Wireless communication is the transfer of information between points without wires, using electromagnetic waves over defined channels. It offers benefits like mobility and cost savings but faces challenges such as security vulnerabilities and interference. Various wireless systems include cellular, satellite, and Bluetooth, each with distinct characteristics and applications.

1. WIRELESS COMMUNICATION
OR
UNGUIDED MEDIA
BY: SCIENCE VILLA

2. WHAT IS WIRELESS COMMUNICATION ?
• In layman language it is communication in which information is transferred
between two or more points without any wire

3. WHAT IS WIRELESS COMMUNICATION ?
• Transmitting/receiving voice and data using electromagnetic waves in open
space
• The information from sender to receiver is carried over a well defined channel
• Each channel has a fixed frequency bandwidth & capacity(bit rate)
• Different channels can be used to transmit information in parallel and
independently

4. HISTORY OF WIRELESS COMMUNICATION ?
• James Clerk Maxwell (1831–1879)
• Scottish, Professor of physics, King’s College (London) and Cambridge University
• Formulated the theory of electromagnetism from 1865 to 1873
• His work established the theoretical foundation for the development of
wireless communications.

5. TIMELINE OF WIRELESS COMMUNICATION
DEVELOPMENT

6. WHY WIRELESS COMMUNICATION
• Freedom from wires
• No cost of installing wires or rewiring
• No bunches of wires running here and
there
• “Auto magical” instantaneous
communications
• Without physical connection setup, e.g.,
Bluetooth, WiFi
• Global Coverage
• Battlefield, vehicles, outer space
• Stay Connected – Roaming allows
flexibility to stay connected anywhere
and any time – Rapidly growing market
attests to public need for mobility and
uninterrupted access
• Flexibility – Services reach you
wherever you go (Mobility). E.g, you
don’t have to go to your lab to check
your mail – Connect to multiple devices
simultaneously

7. HOW COMMUNICATION TAKES PLACE

8. CHALLENGES
• Efficient Hardware
• Low power Transmitters, Receivers
• Low Power Signal Processing Tools
• Efficient use of finite radio spectrum
• Cellular frequency reuse, medium access
control
• Protocols / Integrated services
• voice, data, multimedia over a single
network
• Service differentiation, priorities, resource
• Sharing,...
• Fading
• Multipath
• Higher probability of data corruption
• Hence, need for stronger channel codes
• Need for stronger Security mechanisms
• Privacy, authentication,…

9. GROWTH : TECHNOLOGY TAKE-UP TIME TO 50M
USERS

10. Advantages
• Working professionals can work and access
Internet anywhere and anytime without
carrying cables or wires wherever they go
• A wireless communication network is a
solution in areas where cables are
impossible to install (e.g. hazardous areas,
long distances etc.)
• Wireless networks are cheaper to install
and maintain
Disadvantages
• Has security vulnerabilities
• High costs for setting the infrastructure
• Unlike wired communication, wireless
communication is influenced by physical
obstructions, climatic conditions, interference
from other wireless devices

11. TYPES OF WIRELESS COMMUNICATION
• RADIO TRANSMISSION
Easily generated, Omni-directional , travel long distance , easily penetrates buildings
• PROBLEMS
Frequency dependent , relatively low bandwidth for data communication , tightly
licensed by government
• MICROWAVE TRANSMISSION
Widely used for long distance communication , relatively inexpensive.
• PROBLEMS
Don’t pass through buildings , weather and frequency dependent.

12. TYPES OF WIRELESS COMMUNICATION
• INFRARED AND MILIMETER WAVES
Widely used for short range communication , unable to pass through solid objects ,
used for indoor wireless LANs , not for outdoors
• LIGHT WAVE TRANSMISSION
Unguided optical signal such as laser , unidirectional , easy to install , no license
required
• PROBLEMS
unable to penetrate rain or thick fog , laser beam can be easily diverted by air

13. CURRENT WIRELESS SYSTEMS
• CELLULAR SYSTEM
• WIRELESS LANs
• SATELLITE SYSTEM
• PAGING SYSTEM
• PANs(BLUETOOTH)

14. WHAT IS CELLULAR SYSTEM
• Wireless communication technology in which several small
exchanges (called cells) equipped with low-power radio
antennas (strategically located over a wide geographical area)
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

15. COMMUNICATION B/W BASE STATION & MOBILES IS DEFINED BY
THE STANDARD COMMON AIR INTERFACE (CAI)
• Forward voice channel (FVC)
Voice transmission from base station to mobile
• Reverse voice channel (RVC)
Voice transmission from mobile to base station
• Forward control channels (FCC)
Initiating mobile call from base station to mobile
• Reverse control channel (RCC)
Initiating mobile call from mobile to base station

