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.
b. non persistent
23. Draw the frame structure of movable boundary frame polling system 24. Difference between ALOHA and slotted ALOHA.
25. Explain about space diversity.
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 diversity? Explain the time diversity using rake receiver and traditional modems & equalizers. (16)
4. Explain about space and frequency diversity. ` (16)
5. Explain about random access method? (16)
6. Explain about integration of voice traffic. (16)
WIRELESS NETWORK PLANNING AND OPERATION
PART –A (2 Marks)
1. Name any three advantages of an infrastructure topology over an adhoc network topology.
2. Compare single hop and multihop networks topologies.
3. Name the five different cell types in the cellular hierarchy and compare them in terms of coverage area antenna site.
4. Why is hexagonal cell shape preferred over square or triangular cell shape to represent the cellular architecture?
5. Name five architecture methods that are used to increase the capacity of an analog cellular system without increasing the number of antenna sites. 6. Explain the following:
a. Cell splitting
b. Cell sectoring
c. Cell partitioning
7. Explain how smart antennas can improve the capacity of cellular network. 8. What are channel allocation techniques?
9. Explain the terms FCA, DCA, HCA.
10. Compare FCA and DCA.
11. Define channel borrowing technique and give its types.
12. Define mobility management.
13. Name the two important issues in mobility management.
14. What is location management? What are the three components? 15. Name three paging mechanisms.
16. Explain about paging.
17. Explain three traditional handoff techniques?
18. Difference between mobile controlled and mobile assisted hand off? 19. Difference between centralized and distributed power control. 20. What are the two steps in hand off?
21. What are the privacy and authentication requirements of wireless networks? 22. How are public key and secret key algorithms different?
23. Explain the importance of key sizes in the security of an encryption algorithm? 24. What is challenge response scheme?
25. What are the parts in location management?
1. Explain the two fundamental types topologies...