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GUJARAT TECHNOLOGICAL UNIVERSITY

BRANCH NAME: Electronics & Communication Engineering (11), Electronics &

Telecommunication Engineering (12)

SUBJECT NAME: Satellite Communication

SUBJECT CODE: 2171007

B.E. 7thSEMESTER

Type of course: Undergraduate

Prerequisite: Electronics Communication, Digital Communication

Rationale: The course aims to:

1 To understand the basics of satellite communications

2 To understand different satellite communication orbits

3 To understand the satellite segment and earth segment

4 Provide an in-depth treatment of satellite communication systems operation and planning

5 To analyze the various methods of satellite access

6 Link budgets & planning

7 Review the state of the art in new research areas such as speech and video coding, satellite

networking and satellite personal communications

8 To learn Digital audio/video broadcasting using satellites

9 To understand various applications of satellite communications

Teaching and Examination Scheme:

Teaching Scheme Credits Examination Marks Total

Marks L T P C Theory Marks Practical Marks

ESE

(E)

PA (M) ESE (V) PA

(I) PA ALA ESE OEP

3 0 2 5 70 20 10 20 10 20 150

Content:

Sr. No. Content Total

Hrs

% Weightage

1 Introduction to Satellite Communication:

Historical background, Basic concepts of Satellite

Communications, Communication Networks and Services,

Comparison of Network Transmission technologies, Orbital and

Spacecraft problems, Growth of Satellite communications.

2 5

2 Orbits and Launching Methods:

Introduction, Kepler’s First Law,Kepler’s Second Law, Kepler’s

Third Law, Definitions of Terms for Earth-Orbiting Satellites,

Orbital Elements, Apogee and Perigee Heights, Orbit Per

turbations, Effects of a non spherical earth, Atmospheric drag.

5 10

3 The Geostationary Orbit:

Introduction, Antenna Look Angles, The Polar Mount Antenna,

Limits of Visibility, Near Geostationary Orbits, Earth Eclipse of

Satellite, Sun Transit Outage, Launching Orbits

4 10

4 Radio Wave Propagation:

Introduction, Atmospheric Losses, Ionospheric Effects, Rain

Attenuation, Other Propagation Impairments

2 5

5 Polarization:

Introduction, Antenna Polarization, Polarization of Satellite

Signals, Cross Polarization, Discrimination, Ionospheric

Depolarizaon, Rain Depolarization, Ice Depolarization

2 5

6 The Space Segment :

Introduction, The Power Supply, Attitude Control, Spinning

satellite stabilization, Momentum wheel stabilization, Station

Keeping, Thermal Control, TT&C Subsystem, Transponders, The

wideband receiver, The input demultiplexer, The power amplifier,

The Antenna Subsystem

4 15

7 The Earth Segment:

Introduction, Receive-Only Home TV Systems, The outdoor unit,

The indoor unit for analog (FM) TV, Master Antenna TV System,

Community Antenna TV System, Transmit-Receive Earth Stations

4 10

8 The Space Link :

Introduction, Equivalent Isotropic Radiated Power, Transmission

Losses, Free-space transmission, Feeder losses, Antenna

misalignment losses, Fixed atmospheric and ionospheric losses,

The Link-Power Budget Equation, System Noise, Carrier-to-Noise

Ratio, The Uplink, Saturation flux density, Input backoff,

Downlink, Output back-off, Combined Uplink and Downlink C/N

Ratio

5 15

9 Satellite Access:

Introduction, Single Access, Preassigned FDMA, Demand-

Assigned FDMA, Spade System, TDMA, Preassigned TDMA,

Demand-assigned TDMA, Satellite-Switched TDMA, Code-

Division Multiple Access

4 10

Suggested Specification table with Marks (Theory):

Distribution of Theory Marks

R Level U Level A Level N Level E Level C Level

15 15 10 10 10 10

Legends: R: Remembrance; U: Understanding; A: Application, N: Analyze and E: Evaluate

C: Create and above Levels (Revised Bloom’s Taxonomy)

Note: This specification table shall be treated as a general guideline for students and teachers. The actual

distribution of marks in the question paper may vary slightly from above table.

