Introduction and History of Telecommunication

Introduction and History to communications by Dr. Mussaab I. Niass Signal analysis, Fourier transforms, Power spectrum, Principles of
modulation, amplitude, frequency, phase, composite and pulse
modulation, voice digitization, pulse code modulation (PCM), delta
modulation, linear predictive coding (LPC). Comparison of analog
and digital transmission. Time, frequency and code division
multiplexing, random signals and noise. Transmission systems for
cable, radio, satellite and optical links

1. مسِب

ﷲ

نمحرلا

ميحرلا
International University of Africa (I.U.A)
Faculty of Engineering
Electronic & Electrical Department
Communication -1
تﻻﺎﺼﺗﻹإ- 1
Semester -7
Lecture-1/ Introduction and History
Instructor name: Mussaab I. Niass
2023
1

2. 
Course work:
(40 Deg.)

Labs (20)

Exam-1 and 2 (20)

Final Exam: (Electronic Exam) //
paper based

60 Degree // Hint: Supplementary –Second round exam (100 Deg.)

Office: 2
nd
floor, administration building, office # …, Faculty of
Engineering, I.U.A, Khartoum, Sudan

Instructor name:
Mussaab I. Niass
(BSC. I.U.A, 2010, 2
nd
Batch)(
Telecommunication Eng., MSC. SUST. , 2015, Ph.D., ZZU, China, 2022).

Email: [email protected],( Sorry no Telephones!!).
2

3. Course Content:

Signalanalysis,Fouriertransforms,Powerspectrum,Principlesof
modulation,amplitude,frequency,phase,compositeandpulse
modulation,voicedigitization,pulsecodemodulation(PCM),delta
modulation,linearpredictivecoding(LPC).Comparisonofanalog
anddigitaltransmission.Time,frequencyandcodedivision
multiplexing,randomsignalsandnoise.Transmissionsystemsfor
cable,radio,satelliteandopticallinks.
3

4. Course objectives

The main objective of this course is to understand and implement
the basic analog communication techniques/ circuits with the help
of theoretical and practical problem solving.

5. Course Outcomes

Attheendofthecourse,studentisexpectedto
understand:

Basicworkingofcommunicationsystem.

AnalogModulationTechniquesandtheircomparative
analysisandapplicationssuitability.

ProcessofModulationandDemodulation.

AnalogtodigitalconversionandDigitaldatatransmission.

MultiplexingTechniques.

Basicworkingprinciplesofexistingandadvanced
communicationtechnologies.

6. 6
References:
1.
B.PLathi,ModernDigitalandAnalogCommunications
Systems,3
rd
Edition,1998.
2.
JohnG.Proakis,CommunicationSystemsEngineering,2
nd
2001.
3.
SimonHaykin,CommunicationSystems,4thEdition,2000.
4.
DonaldL.Schilling,HerbertTaub,Principlesof
CommunicationSystems,2
nd
Edition.
5.
LouisE.Frenzel,“PrinciplesofElectronicCommunication
Systems”,McGraw-Hill,3rdEdition,2007.

7. Chapter 1 Introduction
“To understand a science it is necessary to know its history”
-Auguste Comte (1798-1857)
“To understand a science it is necessary to know its history”
-Auguste Comte (1798-1857)

8. Methods of communication:
1.Face to face
2.Signals
3.Written word (letters)
4.Electrical innovations:
Telegraph
Telephone
Radio
Television
Internet (computer)

9. 9
1.1 Historical Background

Telegraph

1844, Samuel Morse,

“What hath God wrought” transmitted by Morse’s electric telegraph

Washington D.C ~ Baltimore, Maryland

Morse code : variable-length code (a dot, a dash, a letter space, a word
space)

10. History

Radio

1864, James Clerk Maxwell

Formulated the electromagnetic theory of light

Predicted the existence of radio waves

1887, Heinrich Hertz

The existence of radio waves was confirmed experimentally

1894, Oliver Lodge

Demo : wireless communication over a relatively short distance (150 yards)
10

11. 11
History

1901, Guglielmo Marconi

Demo : wireless communication over a long distance (1700 miles, 2735.885
km)

1906, Reginald Fessenden

Conducting the first radio broadcast

1918, Edwin H. Armstrong

Invented the super-heterodyne radio receiver

1933, Edwin H. Armstrong

Demonstrated another modulation scheme ( Frequency modulation)

12. History

Telephone

1875, Alexander Graham Bell

Invented the telephone

1897, A. B. Strowger

Devised the automatic step-by-step switch
12

13. 13

Electronics

1904, John Abbrose Eleming

Invented the vacuum-tube diode

1906, Lee de Forest

Invented the vacuum-tube triode

1948, Walter H. Brattain, William Shockley (Bell Lab.)

