SC PYQ’s(2018 To 2024)

CH:-1
1) Explain various frequency bands used for satellite communication.
2) Draw and explain the block diagram of satellite communication in detail.
3) Explain advantages of satellite communication over terrestrial communication
4) Give comparison of LEO, MEO and GEO satellite orbits and gives application also.
5) Write a brief history of Satellite Systems.
6) State the advantages, drawbacks, applications and frequency bands used for satellite communication.
7) Write a note on Station Keeping explaining different Station Keeping Maneuvers.
8) What is station keeping?
9) Explain the term: Station keeping
10) What is station keeping?
11) Explain the term: Station keeping
12) Explain the principles and architecture of satellite communication. How do satellites function as key
components in the communication system?
13) Explore the different frequency bands used for satellite communication. Discuss the reasons behind using
specific frequency bands.
14) What are the advantages of satellite communication systems?
15) Describe briefly any four services provided by satellite
16) Explore the various applications of satellite communication across different sectors, including
telecommunications, broadcasting, remote sensing, and navigation. Explain the impact of satellite
technology on these domains and its significance in today's world.
17) Show the table containing different frequency bands (used with satellite communication) along with Band
designation.
18) What are the advantages of satellite communication?
19) Explain the architecture of a satellite communication system.
20) Compare and contrast the different frequency bands used for satellite communication and their
applications.
21) Discuss the applications of satellite communication in military, broadcast, and remote sensing.
22) Describe the brief history of satellite systems in satellite communication.
23) Analyze the impact of satellite communication on global communication systems and the future prospects
of the technology.

CH:-2
1) Define (1) Apogee (2) Perigee (3) Subsatellite Path

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2) State Kepler’s three laws of planetary motion.
3) Define: (1) Kepler’s first law with figure. (2) Kepler’s Second law with figure.
4) Describe Kepler’s Third law
5) Describe Kepler’s Third law
6) Describe: (1) Kepler’s first law with figure. (2) Kepler’s Second law with figure.
7) State Kepler’s three laws of planetary motion with figures and equations.
8) Define: (1) subsatellite path. (2) Apogee (3) Perigee (4) Line of apsides
9) Define: (1) Ascending node. (2) Descending node (3) Line of Nodes (4) Inclination angle
10) Define Inclination, Prograde orbit, Argument of perigee, Right ascension of ascending node.
11) Explain Orbit perturbations and Effects of a nonspherical earth With necessary equations.
12) Explain the Effect of a non spherical earth on orbital path of satellite.
13) Define the term :Atmospheric Drag.
14) Describe polar orbiting satellites with figure.
15) Calculate the radius of a circular orbit for which the period is 1 day.
16) Define elevation angle and azimuth angle.
17) Calculate the radius of a circular orbit for which the period is one day.
18) A geostationary satellite is located at 90°W. Calculate the azimuth angle for an earth-station antenna at
latitude 35°N and longitude 100°W
19) Define: Prograde orbit, retrograde orbit, Mean anomaly
20) Define: True anomaly, Argument of perigee, Apogee, Perigee
21) Define following terms: (1) Apogee (2) Perigee (3) Line of apsides
22) List the orbital elements and explain each of them in detail.
23) Explain three laws of Kepler’s for planetary motion in detail.
24) Determine the orbital period of a satellite for a circular orbit.
25) Mention apogee, perigee and apogee height, perigee height.
26) What are Kepler’s three laws of planetary motion? Give the mathematical formulation of Kepler’sthird law
of planetary motion.
27) Explain the difference between Sidereal Day and Solar Day.
28) What is the difference between a solar day and a sidereal day?
29) By using of equation and figure properly explain the look angle determination of satellite.
30) Explain what is meant by (a) line of apsides and (b) line of nodes. Is it possible for these two linesto be
coincident?
31) What are the conditions required for an orbit to be geostationary?
32) What are the conditions required for an orbit to be geostationary?
33) Define the terms apogee and perigee in the context of satellite orbits. How are they different for elliptical
orbits, and what is their significance?
34) Calculate the orbital period of a satellite in a given orbit. Explain the factors that influence the orbital
period and its importance in satellite design and positioning.

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 35) Provide a detailed explanation of Kepler's laws and their relevance to satellite orbits. How do these laws
describe the motion of satellites and help in predicting their positions in space?
36) Compare and contrast the concepts of a solar day and a sidereal day. Explain how these different time
measurements relate to satellite orbit determination and synchronization with ground stations.
37) What do you mean by near geostationary orbit?
38) Calculate the apogee and Perigee heights for the orbital parameters e=0.0011501, a=7192.335 km and
mean earth radius=6371 km.
39) Calculate the apogee and Perigee heights for the orbital parameters e=0.0011501, a=7192.335 km and
mean earth radius=6371 km.
40) Define: (1) Ascending node (2) descending node (3) Line of apsides
41) The apogee and perigee distance of a satellite orbiting in an elliptical orbit are respectively 45000 km and
7000 km.Determine the following: (1) Semi-major axis of the elliptical orbit. (2) Orbital eccentricity (3)
Distance between the center of the earth and the center of elliptical orbit.
42) Explain the concept of a geostationary orbit and its significance in satellite communication.