Reference Books:

1. Satellite Communications, by Dennis Roddy(Fourth edition),McGraw Hill.

2. Satellite Communication Systems Engineering, by Wilbur L. Pritchard, Henri G.

Suyderhoud, Robert A. Nelson ( Second Edition ), Pearson

3. Satellite Communication, by Timothy Pratt, Charles Bostian, Jeremy Allnutt(Second

Edition),

John Wiley & Sons.

4. Satellite Technology, Principles and Applications, by Anil K. Maini, Varsha Agarwal

(Second Edition ), Wiley.

Course Outcome:

After successful completion of the course, the students will be able to:

1. Understand principle, working and operation of various sub systems of satellite as well as

the earth station.

2. Apply various communication techniques for satellite applications

3. Analyze and design satellite communication link

4. Learn advanced techniques and regulatory aspects of satellite communication

5. Understand role of satellite in various applications

10 Direct Broadcast Satellite Television and Radio:

C-Band and Ku-Band Home Satellite TV, Digital DBS TV, DBS-

TV System Design, DBS-TV Link Budget, Error Control in Digital

DBS-TV, Master Control Station and Uplink, Installation of DBS-

TV Antennas, Satellite Radio Broadcasting, Digital Video

Broadcast(DVB) Standards, Digital Video Broadcast – Terrestrial

(DVB-T)

4 10

11 Satellite Mobile and Specialized Services:

Introduction, Satellite Mobile Services, VSATs, Radarsat, Global

Positioning Satellite System (GPS), Orbcomm, Iridium

3 5

Total 39

Suggested List of Experiments:

1. Understanding the basic concepts of satellitecommunication

2. To setup a communication link betweenuplink transmitter and downlink receiverusing

Satellite.

3. To setup an Active satellite communicationlink and demonstrate link fail operation

4. To communicate voice & Video signal throughsatellite link

5. Observe the effect of Different combinationsof uplink and downlink frequencies on

satellitelink.

6. To transmit and receive three separatesignals (Audio, Video , Tone) simultaneouslythrough

satellite link

7. To transmit and receive function generatorsignals through satellite link.

8. To measure the signal parameters in ananalog FM/FDM TV satellite link.

9. To transmit digital waveforms through asatellite communication link.

10. To Calculate Bit Error Rate in a satellitecommunication link.

Design based Problems (DP)/Open Ended Problems:

1. To write a program to observe thevariations in the antenna lookangles for the earth

stationantennas.

2. To write a program to calculate todetermine the limits of visibility foran earth station.

3. To obtain the plot of Orbital altitudeversus satellite antenna diameter.

4. To write a Program for Estimatedtopospheric attenuation due toOxygen and water.

5. To write a Program for plot ofSemimajor axis versus rate ofchange of argument of perigee.

6. To write program to calculate therain attenuation(in dB) forhorizontal polarization,

verticalpolarization and circularpolarization for satellite wavepropagation.

7. To write a program to determinethe combined carrier to noisepower spectral density ratio

forsatellite link budget.

8. To determine the degradation inthe downlink C/I ratio whensatellite orbital spacing is

reduced.

9. To write a program to plot thedegradation in downlink C/I.

10. To plot the variation in Carrier toNoise power spectral densityratio(uplink,downlink

andcombined)for changes in the inputSFD for uplink and EIRP fordownlink.

11. To write a program for plotting Halfpower beamwidth Vs. maximumnumber of days sun

transit occursat an earth station.

12. To write a program for plotting BER vsEb/No for BPSK signal forSatCom.

List of Open Source Software/learning website:

1. http://nptel.iitm.ac.in/course.php

2. http://ocw.mit.edu

3. www.radio-electronics.com

4. http://en.wikipedia.org

5. www.youtube.coms

ACTIVE LEARNING ASSIGNMENTS: Preparation of power-point slides, which include

videos, animations, pictures, graphics for better understanding theory and practical work – The

faculty will allocate chapters/ parts of chapters to groups of students so that the entire syllabus to

be covered. The power-point slides should be put up on the web-site of the College/ Institute,

along with the names of the students of the group, the name of the faculty, Department and College

on the first slide. The best three works should submit to GTU.

