Chhattisgarh Swami Vivekanand Technical University, Bhilai
Semester : V Branch: Electronics & Telecommunication
Subject: Communication System – I
Unit – I
Fourier Series, Normalised power in a Fourier expansion, Power Spectral Density, Fourier
transform, Perseval’s Theorem, Power & Cross co-relation, Auto co-relation, Bandlimiting of waveforms.
Unit – II
Linear Modulation: Amplitude Modulation:
Amplitude Modulation, Generation of AM waves, Demodulation of
AM waves, Suppressed carrier modulation, DSB-SC modulation, Generation of DSB-SC signals, Detection of
DSB-SC signals, Single-tone modulated DSB-SC, Quadrature AM, SSB-SC modulation, Generation of SSB-SC
signals, Detection of SSB-SC signals, VSB, Comparison of various AM systems.
Unit – III
Exponential Modulation: Phase & Frequency Modulation:
Mathematical representation of FM & PM signals,
Single tone FM, Multitone FM, Transmission BW of FM waves, WBFM and NBFM, Generation of FM waves,
Demodulation of FM waves, Interference, De-emphasis and Pre-emphasis filtering.
Unit – IV
Radio Transmitters & Receivers:
General block diagram of AM, FM and PM transmitters, Block diagram of high
level and low level AM Transmitter
High level transistor collector modulator, Low level transistor modulator,
Balanced modulator for SSB generation. Reactance modulator for FM generation, Direct FM transmitter, Indirect
(Armstrong) FM transmitter, Block diagram of Stereophonic FM transmitter
TRF receivers – sensitivity & Selectivity, Superhetrodyne receivers – image frequency & its rejection, SSB
receivers. Block diagram of FM receivers.
(This unit should be covered in a Block diagrammatic approach rather
than covering the detail of the circuits.)
Unit – V
Noise in CW Modulation: V
arious noise sources, Noise calculations for – single noise sources, multiple noise
sources, cascade and cascade amplifiers. Noise figure and its measurement, Noise temperature, Equivalent input
noise resistance, noise Bandwidth, noise measurement on line and channel. Band – pass noise representation,
noise figure calculation for various modulation systems (DSB-AM, DSB-SC, SSB and FM), Effects of transmitter
noise. Noise in Angle Modulated systems: Noise in FM systems, Threshold in FM, Threshold improvement through
De-emphasis, Noise in phase modulation.
Name of Text Books:
1. Principles of Communication Systems
by Taub and schilling ; Tata McGraw Hill
A Text Book of Analog & Digital Communication – P. Chakrabarti, Dhanpat Rai & Co.
Name of Reference Books:
Electronic Communication systems by George F Kennedy : Tata McGraw Hill
Communication Systems Engineering, Proakis, 2nd
Ed., Pearson Education
Electronic Communications, Roddy & Collen, 4th
Analog and Digital Communication systems, Martin S. Roden, 5th
Ed., Shroff Publishers & Distributors