EC 1403 SATELLITE COMMUNICATION
SEMESTER VII
Overview of satellite systems, orbits and
launching methods
• Introduction – Frequency allocations for satellite services –
Intelsat – U.S domsats – Polar orbiting satellites – Problems –
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 – Orbital
perturbations – Effects of a non-spherical earth –
Atmospheric drag – Inclined orbits – Calendars – Universal
time – Julian dates – Sidereal time – The orbital plane – The
geocentric – Equatorial coordinate system – Earth station
referred to the IJK frame – The topcentric – Horizon coordinate system – The subsatellite point – Predicting satellite
position.
Geostationary Orbit And Space Segment
• Introduction – Antenna look angles – The polar mount antenna – Limits of
visibility – Near geostationary orbits – Earth eclipse of satellite – Sun
transit outage – Launching orbits – Problems – Power supply – Attitude
control – Spinning satellite stabilization – Momentum wheel stabilization –
Station keeping – Thermal control – TT&C subsystem – Transponders –
Wide band receiver – Input demultiplexer – Power amplifier – Antenna
subsystem – Morelos-anik – E-advanced tiros – N spacecraft
Earth Segment And Space Link
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Introduction – Receive – Only home TV systems – Outdoor unit – Indoor unit for
analog (FM) TV – Master antenna TV system – Community antenna TV system –
Transmit – Receive earth stations – Problems – Equivalent isotropic radiated
power – Transmission losses – Free-space transmission – Feeder losses –
Antenna misalignment losses – Fixed atmospheric and ionospheric losses – Link
power budget equation – System noise – Antenna noise – Amplifier noise
temperature – Amplifiers in cascade – Noise factor – Noise temperature of
absorptive networks – Overall system noise temperature – Carrier to- Noise
ratio – Uplink – Saturation flux density – Input back off – The earth station HPA
– Downlink – Output back off – Satellite TWTA output – Effects of rain – Uplink
rain– Fade margin – Downlink rain – Fade margin – Combined uplink and
downlink C/N ratio – Inter modulation noise.
UNIT IV
Satellite Access
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Single access – Preassigned FDMA, Demand assigned FDMA, SPADE system.bandwidth –
Limited power – Limited TWT amplifier operation, FDMA downlink analysis.
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TDMA: Reference burst – Preamble and post amble – Carrier recovery – Network
synchronization – Unique word detection – Traffic date – Frame efficiency and channel capacity –
Preassigned TDMA – Demand assigned TDMA – Speech interpolation and prediction –
Downlink analysis for digital transmission – Calculation of uplink power requirements for FDMA
and TDMA – On-board signal processing for TDMA / FDMA operation – Satellite switched
TDMA
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Code Division Multiple Access – Direct sequence spread spectrum – Code Signal C(T) –
Autocorrelation function for C(T) – Acquisition and tracking – Spectrum spreading and
despreading – CDMA throughput – Problems – Network layers – TCP link – Satellite links and
TCP – Enhancing TCP over satellite channels using standard mechanisms (RFC– 2488) – Requests
for comments – Split TCP connections – Asymmetric channels – Proposed systems – Direct
broadcast satellite services.
Geographic Information System
• GIS – Components of GIS – Hardware, software and organisational
context – Data – Spatial and Non-spatial – Maps – Types of maps –Visual
interpretation of satellite images – Elements of interpretation –
Interpretation keys characteristics of digital satellite image – Image
enhancement – Filtering – Classification – Integration of GIS and remote
sensing – Urban applications – Application of remote sensing and GIS –
Water resources – Urban analysis – Watershed management –
Resources information systems. Global Positioning System (GPS) – An
introduction.
Image Filtering
TEXT BOOKS
• Dennis Roddy, “Satellite Communications”, 3rd
Edition, TMH Publication, 2001
• Anji Reddy, “Remote Sensing and Geographical
Information Systems”, BS Publications, 2001.
ASSIGNMENTS
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KEPLER’S LAWS
CO-ORDINATE SYSTEMS
TRANSPONDERS
TRANSMISSION LOSSES
TDMA
FDMA
GPS
SEMINAR TOPICS
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GEOSTATIONARY SATELLITES
DTH
REMOTE SENSING
GIS
GPS
URL’S
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http://www.odyseus.nildram.co.uk/Systems_And_Devices_Files/Sat_Comms.pdf
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http://www.aticourses.com/iridium.htm
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http://www.aticourses.com/global_positioning_system.htm
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http://www.palowireless.com/satellite/tutorials.asp
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http://www.gatewayforindia.com/technology/satellite.htm
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http://www.crisp.nus.edu.sg/~research/tutorial/intro.htm
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http://www.radio-electronics.com/info/satellite/communications_satellite/satellitecommunications-basics-tutorial.php