16. CELLULAR TELEPHONE SYSTEMS
• Provide connection to the PSTN for any user location within the radio range
of the system.
• Characteristic
Large number of users
Large Geographic area
Limited frequency spectrum
Reuse of the radio frequency by the concept of “cell’’
• Basic cellular system: mobile stations, base stations, and mobile switching
center

17. CORDLESS TELEPHONE SYSTEMS
• Cordless telephone systems are full duplex communication systems
• First generation cordless phone
in-home use
communication to dedicated base unit
few tens of meters
• Second generation cordless phone
outdoor
combine with paging system
few hundred meters per station

18. EXAMPLES OF MOBILE RADIO SYSTEMS
• Examples
Cordless phone
Remote controller
Hand-held walkie-talkies
Pagers
Cellular telephone
Wireless LAN
• Mobile - any radio terminal that could be moves during operation
• Portable - hand-held and used at walking speed
• Subscriber - mobile or portable user

19. CLASSIFICATION OF MOBILE RADIO TRANSMISSION
SYSTEM
• Classification of mobile radio transmission system
Simplex: communication in only one direction
Half-duplex: same radio channel for both transmission and reception (push-to-talk)
Full-duplex: simultaneous radio transmission and reception (FDD, TDD)
• Frequency division duplexing uses two radio channel
Forward channel: base station to mobile user
Reverse channel: mobile user to base station
• Time division duplexing shares a single radio channel in time

20. WIRELESS LOCAL AREA NETWORK (WLAN)
• WLAN connect local computers
• Range (100 m) confined region
• Break data into packets
• Channel access is shared
• Backbone internet provides best service
• Poor performance in some application like videos
• Low mobility

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

22. PAGING SYSTEM
• Broad coverage for short messages
• Message broadcast from all base stations
• Simple terminals
• Optimized for one way transmission
• Answer back hard
• Overtaken by cellular

23. PAGING SYSTEM
• Conventional paging system send brief messages to a subscriber
• Modern paging system: news headline, stock quotations, faxes, etc
• Simultaneously broadcast paging message from each base station
• Large transmission power to cover wide area

24. WHAT IS BLUETOOTH
• Bluetooth is a method for data
communication that used short range
radio links to replace cables between
computers and their connected units
• Named on – Danish king harald
Bluetooth & Developed in Scandinavia
• Bluetooth uses a technique called
spread spectrum frequency hopping
• Bluetooth networking transmits data via
low power radio waves. It communicates
on a frequency of 2.45 gigahertz
• Bluetooth doesn't require line of sight
between communicating devices
• Bluetooth can connect up to eight
devices simultaneously

25. WIRELESS SYSTEMS : RANGE COMPARISON

26. FUTURE WIRELESS SYSTEMS
• Ad hoc wireless networks
• Sensor networks
• Distributed control networks
• Ultra Wideband (UWB) Systems

27. AD-HOC NETWORKS WANET
• Peer-to-peer communications
• No backbone infrastructure
• Routing can be multihop
• Topology is dynamic
• Fully connected with different link SINRs

28. DISTRIBUTED CONTROL OVER WIRELESS LINKS
• Packet loss and/or delays impacts controller performance
• Controller design should be robust to network faults
• Joint application and communication network design

29. DISTRIBUTED CONTROL OVER WIRELESS LINKS
• A wireless sensor network (WSN) (sometimes called a wireless sensor and
actuator network (WSAN) are spatially distributed autonomous sensors to
monitor physical or environmental conditions, such as temperature, sound,
pressure, etc. and to cooperatively pass their data through the network to a
main location

30. ULTRA WIDE BAND SYSTEMS
• Ultra Wide Band Systems
• Ultra Wide Band (UWB) is an emerging wireless
• Communications technology that can transmit data at around 100 Mb/s (up to 1000
Mb/s)
• UWB transmits ultra-low power radio signals with very narrow pulses (nanosecond).
• Because of its low power requirements, UWB is very difficult to detect (hence secure)

31. ULTRA WIDE BAND SYSTEMS
• Why UWB?
• Exceptional multi-path immunity
• Low power consumption
• Large bandwidth
• Secure Communications
• Low interference
• No need for a license to operate
• Next generation communication system

32. ULTRA WIDE BAND SYSTEMS

33. LIFI (LIGHT FIDELITY)
• LIFI is transmission of data through illumination by taking the fiber out of fiber
optics by sending data through LED light bulb
• This varies in intensity faster than human eye can follow
• It is the fast and cheap wireless communication system which is optical version
of WIFI

34. THANKS
GET MORE STUFF AT:
HTTPS://WWW.SLIDESHARE.NET/AHSANRAHIM1/
HTTPS://WWW.YOUTUBE.COM/CHANNEL/UCKVVCEV1RGXLZ0GEESBQNVG