Sinhgad College of Engineering, Pune
Department of Electronics & Telecommunication
PCS ORAL QUESTIONS BANK
1) What do you understand by Communication?
2) Explain different modes used for communication.
3) What are the different types of communication systems?
4) What are the basic elements of a communication system?
5) Define Modulation
6) Explain the need for Modulation.
7) What is Amplitude Modulation?
8) What is the modulation index of AM?
9) What are different types of AM?
10) What are the different methods to calculate the modulation index?
11) What is the effect of change in modulating signal amplitude on the modulation index?
12) What is the effect of change in modulating signal frequency on the modulation index?
13) Explain over modulation & under modulation.
14) Draw the AM wave in the time domain and frequency domain for m<1, m=1, m>1 and m=0.
15) Write down the mathematical equation of AM Wave.
16) What is the transmission efficiency of AM?
17) What is the difference between SSB and VSB?
18) What is the application of VSB?
19) How to calculate the power of DSBFC, DSBSC and SSB?
20) How to demodulate AM
21) What is a superheterodyne receiver?
22) Draw the block diagram of the AM superheterodyne receiver
23) What is the AM Broadcasting range?
24) What are the advantages of SSB-SC modulation?
25) What is the range of frequencies allotted for commercial AM and FM broadcasts?
26) What are the disadvantages of the AM technique?
27) What is AGC?
28) What do you mean by heterodyning?
29) How image frequency rejection can be done?
30) What is double spotting and how it can be reduced?
31) Why the local oscillator frequency is always kept higher than RF frequency?
32) Why is SSB not used for broadcasting?
33) What are the applications of VSB?
34) What is pre-emphasis and de-emphasis?
35) What is Frequency Modulation?
36) What is the ideal bandwidth of FM?
37) What is the modulation index of FM?
38) What is pre-emphasis and de-emphasis in FM?
39) What is the name of IC to generate FM and demodulate FM?
40) What is Carson’s rule?
41) What is the practical bandwidth equation of FM?
42) Write down the mathematical equation of FM Wave.
43) Write down the mathematical equation of PM Wave.
44) Draw the spectrum of FM.
45) What are the generation methods of FM?
46) Compare NBFM and WBFM with applications.
47) What is the FM Broadcasting range?
48) Draw the block diagram of the FM superheterodyne receiver.
49) What are the disadvantages of FM over AM?
50) Write down the equation of Intermediate frequency.
51) What is the Sampling Theorem? How to convert a Continuous time signal into Discrete time?
52) What is Nyquist's criteria for the sampling?
53) What are the types of sampling?
54) What is the aliasing effect?
55) How to eliminate aliasing effect distortion?
56) What is pulse modulation?
57) What is the difference between PAM, PWM and PPM
58) What is PCM? Explain the block diagram of PCM?
59) How to convert analog signals into digital?
60) What is digital modulation?
61) What is Quantizer?
62) What is encoder?
63) What is the S/N ratio of PCM?
64) What is the BW equation of PCM?
65) What is the bit rate of PCM?
66) What is the sampling frequency for voice signals? Justify your answer.
67) What is aperture effect?
68) How to eliminate aperture effect distortion?
69) What is DM?
70) What is ADM?
71) What is the limitation of DM?
72) Explain the term companding.
73) What is Quantizer?
74) What is multiplexing? Explain its types.
75) What is multiplexing and its application?
76) What is frequency division multiplexing (FDM)?
77) What is inter-symbol interference?
78) What is the bandwidth of a signal?
79) On which factor does the bandwidth in the data transmission depend?
80) What is the difference between a half-duplex and full full-duplex communication system?
81) What is the difference between the sensitivity and selectivity of a communication receiver?
82) What is a noise figure?
83) What do you mean by diagonal clipping?
84) What is line code or data formatting?
85) What are unipolar NRZ coding techniques?
86) What is the difference between unipolar NRZ, polar NRZ & Bipolar NRZ coding techniques?
87) What is baseband signal?
88) What is a passband pass signal?
89) What is mean coherent detection techniques
90) What is mean noncoherent detection techniques
91) What is the difference between demodulation & detection?
***************** All the Best *********************
