Principles of Electronic Communication Systems: Module 1

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Module 1:

Principles of Electronic Communication System

COMMUNICATION

Convey information

Exchange ideas

Process of transferring information (Source – User)

Barriers are language and distance

Methods of Communication

Face to face

Signals

Written Words

Electrical Innovation (Telephone, Radio, TV, Computer)

Communication Systems

Transmitter

Channel or Medium

Receiver

*Noise degrades or interferes with transmitted information.

Transmitter

Collection of electronic components and circuits

Converts the electrical signal to a signal for transmission over a given medium

Oscillators, amplifiers, tuned circuits and filters, modulators etc.

Communication Channel

Medium where the electronic signal is sent from one place to another

Types of Media include:

Electrical conductor

Optical Media

Free Space

System-specific media (water is medium for sonar)

Receiver

Collects or accepts the transmitted message from the channel

Converts the message back into a form understandable by human

Contains amplifiers, oscillator, mixers etc.

Transceiver

Both send and receive data

Telephones, Fax Machine, Handheld CB Radios, Cell Phones and Computer modems

Attenuation

Also known as degradation

Exist in all media wireless transmission

Proportional to the square distance between the transmitter and receiver

Noise

Random

Undesirable electronic energy

Interferes with the transmitted message

TYPES OF ELECTRONIC COMMUNICATION

Simplex

Simplest method of electronic communication

Radio, TV Broadcasting, Beeper

Half Duplex

Two-way Communication

Only one party transmits at a time

Police, military, radio transmission, amateur radio, family radio

Full Duplex

Two-way Communication

Can talk and listen Simultaneously

TYPES OF ELECTRONIC SIGNAL

Analog Signal

Smoothly and continuously varying voltage or current

Sine wave, voice, Video(TV)

Digital Signal

Change in steps or in discrete increments

Uses binary or two-state codes

Telegraph(Morse Code), Continous wave (CW) code, Serial binary code