B.E-B.E Electronics and Tele-Communication Engineering Digital Communication(Sathyabama University, Chennai, Tamil Nadu-2010)
Friday, 23 August 2013 03:23Duraimani
(Established under section 3 of UGC Act,1956)
Course & Branch :B.E - ETCE
Title of the Paper :Digital Communication Max. Marks :80
Sub. Code :525506/6C0098 Time : 3 Hours
Date :28/04/2010 Session :AN
PART - A (10 x 2 = 20)
Answer ALL the Questions
1. State Bandpass Sampling theorem.
2. What is the condition for zero inter symbol interference?
3. Draw the waveform for the binary data sequence 10110 modulated under
(a) FSK (b) PSK
4. What are the advantages and disadvantages of DPSK?
5. What is necessity of synchronization?
6. What is the difference between open loop and closed transmitter synchronization?
7. List any two applications of spread spectrum modulation.
8. What do you mean by Jamming?
9. Define plain text and cipher text.
10. What are the limitations of public key encryption system?
PART – B (5 x 12 = 60)
Answer All the Questions
11. Explain the process of quantization and also derive expressions for the quantization noise and SNR in a PCM system using a uniform quantizer.
(or)
12. (a) Define ISI.
(b) Discuss in detail about Adaptive equalization.
13. Draw the block diagram of MSK transmitter and Receiver and explain the function of each block.
(or)
14. Derive an expression for the probability of symbol error for the BPSK transmission.
15. Describe the symbol synchronization in detail.
(or)
16. Explain in detail Frequency Synchronization.
17. Draw the block diagram of Frequency hopped spread spectrum and explain.
(or)
18. Explain the direct sequence spread spectrum modulation techniques with suitable diagram.
19. Short notes on:
(a) Ideal secrecy.
(b) Practical security.
(or)
20. Explain in detail public key Encryption Section.
| Earning: ₹ 3.01/- |
