Download PTU (I.K.Gujral Punjab Technical University (IKGPTU)) B-Tech (Bachelor of Technology) (AR)- Automation-And-Robotics 2020 December 5th Sem 70481 Communication Systems Previous Question Paper
Total No. of Pages : 02
Total No. of Questions : 18
B.Tech. (Automation & Robotics) (2012 & Onwards)
B.Tech. (Electronics & Electrical) (2012 to 2017)
B.Tech. (Electrical & Electronics) (2013 Onwards)
(Sem.?5)
COMMUNICATION SYSTEMS
Subject Code : BTEEE-501
M.Code : 70481
Time : 3 Hrs. Max. Marks : 60
INST RUCT IONS T O CANDIDAT ES :
1 .
SECT ION-A is COMPULSORY cons is ting of TEN questions carrying TWO marks
each.
2 .
SECT ION-B c ontains F IVE questions c arrying FIVE marks eac h and s tud ents
have to atte mpt any FOUR q ues tions.
3 .
SECT ION-C contains THREE questions carrying T EN marks e ach and s tudents
have to atte mpt any T WO questio ns.
SECTION-A
Answer briefly :
1.
What is multilevel phase and amplitude modulation techniques?
2.
Distinguish between bandpass and baseband transmission.
3.
State the relationship between modulation index, peak frequency deviation and
modulating frequency.
4.
Distinguish between frequency deviation and carrier frequency swing.
5.
What is the need of pre-emphasis in frequency modulation?
6.
Define Nyquist rate and Nyquist Interval.
7.
What do you mean by data compression?
8.
Differentiate between coherent, non-coherent and differential-coherent detectors.
9.
List the advantages of digital representation of analog signal.
10. Compare three main SSB generation systems in terms of their characteristics.
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SECTION-B
11. Compare the features of AM, FM and PM
12. An AM commercial broadcast-band receiver (535kHz-1605 kHz), an input filter is used
with Q- factor of 54. Determine its bandwidth at low and high ends of RF spectrum.
13. Explain stereophonic FM broadcast receiver.
14. Explain the operation of binary frequency shift keying.
15. What do you mean by Multiplexing? Explain with diagram time division Multiplexing.
SECTION-C
16. What is the significance of noise triangle in FM? Compare the phasor diagram of FM and
AM.
17. State and prove sampling theorem.
18. The equation of an angle modulated voltage e = 10 sin (108t + 3 sin 104t). What form of
angle modulation is this? Calculate the carrier and modulating frequencies, the
modulation index and deviation and power dissipated in 100 resistors.
NOTE : Disclosure of Identity by writing Mobile No. or Making of passing request on any
page of Answer Sheet will lead to UMC against the Student.
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This post was last modified on 13 February 2021