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Digital Communication - Jun 19
Electronics Engineering (Semester 5)
Total marks: 80
Total time: 3 Hours
INSTRUCTIONS
(1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Draw neat diagrams wherever necessary.
1. Attempt any four
i)Unipolar RZ
ii) Unipolar NRZ
iii) Bipolar NRZ
iv) AMI RZ
v) Manchester
S | S1 | S2 | S3 | S4 | S5 | S6 | S7 | S8 |
---|---|---|---|---|---|---|---|---|
P | 1/4 | 1/8 | 1/16 | 1/16 | 1/16 | 1/4 | 1/16 | 1/8 |
Construct Shannon-Fano code. Also find the source entropy, information rate and code efficiency.
Determine the code words for the messages:
(i) 0011
(ii) 0100 and
(iii) 0110
Also show how error is detected when $2^{\text { nd }}$ bit is detected erroneously for data word 0011$?$ \lt/div\gt \ltspan class='paper-ques-marks'\gt(10 marks)\lt/span\gt \ltspan class='paper-page-id'\gt00\lt/span\gt \lt/div\gt \ltDIV class='paper-question'\gt \ltDIV class='paper-ques-desc'\gt \ltb\gt5.b.\lt/b\gt Compare BASK, BPSK and BFSK, based on following parameters: Bandwidth, detection method, noise immunity, transmission rate and signal space representation. \lt/div\gt \ltspan class='paper-ques-marks'\gt(5 marks)\lt/span\gt \ltspan class='paper-page-id'\gt00\lt/span\gt \lt/div\gt \ltDIV class='paper-question'\gt \ltDIV class='paper-ques-desc'\gt \ltb\gt5.c.\lt/b\gt Compare OQPSK with MSK. \lt/div\gt \ltspan class='paper-ques-marks'\gt(5 marks)\lt/span\gt \ltspan class='paper-page-id'\gt00\lt/span\gt \lt/div\gt \ltDIV class='paper-question'\gt \ltDIV class='paper-ques-desc'\gt \ltb\gt6.a.\lt/b\gt Write short notes on : i) optical communication system ii) Satellite Communication System \lt/div\gt \ltspan class='paper-ques-marks'\gt(10 marks)\lt/span\gt \ltspan class='paper-page-id'\gt00\lt/span\gt \lt/div\gt \ltDIV class='paper-question'\gt \ltDIV class='paper-ques-desc'\gt \ltb\gt6.b.\lt/b\gt Sketch the signal constellation diagram $(\mathrm{d}=2 \mathrm{a})$ for $16-\mathrm{QAM}$ system and Derive the expression for its Symbol energy, Es. Prove that the noise immunity of $16-$ QAM is better than that of 16 -PSK system.