Important Questions in Communication Engineering EC2311  EC 2311 subject for NOV/DEC 2011 ANNA UNIVERSITY EXAMINATIONS FOR III YEAR EEE Students

EC2311 - Communication Engineering

UNIT I
1.      Describe the operation of frequency division multiplexing.
2.      Derive an expression for amplitude modulated wave and its power relations. Also give time and frequency domain representation.
3.      Explain super heterodyne receiver with suitable block diagram

UNIT II
1.      Describe pulse code modulation scheme and draw the wave forms.
2.      Explain the working of QAM modulator and detector with the signal constellation diagram
3.      Draw the block diagram of BPSK transmitter and receiver. Explain the same digital modulation scheme with appropriate constellation diagram.
4.      Draw the block diagram of a TDM system and explain where TDM is applied

UNIT III

1.      The parity check matrix of a(7,4) linear block code if given as
1  1 0 0 1 0 0
[H]=     0 1 1 0 0 1 0
0 0 1 1 0 0 1. Find the generator matrix and all the code vectors.

2.      For the convolutional encoder, determine the Code rate, Dimension of the code, output sequence for the message sequence m=1 1 1 1 0 0 1

3. A binary symmetric channel is shown in the figure.

Find the channel matrix, P(y0) and P(y1) if P(x0)=0.3 and P(x1)=0.7
4        Five source messages are probable to appear as m1=0.4, m2=0.15, m3=0.15, m4=0.15, m5=0.15 . Find the coding efficiency for 1. Shannon Fano coding, 2. Huffmann Coding.
UNIT IV

1.      Explain with block diagram of  Transmitter and Receiver using FDMA Concept.
2.      Compare multiple access techniques FDMA, TDMA, CDMA.
3.      Explain the model of sped spectrum digital communication system with a neat block diagram.

UNIT V

1.       Distinguish among single mode step index, multimode step index and multimode graded index optical fibers.
2.       Give short notes on the following :
(a)   Satellite subsystems (b) Power line carrier systems.
3.       What are the benefits of satellite communication systems? How is the position/location of satellite tracked from the earth station? Derive the satellite link equations and component on it
4.       Briefly describe the functional characteristics of an up-link, a transponder and a down-link model for a satellite system.

Important Questions in Communication Engineering EC2311 EC 2311 subject for NOV/DEC 2011 ANNA UNIVERSITY EXAMINATIONS FOR III YEAR EEE Students Reviewed by Rejin Paul on 7:00 AM Rating: 5