(R15A0409) ANALOG COMMUNICATIONS Course Objectives: Objective of the course is to: • Emphasize on the study of principles of communication theory
ANALOG COMMUNICATIONS Lecture Notes B TECH (III YEAR – I SEM) (2019-20) Prepared by: Ms P SWETHA, Assistant Professor(Unit 1 2)
LECTURE NOTES ON ANALOG COMMUNICATIONS (AEC005) B Tech-ECE-IV semester Dr P Munusamy, Professor, ECE Ms G Ajitha, Assistant Professor, ECE
In analog communication systems, the message signals are transmitted in analog form itself AM, FM and PM are common analog modulation schemes which uses
Lecture Notes On Analogue Communication Techniques (Module 1 2) Topics Covered: 1 Spectral Analysis of Signals 2 Amplitude Modulation Techniques
Modulation – Comparison of various Analog Communication System (AM – FM – PM) In this case it is interesting to note that the equivocation,
3 Modern Digital and Analog Communication Systems, by B P Lathi, Oxford to note from this section is that noise is inevitable
analog modulations it is often important to discuss the signal bandwidth and this will be denoted W Note that this W could correspond to either relative or
frequency domain, basic analog communication techniques like modulation theory 5 http://manajntu com/jntu-analog-communication-ac-study-material-notes/
Analog Communication 10EC53 SJBIT/Dept of ECE Page 11 Modulating wave AM wave Figure 2 1: message, carrier and amplitude modulated signal Note:
![[PDF] ece-v-analog-communication-10ec53-notespdf - Atria e-Learning [PDF] ece-v-analog-communication-10ec53-notespdf - Atria e-Learning](https://pdfprof.com/EN_PDFV2/Docs/PDF_1/8196_1ece_v_analog_communication_10ec53_notes.pdf.jpg)
8196_1ece_v_analog_communication_10ec53_notes.pdf
Analog Communication 10EC53
SJBIT/Dept of ECE Page 1
SYLLABUS
ANALOG COMMUNICATION
Subject Code: 10EC53
IA Marks: 25 No. of Lecture Hrs/Week: 04 Exam Hours: 03 Total no. of Lecture Hrs: 52 Exam Marks: 100
PART A
UNIT - 1
RANDOM PROCESS: Random variables: Several random variables. Statistical averages: Function of Random variables, moments, Mean, Correlation and Covariance function: Principles of autocorrelation function, cross correlation functions. Central limit theorem, Properties of Gaussian process. 7 Hours
UNIT - 2
AMPLITUDE MODULATION: Introduction, AM: Time-Domain description, Frequency Domain description. Generation of AM wave: square law modulator, switching modulator. Detection of AM waves: square law detector, envelop detector. Double side band suppressed carrier modulation (DSBSC): Time-Domain description,
Frequency-Domain representation, Generation of DSBSC waves: balanced modulator, ring modulator. Coherent detection of DSBSC modulated waves. Costas loop. 7 Hours
UNIT - 3
SINGLE SIDE-BAND MODULATION (SSB): Quadrature carrier multiplexing, Hilbert transform, properties of Hilbert transform, Pre envelope, Canonical representation of band pass signals, Single side-band modulation, Frequency-Domain description of SSB wave, Time-Domain description. Phase discrimination method for generating an SSB modulated wave, Time-Domain description. Phase discrimination method for generating an SSB modulated wave. Demodulation of SSB waves. 6 Hours
UNIT - 4
VESTIGIAL SIDE-BAND MODULATION (VSB): Frequency Domain description, Generation of VSB modulated wave, Time - Domain description, Envelop detection of VSB wave plus carrier, Comparison of amplitude modulation techniques, Frequency
translation, Frequency division multiplexing, Application: Radio broadcasting, AM radio.
6 Hours
PART B
UNIT - 5
ANGLE MODULATION (FM)-I: Basic definitions, FM, narrow band FM,wide band FM, transmission bandwidth of FM waves, generation of FM waves: indirect FM and
direct FM. 6 Hours
UNIT - 6
ANGLE MODULATION (FM)-II: Demodulation of FM waves, FM stereo multiplexing, Phase-locked loop, Nonlinear model of the phase locked loop, Linear
Analog Communication 10EC53
SJBIT/Dept of ECE Page 2
model of the phase locked loop, Nonlinear effects in FM systems.