1

Seat No.: ________ Enrolment No.___________

GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII (NEW) - EXAMINATION – SUMMER 2017

Subject Code: 2171007 Date: 02/05/2017 Subject Name: Satellite Communication(Departmental Elective - II) Time: 02.30 PM to 05.00 PM Total Marks: 70 Instructions:

1. Attempt all questions. 2. Make suitable assumptions wherever necessary. 3. Figures to the right indicate full marks.

Q.1 (a) Write few significant details of satellites: 1] Sputnik 2] INTELSAT 07

(b) With a diagram, justify the state of “Free Fall” of a satellite body. 07

Q.2 (a) A satellite in orbit has got an orbital period of a solar day. Calculate the radius

of the orbit. An observer on earth sees that the satellite is drifting. Find the rate

of drift of the sub satellite point around the equator in degrees per solar day.

Conclude whether the satellite is moving eastwards or westwards.

07

(b) Using a neat sketch, show and explain

(1) Circular orbit

(2) Elliptical orbit

(3) Equatorial orbit

(4) Inclined orbit

(5) Polar orbit

(6) GEO orbit

(7) Molniya orbit

07

OR

(b) Classify orbits based on their height and specify at least one application of each. 07

Q.3 (a) What is the significance of a Transponder in Satellite? Explain in details. 07

(b) Define an AKM. What is the use of this unit in a launch vehicle? 07

OR

Q.3 (a) Explain in details about reliability and redundancy of satellite subsystems. 07

(b) Differentiate amongst TDMA, FDMA and CDMA systems. 07

Q.4 (a) Write a short note on different antennas used in satellites. 07

(b) How does a spinner satellite operate? Explain the principle of North South

control of a spinner satellite using IR sensors.

07

OR

Q.4 (a) Classify the typical satellite antenna coverage zones to show different types of beams

using diagram. 07

(b) How does a 3 axis stabilized satellite operate? Explain how attitude control is

done.

07

2

Q.5

(a)

Using diagrams, explain the stratiform and convective rain events. An earth

station at sea level communicates at an elevation angle of 35 degrees with a

GEO satellite. The melting level height of the stratiform rain is 3 km. (melting

layer is the region of the atmosphere where temperature changes from below

0°C to above 0°C). Find the physical path length through the rain.

07

(b) Write a short note on DBS TV systems. 07

OR

Q.5 (a) Define canting angles and tilt angles for a rain drop. Calculate the perceived

polarization tilt angle at an earth station located at 52°N, 1°E, for a vertically

polarized signal transmitted from a GEO satellite located at 60°E?

07

(b) Write a short note on GPS. 07

*************

1


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII(NEW) • EXAMINATION – WINTER 2016

Subject Code:2171007 Date:21/11/2016

Subject Name:Satellite Communication(Departmental Elective - II)

Time: 10.30 AM to 1.00 PM Total Marks: 70 Instructions:

1. Attempt all questions.

2. Make suitable assumptions wherever necessary.

3. Figures to the right indicate full marks.

Q.1 (a) Describe the following terms of Earth orbiting satellites

(1) Ascending node (2) line of apsides (3) Inclination (4) Apogee (5) True

anomaly (6) Mean anomaly (7) Retrograde orbit

07

(b) Explain Kepler’s three law of planetary motion with require expression. 07

Q.2 (a) A C-band earth station has an antenna with a transmit gain of 54 dB. The

transmitter output power is set to 100 W at a frequency of 6.100 GHz. The

signal is received by a satellite at a distance of 37,500 km by an antenna with a

gain of 26 dB. The signal is then routed to a transponder with a noise

temperature of 500 K, a bandwidth of 36 MHz, and a gain of 110 dB. Calculate

(a) path loss at 6.1 GHz. (b) power at the output port of the satellite antenna, in

dBW. (c) noise power at the transponder input (d) C/N ratio, in dB, in the

transponder (e) carrier power, in dBW and in watts, at the transponder output.

