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Basic Concepts of Wireless
Communication System
Prepared by: Mr. Gilbert De Castro
 Computer Networking
 Data Communication
 Transmission Media
 Distributed System
Objectives
Basic Principle of Networks
Computer network
 Collection of computers
and devices connected
via communications
devices and
transmission
media
 Bunch of computers
hook together in some
way
 Each particular message
is usually routed to a
particular computer
Basic Principle of Networks
Networking
 Is the problem of
delivering a message
from a source to a
destination
 The problem of giving
meaning to these
messages received is
called communication
Use of Computer Networks
 Networks for Companies
 Resource sharing – Saves time and money.
 Dynamic rerouting – Having alternative source of supply
data
Basic Principle of Networks
 Networks for people
 Access to remote information – Great source of
information
 Person-to-person communication
 Interaction between a person and a database
 Person-to-person interaction
 Interactive entertainment
 Network gaming
 Video-on-demand
Basic Principle of Networks
Advantages of networking
 Connectivity and communication
 Data sharing
 Hardware sharing
 Internet access
 Internet access sharing
 Data security and management
 Performance enhancement and balancing
 Entertainment
Basic Principle of Networks
Basic Principle of Networks
Communication channel
 Is a pathway over which
information can be
transferred
 Information sent over a
channel has source (often
called the transmitter), from
which the information
originates
 And destination (often called
the receiver), to which the
information is delivered
Channel
Communication channels
Any communication has a direction associated with it
 Simplex channel – is a channel whose direction of
transmission is unchanging
 Half-duplex channel – is a channel in which the
direction may be reversed, but the transmission does
not occur at the same time
 Full-duplex channel – is a channel that allows
simultaneous exchange in both directions
Basic Principle of Networks
Types of Transmission Technologies
 Point-to-point network – consist of many connections
to individual pairs of machines
 Broadcast networks – all the machines on the
network share a single channel
Basic Principle of Networks
Network Topologies
 Computer networks come in different shapes and
sizes
 The network’s topology can be thought of as its
“shape”, the way the computers on the network are
connected
 Network topologies are categorized into the five
basic types
Basic Principle of Networks
Characteristics of effective data communication
 Delivery
 Accuracy
 Timeliness
Basic Principle of Networks
Components of data communication
 Message
 Sender
 Receiver
 Medium
 Protocols
Basic Principle of Networks
Protocol
 Formal description of set of rule sand conventions
that govern how devices on a network communicate
 Control aspects of data communication, which
include the following:
 How the physical data is built
 How computers connect to the network
 How the data is formatted for transmission
 How the data is sent
 How to deal with errors
Basic Principle of Networks
Network Topologies
Bus network
 A common channel
connect all devices
 All computers and
devices connect to
central cable, or bus
Basic Principle of Networks
Ring network
 All messages travel in a ring,
either in clockwise or
counterclockwise direction
 Cable forms closed ring, or
loop, with all computers and
devices arranged along ring
 Data travels from device to
device around entire ring, in
one direction
Basic Principle of Networks
Star network
 All devices connect to a
central device, called hub
 All data transferred from
one computer to another
passes through hub
Basic Principle of Networks
 Tree network -
Integrates multiple star
topologies together into
a bus
Basic Principle of Networks
 Mesh network – involves
the concept of routes,
where a message is sent
on the network can take
any of several possible
paths from source to
destination
 Popular topologies are
bus, ring, and star
Communications device
 Hardware component that enables a computer to
send and receive data, instructions and information
 Occurs over cables, telephone lines, cellular radio
networks, satellites, and other transmission media
Communication Devices
 Modem
 Network Card
 Gateway
 Router
 Wireless Access Point
 Hub
Modem
• Converts digital signals to analog signals and vice versa
 Dial up modem
 ISDN and DSL modems
 Wireless modem
Network Card
 Adapter card, PC Card, or flash card that enables
computer or device to access network
 Sometimes called network interface card (NIC)
Gateway
 Links network using different protocols
 Contain devices such as protocol translators
Router
 Connects multiple networks and determines the
fastest route for sending data over the network
Wireless Access Point
 Connects wireless communication devices
Hub
• Device that provides central point for cables in
network
Communication Channel
 Transmission media on which data travels in
communications system
 Transmission media - are materials capable of carrying
one or more signals
 Bandwidth - amount of data that can travel over a
communications channel
 Physical Transmission Media
 Wireless Transmission Media
Physical Transmission Media
 Wire, cable, and other tangible materials used
to send communications signals
 Twisted-pair cable
 Coaxial Cable
 Fiber-optic cable
Twisted-pair cable
 Used for telephone systems and network cabling
Coaxial Cable
 Often used for cable television wiring
Fiber-optic cable
 Capable of carrying
significantly more
