ECE 4600Communication Systems

Dr. Bradley J. BazuinAssociate Professor

Department of Electrical and Computer EngineeringCollege of Engineering and Applied Sciences

Course Topics

• Course Introduction and Overview• Review of selected topics from Fourier transforms, linear systems,

convolution and filtering. (ABET a,k)• Amplitude Modulation, Signal, Spectrum and Circuits. (ABET a-g,j,k)• Phase and Frequency Modulation, Signals, Spectrum, Circuits, Bessel

Functions, Phase-locked loops. (ABET a-g,j,k)• Noise in analog modulation (ABET a-g,j,k)• Digital Communications, Amplitude Shift Keying, Phase Shift Keying,

Optimum Receiver, Decision Regions. (ABET a-g,j,k)• Noise in digital communications (ABET a-g,j,k)• Selected advance topics from Information theory, Channel Coding, or

Coded Modulation (ABET a-g,j,k)

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Course Objectives

• To give students the ability to analyze analog and digital communication systems performance, and design subsystems and circuits.

• To provide communications fundamentals required for careers related to communications.

• To provide communications fundamentals required for more advanced communications training.

– You are ready for ECE6640 Digital Comm..

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Final Exam

• Monday, 14 December, 10:15 AM• Open Book, Open Notes• 2009: 8 questions, 80 points• 2008: 8 questions, 80 points• 2007: 8 questions, 80 points• 2006: 9 (1 free-bee) questions, 90 points

• Comprehensive– Study past exams and new material

Exam Content

• Fourier Transforms• Transmission Loss, Cascaded Gains and Cascaded Noise Figures• Sketching signal waveforms: AM, PM, FM, ASK, PSK, FSK

– In time, in phase, in frequency• Modulation type equations, modulators, demodulators• Signal Baseband and Bandpass Bandwidths: AM, PM, FM, ASK, PSK, FSK• Filters: LPF and BPF

– Band edge attenuation, stopband attenuation, transition band• Digital Modulation Bit-error-rates, Probability of error, etc.

– SNR to Eb/No, Q-function BER• Optimal Digital Modulation Detection, Filters/Correlators, and Thresholds

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Exposed to

• Real world communication system engineering concepts, problems, and design approaches.

– signals in time and frequency,– transmitters and receivers (idealized block diagrams), – signal propagation (including path loss, receiver gain and noise

figure), – receiver operating characteristics (including receiver sensitivity,

dynamic range, SNR and Eb/No), – signal bandwidths (baseband and RF bandpass), and – filters (passband, transition bands, stop band, and simple design).

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Take-Home Final

• Due today, 11 December by 5 PM

• Waveform File is on the web site for problem #1

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Spectrum Close Up

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Frequency (Hz) 1040 2 4 6 8 10 12

Pow

er (d

B)

-120

-100

-80

-60

-40

-20

0Sequenctial FFTs of the ModSig Waveform

Fs = 11,025 Fis = 264,600

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Textbook/Materials

• A. Bruce Carlson, P.B. Crilly, J.C. Rutledge, Communication Systems, 4th ed., McGraw-Hill, 2002. ISBN: 0-07-011127-8

• MATLAB, Student Edition• MATLAB Signal Processing Toolbox

– The MATH Works,MATLAB ($99) and Signal Processing Toolbox ($29)http://www.mathworks.com/

• LTSpice/SwitcherCAD III – Linear Technologyhttp://www.linear.com/company/software.jsp

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Course/Text OverviewChapter 1: Introduction (1 Lecture)

1.1 Elements and Limitations of Communications Systems

1.2 Modulation and Coding

1.3 Historical Perspective and Societal Impact

1.4 Prospectus

Chapter 2: Signals and Spectra (2 Lectures)

2.1 Line Spectra and Fourier Series

2.2 Fourier Transforms and Continuous Spectra (2.1)

2.3 Time and Frequency Relations (2.2)

2.4 Convolution (2.3)

2.5 Impulses and Transforms in the Limit (2.4)

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Course/Text Overview (2)Chapter 3: Signal Transmission and Filtering (3.5 Lectures)