07

(b) Explain Atmospheric Losses and Ionosphere Effects for radio wave

propagation.

07

OR

(b) Explain how depolarization is caused by ionosphere, rain and ice. 07

Q.3 (a) What is the purpose of Telemetry, Tracking, Command, and Monitoring in

Satellite communication? Explain in detail.

07

(b) Explain elevation angle and azimuth angle calculation with proper derivations. 07

OR

Q.3 (a) Write a short note on Receive-Only Home TV Systems. 07

(b) Write a short note on transponder. 07

Q.4 (a) (i) What is Free space loss? The range between a ground station and a satellite

is 42,000 km. Calculate the free-space loss at a frequency of 6 GHz.

(ii) Derive Friis transmission equation for received power in any radio link.

03

04

(b) Compare FDMA, TDMA and CDMA techniques. 07 OR

Q.4 (a) Discuss the various design issues related with uplink design and give the

Expression C/N ratio for the same.

07

(b) What do you mean by multiple access technique? Explain Time Division

Multiple Access in detail.

07

Q.5 (a) How the error control done in Digital DBS-TV? Explain it. 07

(b) Write a short note on VSAT. 07

OR

Q.5 (a) Explain DBS satellite system. 07

(b) Write a short note on Global Positioning Satellite System.

07

1/1


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII (OLD) - EXAMINATION – SUMMER 2017

Subject Code: 171007 Date: 29/04/2017 Subject Name: Satellite Communication (Department Elective - I) Time: 02:30 PM to 05:00 PM Total Marks: 70 Instructions:


Q.1 (a) Explain Kepler’s three laws of planetary motion. What is the difference

between polar orbit and geostationary orbit?

07

(b) Explain the Keplerian element set. 07

Q.2 (a) Explain different Satellite services. 07

(b) Calculate the radius of a circular orbit for which the period is one day. 07

OR

(b) What is satellite communication? Draw and explain the block diagram

of satellite communication in detail.

07

Q.3 (a) Write a short note on Equipment reliability and space qualification for

Satellite Communication.

07

(b) Explain Cross-Polarization Discrimination. 07

OR

Q.3 (a) Explain the block diagram of Satellite Transponder. Also explain the

frequency reuse technique for Transponder.

07

(b) Draw the explain TT&C. 07


(b) List the types of orbits used in the satellite and give its comparison

with appropriate advantages and disadvantages.

07

OR

Q.4 (a) What is VSAT? List the applications of VSAT. Draw and explain the

block diagram of VSAT system.

07

(b) Write short notes on Master Control Station required for Direct

Broadcast Satellite Television (DBS-TV) system.

07

Q.5 (a) Explain how to compute uplink and downlink C/N ratios for a typical

satellite link.

07

(b) Explain GPS receiver operation in short.

07

OR

Q.5

(a)

Explain the spade system.

07

(b) Write differences between:

(i) Attitude control and orbital control

(ii) East-west and North-south station keeping maneuvers.

07

*************

1


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII(OLD) • EXAMINATION – WINTER 2016

Subject Code: 171007 Date: 18/11/2016

Subject Name: Satellite Communication (Department Elective - I)

Time: 10:30 AM to 01:00 PM Total Marks: 70 Instructions:




Q.1 (a) An earth station is located at latitude 12° S and longitude 52° W. Calculate the

antenna look angles for a satellite at 70° W.

07

(b) Answer the following questions: (3+2+2 Marks) 07

1 Explain Kepler’s first & second laws for planetary motion.

2 Which features are offered by Satellites that are not readily available with other

means of communications?

3 What is meant by geostationary orbit?

Q.2 (a) A satellite is in elliptical orbit with a perigee of 1000 km and an apogee of 4000 km.

Assuming a mean earth radius of 6378.14 km; determine the period of the orbit in

hours, minutes, and seconds, and the eccentricity of the orbit.

07

(b) Explain orbital elements that define earth-orbiting artificial satellites. Also discuss

the effects of the earth’s oblateness.