data at faster speeds than
wire cables
 Less susceptible to
interference (noise) and,
therefore, more secure,
Smaller size (thinner and
lighter)
Wireless transmission media
 Radio Signal
 Microwaves
 Satellites
 IrDA
 Bluetooth
 Wi-Fi
Radio Signal
 Broadcast radio distributes
radio signals over long and
short distances
 Cellular radio is form of
broadcast radio used for
mobile communications
Microwaves
 Earth-based reflective
dish used for microwave
communications
 Must transmit in straight
line with no obstructions
Satellites
 Space station
that receives microwave
signals from earth-based
station, amplifies signals,
and broadcasts signals back
to any number of earth-
based stations
IrDA ( Infrared Data Association)
 Physical specifications communications protocol
standards for the short-range exchange of data over
infrared light waves
Bluetooth
 Short-range radio waves transmit data between
Bluetooth devices
 Short distance transmission of about 30 feet
Wi-Fi
 Wireless Fidelity
 Connecting electronic devices wirelessly
Basic Principle of Networks
Distributed Systems
 There is considerable confusion between a computer
network and a distributed system
 The key distinction is that in a distributed system, the
existence of multiple autonomous computers is
transparent to the user
 The user can type a command to run a program, and it
runs
 It is up to the operating system to choose the best
processor for the application, send the necessary data
and place the result to the proper location
Basic Principle of Networks
Client/Server
 Extension of distributed data
processing wherein it provides
the best of both centralized and
distributed data processing
 Client – issues a request to a
server to ask for work to be
done
 Server – usually a host machine
that provides database,
printing, storage and
communications
Basic Principle of Networks
Types of network design
The networking industry refers to nearly every type of
network as an “area network”.
 Local Area Network (LAN)
 Wide Area Networks (WAN)
Basic Principle of Networks
Local Area Network (LANs)
 Connect network devices
over relatively short
distances
 Usually owned by an
individual or corporation
 Network in limited
geographical area such as
home or office building
Basic Principle of Networks
Wide Area Networks (WANs)
 Span a large physical distance
(geographically-dispersed
collection of LANs) and
mostly owned by any one
organization but rather exist
under collective or distributed
ownership and management
 Network that covers large
geographic area using many
types of media
 Internet is world’s largest
WAN

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Basic concepts of wireless communication system

  • 1. Basic Concepts of Wireless Communication System Prepared by: Mr. Gilbert De Castro
  • 2.  Computer Networking  Data Communication  Transmission Media  Distributed System Objectives
  • 3. Basic Principle of Networks Computer network  Collection of computers and devices connected via communications devices and transmission media  Bunch of computers hook together in some way  Each particular message is usually routed to a particular computer
  • 4. Basic Principle of Networks Networking  Is the problem of delivering a message from a source to a destination  The problem of giving meaning to these messages received is called communication
  • 5. Use of Computer Networks  Networks for Companies  Resource sharing – Saves time and money.  Dynamic rerouting – Having alternative source of supply data Basic Principle of Networks
  • 6.  Networks for people  Access to remote information – Great source of information  Person-to-person communication  Interaction between a person and a database  Person-to-person interaction  Interactive entertainment  Network gaming  Video-on-demand Basic Principle of Networks
  • 7. Advantages of networking  Connectivity and communication  Data sharing  Hardware sharing  Internet access  Internet access sharing  Data security and management  Performance enhancement and balancing  Entertainment Basic Principle of Networks
  • 8. Basic Principle of Networks Communication channel  Is a pathway over which information can be transferred  Information sent over a channel has source (often called the transmitter), from which the information originates  And destination (often called the receiver), to which the information is delivered Channel
  • 9. Communication channels Any communication has a direction associated with it  Simplex channel – is a channel whose direction of transmission is unchanging  Half-duplex channel – is a channel in which the direction may be reversed, but the transmission does not occur at the same time  Full-duplex channel – is a channel that allows simultaneous exchange in both directions Basic Principle of Networks
  • 10. Types of Transmission Technologies  Point-to-point network – consist of many connections to individual pairs of machines  Broadcast networks – all the machines on the network share a single channel Basic Principle of Networks
  • 11. Network Topologies  Computer networks come in different shapes and sizes  The network’s topology can be thought of as its “shape”, the way the computers on the network are connected  Network topologies are categorized into the five basic types Basic Principle of Networks
  • 12. Characteristics of effective data communication  Delivery  Accuracy  Timeliness Basic Principle of Networks
  • 13. Components of data communication  Message  Sender  Receiver  Medium  Protocols Basic Principle of Networks
