### EC 1403 SATELLITE COMMUNICATION Questions Bank 2014

Anna University, Chennai

DEPARTMENT OF ECE QUESTION BANK

SUBJECT CODE: EC 1403

SUBJECT NAME: SATELLITE COMMUNICATION

Prepared by

P.P.Selvakumar, M.Rekha

PAR T - B (16 Marks) UNIT- 1

1. Describe the terms of Earth orbiting satellites.

*Apogee: The point farthest from earth.

*Perigee: The point closest approach to earth

*Ascending node: The point where the orbit crosses the equatorial plane going from south to north.

*Descending node: The point where the orbit crosses the equatorial plane going from north to south.

*Line of nodes: The line joining the ascending & descending node through the center of the

earth.

*Line of apsides: The line joining the perigee & apogee through the center of the earth.

*Inclination: The angle between the orbital plane & the earth’ s equatorial plane.

*Prograde orbit: An orbit in which the satellite moves in the same direction as the earth’ s

rotation.

*Retrograde orbit: An orbit in which the satellite moves in a direction counter to the

earth’ s rotation.

*Argument of perigee: The angle from ascending node to perigee, measured in the orbital plane

at the earth’ s center in the direction of satellite motion.

2. Explain the orbital p lane. Draw it neat sketch i) Diagram:

ii) Explanation:

*In the orbital plane, the position vector ‘r’ & the velocity vector ‘v’ specify the motion

of satellite.

R=a(1-e2)/1+ecosv

*Mean anomaly M at time t is found

M=n (t-T) VºM+2esinM+5/4e2sin2M.

3. Explain the Orbital perturbations.

Explanation:

*Effect of non-spherical earth

*Atmospheric drag

*Inclined orbits

*Calendars

*Universal time

*Julian dates

*Sidereal time

4.Explain the geocentric equatorial &top centric co-ordinate system.

· Diagram:

· Explanation:

5.Explain the sub satellite point i) Diagram

ii) Explanation:

UNIT – 2

6. Explain the look angle determination. Draw it neat sketch. i) Diagram:

ii) Explanation:

7. Explain the polar mount antenna. Draw it neat sketch. i) Diagram:

ii) Explanation:

8. Explain the limits of visibility & sun transit outage. i) Diagram:

ii) Explanation:

9.Explain the attitude control. Draw it neat sketch. i) Diagram:

ii) Explanation:

10. Explain the Transponders system. i) Diagram:

ii) Explanation:

*Transponder

11.Draw the neat sketch & explain the Input Demultiplexer. i) Diagram:

ii) Explanation:

UNIT – 3

12. Draw the neat sketch & explain the Antenna subsystem. i) Diagram:

iii) Explanation:

13. Draw the block diagram & explain the Receive only home TV systems. i) Diagram:

ii) Explanation:

14. Explain the indoor unit& outdoor unit. i) Diagram:

ii) Explanation:

15. Draw the block diagram & explain the Master antenna TV system. i) Diagram:

ii) Explanation:

*Community antenna TV system

16. Explain the EIRP & Transmission losses.

*EIRP=GPs

*EIRP is often expressed in db is given by

EIRP=(Ps)+(G) Dbw. Transmission losses:

· Free space transmission

· Feeder losses

· Antenna misalignment losses

· F ixed atmospheric & ionospheric losses

17. Draw the block diagram& Explain the S ys tem noise temperature. i) Block Diagram

ii) Explanation:

*System noise

*Antenna noise

*Amplifier noise temperature

*Noise factor

*Noise temperature of absorptive networks.

18. Explain the carrier to noise ratio of uplink & downlink frequency.

19. Explain the Inter-modulation noise & saturation flux density.

UNIT -4

20. Explain the operation of F DMA system with relevant diagram. i) Diagram

ii) Explanation

*Preassigned F DMA

*Demand assigned F DMA

21. Explain the operation of F DMA down link analysis. i) Diagram

ii) Explanation

22. Draw the Frame format & explain the operation of TDMA system. i) Diagram

ii) Explanation

Reference burst

*Guard time

*Carrier & bit timing recovery

*Burst code word

*Station identification code

*TTY

*Service channel

23.Draw the data format & explain the Unique word detection. i) Diagram

ii) Explanation

*Miss probability

*False detection probability

24. Explain the Satellite switched TDMA & C DMA. Draw the neat sketch. i) Diagram

ii) Explanation

UNIT – 5

25. Explain the Radar sat & MS AT. Mention the applications.

26. Expla in about Water resource applications using GIS.

27. Explain about Urban applications using GIS.

28. What is Map? Explain its types

29. Analyze the raster and vector data by retrieval, reclassification, Overlaying and buffering in GIS

30. Explain about data input & output hardware of GIS.