CELLULAR AND MOBILE COMMUNICATIONS Unit Wise Important Questions And Answers

JNTUK [CMC] CELLULAR AND MOBILE COMMUNICATIONS Unit Wise 16 Marks Important Questions And Answers

CELLULAR AND MOBILE COMMUNICATIONS Unit Wise Important Questions And Answers

UNIT-I

1. Draw the general view of telecommunication and explain the function of the each  unit?

2. Explain about NMT & NTT Systems

3. Explain the phenomena of severe fading?

4. Distinguish between the permanent splitting and dynamic splitting?

5. What are the limitations of conventional mobile systems and how are they overcome by cellular mobile systems?

6. Explain about basic cellular system.

7. Explain the direct wave path, line of sight path, out of sight path, and obstructive path?

8. What are the different types of noises in cellular frequency ranges Explain in detail?

9. Explain about the marketing of hexagonal cells?

10. Differentiate the generations in the cordless phones and cellular phones?

11. Briefly explain the evaluation of the analog and digital cellular mobile system?

12. Write notes on Digital Cellular System.

13. Explain the Trunking Efficiency.

14. Explain about the model of transmission medium.

15. Explain about planning of cellular system in detail.

UNIT-II

1. Explain the concept of frequency reuse channels.

2. Explain the frequency reuse distance in cellular radio system.

3. Explain the hand-off mechanism.

4. Explain the co channel interference reduction factor.

5. Derive the C/I for normal case in an omni directional antenna system.

6. Draw the general view of telecommunication and explain the function of the each unit?

7. What is the need of splitting and explain the cell splitting.

8. Write about maximum number of frequency channels per cell.

9. Explain the importance of  K = i2 + ij + j2

UNIT-III

1. Define co channel interference. How is it measured at the mobile unit and cell site?

2. Explain how co-channel interference is measured in real time mobile radio transceiver?

3. Explain the designing of an omnidirectional antenna system in the worst case scenario.

4. Explain the designing of the directional antenna under the practical case conditions for K=4, K=7 and K=12 with all suitable values and explaining each of them.

5. Explain the concept of lowering the antenna height to decrease the co-channel interference.

6. Write a note on power control.

7. Discuss the diversity schemes for interference reductions at both mobile unit and cell site.

8. Explain different methods to reduce the co-channel interference.

9. Write notes on channel combiners.

10. Explain the importance of demultiplexer at the receiver to reduce the non-co-channel interference.

11. Prove that for hexagonal geometry the co-channel reuse ratio is given by Q=√3N

12. What is near-end-far-end interference ratio and explain its effects?

UNIT‐IV

1. Explain ground incident angle, elevation angle, ground reflection and reflection point.

2. Write about the phase difference between the direct path and the ground reflected path.

3. Why there is a constant standard deviation along a path-loss curve.

4. Discuss the merits of point-to-point model.

5. Explain about foliage loss

6. Discuss the “Lee model” for point to point propagation.

7. Derive the relation for the maximum coverage distance in mobile environment.

8. What are the factors that effect accuracy of prediction

9. Discuss in detail about small scale multipath propagation.

10. Explain the effect of propagation of mobile signals over water.

11. Write short notes on mobile-to-mobile propagation.

UNIT-V

1.Obtain the free space path loss from the transmitting end and the receiving end of the antenna. Derive the received power in dBm. How is the measured field strength converted into the receiver power?

2. What do you understand by engineering antenna pattern? Explain the corresponding pattern.

3. Concern to the cell site antennas explain start up configuration and abnormal antenna configuration of start up systems?

4. How interference can be reduced by using the directional antennas at the cell site?

5. Explain the antenna arrangement of space diversity used at cell site.

6. Explain how umbrella pattern antennas are used as the cell site antennas.

7. Explain in detail the unique situation of the antenna with neat diagram.

8. Explain in detail about minimum separation of cell-site receiving antennas.

9. Explain the following,(a) Roof mounted antennas (b) Glass mounted antennas (c) Mobile high gain antennas.

10. Explain the following, (a) Horizontal oriented space diversity antenna (b) Vertically Oriented space diversity antenna.

UNIT-VI

1.Discuss the concept of frequency management concern to the numbering the channels and grouping into the subset.

2. What are the different techniques to utilise the frequency spectrum, give a brief explanation?

3. Explain in detail about grouping of Set-up channels.

4. Explain in detail access channels and operational techniques.

5. Explain about paging channels.

6. Write the concept of the self location scheme at the mobile unit and the autonomous registration.

7. Write about fixed channel assignment schemes in detail.

8. What are the advantages of sectorized cells?

9. Compare the omni cells and sectorized cells.

10. Explain about the Underlay-Overlay Arrangement.

11. Present the reuse partition scheme in overlaid cell system, mention the advantages associated with it.

12. What do you understand by non-fixed channel assignment? Describe the corresponding algorithms.

13. Compare the average blocking in spatially uniform and non uniform traffic distribution for FCA, BCA and FBCA.

UNIT-VII

1.Why hand off is necessary ?

2. What are the two decision making parameters of hand off explain.

3. Concept of delaying a hand off

4. What are the advantages of delayed hand off

5. Write about forced handoff

6. Write about Power difference hand off

7. What is Inter system hand off?

8. Definition of dropped call rate and consideration of dropped call rates

9. Relation among capacity, voice quality, dropped call rate

10. What is the general formula of dropped call rate? Explain?

11. Write about cell site hand off only scheme

UNIT-VIII

1.Explain in detail about GSM architecture

2. What are the services offered by GSM channels?

3. Write short notes on modes in GSM channels.

4. Explain in detail about multiple access scheme.

5. Explain the architecture of TDMA?

6. Write about the signalling format and message structure in TDMA.

7. Write short notes on,

(a) TDMA structure

(b) Frame length

(c) Frame offset

(d) Modulation timing.

8. Explain about TDMA channels.

9. Explain the some of the important terms of CDMA digital cellular systems.