3.1 Response of LTI Systems (2.4)

3.2 Signal Distortion in Transmission (3.1)

3.3 Transmission Loss and Decibels (3.2)

3.4 Filters and Filtering (3.3)

3.5 Quadrature Filters and Hilbert Transforms (3.4)

3.6 Correlation and Spectral Density (3.3)

Chapter 4: Linear CW Modulation (2.5 Lectures) 4.1 Bandpass Signals and Systems (3.4)

4.2 Double-Sideband Amplitude Modulation (4.1)

4.3 Modulators and Transmitters (4.2)

4.4 Suppressed-Sideband AmplitudeModulation (3.5, 4.3)

4.5 Frequency Conversion and Demodulation (4.4)

Exam #1

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Course/Text Overview (3)Chapter 5: Exponential CW Modulation (4 Lectures)

5.1 Phase and Frequency Modulation (4.3)

5.2 Transmission Bandwidth and Distortion (5.1)

5.3 Generation and Detection of FM and PM (4.5, 5.2)

5.4 Interference (5.3)

Chapter 6: Sampling and Pulse Modulation (2 Lectures) 6.1 Sampling Theory and Practice (4.2)

6.2 Pulse-Amplitude Modulation (6.1)

6.3 Pulse-Time Modulation (6.2)

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Course/Text Overview (4)Chapter 7: Analog Communication Systems (4 Lectures)

7.1 Receivers for CW Modulation (5.3)

7.2 Multiplexing Systems (5.3, 6.1)

7.3 Phase-Lock Loops (7.1)

7.4 Television Systems (7.1)

Exam #2

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Course/Text Overview (5)Chapter 8: Probability and Random Variables (1 Lecture)

ECE 3800 Review Material

8.1 Probability and Sample Space

8.2 Random Variables and Probability Functions (8.1)

8.3 Statistical Averages (2.3, 8.2)

8.4 Probability Models (8.3)

Chapter 9: Random Signals and Noise (1 Lecture)

ECE 3800 Review Material – Incorporated Previously

9.1 Random Processes (3.6, 8.4)

9.2 Random Signals (9.1)

9.3 Noise (9.2)

9.4 Baseband Signal Transmission with Noise (9.3)

9.5 Baseband Pulse Transmission with Noise (9.4)

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Course/Text Overview (6)Chapter 10: Noise in Analog Modulation Systems (3 Lectures)

10.1 Bandpass Noise (4.4, 9.2)

10.2 Linear CW Modulation with Noise (10.2)

10.3 Exponential CW Modulation with Noise (5.3, 10.2)

10.4 Comparison of CW Modulation Systems (9.4, 10.3)

10.5 Phase-Lock Loop Noise Performance (7.3, 10.1)

10.6 Analog Pulse Modulation with Noise (6.3, 9.5)

Chapter 11: Baseband Digital Transmission (3 Lectures) 11.1 Digital Signals and Systems (9.1)

11.2 Noise and Errors (9.4, 11.1)

11.3 Bandlimited Digital PAM Systems (11.2)

11.4 Synchronization Techniques (11.2)

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Course/Text Overview (7)Not Covered

Chapter 12: Digitization Techniques for Analog Messages and Networks

12.1 Pulse-Code Modulation (6.2, 11.1)

12.2 PCM with Noise (11.2, 12.1)

12.3 Delta Modulation and Predictive Coding (12.2)

12.4 Digital Audio Recording (12.3)

12.5 Digital Multiplexing (12.1)

12.6 Computer Networks (12.5)

Chapter 13: Channel Coding and Encryption

13.1 Error Detection and Correction (11.2)

13.2 Linear Block Codes (13.1)

13.3 Convolutional Codes (13.2)

13.4 Data Encryption (13.1)

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Course/Text Overview (8)Chapter 14: Bandpass Digital Transmission (4 Lectures)

14.1 Digital CW Modulation (4.5, 5.1, 11.1)

14.2 Coherent Binary Systems (11.2, 14.1)

14.3 Noncoherent Binary Systems (14.2)

14.4 Quadrature-Carrier and M-ary Systems (14.2)

14.5 Trellis-Coded Modulation

Chapter 15: Spread Spectrum Systems (1 Lectures, as time permits)

15.1 Direct Sequence Spread Spectrum (14.2)

15.2 Frequency Hop Spread Spectrum (15.1)

15.3 Coding (15.1)

15.4 Synchronization (7.3)

15.5 Wireless Telephone Systems (15.1)