07

OR

(b) Describe typical tracking, telemetry, command and monitoring system for satellite. 07

Q.3 (a) Calculate the overall [C/N0] for a satellite circuit having the following parameters:

Uplink, decilogs Downlink, decilogs

[EIRP] 54 34

[G/T] 0 17

[FSL] 200 198

[RFL] 2 2

[AA] 0.5 0.5

[AML] 0.5 0.5

07

(b) Answer the following questions: (4+3 Marks) 07

1 Write brief note on satellite transponder.

2 Briefly describe the three-axis method of satellite stabilization.

OR

Q.3 (a) Explain saturation flux density and input back-off for a satellite TWT amplifier.

Find the carrier-to-noise density ratio at the satellite input for an uplink, which has

the following parameters: operating frequency 6 GHz, saturation flux density -95

dBW/m2; input backoff 11 dB; satellite [G/T] -7 dBK-1, [RFL] 0.5 dB.

07


1 For the system shown in figure below, the receiver noise figure is 12 dB, the

cable loss is 5 dB, the LNA gain is 50 dB, and the noise temperature 150 K. The

antenna noise temperature is 35 K. Calculate the noise temperature referred to

the input. Why LNA must be placed ahead of the cable?

2

2 Describe the main features and services offered by the orbcomm satellite system.

Q.4 (a) Illustrate basic TDMA concept and explain satellite switched TDMA with onboard

processing.

07

(b) Write detail note on Demand Access Multiple Access technique for satellite link. 07 OR

Q.4 (a) Describe the operation of a typical VSAT system and discuss VSAT network

architectures.

07

(b) List different NGSO orbits and explain sun synchronous orbit in detail. 07

Q.5 (a) Describe general arrangement of position locations with GPS and explain why a

minimum of four satellites must be visible at any earth location utilizing the GPS

system for position determination.

07

(b) Explain DBS-TV receiver in detail using block diagram. 07

OR

Q.5 (a) Explain GPS receiver operation in detail. 07


1 Explain prediction of XPD in brief.

2 Discuss any one propagation effect that is not associated with hydrometeors.

*************


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII EXAMINATION – SUMMER 2016

Subject Code:171007 Date:05/05/2016 Subject Name:Satellite Communication (Department Elective - I) Time:02:30 PM to 05:00 PM Total Marks: 70 Instructions:


Q.1 (a) Draw and explain block diagram of DBS-TV receiver

07

(b) Explain with block diagram: (i) Single conversion transponder

(ii) Double conversion transponder 07

Q.2 (a) Explain briefly: Sun synchronous orbit, Elliptical orbit, and Inclined orbit.

07

(b) Explain GPS position location principle with necessary diagram and

derivations. 07

OR

(b) What does the acronym VSAT stand for? Explain network architectures for

VSAT systems.

07

Q.3 (a) Draw and explain block diagram of GPS receiver.

07

(b) Explain the coding and decoding operations in DBS-TV signal with the help of

block diagram

07

OR

Q.3 (a) Describe briefly the main advantages of satellite communication and discuss the

applications of satellite communication.

07

(b) Explain basic transmission line theory and derive equation of power received in

dBW. (In terms of EIRP, Antenna gain and path loss.)

07

Q.4 (a) What are the differences between multiplexing and multiple access techniques.

Explain briefly Code division multiple access.

07

(b) Explain the design methodology for a one-way satellite communication link

with the help of one example.

07

OR

Q.4 (a) Draw and explain block diagram of telemetry, tracking, command and

monitoring system for communication satellite. 07

(b) Explain Frequency division multiple access technique for satellite links.

07

Q.5 (a) Explain Kepler’s three laws of planetary motion with necessary diagram and

equations.

07

(b) Write short note on : Satellite launch vehicles in India

07

OR

Q.5 (a) Explain propagation effects that are not associated with hydrometers.

