ECE 4221 MO BI L E CO MMUNI CAT I O NS

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Course Objectives

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1. To develop understanding of terrestrial wireless communications

2. To develop an understanding of principles of wireless propagation channels

3. To introduce modulations and diversity in fading channels.

4. To introduce channel coding and error control techniques

5. To expose students to recent developments of mobile communication systems

6. To expose students to computer simulation tools to enhance their understanding of mobile communication systems

OBE (Outcome Based Education)

Learning Outcomes

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Describe basic elements of mobile communication systems.

Quantify the effect of wireless propagation channel

Compare various digital modulation and diversity techniques

Describe the principles of channel coding

Perform simple analysis on system coverage and capacity

Function effectively as group member/leader

Upon completion of this course, students should be able to:

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Content outline of the course / module and the SLT per topic

Content outline of the course / module and the SLT per topic

Weeks Topics Learning

Hours

Task/

Reading

1, 2 Introduction to Mobile Wireless Communications Applications and Requirements of Wireless Services, History Technical Challenges of Wireless Communications Noise- and Interference-limited Systems Structure of Wireless Communication Link

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Chapter 1

Chapter 2

Chapter 3

Chapter 10

3, 4, 5, 6 Wireless Propagation Channels Propagation Mechanisms: Free-space, Reflection, Diffraction, Statistical Description: Two-path Model, Small-scale fading, Large-scale fading Channel Models: Narrowband Model, Wideband Model

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Chapter 4

Chapter 5

Chapter 7

7, 8, 9 Modulation and Diversity Important Modulation Formats, Model for Channel and Noise, Error Probability in Flat Fading Diversity: Microdiversity, Macrodiversity, Combination of Signals

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Chapter 11

Chapter 12

Chapter 13

10 Channel Coding and Information Theory

Fundamental of Coding and Information Theory 3 Chapter 14

11, 12 Multiple Access and System Design Multiple Access: FDMA, TDMA, Packet, CDMA, Duplexing Cellular Principles

6 Chapter 17

13, 14 Standardized Wireless Systems Cognitive Radio, 2G, 3G, Wimax, LTE 6 Chapter 21

Outline

Statistical Description of the Wireless Channel (Ch5)

Large-scale fading

Two-Path Model

Small-scale fading

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What do we know so far

about propagation losses? 6

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In many circumstances, it is too complicated to describe all reflection,

diffraction, and scattering processes that determine the different Multi Path

Components (MPCs).

Rather, it is preferable to describe the probability that a channel parameter

attains a certain value.

The most important parameter is channel gain, as it determines received

power or field strength; it will be at the center of our interest in this chapter.

Note that we talk of channel gain (and not attenuation) because it is directly proportional to receive

power (receive power is transmit power times channel gain); of course, this gain is smaller than unity.

In the following, we often assume unit transmit power and use receive power and channel gain interchangeably.

Statistical Description of the Wireless Channel

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The propagation loss will

change due to movements.

In this chapter, we are going to approach these variations from

statistical point of view.

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Small scale fading: Very short distance, power fluctuates (about one wavelength)

around a mean value, due to MPCs.

Large scale fading: Mean power, average about 10 wavelengths or more, itself

shows fluctuations, due to shadowing large objects

A S H O R T R E V I S I O N

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Radio Signals and

Complex Notation

Simple model of a radio signal 11

IQ Modulator 12

Interpreting the Complex Notation 13

ASK, PSK and FSK 14

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channel attenuation and phase behavior are going to discuss.

s(t)

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Large-scale Fading

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Log-normal distribution 18

Fading Margin 19

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Whats the relationship between

F.M and Probability

of outage?

Q-function 21

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This shows the

relationship between

F.M and Probability

of outage.

What if we have a higher outage probability i.e. 0.9% ?

Is the Fading margin, going to be high or low?

Next Lecture 24

Statistical Description of the Wireless Channel

Two-Path Model

Small-scale fading