Electronic Instrumentation and Communications

Introduction to Communication System.

Communication involves the transfer of information or intelligence from a source to a recipient via a channel or medium.

• Model of a communication system in block diagram, 

•Source: analogue or digital

•Transmitter: transducer, amplifier, modulator, oscillator, power amp., antenna

•Channel: e.g. cable, optical fibre, free space

•Receiver: antenna, amplifier, demodulator, oscillator, power amplifier, transducer

:Recipient: e.g. person, speaker, computer


Full duplex,half-duplex, and simplex,communication systems.

Simplex

A communications network can provide many types of service. The most basic type of service is known as

simplex. This service provides one-way communication. Examples of this type of service are TV distribution,

and the transmission of burglar alarm messages.

Half-duplex

provides for communication in both directions, but only one direction at a time (not simultaneously).

Typically, once a party begins receiving a signal, it must wait for the transmitter to stop transmitting, before

replying.

An example of a half-duplex system is a two-party system such as a "walkie-talkie" style two-way radio,

wherein one must use "Over" or another previously-designated command to indicate the end of transmission,

and ensure that only one party transmits at a time, because both parties transmit on the same frequency.

Full Duplex :

A full-duplex, or sometimes double-duplex system, allows communication in both directions, and, unlike

half-duplex, allows this to happen simultaneously. 

Land-line telephone networks are full-duplex, since they allow both callers to speak and be heard at the

same time.Examples: Telephone, Mobile Phone, etc.

Nature of Signal Sources

• Introduce time and frequency domain, 

representation of analogue and digital signals.

• Concepts of signal bandwidth and bit rates.

• Model of a communication system in block diagram, examples of full duplex,half-duplex, and simplex,communication systems.

Nature of Signal Sources

• Introduce time and frequency domain, representation of analogue and digital signals.

• Concepts of signal bandwidth and bit rates.

Transmission Media (Channel)

• Signal transmission characteristics of twisted pair cables, coaxial cables,optical fibres, waveguide, radio wave.

Modulation Principles

• Introduction to modulation principles.

Modulation Principles

• Modulation techniques using AM and FM.

• Modulated signal characteristics, spectrum, bandwidth, power.

• Basic modulation and demodulation circuits.

Digital Communication Systems

• Introduction to digital communication systems.

Digital Communication Systems

• Signal digitisation using PCM.

• Binary modulation techniques using ASK, FSK and PSK.

• Application to telephone modem.

Pulse Modulation

• Pulse amplitude modulation, pulse position modulation, pulse width modulation.

• Application to telemetry systems remote control.

Noise Degradations in Signal Transmission

• Effect of noise degradation on communication systems, sources of internal and external noise in receiving system, signal-to-noise ratio, qualitative, comparison of noise performance of AM and FM receivers.

Data Communication Principles

• Asynchronous and synchronous data format.

• RS-232 serial interface, channel coding to combat errors in transmission.

Radio Systems Principles

• Model of a radio system in block diagram, radio wave propagation, antenna, directivity, antenna gain.

• Transmitter : AM transmitter and FM transmitter circuits.

• Radio receiver building blocks, Superheterodyne receiver.

• Image frequency, intermediate frequency, selectivity, sensitivity

Basic Measuring Instrument

• Voltage, current, resistance measuring principles, resistance, inductance,capacitance measurement using

bridges.• Applications in thermal sensors.

Electronic Display Instrument

• Construction of Cathode Ray Tube for oscilloscope and television.

• Oscilloscope operating procedures.

• Liquid crystal display principles.

Signal Generating Instrument

• Introduction to various signals and generator circuits.

Digital Instrument

• Principles of digital counter, time, digital storage oscilloscope, logic analysers.

Digital Instrument

• Data acquisition card. Analogue to Digital converter and Digital to

Analogue converter (ADC and DAC) and virtual instrumentation

Electronic Testing and Fault Finding

• Component Measurement and Tester, circuit measurement calibration procedures.

Electronic Testing and Fault Finding

• General principles and logical approach to fault finding.