ABOUT WIRELESS COMMUNICATION

1. Submitted to
FAHMIIDA HOSSAIN TITHI
Assistant professor,
Department of electrical and electronics
engineering
Submitted by:
NAME ID
MEHEDI HASAN------------------143-33-2159
MD HASIBUL ALAM--------------143-33-2227
MUTTAKIN HOSSAIN -------143-33-2150
PRITOM SAHA --------------143-33-2279
Sec: A
Department of electrical and electronics engineering
Welcome to discussion on
“WIRELESS COMMUNICATION”

2. What is wireless communication?
•Wireless communication is the transfer of information or power
between two or more points that are not connected by an
electrical conductor. The most common wireless technologies
use radio.

3. Wireless Communications History
•Ancient Systems: Smoke Signals, Carrier Pigeons
•Radio invented in the 1880s by Marconi
•Many sophisticated military radio systems were developed during
and after WW2
•Cellular has enjoyed exponential growth since 1988, with more
than 2 billion users worldwide today
•Ignited the recent wireless revolution, 1980-2003
•Growth rate tapering off
•Is there a future for wireless?
Bell and Tainter's
photophone, of 1880.

4. Types of wireless communication
1.RADIO TRANSMISSION:-
easily generated , travel long distance , easily penetrates buildings.
• PROBLEMS:- frequency dependent , relatively low bandwidth for
data communication , tightly licensed by government.
2.MICROWAVE TRANSMISSION:-
widely used for long distance communication , relatively inexpensive.
• PROBLEMS:- don’t pass through buildings , weather and frequency
dependent.

5. TYPES OF WIRELESS COMMUNICATION?
3.INFRARED AND MILIMETER WAVES:-
Widely used for short range communication , used for indoor wireless LANs , not for outdoors.
PROBLEMS:-Suffer from absorption by fog , dust and smoke.
4.LIGHT WAVE TRANSMISSION:-
unidirectional , easy to install , no license required.
PROBLEMS:- unable to penetrate rain or thick fog , laser beam can be easily diverted by air.

6. ADVANTAGE OF WIRELESS COMMUNICATION
1. Working professionals can work and access Internet anywhere and
anytime without carrying cables or wires wherever they go.
2. A wireless communication network is a solution in areas where cables are
impossible to install .
3. Wireless networks are cheaper to install and maintain

7. DISADVANTAGE OF WIRELESS COMMUNICATION
1.Has security vulnerabilities.
2.High costs for setting the infrastructure.
3.Unlike wired communication, wireless communication is influenced by physical
obstructions, climatic conditions, interference from other wireless devices

8. Current Wireless Systems
1.Bluetooth
2. Cellular systems
3.Wireless LANs
4.Satellite Systems
5.Paging Systems
6.Ultra wideband Radios

10. WHAT IS BLUETOOTH?
Bluetooth wireless technology is an open specification for a
low-cost, low-power, short-range radio technology for ad-hoc
wireless communication of voice and data anywhere in the
world.

11. Bluetooth

12. What is Cellular systems?
Wireless communication technology in which several small
exchanges (called cells) equipped with low-power
radio antennas are interconnected through a
central exchange. As a receiver (cell phone)
moves from one place to the next,
its identity, location, and radio frequency is
handed-over by one cell to another without
interrupting a call.

13. Properties of Cell structure
•Typical Cell sizes
• some cites few hundred meters
• country side few tens of kilometers
•Advantages of cell structures:
•more capacity due to frequency Reusage
•less transmission power needed
•more robust, tolerate failures
•Problems:
•fixed network needed for the base stations
•handover necessary
•interference with other cells

14. WHAT IS WLAN?
A wireless local area
network (WLAN) is a
wireless computer
network that links two or
more devices using a
wireless distribution
method (often
spread-spectrum or
OFDM radio) within a
limited area such as a
home, school, computer
laboratory, or office
building.

15. Wireless Local Area
Networks (WLANs)
● WLANs connect “local” computers (100m range)
● Breaks data into packets
● Channel access is shared (random access)
● Backbone Internet provides best-effort service
● Poor performance in some apps (e.g. video)
● Low mobility
Internet
Access
Point

16. Satellite Systems
•Global coverage
•Optimized for good transmission
•Expensive base stations.
•Voice and data transmission
•Telecommunication application
•GPS , global telephone connection
•TV broadcasting , military , weather broadcasting

17. Paging Systems
•Broad coverage for short messaging
•Message broadcast from all base stations
•Simple terminals
•Optimized for 1-way transmission
•Answer-back hard
•Overtaken by cellular

18. THANKS TO ALL