SRM University 2007 B.Tech Electronics and Communications Engineering BANK : EC200 ANALOG COMMUNICATION - Question Paper

DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING
SRM INSTRUTE OF SCIENCE & TECHNOLOGY
EC200 ANALOG COMMUNICATION

ques. BANK
UNIT – I (LINEAR MODULATION)
PART - A
1. Define Modulation.
2. Define Amplitude Modulation.
3. Define Frequency Modulation.
4. Define Phase Modulation.
5. Write the expression for AM.
6. Draw the spectrum of AM signal.
7. What is Modulation index in AM?
8. Define Percentage of Modulation.
9. What is Envelope detection?
10. State Merits of Demerits of AM.
11. A carrier wave of frequency 10M Hz & peak value 10V is amplitude modulated by a 5K Hz sine wave of amplitude 6V. Determine the modulation index and draw the amplitude spectrum.
12. What are the 2 kinds of distortions in Envelope detector?
13. What is quadrature null effect?
14. What are the advantages of Single Side Band modulation?
15. What is VSB Transmission?
16. Give the advantages of balanced modulator.
17. Write short note on the distortion produced in square legal regulations detector.
18. Write about the VSB modulator.
19. Write about VSB demodulator.
20. What is the power saving in DSB SC and SSB – SC AM?
21. Give the 2 methods of generating DSB AM?
22. What are the applications of SSB-SC?
23. Draw the diagram of balanced modulator for generating AM with carrier.
24. What amount of useful power is transmitted using amplitude modulation?
25. What is the advantage of suppressing carrier during transmission?
26. What are the various degrees of modulation in AM?
27. Draw the phasor representation of AM wave.
28. Give the expression for the relationship ranging from the side band power and modulation index in DSB AM?
29. Give the merits and demerits of phase shift method for generation of SSB?
30. Give the Merits and demerits of replaced phase shift for SSB generation?


PART – B
1. Derive an expression for AM wave.
2. Prove that Pt = Pc (1+ ) in AM.
3. Explain the working of Envelope detector.
4. Write any 1 method of AM generation.
5. Explain the DSB wave generation using a Balanced Modulator.
6. Explain in detail about Costas Receiver.
7. Explain the method of generation of DSB – SC waves using Ring modulator.
8. Explain the weaver’s method for the generation of SSB – SC AM.
9. Explain the phase shift method for SSB generation with its merits and demerits.
10. Explain the generation and detection of VSB AM.
11. An amplitude modulated signal represented by v (t) = 10 [ 1+0.1 Cos 2512t + 0.5 Cos 6080t] Sin (107 + 45o) elaborate the info you gather from this? Plot the spectrum of the signal.
12. A transmitter radiates nine KW when unmodulated and 10.125 KW when, modulated. compute the modulation index?. If a different sine wave corresponding to 40% modulation transmitted simultaneously, determine the total power?
13. A carrier is simultaneously modulated by 2 sine waves with modulation index of 0.3 and 0.4. obtain the total modulation index?

Earning:   Approval pending.