itgd3101modern telecommunications lecture-1- pulse code modulation week 1- s1/ 2009-2010 dr. anwar...

ITGD3101Modern Telecommunications

Lecture-1- Pulse Code Modulation

week 1- S1/ 2009-2010

Dr. Anwar Mousa

University of PalestineFaculty of Information Technology

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DATE TOPICSWeek 1 Course description-Sampling Theorem

Week 2 Pulse Code Modulation

Week 3 Pulse Code Modulation

Week 4 Principles of Data transmission- Digital communications systems

Week 5 Line coding

Week 6 Line coding

Week 7 Pulse shaping

Week 8 Mid-Term Exam

Week 9 Detection-Error Probability

Week 10 M-ary communications

Week 11 Optimum Threshold Detection

Week 12 Signal space

Week 13 Optimum receiver

Week 14 Error Correcting Codes Linear Block Codes

Week 15 FINAL EXAM

Week 16 FINAL EXAM

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Instructor InformationOffice location:

Office hours:Email: anwar_mousa@yahoo.com

Phone: 1115

Research interests:

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Textbook and SoftwareRequire textbook:

B.P. Lathi, Modern Digital and Analog Communication Systems, 3rd edition, Oxford University Press, 1998

Recommended readings Digital communications: J. Proakis, Digital Communications

Random process: G.R. Grimmett and D.R. Stirzaker, Probability and Random Processes

Estimation and detection: H.V. Poor, An introduction to Signal Detection and Estimation

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Homework, Project, and ExamHomework

1 assignment per week

Exams Two exams: Midterm and Final

Participations Attendance and Feedback

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Teaching StylesSlides plus Whiteboard

Slides can convey more information in an organized way

Whiteboard is better for equations and prevents you from not coming.

Course Website

Print handouts with 3 slides per page before you come

Homework assignment and solutions

Feedback

Too fast, too slow

Presentation

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Course Outline

(Chapter 6) Sampling and Pulse Code Modulation Sampling Theorem

Pulse Code Modulation (PCM)

(Chapter 7)

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Course Outline

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Course Outline

(Chapter 13) Behavior of Digital communication

systems in the presence of Noise Optimum Threshold Detection

Optimum Binary Receiver

M-ary Communications

(Chapter 14)

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Course Outline

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Course Outline

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Contents

Sampling theoremQuantization Pulse Code Modulation

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Aperiodic signal representation by Fourier Transform

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Today, we are going to talk about:

The first important step in any DCS:

Transforming the information source to a form compatible with a digital system

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EncodeTransmit

PulsemodulateSample Quantize

Demodulate/Detect

Channel

ReceiveLow-pass

filterDecode

PulsewaveformsBit stream

Format

Format

Digital info.

Textual info.

Analog info.

Textual info.

Analog info.

Digital info.

source

sink

Formatting and transmission of baseband signal

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Format analog signals

To transform an analog waveform into a form that is compatible with a digital communication, the following steps are taken:

1. Sampling

2. Quantization and encoding

3. Baseband transmission

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Sampling theorem

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Sampling theorem

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Sampling theorem

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Sampling theorem

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Sampling theorem

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Sampling theorem

Sampling theorem: A bandlimited signal with no spectral components beyond , can be uniquely determined by values sampled at

uniform intervals of

The sampling rate, is called Nyquist rate.

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Sampling theorem

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Sampling theorem

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Pulse Code Modulation (PCM).

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Pulse Code Modulation (PCM).

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Pulse Code Modulation (PCM).

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Quantization example

t

Ts: sampling time

x(nTs): sampled valuesxq(nTs): quantized values

boundaries

Quant. levels

111 3.1867

110 2.2762

101 1.3657

100 0.4552

011 -0.4552

010 -1.3657

001 -2.2762

000 -3.1867

PCMcodeword 110 110 111 110 100 010 011 100 100 011 PCM sequence

amplitudex(t)

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Pulse Code Modulation (PCM).

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Pulse Code Modulation (PCM).

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Pulse Code Modulation (PCM).

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Advantages of Digital Communications

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Advantages of Digital Communications

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Advantages of Digital Communications

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Summary

We have studies the following topics:Sampling theoremQuantization Pulse Code Modulation