Question Paper: Satellite Communication & networks Question Paper - May 2017 - Electronics and Telecom Engineering (Semester 8) - Mumbai University (MU)
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## Satellite Communication & networks - May 2017

### MU Electronics and Telecom Engineering (Semester 8)

Total marks: --
Total time: --
INSTRUCTIONS
(1) Assume appropriate data and state your reasons
(2) Marks are given to the right of every question
(3) Draw neat diagrams wherever necessary

### Solve any five question from Q.1(a,b,c,d,e,f,g)

1(a) Why the 'Earth sensors' are not used for sensing the 'Yaw' axis in GEO satellites? 4 marks

1(b) Why a multi-beam antenna is used in satellite communication? 4 marks

1(c) For the same area of solar array which configuration spin stabilization or body stabilization, generate more power. Justify. 4 marks

1(d) Differentiate between window & frame organization. 4 marks

1(e) Why LNA in a satellite receiving system is placed at the antenna end of the feeder cable? 4 marks

1(f) Explain with diagram what is "Umbra" and "penumbra"? How it is affecting satellite operation? 4 marks

2(a) What are the different antenna tracking techniques of geostationary satellite? 4 marks

2(b) Discuss in detail Telemetry, tracking and command with necessary block diagram. 4 marks

3(a) What are the main consideration in the design of an earth station? And how the earth stations are classified? 4 marks

3(b) Explain the need of placing LNA next to Antenna, Calculate over all C/N Ratio for satellite if [C/N], uplink = 25db & [C/N], downlink = 20 db Intermodulation Noise =12db 4 marks

4(a) Discuss Design Consideration of Earth station, Draw the block diagram for Transmit and receive earth station and explain. 4 marks

4(b) Compare Pre assigned FDMA and Demand assigned FDMA. 4 marks

4(c) Explain TDMA frame structure. 4 marks

5(a) Explain on board connectivity with Transparent processing. 4 marks

5(b) Discuss OST Model for satellites Network also discuss layering principle. 4 marks

5(c) Why TWT amplifier is Preferred for satellite communication? 4 marks

### Solve any five question from Q.1(a, b, c,d,e)

6(a) Optical satellite Transmitter and receiver 4 marks

6(b) Comparison of DS-CDMA, FH-CDMA and TH-CDMA. 4 marks

6(c) Launching Mechanism 4 marks

6(d) Reliablity and space qualification test 4 marks

6(e) VSAT 4 marks