  • 14. Protocol  Formal description of set of rule sand conventions that govern how devices on a network communicate  Control aspects of data communication, which include the following:  How the physical data is built  How computers connect to the network  How the data is formatted for transmission  How the data is sent  How to deal with errors
  • 15. Basic Principle of Networks Network Topologies Bus network  A common channel connect all devices  All computers and devices connect to central cable, or bus
  • 16. Basic Principle of Networks Ring network  All messages travel in a ring, either in clockwise or counterclockwise direction  Cable forms closed ring, or loop, with all computers and devices arranged along ring  Data travels from device to device around entire ring, in one direction
  • 17. Basic Principle of Networks Star network  All devices connect to a central device, called hub  All data transferred from one computer to another passes through hub
  • 18. Basic Principle of Networks  Tree network - Integrates multiple star topologies together into a bus
  • 19. Basic Principle of Networks  Mesh network – involves the concept of routes, where a message is sent on the network can take any of several possible paths from source to destination  Popular topologies are bus, ring, and star
  • 20. Communications device  Hardware component that enables a computer to send and receive data, instructions and information  Occurs over cables, telephone lines, cellular radio networks, satellites, and other transmission media
  • 21. Communication Devices  Modem  Network Card  Gateway  Router  Wireless Access Point  Hub
  • 22. Modem • Converts digital signals to analog signals and vice versa  Dial up modem  ISDN and DSL modems  Wireless modem
  • 23. Network Card  Adapter card, PC Card, or flash card that enables computer or device to access network  Sometimes called network interface card (NIC)
  • 24. Gateway  Links network using different protocols  Contain devices such as protocol translators
  • 25. Router  Connects multiple networks and determines the fastest route for sending data over the network
  • 26. Wireless Access Point  Connects wireless communication devices
  • 27. Hub • Device that provides central point for cables in network
  • 28. Communication Channel  Transmission media on which data travels in communications system  Transmission media - are materials capable of carrying one or more signals  Bandwidth - amount of data that can travel over a communications channel  Physical Transmission Media  Wireless Transmission Media
  • 29. Physical Transmission Media  Wire, cable, and other tangible materials used to send communications signals  Twisted-pair cable  Coaxial Cable  Fiber-optic cable
  • 30. Twisted-pair cable  Used for telephone systems and network cabling
  • 31. Coaxial Cable  Often used for cable television wiring
  • 32. Fiber-optic cable  Capable of carrying significantly more data at faster speeds than wire cables  Less susceptible to interference (noise) and, therefore, more secure, Smaller size (thinner and lighter)
  • 33. Wireless transmission media  Radio Signal  Microwaves  Satellites  IrDA  Bluetooth  Wi-Fi
  • 34. Radio Signal  Broadcast radio distributes radio signals over long and short distances  Cellular radio is form of broadcast radio used for mobile communications
  • 35. Microwaves  Earth-based reflective dish used for microwave communications  Must transmit in straight line with no obstructions
  • 36. Satellites  Space station that receives microwave signals from earth-based station, amplifies signals, and broadcasts signals back to any number of earth- based stations
  • 37. IrDA ( Infrared Data Association)  Physical specifications communications protocol standards for the short-range exchange of data over infrared light waves
  • 38. Bluetooth  Short-range radio waves transmit data between Bluetooth devices  Short distance transmission of about 30 feet
  • 39. Wi-Fi  Wireless Fidelity  Connecting electronic devices wirelessly
  • 40. Basic Principle of Networks Distributed Systems  There is considerable confusion between a computer network and a distributed system  The key distinction is that in a distributed system, the existence of multiple autonomous computers is transparent to the user  The user can type a command to run a program, and it runs  It is up to the operating system to choose the best processor for the application, send the necessary data and place the result to the proper location
  • 41. Basic Principle of Networks Client/Server  Extension of distributed data processing wherein it provides the best of both centralized and distributed data processing  Client – issues a request to a server to ask for work to be done  Server – usually a host machine that provides database, printing, storage and communications
  • 42. Basic Principle of Networks Types of network design The networking industry refers to nearly every type of network as an “area network”.  Local Area Network (LAN)  Wide Area Networks (WAN)
  • 43. Basic Principle of Networks Local Area Network (LANs)  Connect network devices over relatively short distances  Usually owned by an individual or corporation  Network in limited geographical area such as home or office building
  • 44. Basic Principle of Networks Wide Area Networks (WANs)  Span a large physical distance (geographically-dispersed collection of LANs) and mostly owned by any one organization but rather exist under collective or distributed ownership and management  Network that covers large geographic area using many types of media  Internet is world’s largest WAN