CH:-3
1) Explain Attitude & Orbit Control system (AOCS).
2) Draw and Explain block diagram of TTC&M system.
3) With diagram Explain the TT&C Subsystem in detail.
4) Briefly describe the Three axis method of satellite stabilization.
5) Define the terms Roll, pitch and yaw.
6) Draw & Explain block diagram of Transponder.
7) Write short note on Satellite Antennas.
8) Draw the block diagram of the satellite Transponder. Explain frequency reuse in transponders.
9) What is the advantage of TWTA used aboard the satellites.
10) Explain limits of visibility with figure.
11) Describe with figure: The attitude control in detail.
12) Draw and Explain block diagram of TT&C system.
13) Give the difference between Attitude control and Orbital Control.
14) Write short note on Satellite Antennas.
15) Explain Single conversion transponder and Double conversion transponder in detail.
16) Explain Attitude control and Orbital Control of a satellite.
17) What is the purpose of Telemetry, Tracking, Command, and Monitoring in Satellite communication?
Explain in detail.
18) Explain the block diagram of Satellite Transponder. Also explain the frequency reuse techniquefor
Transponder.

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 19) Explain why some satellites employ cylindrical solar arrays, whereas others employ solar-sail arraysfor the
production of primary power. State the typical power output to be expected from each type. Why is it
necessary for satellites to carry batteries in addition to solar-cell arrays?
20) Describe the importance and functions of the Attitude and Orbit Control System (AOCS) in a satellite. How
does AOCS ensure the satellite's proper orientation and positioning in space?
21) Explain the significance of the Power sub-system in a satellite. How is power generated, stored, and
distributed on a satellite, and what factors influence the choice of power sources and storage methods?
22) Define and explain the roles of Telemetry, Tracking, Command, and Monitoring (TTC&M) subsystems in a
satellite system. How do these subsystems contribute to the successful operation of a satellite?3
23) Define following terms: (1) Inclination (2) Semi-major axis (3) Prograde orbit (4) Footprint
24) Explain the space segment.
25) What is the purpose of the attitude and orbit control system in a satellite?
26) Discuss the functions of the Telemetry, Tracking, Command and Monitoring (TTC&M) subsystem in a
satellite
27) Analyze the power sub-system of a satellite and explain the methods used for power generation and
storage in a satellite.
28) Briefly describe the three-axis method of satellite stabilization.
29) Explain the block diagram of Satellite Transponder. Also explain the frequency reuse technique for
Transponder.

CH:-4
1) Define Earth Eclipse of Satellite.
2) Define the term: Doppler Shift.
3) Explain Sun transit outage phenomena.
4) What is sun synchronous obrit?
5) Explain sun Transit outage.
6) Explain sun Transit outage.
7) What is sun transit outage? What is its effect and remedy for it?
8) What is Earth eclipse of Satellite? Are there any ways of avoiding eclipse during lifetime of satellite.
9) Describe the phenomenon of a solar eclipse on a satellite. How does a solar eclipse affect satellite
communication, and what challenges does it pose?
10) Explain the concept of sun transit outage phenomena in satellite communication. What are the effects of
sun transit outages, and how can they be mitigated?
11) Explain earth eclipse of satellite with figure.
12) What is the sun transit outage phenomenon and its effect on satellite communication?

CH:-5
1) Explain what is meant by EIRP.

