Name of the College : SREE CHAITANYA COLLEGE OF ENGINEERING
University : JNTUH
Department : Electronics And Communication Engineering
Subject Code/Name : 07A70404/CELLULAR AND MOBILE COMMUNICATIONS
Year/Sem : IV/I
Website : scce.ac.in
Document Type : Model Question Paper
Download Model/Sample Question Paper : https://www.pdfquestion.in/uploads/scce.ac.in/4937-07A70404-CELLULARANDMOBILECOMMUNICATIONS.pdf
Cellular & Mobile Communications Question :
Code No: 07A70404 R07 Set No. 2
IV B.Tech I Semester Examinations,December 2011
Related : Sree Chaitanya College Of Engineering 07A70403 Television Engineering B.Tech Question Paper : www.pdfquestion.in/4938.html
Common to Electronics And Computer Engineering, Electronics And Telematics, Electronics And Communication Engineering
Time: 3 hours
Max Marks: 80
Answer any FIVE Questions :
All Questions carry equal marks :
1. Discuss in detail point-to-point path loss prediction model. Discuss the factors that effect the accuracy of prediction. [16]
2. (a) Draw the symmetrical sum pattern, symmetrical dierence pattern and nullfree pattern and compare them.
(b) Draw the directional antenna configuration for 1200 sector (90 channels) and explain how interference is reduced? [8+8]
3. (a) Explain how a one setup channel is used for both paging and access?
(b) What are the sectorization methods of the cell configuration?
(c) How a call is assigned to underlaid/overlaid cells? [6+6+4]
4. (a) Discuss the amplifier noise in cellular frequency band and derive the expression for noise figure.
(b) Explain the operation of a cellular system in detail. [6+10]
5. (a) Explain how a mobile hando message can align a time in TDMA Digital Cellular System?
(b) How many channels are there in TDMA Digital Cellular System? What type of functions are performed by them? [8+8]
6. (a) Explain the eect of umbrella pattern antennas?
(b) How the use of parasitic elements give the reduction in cochannel interference? Explain. [8+8]
7. (a) For a cellular system, If blocking probability is 40% and assuming each subscriber generates 0.1 Erlangs trac load, find the no. of. subscribers if no. of. channels are
i. 1
ii. 5
iii. 10
iv. 20
v. 100. Use Erlang B model charts.
(b) In a total 33MHz of BW allocated to a particular FDD system which uses two 25kHZ simplex channels to provide full duplex voice & control channels. Compute the no. of channels available per cell if a system uses
i. four cell reuse
ii. seven cell reuse
iii. 12 cell reuse.
1 MHz of allocated spectrum is dedicated to control channels. Determine a equitable distribution of control & Voice channels in each cell for each of three systems. [8+8]
8. (a) What type of hando is used when a call initiated in one cellular system and enter another system before terminating? Explain how it works.
(b) Explain how the coverage is increased for a noise-limited system by the parameters of the system. [8+8]
Code No: 07A70404
R07 Set No. 4
1. (a) Explain about foliage loss in detail.
(b) Discuss the merits of point-to-point model. [8+8]
2. (a) Explain how the handos implemented based on signal strength?
(b) How the dropped call rate is related to the capacity and voice quality.
(c) What are the dierent factors that limit the size of splitting cells? [6+4+6]
3. (a) Explain the inecient spectrum utilization based on the existing mobile systems MTS & IMTS.
(b) Explain the history of 800MHz spectrum allocation to cellular systems. [8+8]
4. (a) Explain how setup channels are act as control channels in a cellular system ?
(b) Explain the Forcible-borrowing channel assignment Algorithm and how to implement it? [8+8]
5. (a) Distinguish between permanent splitting and dynamic splitting.
(b) From a Normal case, Derive the desired C/I in an omni directional antenna system. [8+8]
6. (a) Draw the symmetrical sum pattern and compare it with symmetrical difference pattern.
(b) Draw the directional antenna configuration for 1200 sector (45 channels) and explain how interference is reduced? [8+8]
7. (a) Prove that k=7 cell pattern does not provide a sucient frequency reuse distance even when ideal conditions of at terrain is assumed.
(b) Explain how location, height and configuration of antennas are selected in a base station, to avoid cochannel interference. [10+6]
8. (a) Why HLR and VLR are required in Network and Switching subsystem? Differentiate them.
(b) What are the dierent types of logic channels? How these are dier from physical channels? [8+8]