Dr. Samir Al Ghadban.

klapdorothypondMobile - Wireless

Nov 23, 2013 (3 years and 11 months ago)

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Dr. Samir Al Ghadban.

EE 205


Term 121

Wireless and mobile data
networks (
WiFi
,
WiMax
)


What is wireless communication ?




Examples of wireless networks:


1 Wifi


2 WiMax


Introduction


What is the
wifi
?



W
ireless
f
idelity (
wifi
).



History : it is invented in 1991 by NCR
corporation. it is used for cashier system. Its
name was
WaveLan

with speed 1
-
2Mbps.



Wifi



Who invented
wifi
?


The father of
wifi

is
Vic Hayes
.



Wifi refers to a type of Ethernet specified
under the IEEE 802.11a and 802.11b
standards for LANs operating in the 5


2.4
GHz unlicensed frequency bands respectively.



WiFi

uses radio waves

to
transmit

the
information to and from the internet or your
computer network. When a website wants to
communicate with your computer it sends the
information to your
modem

as it does now on
your wired connection, then the information
is passed on to a wireless router, which then
converts it to radio waves and beams it to
your computer.

How
does it work
?


Hotspots are areas where WiFi radio signals
can be picked up by your computer. At home,
a wireless router (such as the one shown at
right) does the job to make your entire home
a hotspot.

What
are
WiFi

Hotspots?


WiMAX



What
is the
wimax

?


Worldwide interoperability for microwave
access (
WiMAX
).



Definition.

wimax


Goal of wimax


Provide high speed internet access to home
and business subscriber.




Infrastructure:


1 access point


2 base station (BS)


3 subscribers stations( SS)




How does it work ?


Tower (BS): similar to a cell phone tower. Can
provide to coverage to a very large area( 8000
km).


A wimax receiver: the receiver and antenna
could be small box or PCMCIA card or could
be built in a laptop.


During communication all information
come from SS to the BS and retransmit
to the right SS.



Range and data rate :


Wi
-
Fi : around 30 meters.


WiMAX : In theory 112 Km.



expected value : 2 Km. ( under conditions).



Wi
-
Fi : around 54 Mbit.


WiMAX : In theory 70 Mbit.


expected value : 10 Mbit.


Comparing


Physical layer :


Wi
-
Fi : operates at 2.4
-
5GHz.


Wi
-
MAX : operates at 10


66GHz.



Users:


Wi
-
Fi: 1
-
10s for each CPE.


Wi
-
MAX: 1
-
100s for each CPEs.





Cost:


Wifi is cheap.


Wimax is costly.



Quality of service:


http://www.youtube.com/watch?v=Upl1IJbvM
Ok


Video


http://mail.baskent.edu.tr/~20394676/0401
/bil431/hw/burak
-
usgurlu
-
lastHW
-
wifiVSwimax.pdf
.


http://www.tutorialspoint.com/wimax/wirele
ss_introduction.htm


http://www.squidoo.com/what
-
is
-
wifi


http://en.wikipedia.org/wiki/Wi
-
Fi



Refrences



Ahmed Al Ghamdi.


200967650

Haider Al Ahmed.


200967810

Yousef Al Shahrani.


200956090