Invented the transistor

1958, Robert Noyce

The first silicon integrated circuit (IC) produce

Television

1928, Philo T. Farnsworth

First all-electronic television system

1929, Vladimir K. Zworykin

all-electronic television system

1939, BBC

Broadcasting television service on a commercial basis

14. 14
1.2 Applications

Broadcasting

Which involves the use of a single powerful transmitter and numerous
receivers that are relatively inexpensive to build

point-to-point communications

In which the communication process takes place over a link between a
single transmitter and a single receiver.

15. Figure 1: A general model of all communication systems.

16. 16

Radio

Broadcasting

AM and FM radio
•
The voices are transmitted from broadcasting stations that operate in our
neighborhood

Television
•
Transmits visual images and voice

17. 17

18. 18

19. Types of Communication Systems

Electroniccommunicationsare
classifiedaccordingtowhethertheyare
1.
One-way(simplex)ortwo-way(full
duplexorhalfduplex)transmissions
2.
Analogordigitalsignals.

20. Simplex

Thesimplestmethodofelectronic
communicationisreferredtoassimplex.

Thistypeofcommunicationisone-way.
Examplesare:

Radio

TVbroadcasting

Beeper(personalreceiver)

21. FullDuplex

Mostelectroniccommunicationistwo-way
andisreferredtoasduplex.

Whenpeoplecantalkandlisten
simultaneously,itiscalledfullduplex.The
telephoneisanexampleofthistypeof
communication.

22. Half Duplex

Theformoftwo-waycommunicationin
whichonlyonepartytransmitsatatime
isknownashalfduplex.Examplesare:

Police,military,etc.radiotransmissions

Citizenband(CB)

Familyradio

Amateurradio

23. 23
Point-to-point communication
Satellite communication
Built around a satellite in geostationary orbit, relies on
line-of-sight radio propagation for the operation of an
uplink and a downlink

24. 24
1.3 Primary Resources and Operational Requirements

The systems are designed to provide for the efficient utilization of
the two primary communication resources:

Transmitted power

Defined as: The average power of the transmitted signal

Channel bandwidth

Defined as: The width of the passband of the channel

Classify communication channel

Power-limited channel
•
Wireless channels
•
Satellite channels
•
Deep-space links

Band-limited channel
•
Telephone channels
•
Television channels

25. 25

The design of a communication system boils down to a tradeoff
between signal-to-noise ratio and channel bandwidth

Improve system performance method

Signal-to-noise ratio is increased to accommodate a limitation imposed on
channel bandwidth

Channel bandwidth is increased to accommodate a limitation imposed on
signal-to-noise ratio.

26. 26
1.4 Understanding Theories of Communication Systems

Modulation Theory

Sinusoidal carrier wave

Whose amplitude, phase, or frequency is the parameter chosen for
modification by the information-bearing signal

Periodic sequence of pulses

Whose amplitude, width, or position is the parameter chosen for
modification by the information-bearing signal

The issues in modulation theory:

Time-domain description of the modulation signal.

Frequency-domain description of the modulated signal

Detection of the original information-bearing signal and evaluation of the
effect of noise on the receiver.

27. 27

Fourier Analysis

Fourier analysis provides the mathematical basis for evaluating the
following issues

Frequency-domain description of a modulated signal, including its
transmission bandwidth

Transmission of a signal through a linear system exemplified by a
communication channel or filter

Correlation between a pair of signals

Detection Theory

Signal-detection problem

The presence of noise

Factors such as the unknown phase-shift introduced into the carrier wave
due to transmission of the sinusoidally modulated signal over the channel

28. 28
1.5 Concluding Remarks

Communication systems encompass many and highly diverse applications

Radios, television, wireless communications, satellite communications, deep-
space communications, telephony, data networks, Internet, and quite a few
others

The study of communication systems is a dynamic discipline, continually
evolving by exploiting new technological innovations in other disciplines
and responding to new social needs.

Last but by no means least, communication systems touch out daily lives
both at home and in the workplace, and our lives would be much poorer
without the wide availability of communication devices that we take for
granted.

29. Thank you ….
29