1. (A) Attempt any THREE : 12
(a) Draw neat block diagram of communication system. State function of
each block.
(b) What is polarization ? State different types of polarization.
(c) Define Nyquist rate. What is aliasing ?
(d) What is multiplexing ? State different types of multiplexing used.
(B) Attempt any ONE : 6
(a) Draw neat block diagram of AM transmitter. Describe function of each
block .
(b) Describe polar, circular, polar equatorial, elliptical orbit of satellite.
What is geostationary orbit ?
2. Attempt any FOUR : 16
(a) Describe with neat diagram duct propagation.
(b) Draw neat block diagram of delta modulator and demodulator.
(c) What is digital to digital conversion ? State different types of polar
encoding.
(d) Describe telemetry and control sub-system of satellite.
(e) Describe analog switched service with neat diagram.
(f) State band of frequency allocated for mobile phone. State its application.
3. Attempt any FOUR : 16
(a) Compare between pulse modulation and CW modulation. (any 4 points)
(b) Name and describe antenna used in satellite communication.
(c) Define following terms :
(i) Data rate (ii) Baud rate (iii) Channel capacity (iv) Bit rate
(d) Draw
neat block
diagram of ASK
generator.
requirement of it.
(e) Describe concept of frequency reuse.
4. (A) Attempt any THREE : 12
(a) State call processing steps in cellular system.
State bandwidth
(b) With neat diagram describe principle of FDM.
(c) Define FM. State ideal and practical bandwidth requirement of FM.
(d) Describe ground wave propagation. State its application.
(B) Attempt any ONE : 6
(a) Describe PCM transmitter with the help of neat diagram. What is
quantization error ?
(b)Draw neat block diagram of cellular system and describe each block.
5. Attempt any FOUR : 16
(a) Draw block diagram of BPSK transmitter. State two advantages of it.
(b) Find percentage modulation when Emax = 132 Vpp & Emin = 28 Vpp
Draw AM waveform.
(c) Compare PPM and PWM w.r.t. (i) Bandwidth (ii) Transmitted power (iii)
Variable parameter of carrier (iv) Output waveform
(d) Draw frequency spectrum of AM. State two advantages of FM over AM.
(e) Compare between AM and ASK. (any four points)
(f) Describe B8ZS coding scheme.
6. Attempt any FOUR : 16
(a) Define PPM. Describe generation of PPM.
(b) Describe azimuth angle and elevation angle.
(c) With suitable example describe HDB3.
(d) Define fading. State its importance.
(e) Describe analog hierarchy
Good Luck and All the Best
Q.1 (a) Attempt any THREE of the following.
12 Marks
a) Describe modulation index with waveform if the modulating
voltage of 5volts is modulated with 10 volts of carrier. Calculate
percentage of modulation.
b) Compare AM and FM.
c) State and prove sampling theorem.
d) Describe the Duct propagation and Multiple hopping.
e) Describe space wave propagation with suitable diagram.
Q.1 (b) Attempt any ONE of the following.
06 Marks
a) Draw and describe working principle of QPSK.
b) Draw uplink model and downlink model of satellite
communication system.
Q.2 Attempt any FOUR of the following.
16
Marks
a) Draw and describe the block diagram of ADM.
b) What is line coding give the classification of line coding.
c) Draw block diagram of Radio communication system and explain.
d) List the various type of DSL. What is the significance of upstream
and downstream stream in ADSL.
e) Compare TDMA with FDMA (Any 4 points)
f) Give one application for each of following bands used for
communication satellites (i) UHF band (ii) S-band
(iii) C- band
(iv) X band
Q.3 Attempt any FOUR of the following.
16
Marks
a) Describe the concept of frequency reuse scheme.
b) Convert the bit stream 1001110001 into a)NRZ b)RZ
c)MANCHESTAR formats
c) Compare Analog and Digital Communication
d) Describe the working principle of parabolic dish and Horn feed
antenna
e) Describe principle of CDMA and discuss its advantages.
Q.4 (a) Attempt any THREE of the following
12 Marks
a) List the type of electronic communication and the basis of type of
transmission media.
b) List the different types of distortions in Delta modulation .Show
them with the help of graphical representation
c) Describe the concept of actual height and virtual height.
d) Describe the various layers of ionosphere with neat sketch. Along
with there application.
Q.4 (b) Attempt any ONE of the following.
06 Marks
a) Draw and describe the block diagram Armstrong(indirect) FM
transmitter
b) Give the application of satellite communication. (Any Four) .Give
the frequency band used is satellite communication.
Q.5 Attempt any FOUR of the following.
16
Marks
a) Compare ASK and FSK.
b) What is modulation,Explain the need modulation in details.
c) What do you mean by sampling. What are the different types.
Describe any one.
d) Draw the wave form for representation of AM and FM in frequency
and time domain.
e) Compare PCM with delta modulation (Four Point)
f) Describe HDB3 and B8ZS with wave form.
Q.6 Attempt any FOUR of the following.
16
Marks
a) Describe the generation of DPSK with the help wave form.
b) Draw the block diagram of cellular mobile phone and describe the
function of each block.
c) Describe with neat Labeled Diagram of Super Heterodyne
Recevier.
d) Define the following terms
I.Elevation angle II.Azimuth angle
III.MTSO IV.Base station
e) Describe the Digital hierarchy.
Good Luck and All the Best