07

(b) Write short note on : Satellite Antennas

07

1


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII EXAMINATION – WINTER 2015

Subject Code: 171007 Date: 04/12/2015

Subject Name: Satellite Communication

Time: 10:30am to 1:00pm Total Marks: 70 Instructions:




Q.1 (a) State Kepler’s three laws of planetary motion. Quote Kepler’s constant. A

satellite in an elliptical orbit around the earth has an apogee of 39,152 km and a

perigee of 500 km. What is the orbital period of the satellite? Average earth

radius is 6,378.137 km.

07

(b) What kind of forces causes the state of “Free Fall” of a satellite body so that it

can continue being in motion once it is placed in the orbit? Explain in details.

07

Q.2 (a) State any three reasons that cause Orbital Perturbations. Identify locations called

Satellite graveyards in the orbit. Explain the response of the satellite at such

locations.

07

(b) Using a neat sketch, show and explain

(1) Inclination angle

(2) Eccentricity

(3) Perigee

(4) Apogee

(5) Foci of an ellipse

(6) Semi major axis and

(7) Sub satellite point

07

OR

(b) Write a short note on TTC&M. 07

Q.3 (a) Define Downlink. Draw a pictorial representation of a Downlink. Show the

power budget calculations for a downlink path.

07

(b) What is the significance of Geosynchronous Transfer Orbit for correct

orientation of the satellite? How can we position a satellite to higher altitudes

from the LEO height with the help of GTOs? Explain any one method.

07

OR

Q.3 (a) What parameters apart from rain affect the satellite system? Explain. 07

(b) Write a short note on the solar eclipse of satellite and sun transit outage. 07

2

Q.4 (a) What kinds of batteries are used to meet the power needs of a satellite? A direct

broadcast TV satellite requires 500 W of electrical power to operate the

housekeeping functions of the satellite and 5 kW to operate its 16 high power

transponders. The longest duration of an eclipse is 70 minutes, during which

time the batteries must provide power to keep the satellite operating, but the

batteries must not discharge below 70% of their capacity. The satellite bus

operates at 48 volts. What is the current that must be supplied by the power

conditioning unit to keep the satellite operating normally? Battery capacity is

rated in Ampere hours; the product of the current (in amps) that the battery can

supply multiplied by the length of time that this current can be supplied before

the battery is fully discharged. The satellite batteries must not discharge beyond

70% of their rated capacity during eclipse. Find the battery capacity required for

this DBS-TV satellite. If batteries weigh 1.25 kg per Ampere-hour of capacity,

how much weight on this satellite is devoted to batteries? If half of the

transponders are shut down during eclipse, what saving in battery weight is

achieved?

07

(b) Define Elevation and Azimuthal angles of a satellite. Look angles for the Earth

station is at latitude 52°N and 0° E longitude at London, England, Dockyard

region. The look angle for the satellite is at latitude 0°N and 66° E longitude at

Geostationary INTELSAT, IOR primary. Find the central angle, the elevation

angle, the intermediate angle and the azimuthal angle.

07

OR

Q.4 (a) A geostationary satellite carries a C-band transponder which transmits 15 watts

into an antenna with an on-axis gain of 32 dB. An earth station is in the center

of the antenna beam from the satellite, at a distance of 38,500 km. For a

frequency of 4.2 GHz, calculate the incident flux density at the earth station in

watts per square meter and in dB W/m2. The earth station has an antenna with a

circular aperture 3 m in diameter and an aperture efficiency of 62%. Calculate

the received power level in watts and in dB W at the antenna output port.

Calculate the on-axis gain of the antenna in decibels. Calculate the free space

path loss between the satellite and the earth station. Calculate the power

received, Pr, at the earth station.

07

(b) The telemetry system of a geostationary communications satellite samples 100

sensors on the spacecraft in sequence. Each sample is transmitted to earth as an

eight-bit word in a TDM frame. An additional 200 bits are added to the frame

for synchronization and status information. The data are then transmitted at a

rate of 1 kilobit per second using BPSK modulation of a low-power carrier.

