Standard

 

ELC 220 – AM and SSB Circuit Analysis

Course Description:

Reviews communication system concepts and emphasizes an in-depth analysis of amplitude modulation and detection methods.  Topics include:  communication concepts, AM/SSB modulation, AM/SSB detection, AM/SSB transmitters, AM/SSB receivers, noise/bandwidth considerations, and multiplexing/ demultiplexing.

 

Competency Areas:

Hours:

 

 

 

Communication Concepts

Class

3

AM/SSB Modulation

D. Lab

2

AM/SSB Detection

P. Lab/O.B.I.

0

AM/SSB Transmitters

Credit

4

AM/SSB Receivers

 

 

Noise/Bandwidth Considerations

 

 

Multiplexing/Demultiplexing

 

 

 

 

 

Prerequisite:  

ELC 119

Corequisite:  

 

 

Course Guide

 

Competency

After completing this section, the student will:

Hours

Class

D. Lab

P. Lab/

O.B.I.

COMMUNICATION CONCEPTS

4

2

0

Block diagrams

Draw simple radio transmitter and receiver system block diagrams.

 

 

 

AM/SSB characteristics

Distinguish between double sideband and single sideband modulation and detection techniques.

 

 

 

Intelligence transmission and reception

Explain how intelligence is impressed upon electromagnetic waves, transmitted through free space, received, and detected.

 

 

 

SSB communications

List the major advantages of SSB communications.

 

 

 

AM/SSB MODULATION

4

3

0

Basic terms

Define the terms carrier mixer, sideband, modulation percentages, over modulation, high-level modulation, low-level modulation, neutralization, balanced modulator, and ring modulator.

 

 

 

Modulation

Calculate the percentage of modulation, upper sideband/lower sideband frequencies, and transmitted power distribution between carrier and sidebands.

 

 

 

Filters

Explain filter use in SSB transmission systems.

 

 

 

AM/SSB DETECTION

4

3

0

Basic terms

Define the terms sensitivity, selectivity, bandwidth, detection, clipping, frequency conversion, supernetroding, AFC, AGC, IF image frequency, local oscillator, and beat frequency oscillator.

 

 

 

Basic circuits

Explain the function in a radio receiver of RF amplifiers, IF amplifiers, and the detector.

 

 

 

AM/SSB TRANSMITTERS

8

9

0

AM system

Draw an AM transmitter block diagram.

 

 

 

Basic circuits

Explain the purpose of the carrier oscillator, buffer amplifier, and power amplifier.

 

 

 

SSB system

Draw an SSB transmitter block diagram.

 

 

 

Basic circuits

Explain the purpose of the balanced modulators and RF carrier oscillator in an SSB transmitter.

 

 

 

 

Demonstrate the use of an oscilloscope and signal generator to align a transmitter.

 

 

 

AM/SSB RECEIVERS

8

9

0

Basic circuits

Explain the function in a radio receiver of RF amplifiers, system alignment.

 

 

 

 

Demonstrate basic test equipment use to align a radio receiver.

 

 

 

Frequency conversion

Describe the function(s) of the first and second mixers in an SSB receiver.

 

 

 

System diagram

Draw a superheterodyne receiver block diagram.

 

 

 

NOISE/BANDWIDTH CONSIDERATIONS

1

2

0

System performance

Define and calculate the signal-to-noise ratio and noise figure of a receiver system.

 

 

 

MULTIPLEXING/DEMULTIPLEXING

1

2

0

Terminology

Define the terms multiplexing and demultiplexing.

 

 

 

 

Explain in general terms the purpose of multiplexed communications

 

 

 

 

Suggested Resources

 

Books:

 

Dungan, F. R.  (1993).  Electronic communications systems: Instructor’s guide.  Albany, NY: Delmar.

Miller, G. M.  (1996).  Modern electronic communications (5th ed.).  Englewood Cliffs, NJ: Prentice Hall.

Roddy, D., & Coolen, J.  (1995).  Electronic communications.  Englewood Cliffs, NJ: Prentice Hall.

Schweber, W. L.  (1995).  Electronic communications systems: A complete course.  Englewood Cliffs, NJ: Prentice Hall.

Tomasi, W.  (1993).  Advanced electronic communications systems (3rd ed).  Englewood Cliffs, NJ: Prentice Hall.

Tomasi, W.  (1993).  Electronic communications systems: Fundamentals through advanced.  Englewood Cliffs, NJ: Prentice Hall.