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
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