SRM University 2007 B.Tech Electronics and Communications Engineering BANK : Communication Engineering - Question Paper

7. Why class-B power amplifier is used in low power level AM transmitter?
8. What is TRF receiver?
9. Write the advantages of TRF receiver.
10. Write the limitations of TRF receiver.
11. Define Selectivity.
12. Define Fidelity.
13. Define Super-heterodyne principle.
14. Define Sensitivity.
15. What is the function of mixer in super-heterodyne receiver?
16. What is the fixed value of IF in AM receiver?
17. Write the advantages of using Super-heterodyne receiver.
18. What is meant by Synchronous detection?
19. Draw the Envelope detector circuit diagram.
20. What is the effect of Phase fault in Synchronous detection of DSB-SC & SSB signals?
21. What are the kinds of AM receiver?
22. What is meant by low power level AM transmitter?
23. What is meant by high power level AM transmitter?
24. What is the difference ranging from TRF & Super-heterodyne receiver?
25. Define Multiplexing.
26. Define FDM.
27. Give the applications of FDM.

PART B
1. Explain the detection of amplitude modulated signal using envelope detector circuit.
2. Explain synchronous detection of DSB-SC wave & explain about the effect of phase & frequency fault.
3. Explain synchronization techniques for the detection of SSB-SC.
4. Explain the low level AM transmitter with neat diagram .
5. Explain the high level AM transmitter with neat diagram.
6. Explain the TRF receiver with neat diagram.
7. Explain the Super-heterodyne receiver with neat diagram.
8. Explain frequency division multiplexing in detail.

UNIT 3
PART A
1. Define FM and PM.
2. What is the function of discriminator?
3. What is the difference ranging from FM and AM receivers.
4. What are the drawbacks of slope detector
5. How does Ratio detector differ from foster seely discriminator?
6. What is the use of limiter in FM receivers?
7. What is the value of IF in AM and FM receiver?
8. Define Super heterodyne principle.
9. What is the function of Pre-emphasis in FM transmitter and De-emphasis in FM receiver?
10. Write the relationship ranging from FM and PM.
11. Write the difference ranging from narrow band FM and wide band FM.
12. Define frequency sensitivity.
13. Draw the phasor diagram of narrow band FM.
14. Define figure of merit.
15. Define signal to noise ratio in FM.
16. Define phase deviation.
17. Show that a LPF can be used as a discriminator.
18. An FM signal, modulated to a depth of 8,generates a bandwidth of 180KHz.calculate the frequency deviation.

Earning:   Approval pending.