7 Hours
UNIT - 7
NOISE: Introduction, shot noise, thermal noise, white noise, Noise equivalent bandwidth, Narrow bandwidth, Noise Figure, Equivalent noise temperature, cascade connection of two-port networks. 6 Hours
UNIT - 8
NOISE IN CONTINUOUS WAVE MODULATION SYSTEMS:
Introduction, Receiver model, Noise in DSB-SC receivers, Noise in SSB receivers, Noise in AM receivers, Threshold effect, Noise in FM receivers, FM threshold effect, Pre-emphasis and De-emphasis in FM. 7 Hours
TEXT BOOKS:
1. Communication Systems, Simon Haykins, 5th Edition, John Willey, India Pvt. Ltd,
2009.
2. An Introduction to Analog and Digital Communication, Simon Haykins, John Wiley
India Pvt. Ltd., 2008
REFERENCE BOOKS:
1. Modern digital and analog Communication systems B. P. Lathi, Oxford University
Press., 4th ed, 2010,
2. Communication Systems, Harold P.E, Stern Samy and A Mahmond, Pearson Edn,
2004.
3. Communication Systems: Singh and Sapre: Analog and digital TMH 2nd , Ed 2007.
Analog Communication 10EC53
SJBIT/Dept of ECE Page 3
INDEX SHEET
SL.NO TOPIC PAGE NO.
I UNIT 1 RANDOM PROCESS 4-8
II UNIT 2 AMPLITUDE MODULATION 9-24
III UNIT 3 SINGLE SIDE-BAND
MODULATION (SSB) 25-39
IV UNIT 4 VESTIGIAL SIDE-BAND
MODULATION 40-46
V UNIT 5 ANGLE MODULATION (FM)-I 47-56
VI UNIT 6 ANGLE MODULATION (FM)-II 57-62
VII UNIT 7 NOISE: 63-67
VIII
UNIT 8 NOISE IN CONTINUOUS
WAVE MODULATION SYSTEMS:
68-73
Analog Communication 10EC53
SJBIT/Dept of ECE Page 4
UNIT 1
RANDOM PROCESS: Random variables: Several random variables. Statistical averages: Function of Random variables, moments, Mean, Correlation and Covariance function: Principles of autocorrelation function, cross correlation functions. Central limit theorem, Properties of Gaussian process. 7 Hrs
TEXT BOOKS:
1. Communication Systems, Simon Haykins, 5th Edition, John Willey, India Pvt. Ltd,
2009.
2. An Introduction to Analog and Digital Communication, Simon Haykins, John
Wiley India Pvt. Ltd., 2008
REFERENCE BOOKS:
1. Modern digital and analog Communication systems B. P. Lathi, Oxford University
Press., 4th ed, 2010
2. Communication Systems, Harold P.E, Stern Samy and A Mahmond, Pearson Edn,
2004.
3. Communication Systems: Singh and Sapre: Analog and digital TMH 2nd , Ed 2007.
Analog Communication 10EC53
SJBIT/Dept of ECE Page 5
1.1. Random Process
A random process is a signal that takes on values, which are determined (at least in part) by chance. A sinusoid with amplitude that is given by a random variable is an example of a random process. A random process cannot be predicted precisely. However, a deterministic signal is completely predictable. An ergodic process is one in which time averages may be used to replace ensemble averages. As signals are often functions of time in signal processing applications, egodicity is a useful property. An example of an ensemble average is the mean win at the blackjack tables across a whole casino, in one day. A similar time average could be the mean win at a particular blackjack table over every day for a month, for example. If these averages were approximately the same, then the process of blackjack winning would appear to be ergodic. Ergodicity can be difficult to prove or demonstrate, hence it is often simply assumed.
1.2. Probabilistic Description of a Random Process
Although random processes are governed by chance, more typical values and trends in the signal value can be described. A probability density function can be used to describe the typical intensities of the random signal (over all time). An autocorrelation function describes how similar the signal values are expected to be at two successive time instances. It can
Probability Theory:
Statistics is branch of mathematics that deals with the collection of data. It also concerns with what can be learned from data. Extension of statistical theory is Probability Theory. Probability deals with the result of an experiment whose actual outcome is not known. It also deals with averages of mass phenomenon. The experiment in which the Outcome cannot be predicted with certainty is called Random Experiment. These experiments can also be referred to as a probabilistic experiment in which more than one thing can happen. Eg: Tossing of a coin, throwing of a dice. Deterministic Model and Stochastic Model or Random Mathematical Mode can be used to describe a physical phenomenon. In Deterministic Model there is no uncertainty about its time dependent behavior. A sample point corresponds to the aggregate of all possible outcomes. Sample space or ensemble composed of functions of time-Random Process or stochastic Process.
Types of Random Variable(RV):
1. Discrete Random Variable: An RV that can take on only a finite or countably infinite
set of outcomes.
2. Continuous Random Variable: An RV that can take on any value along a continuum
W H O \