/
Chapter 1. Introduction Chapter 1. Introduction

Chapter 1. Introduction - PowerPoint Presentation

test
test . @test
Follow
381 views
Uploaded On 2016-11-21

Chapter 1. Introduction - PPT Presentation

Husheng Li The University of Tennessee Course Contents Basics of communications Signals and noise Amplitude modulation Phase and frequency modulations Pulse modulation Analog communication system ID: 491465

coding modulation communication history modulation coding history communication noise communications signal information signals experiment modulations source system analog transmission

Share:

Link:

Embed:

Download Presentation from below link

Download Presentation The PPT/PDF document "Chapter 1. Introduction" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.


Presentation Transcript

Slide1

Chapter 1. Introduction

Husheng Li

The University of TennesseeSlide2

Course Contents

Basics of communications

Signals and noise

Amplitude modulation

Phase and frequency modulations

Pulse modulation

Analog communication systemSlide3

Textbook

Communication Systems: An Introduction to Signals and Noise in Electrical Communication, by A. B. Carlson and P. B.

Crilly

, McGraw Hill, 5

th

edition, 2008Slide4

Logistics

Homework: 20% (4 problems every Friday; turn in your homework in two weeks)

Midterm and final exams: 40%

Quiz: 15% (will be 5 quizzes)

Experiments: 25%Slide5

Office hour and TA

2:15 --- 3:15pm, MWF, MK644

TA:

Jingchao

Bao, jbao2@utk.edu

Course website: go to my personal website

http://

web.eecs.utk.edu

/~

husheng

/Slide6

Experiments

Experiment 1:

Matlab

simulation for amplitude modulations.

Experiment 2:

Matlab simulation for frequency and phase modulations.Experiment 3: USRP hardware board experimentSlide7

Concepts

A communication system conveys information from its source to a destination some distance away.

Some concepts: Information, analog, digital, transducerSlide8

Elements of Communication Systems

The transmitter involves modulation and coding.

The transmission channel is the medium for communications, which could be wireless, optical or even sound.

The receiver carries out demodulation and decodingSlide9

Negative Factors in Communications

Distortion: Waveform perturbation caused by imperfect response of the system to the desired signal itself.

Interference: Contamination by extraneous signals

Noise: Random and unpredictable electrical signals.Slide10

Fundamental Limitations

Communications are limited by bandwidth and noise.

Bandwidth: the width of frequency band used for the communications.

Noise: The signal-to-noise ratio (SNR; S/N) is important.

When the noise is Gaussian, the channel capacity is given bySlide11

Modulation

Modulation involves two waveforms: a modulating signal and a carrier wave.

Modulating

signal

Amplitude

Modulation

Pulse train

With AMSlide12

Coding

Coding is a symbol processing operation for improved communication when the information is digital or can be approximated in the form of discrete symbols (actually there is also analog coding).

Source coding converts source information into a series of bits.

Channel coding: add redundancy to improve the robustness of transmission.Slide13

EM Transmission

there are several effects that enable light as well as electromagnetic (EM) waves to propagate around obstructions or beyond the earth’s horizon Slide14

Multipath and Fading

In wireless communications, the signal could be received by the receiver after reflections.

The superposition of signals from different paths could strengthen or weaken each other.Slide15

Emerging Developments

Circuit / packet switching

Multiple access: TDMA, CDMA, OFDMA.

Ultra-wideband (UWB)

Computer Networks:

WiFi (IEEE 802.11) and WiMAX

(IEEE 802.16)

Software defined radioSlide16

Some History (1)Slide17

Some History (2)Slide18

Some History (3)Slide19

Some History (4)Slide20

Some History (5)Slide21

Some History (6)Slide22

Assignment

Read chapter 1