1 1 Know the element in basic communication

1. 1 Know the element in basic communication system At the end of this learning session, student should be able to explain : - Definition Communication System - The elements in communication system - Block diagram of communication system. 1

COMMUNICATION SYSTEM Hanisah/EP 301/JKE/POLISAS/Dis 12 2

COMMUNICATION • DEFINITION: Communication system is a process of transmission, reception and processing the information between two or more locations through transmission medium. • Examples – People-people, people-peoples, – computer-computer, computer-computers – People - computer 3

COMMUNICATION SYSTEM TELECOMMUNICATION • TELE (in Latin) = Far • COMMUNICATION = Process of sending the information between two or more locations through transmission medium. • TELECOMMUNICATION = Process of sending the information between two or more locations through transmission medium at far distance. Telegraph 4

COMMUNICATION SYSTEM TELECOMMUNICATION • Early Telecommunication: In earlier times, telecommunications involved the use of visual signals or audio signals such as; – Smoke signals, Flag signals – Coded drum beats, Lung-blown horns – Visual telegraphy (or Semaphore in 1792) • Modern Telecommunication: In the modern age of electricity and electronics, telecommunications has typically involved; – Telegraph (1839), Telephone(1876), Teletype, Radio, TV – Microwave Communication – Satellite, Radar, Cellular – Data Communication – Internet, Computer communication – Fiber Optic Communication. 5

COMMUNICATION SYSTEM MODEL Claude Shannon’s General Communication Model; message INFORMATION SOURCE signal TRANSMITTER signal TRANSMISSION MEDIUM or CHANNEL RECEIVER message DESTINATION SYSTEM NOISE & INTERFERENCE Figure 1. 1: Basic Block Diagram of an Electronic Communication System 6

ELEMENTS of COMMUNICATION SYSTEM From above Shannon’s basic communication block diagram, there are FIVE (5) elements that must have in basic communication system which are, 1) Information Source 2) Transmitter (Tx) 3) Transmission Medium or Communication Channel 4) Receiver (Rx) 5) Destination 7

ELEMENTS of COMMUNICATION SYSTEM 1. Information Source • The original source that generate the information (audio, text, image or video) that need to be transferred to Receiver. • The information that have been generated by source could be an analog form (human voice, audio) or digital form (binary coded numbers, alphanumeric codes). • Examples: people, computer, hand phone, electronic devices 8

ELEMENTS of COMMUNICATION SYSTEM 2. Transmitter • A collection of one or more electronic devices or circuits that converts the original source information to a form more suitable for transmission over a particular transmission medium. • Includes the modulation, multiplexing and encoding process. • Examples: Modulator, Multiplexer, Transducer, Encoder, Light Source etc. 9

ELEMENTS of COMMUNICATION SYSTEM 3. Transmission Medium / Channel • Transmission Medium or Communication Channel is a media/link/path that capable to transfer the electronic signal from Transmitter to receiver. • Examples: Twisted Pair Cable, Coaxial Cable, Fiber Optic Cable, Waveguide, Microstrip, Free Space, etc. Twisted Pair Cable 10

ELEMENTS of COMMUNICATION SYSTEM Coating Insulator Cladding Inner Conductor Core Inner Conductor Fiber Optic Cable Waveguide Outer Conductor Coaxial Cable Microstrip 11

ELEMENTS of COMMUNICATION SYSTEM 4. Receiver • A collection of one or more electronic devices or circuits that accept the transmitted signals from the transmission medium and then convert back to their original information form. • Includes the demodulation, demultiplexing and decoding process. • Examples: Demodulator, Demultiplexer, Transducer, Decoder, Photo detector, etc. 12

ELEMENTS of COMMUNICATION SYSTEM 5. Destination • Anything that receive the transmitted information and capable to store them. • Examples: people, computer, hand phone, electronic devices. 6. System Noise • Noise is any unwanted electrical signals that interfere with the information signal. • Examples: Atmospheric noise, Thermal Noise, Man-made Noise, Cosmic Noise, Internal Noise etc. 13

EXAMPLE a) Data Communication System Information Source Transmitter Transmission Medium or Channel Receiver Destination b) Telephony Communication System 14

Information, Message, & Signal Claude Shannon’s General Communication Model; message INFORMATION SOURCE info signal TRANSMITTER signal TRANSMISSION MEDIUM or CHANNEL message RECEIVER DESTINATION info SYSTEM NOISE & INTERFERENCE Figure 1. 1: Basic Block Diagram of an Electronic Communication System 15

Information, Message, & Signal q Information • Information = knowledge = intelligence. • Information is an original source information which do NOT processed yet by transmitter or do NOT converted into signal. • It can be stored in people or any devices like computer, digital camera, video camera, recorder etc. • Examples: audio, alphanumeric, text, image, video. q Message • Message represents the content of Information. 16

Information, Message, & Signal q Signal • Signal is a converted information into time-varying or spatial-varying quantity that could be measured. • Signal can be an electric current, light or electromagnetic wave which is used to convey data from one place to another. • A signal may be expressed as a function of time or frequency. • When a signal is expressed as a function of time, there are two basic types of signals. i. Digital Signal (Discrete-time signal) ii. Analog Signal (Continuous-time signal) 17

Information, Message, & Signal DIGITAL SIGNAL A discrete or finite signal that generates and process data in form of zeroes and ones (0 s and 1 s). It has finite (countable) set of amplitudes. For example; binary-encoded digit, alphanumeric codes, computer-generated data, digitally encoded analog signals etc. ANALOG SIGNAL A continuous or infinite signal that generates continuous values, leading to continuous wave pattern. It has infinite (uncountable) of amplitudes. For example; human voice, audio etc. 18

Information, Message, & Signal Continuous (infinite) amplitude levels Discrete (countable) amplitude levels 19