UNIT I
PHYSICAL AND WIRELESS MAC LAYER ALTERNATIVES PART – A (2 Marks)
1. Name five design consideration in selecting a modulation scheme for a wireless networks.
2. Why is out of band of radiation an important issue in designing modulation scheme?
3. Why is PPM used with IR communication instead of PAM?
4. Name four space diversity techniques.
5. What are the advantages of high efficiency voice band modems?
6. Draw the structure of DFE.
7. Define ACI.
8. What are the types of diversity?
9. Draw the structure of adaptive MLSE receiver.
10. Draw the structure of linear transversal equalizer.
11. In an OFDM modem with 48 channels, each channel uses 16 QAM modulations. if the overall transmission rate is 10 Mbps. What is the symbol transmission rate per channel?
12. What are the sectored antennas? How they are useful in combating multipath?
13. What are the popular access schemes for data networks? Classify them.
14. What is the difference between the access technique of IEEE802.3 and IEEE802.11?
15. What is the difference between performance evaluations of voice oriented fixed assignment and data oriented random access?
16. What is the difficulty of implementing CSMA? CD in a wireless environment?
17. Explain about CSMA.
18. Explain about hidden terminal problem.
19. Explain about capture effect.
20. Write down the formula for Nidle.
21. Sketch the operation of CSMA protocol.
22. Define:
a. persistent
b. non persistent
c. 1-persistent
d. p-persistent
23. Draw the frame structure of movable boundary frame polling system
24. Difference between ALOHA and slotted ALOHA.
25. Explain about space diversity.
PART B
1. Explain the following: (16)
a. bandwidth efficiency
b. power efficiency
c. out of band of radiation
d. UWB pulse transmission
2. What is OFDM? Explain about multicarrier, multisymbol and multirate OFDM. (16)
3. Why we are going for