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2) Define Equivalent Isotropic Radiated Power (EIRP) with equation.
3) What is EIRP? Show the relationship between Power flux density and EIRP.
4) Derive Friis transmission equation for received power in any radio link.
5) Discuss the various design issues related with uplink design and give the Expression C/N ratio forthe same.
6) Explain Noise Power Calculation in Satellite Link Budget.
7) Explain C/N ratio calculations in clean air and rainy conditions.
8) Define following terms.(1) Noise factor (2) Noise Temperature (3) Carrier to Noise ratio
9) Explain various uplink path losses in satellite communication.
10) Explain how to compute uplink and downlink C/N ratios for a typical satellite link.
11) Derive the equation for Carrier to Noise ratio(C/No) at receiver input.
12) What is EIRP? Show the relationship between Power flux density and EIRP.
13) Define Downlink. Draw a pictorial representation of a Downlink. Show the power budget calculations for
a downlink path.
14) A satellite downlink at 12 GHz operates with a transmit power of 6 W and an antenna gain of 48.2 dB.
Calculate the EIRP in dBW.
15) The range between a ground station and a satellite is 42000 km. Calculate the free space loss afrequency
of 6 GHz.
16) The uplink C/No ratio is 88 dBHz and downlink value is 78 dBHz.Calculate overall C/No ratio.
17) Discuss the importance of Carrier-to-Noise (C/N) ratio calculations in both clean air and rainy conditions.
Explain how variations in weather and atmospheric conditions can affect the C/N ratio and signal quality
in satellite communication.
18) Explain the concept of flux density in satellite communication. How is received signal power calculated
based on flux density and antenna characteristics?
19) Describe the significance of system noise temperature in a satellite receiver. How is system noise
temperature calculated, and how does it impact the overall performance of the receiver?
20) Describe the process of drafting a satellite link budget in detail. Include all the major factors that need to
be considered, such as transmit power, path loss, antenna gains, and noise temperature. How is the link
budget used to ensure reliable communication in different weather conditions?
21) Explain what is meant by EIRP. A transmitter feeds a power of 10W into an antenna which has again of 46
dB. Calculate the EIRP in (i) Watts (ii) dBW.
22) Explain what is meant by saturation flux density. The power received by a 1.8-m parabolic antennaat 14
GHz is 250 pW. Calculate the power flux density (a) in W/m2 (b) in dBW/m2 at the antenna.
23) Explain atmospheric losses in radio wave propagation.
24) What is link power budget equation? Explain briefly
25) Describe the Noise temperature of absorptive networks with necessary equations and derive the equation
for Overall system noise temperature.
26) Describe: Feeder losses and antenna misalignment losses with figures.

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 27) Describe Noise temperature of absorptive networks and show that the noise factor of a lossy network is
equal to its power loss.
28) Define: equivalent isotropic radiated power
29) With diagram Explain the overall system noise temperature and write its equation. Also derive the
equation for carrier to Noise ratio.
30) Draw the complete satellite circuit which includes combined uplink and downlink. Derive the equation for
combined Noise-to-carrier ratio N0/C.
31) What is a satellite link budget in satellite communication?
32) Explain the received signal power equation used in satellite link budget calculations.
33) Discuss the impact of weather conditions on the satellite link budget and C/N ratio calculations.

CH:-6
1) Explain Various modulation schemes used in satellite communication.
2) Compare FDMA, TDMA and CDMA techniques.
3) Describe: Demand assigned TDMA.
4) With diagram explain the function a basic CDMA system.
5) Describe: Preassigned TDMA with figures.
6) What is Demand Assigned FDMA.
7) What is SPADE System in channeling scheme.
8) Explain the SPADE system
9) Describe preassigned FDMA with diagram.
10) Explain Demand assigned FDMA
11) What is CBTR (Carrier and bit time recovery)?
12) List the advantage and disadvantage of FDMA, TDMA and CDMA.
13) Explain briefly code division multiple access.
14) Compare FDM/FM-FDMA and SCPC-FDMA
15) Explain preassigned FDMA in detail.
16) Give the difference between Multiplexing techniques and Multiple access techniques.
17) Explain the SPADE system.
18) What is SCPC?
19) What is SCPC?
20) Analyze the time division multiple access (TDMA) technique used in satellite communication and discuss
its applications.
21) Define multiple access in satellite communication. What does it mean, and why is it a critical aspect of
satellite network design and operation?
22) Explain briefly code division multiple access.

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23) Compare and contrast the Time Division Multiple Access (TDMA), Frequency Division Multiple Access
(FDMA), and Code Division Multiple Access (CDMA) schemes used in satellite communication. How do
these multiple access methods differ in their approach and suitability for various scenarios?
24) What is an TDMA? What are the advantages?
25) List the types of Multiple Access Scheme used in the satellite communication and give its comparisons.
26) What is the meaning of multiple access?
27) What is meant by space division multiple access?
28) With the help of equation and block diagram, properly explain the Code Division multiple Accessin detail.
29) With diagram explain satellite switched TDMA.
30) What do you mean by multiple access technique?Explain time division multiple access in detail.
31) Compare Preassigned FDMA and Demand assigned FDMA.
32) Explain in brief Demand Assigned FDMA.
33) Define Direct sequence Spread Spectrum.
34) Explain Preassigned TDMA with diagram.
35) Explain satellite switched TDMA with diagram.
36) With diagram explain the function of basic CDMA system.
37) Illustrate the basic TDMA concept in which the stations transmit bursts in sequence. Draw necessary
figures.
38) Discuss the advantages and disadvantages of each multiple access scheme, and suggest situations where
each would be most appropriate in satellite communication.
39) What is the meaning of multiple access?
40) What is meant by space division multiple access?
41) List the types of Multiple Access Scheme used in the satellite communication and give its comparisons.

-:Prepared By Sahil Gohel:-