How long does it take to send a complete set of samples to earth from the

satellite? Including the propagation delay, what is the longest time the earth

station operator must wait

for a change in a parameter occurring at the spacecraft to reflect the new value

of that parameter being received via the telemetry link? Evaluate the same for a

QPSK modulated carrier;

07

Q.5 (a) Write a short note on VSAT. 07

(b) Explain the working of the GPS system. 07

OR

Q.5 (a) Write a short note on Equipment Reliability and Space Qualification. 07

(b) How is error control achieved in a Digital DBS TV? 07

*************

1


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – SUMMER • 2015

Subject Code: 171007 Date:06/05/2015 Subject Name: Satellite communication Time: 02.30pm-05.00pm Total Marks: 70 Instructions:


Q.1 (a) List the orbital elements and explain each of them in detail. Also give their significance in

orbital maintenance. 07

(b) Describe the earth’s oblateness, sun and moon’s effects on artificial satellite’s orbit? 07 Q.2 (a) A satellite is in an elliptical orbit with a perigee of 1000 km and an apogee of 4000 km.

using mean earth radius of 6378.14 km, find the period of the orbit in hours, minutes, and seconds, and the eccentricity of the orbit.

07

(b) List various types of control required to maintain the satellite in space and explain attitude and orbital control system in detail.

07

OR (b) List the types of parameter effective in downlink of satellite. Also give its significance and

arrange them in the equation for downlink. 07

Q.3 (a) What is the purpose of Telemetry, Tracking, Command, and Monitoring in satellite communication? Explain in detail.

07

(b) Give the list of all Multiple Access System used for satellite communication. Explain any one of them in detail and give comparison of any three.

07

OR Q.3 (a) An earth station situated in the U.K. needs to calculate the Look angles to a geostationary

satellite in the Indian ocean operated at INSAT. The details of the earth station site and the satellite are as follows: Earth station latitude and Longitude are 52.00 N and 00 Satellite longitude (subsatellite point) is 66.00 E

07

(b) The parameter that effect the selection of satellite launch vehicle. 07 Q.4 (a) List the types of propagation effect that can provide impact on satellite – earth link and

explain any two of them. 07

(b) An earth station have equivalent noise temperature of 2000 K, noise bandwidth of 18 MHz, antenna gain of 50dB and carrier frequency of 12 GHz Determine, Gain to Equivalent Noise temperature ratio, Noise density, and Total Noise Power.

07

OR Q.4 (a) Write short notes on Access Control Protocols used in VSAT network. 07

(b) What is GPS? Draw and explain the block diagram of the GPS receiver with all detail. 07 Q.5 (a) Write short notes on Master Control Station required for Direct Broadcast Satellite

Television (DBS-TV) system. 07

(b) Draw and Explain the block diagram of satellite transponder in detail. 07 OR

Q.5 (a) The uplink C/N0 ratio is 88 dBHz and downlink value is 78 dBHz. Calculate overall C/N0. 07

(b) Describe XPD. How XPD are predicted? Also Draw and Explain properly The Canting Angle and Tilt Angle with required equations.

07

*************

1/1


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – WINTER • 2014

Subject Code: 171007 Date: 29-11-2014


Time: 10:30 am - 01:00 pm Total Marks: 70 Instructions:




Q.1 (a) Explain different Satellite services. What is footprint? What is the

difference between polar orbit and geostationary orbit?

07

(b) Calculate the radius of a circular orbit for which the period is one day. 07

Q.2 (a) An earth station is located at latitude 30°S and longitude 130°E.

Calculate the antenna-look angles for a satellite at 156°E.

07

(b) Determine the angle of tilt required for a polar mount used with an

earth station at latitude 49° north. Assume a spherical earth of mean

radius 6371 km, and ignore earth-station altitude.

07

OR

(b) An antenna has a noise temperature of 35 K and is matched into a

receiver which has a noise temperature of 100 K. Calculate (i) the noise

power density and (ii) the noise power for a bandwidth of 36 MHz.

07

Q.3 (a) Write a short note on Equipment reliability and space qualification for

Satellite Communication.

07

(b) Draw and explain TT&C. 07

OR

Q.3 (a) Explain the block diagram of Satellite Transponder. Also explain the

frequency reuse technique for Transponder.

