvements, among other features. With speeds of up to 600 Mbps, the

emerging 802.11n standard is the next generation of wireless networking,

delivering the speed, range, and reliability to support the most bandwidth intensive

applications. 802.11n incorporates 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 generate the high speeds and at the same time

communicate with 802.11b/g devices. 802.11n specification was approved in

September 2009. Manufactureres are committed to collaborating with the IEEE

and WiFi Alliance to ensure that 802.11n devices will interoperate at the highest

speeds without degrading performance of neighboring 802.11b/g wireless

networks.
mailto:[email protected]:[email protected]


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802.11 N vs 802.11a/b/gHere in blowe we will have a brief compartion between other wireless standards

and Wireless N standard . if you check 2 last column you can see that Wireless N

Outdoor & indoor range (70 m250 m ) is higher than other Standards .

802.11 network standards Table

802.11

protocol

Freq.

(GHz)

Bandwi

dth

(MHz)

Data rate per stream

(Mbit/s)

Modulatio

n

Approximate

indoor range

Approximate outdoor

range

(m) (ft) (m) (ft)

Legacy

mode

2.4 20 1, 2DSSS,FH

SS20 66 100 330

a

5

206, 9, 12, 18, 24, 36, 48,

54OFDM

35 115 120 390

3.7 5,000 16,000

b 2.4 20 1, 2, 5.5, 11 DSSS 35 115 140 460

g 2.4 206, 9, 12, 18, 24, 36, 48,

54

OFDM,DS

SS38 125 140 460

n 2.4/5

207.2, 14.4, 21.7, 28.9,

43.3, 57.8, 65, 72.2

OFDM

70 230 250 820

40 15, 30, 45, 60, 90, 120,135, 150

70 230 250 820
http://en.wikipedia.org/wiki/IEEE_802.11_(legacy_mode)http://en.wikipedia.org/wiki/IEEE_802.11_(legacy_mode)http://en.wikipedia.org/wiki/IEEE_802.11_(legacy_mode)


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802.11 N More Antenna = Higher Speed

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) tomake High speed an also in other hand for communicate with devices that use

802.11b and g standards . This standard with using of above ways is able to

supports much faster wireless connections over longer distances.also support of

multiple radios and antennas that can transmit/receive multiple data streams . send

and receive Antenna configuration in 802.11 N must be in 11, 12, 22, or 33

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

802.11 N device pay attention to below table .as you see in table in every device

speed is different and its related to Antenna More Antenna = Higher Speed but I

must mention In general multiple antennas do not by themselves increase data

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-user MIMO, a multi-antenna transmitter communicates simultaneously

with multiple receivers This is known as space-division multiple access (SDMA)

and because 802.11 use MIMO for transmit and receive data and because MIMO

use multilayer for working 802.11 use precoding techniques for this actions .

Precoding is 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

streams using one 40 MHz-wide channel. Various modulation schemes and coding

rates are defined by the standard and are represented by a Modulation and Coding

Scheme (MCS) index value. The table below shows the relationships between the

variables that allow for the maximum data rate

20/40 MHz Channels

APs and stations must exchange information about the channels they will use to

communicate. In 802.11n, this is done by sending HT Information and Capabilities

Elements to indicate channel width (20 or 40 MHz), primary channel number, and 40

MHz secondary channel offset. To promote peaceful coexistence, an 802.11n AP can

automatically move to another channel or switch to 20 MHz operation if another AP

starts operating in either half of the designated 40 MHz channel


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802.11 N Operation modes

There are three 802.11n operating modes:

HT : AP using High Throughput (HT) mode also known as Greenfield mode .

Non-HT: AP using Non-HT mode sends all frames in the old 802.11a/g format so

that legacy stations can understand them

HT Mixed : HT enhancements can be used simultaneously with HT Protection

mechanisms that permit communication with legacy stations.


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Migration to 802.11 N & 802.11 N in Market

Maybe 802.11 N isnt enough famous between people in social but if everybody

be familiar with this standard speed doubtless will move from older standards to

this new one Now days you can to find 802.11 N supported devices in market is

easy and with compare with other standard price is not so high . Here in below I

will introduce some company with its 802.11 N supported Device.

Belkin Company wireless broadband router (F5D8320-4) Linksys WRT300N Wireless-N Broadband Router TRENDnet TEW-631BRP NETGEAR WNR834B RangeMax NEXT Wireless-N Router

References:

http://en.wikipedia.org/wiki/IEEE_802.11n-2009#Data_encoding

http://www.arubanetworks.com/technology/upgrade-to-802-11n/

http://en.wikipedia.org/wiki/IEEE_802.11

http://www.computerworld.com/s/article/9019472/FAQ_802.11n_wireless_networking

http://www.everymac.com/systems/apple/apple-tv/apple-tv-faq/what-is-802.11n-differences-between-802.11n-802.11a-

802.11b-802.11g.html
http://en.wikipedia.org/wiki/IEEE_802.11n-2009#Data_encodinghttp://en.wikipedia.org/wiki/IEEE_802.11n-2009#Data_encodinghttp://www.arubanetworks.com/technology/upgrade-to-802-11n/http://www.arubanetworks.com/technology/upgrade-to-802-11n/http://en.wikipedia.org/wiki/IEEE_802.11http://en.wikipedia.org/wiki/IEEE_802.11http://www.computerworld.com/s/article/9019472/FAQ_802.11n_wireless_networkinghttp://www.computerworld.com/s/article/9019472/FAQ_802.11n_wireless_networkinghttp://www.everymac.com/systems/apple/apple-tv/apple-tv-faq/what-is-802.11n-differences-between-802.11n-802.11a-802.11b-802.11g.htmlhttp://www.everymac.com/systems/apple/apple-tv/apple-tv-faq/what-is-802.11n-differences-between-802.11n-802.11a-802.11b-802.11g.htmlhttp://www.everymac.com/systems/apple/apple-tv/apple-tv-faq/what-is-802.11n-differences-between-802.11n-802.11a-802.11b-802.11g.htmlhttp://www.everymac.com/systems/apple/apple-tv/apple-tv-faq/what-is-802.11n-differences-between-802.11n-802.11a-802.11b-802.11g.htmlhttp://www.everymac.com/systems/apple/apple-tv/apple-tv-faq/what-is-802.11n-differences-between-802.11n-802.11a-802.11b-802.11g.htmlhttp://www.computerworld.com/s/article/9019472/FAQ_802.11n_wireless_networkinghttp://en.wikipedia.org/wiki/IEEE_802.11http://www.arubanetworks.com/technology/upgrade-to-802-11n/http://en.wikipedia.org/wiki/IEEE_802.11n-2009#Data_encoding

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Wireless IEEE 802.11 N