WIRELESS
TECHNOLOGY
ᴥ wireless technology is generally used for mobile IT equipment. It encompasses cellular
telephones, personal digital assistants (PDA's), and wireless networking.
ᴥ Other examples of wireless technology include
GPS units, garage door openers and or garage doors, wireless computer mice and
keyboards, satellite television and cordless telephones.
What is Wireless?
ᴥ Wireless networking technologies range from
global voice and data networks which allow users networks, to establish
wireless connections across long distances, to infrared light and radio
frequency technologies that are optimized for short‐range wireless connections.
Wireless network most commonly use to refer to a telecommunications
network whose interconnections between nodes is implemented without the use of wires, such as
a computer network.
Wireless telecommunications networks are
generally implemented with some type of information transmission system that
uses electromagnetic waves, such as
radio waves, for the carrier.
Wireless communication
involves
• radio
frequency communication
• microwave
communication, for example long‐range line of
sight via highly directional antennas or short line‐of‐antennas, short-range
communication.
• infrared
(IR) short‐range communication, for example from
remote controls or via IRDA Applications may involve point‐to‐point
communication, point‐to‐multipoint communication, broadcasting , cellular
networks and other wireless networks.
Devices commonly use wireless networking technologies
ᴥ portable computers,
ᴥ desktop computers,
ᴥ hand‐held computers,
ᴥ personal digital assistants (PDAs),
ᴥ cellular phones,
ᴥ pen‐based computers,
ᴥ pagers, GPS etc.
The practical purposes
ᴥ mobile users can use their cellular phone to
access e‐mail.
ᴥ Travelers with portable computers can connect to
the Internet through base stations installed in airports, railway stations, and
other public locations.
ᴥ At home, users can connect devices on their
desktop to synchronize data and transfer files.
Type of Wireless Network
1. Wireless wide area networks (WWANs)
2. Wireless metropolitan area networks (WMANs)
3. Wireless local area networks (WLANs)
4.
Wireless personal
area networks (WPANs)
WWAN
ᴥ WWAN technologies enable users to establish wireless
connections over remote public or private networks. These connections can be
maintained over large geographical areas, such as cities or countries, through
the use of multiple antenna sites or satellite systems maintained by wireless
service providers.
WMAN
ᴥ WMAN technologies enable users to establish
wireless connections between multiple locations within a metropolitan area (for
example, between multiple office buildings in a city or on a university
campus), without the high cost of laying fiber or copper cabling and leasing
lines.
 |
| MAN network |
 |
| Network at metropolitan area |
WLAN
ᴥ Wireless Local Area Networks (WLAN) are
implemented as an extension to wired LANs within a building and can provide the
final few meters of connectivity between a wired network and the mobile user.
ᴥ WLAN technologies enable users to establish
wireless connections within a local area (for example, within a corporate or
campus building, or in a public space, such as an airport). WLANs can be used
in temporary offices or other spaces where the installation of extensive
cabling would be prohibitive, or to supplement an existing LAN so that users
can work at different locations within a building at different times.
WPAN
ᴥ WPAN technologies enable users to establish ad
hoc, wireless communications for devices (such as PDAs, cellular phones, or
laptops) that are used within a personal operating space (POS).
ᴥ A POS is the space surrounding a person, up to a
distance of 10 meters.
Application
• Voice and messaging
>Cell phones, pagers.
>analog or digital standards
– The analog standard
is the Advanced Mobile Phone Service (AMPS).
– Digital standards are
Global System for Mobile Communications (GSM), Time Division Multiple Access
(TDMA), or Code Division Multiple Access (CDMA).
• Hand‐held and other Internet‐enabled
devices
> Internet‐enabled
cell phones and Personal Digital Assistants (PDAs) can connect to the Internet
across a digital wireless network.
>Uses
Wireless Application Protocol (WAP),and WML (Wireless
Markup Language)
ᴥ The majority of current Internet content is not
optimized for these devices; presently, only email, stock quotes, news,
messages and simple transaction oriented services are messages,
transaction‐available.
ᴥ Other limitations include low bandwidth (less
than 14 Kbps), low quality of service, high cost, the need for additional
equipment, and high utilization of devices' battery power. Nevertheless, this
type of wireless technology is growing rapidly with better and more
interoperable products.
• Data Networking
ᴥ Infra Red Transmission
• IrDA (Infrared Data Association) is an industry standard for wireless communication with infrared
light. (Non RF)
• Many laptops sold today are equipped with an
IrDA-compatible transceiver that enables communication with other devices, such
as printers, modems, LANs, or other laptops. The transfer speed ranges from
2400 bps to 4Mbps.
• Requires line of sight transmission
ᴥ Wireless local area networks (WLANs)
·
Wi‐Fi the
underlying technology of wireless local area networks (WLAN)
·
based on the IEEE 802.11 specifications.
·
used for mobile computing devices, such as
laptops, in LANs, increasingly used for more services, including Internet and
VoIP phone access, gaming, and basic connectivity of consumer electronics such
as televisions and DVD players, or digital cameras.
·
Frequency 2.4 GHz
·
Range 100‐300 feet(indoor) 300‐900 feet(outdoor)
ᴥ Broadband wireless access
- is a technology aimed at providing high‐speed wireless access over a wide area from devices such as personal computers to data networks. According to the 802.16‐2004 standard, broadband means 'having instantaneous bandwidth greater than around 1 MHz and supporting data rates greater than about 1.5 Mbit/s'.
- It is planned to be used in the next few years and is estimated to have a range of 50km (30 miles).
ᴥ Bluetooth
- Bluetooth is an industrial specification for wireless personal area networks (PANs).
- Designed for very short range <10 m
- connect and exchange information between devices such as mobile phones, laptops, PCs, printers, digital cameras and video game consoles over a secure, globally unlicensed short‐range radio frequency.
·
Frequency 2.4 GHz,
·
Data speed up to 3Mbps
ᴥ WiMax
· - To extend the range of wireless network.
· - Speed up to 70Mbps.
· - Range 30 miles.
· - Provides access to internet access to fixed
location with larger coverage.
Mobiles Phones 1G
1G is short for first‐generation wireless
telephone technology. This generation of phones and networks is represented by
the brick‐sized analog phones introduced in the 1980’s. Subsequent numbers
refer to newer and upcoming technology.
Mobile Phones 2G
2G phones use digital networks. Going all‐digital
allowed for the introduction of digital data services, such as SMS and email.
2G networks and their digital nature also made it more difficult to eavesdrop
on mobile phone calls.
Mobile Phones 3G
3G networks are an in between standard. 3G is
seen more as pre4G instead of a standard of its own. The advantage 3G networks
have over 2G networks is speed. 3G networks are built to handle the needs of
today’s wireless users. This standard of wireless networks increases the speed
of internet browsing, picture and video messaging, and handheld GPS use.
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| Video call |
Mobile Phones 4G
4G (AKA Beyond 3G) is like the other generations
in that its advantage lies in promised increased speeds in data transmission.
There is currently no formal definition for 4G, but there are objectives. One
of these objectives is for 4G to become a fully IP‐based system, much like
modern computer networks. The supposed speeds for 4G will be between 100 Mbit/s
and 1 Gbit/s.
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