07

(b) Explain Cross-Polarization Discrimination. 07


(b) Explain Orbit Consideration with respect to Non-Geostationary

Satellite Orbit (NGSO).

07

OR

Q.4 (a) What is VSAT ? List the application of VSAT. Also Draw and explain

the architecture of VSAT system.

07



07


satellite link.

07

(b) Write differences between:

(i) Attitude control and orbital control

(ii) East west and north south station keeping maneuvers.

07

OR

Q.5

(a)

Explain the spade system.

07

(b) Explain GPS receiver operation in short. 07

*************

1


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – SUMMER • 2014



Time: 02:30 pm - 05:00 pm Total Marks: 70 Instructions:




Q.1 (a) What is satellite communication? Draw and explain the block diagram of

satellite communication in detail.

07

(b) By using of equation and figure properly explain the look angle determination

of satellite.

07

Q.2 (a) What are the specialties of satellite antenna? List the types of satellite antennas

used and explain any one of them.

07

(b) List the types of parameter effective in downlink of satellite. Also give its

significance and arrange them in the equation for downlink.

07

OR

(b) How we can provide C/N link design. Also combine C/N with C/I values in

satellite link.

07

Q.3 (a) List the types of Multiple Access Scheme used in the satellite communication

and give its comparisons.

07

(b) With the help of equation and block diagram Properly explain the Code

Division multiple Access in detail.

07

OR

Q.3 (a) List the types of propagation effect that can provide impact on satellite – earth

link and explain any two of them.

07

(b) List the types of orbits used in the satellite and give its comparison with

appropriate advantages and disadvantages.

07

Q.4 (a) What is VSAT? Draw and explain the block diagram of VSAT in detail. 07

(b) By using of appropriate equation and figure explain calculation of link margins

of VSAT for star network.

07

OR

Q.4 (a) Give and explain orbit, coverage and frequency consideration of non-

geostationary satellite system.

07

(b) Draw and explain the satellite mobile network in detail. 07

Q.5 (a) Draw and explain the Direct Broadcast satellite TV system in detail. 07

(b) Properly explain how error control mechanism works in the DBS-TV . 07

OR

Q.5 (a) What is GPS? Draw and explain the block diagram of the GPS receiver with all

detail

07

(b) Properly explain the principles of GPS location finding. Also explain Satellite

signal acquisition in detail.

07

*************

1/1


GUJARAT TECHNOLOGICAL UNIVERSITY BE - SEMESTER–VII • EXAMINATION – WINTER 2013



Time: 10:30 TO 01:00 Total Marks: 70 Instructions:




Q.1 (a) Explain different Satellite services. 07

(b) Explain the Keplerian element set. 07

Q.2 (a) Calculate the radius of a geostationary satellite. 07

(b) In a satellite link, thermal noise in an earth station results in a ratio of

25.0 dB. A signal is received from a transponder with a carrier to noise

ratio of 20.0 dB. Find the value of overall (C/N)o at the earth station.

07

OR

(b) Calculate the gain of a 3-m paraboloidal antenna with an aperture

efficiency of 0.55 operating at a frequency of 12 GHz.

07

Q.3 (a) Explain what is meant by satellite attitude and briefly describe two

forms of attitude Control.

07

(b) Draw and explain the TT&C. 07

OR

Q.3 (a) Give the list of all Multiple Access System used for satellite

communication. Explain any one of them in detail and give comparison

of any three.

07

(b) Explain what is XPD ? How XPD are predicted ? Also Draw and

Explain properly The Canting Angle and Tilt Angle with required

equations.

07


(b) Explain Orbit Consideration with respect to Non-Geostationary

Satellite Orbit (NGSO).

07

OR

Q.4 (a) Write short notes on Access Control Protocols used in VSAT network. 07



07


satellite link.

07

(b) Write short notes on GPS Receivers with using simplified block

diagram.

07

OR

Q.5 (a) What is GPS? Explain principle of GPS position location. Also

explain signal generation in GPS.

07

(b) Draw and Explain the block diagram of satellite transponder in detail. 07

*************

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