Calicut University 2006 B.Tech Electronics and Communications Engineering SATELLITE COMMUNICATION SYSTEMS - Question Paper

C 20277
EIGHTH SEMESTER B.TECH. (ENGINEERING) DEGREE
EXAMINATION, JUNE 2006
EC 2K 805 (E-SATELLITE COMMUNICATION SYSTEMS
(AI/EE/IC/PTEE 2K 803 E)
Time: 3 Hours
Maximum : 100 Marks

ans all ques.
Part A
1. (a) Explain the effect of radiation pressure on the satellite's orbit.

(b) What is meant by mean anomaly and actual anomaly ?

(c) Explain what is meant by station keeping of satellite.


(d) Explain why the low noise amplifier in a satellite receiving system is placed at the antenna
end of the feeder cable.

(e) Explain the factor that affect the uplink dmign in geostatiorury satellite communication.

(f) Explain what is meat: by equivalent isotropic radiated power.

(g) Explain the diserecce ranging from multiple weeas terhnigw and mulap;exug.

(h) Explain what is Aeint by frame efficiency in relation to TDMA operation. IP

(8x5=40marks)

Part B
2. (a) discuss as to how a satellite is placed into goostationary orbit from earth
Or
( b) , i -:x orbit for an earth orbiting satellite has an eccentricity of 0.15 and a semimajar axis
9,000 km. Determine (1) its periods time ; (2) the apogee height :(3) perigee height.
Assumes a mean value of 6371 km.. for the earth's radius.
(10 marks)
(ii, Explain what is meant by sun transit outage. (5 marks)

3. Oil i 1 Explain the function of thermal control system in a satellite. i t 3 marks)
ii Briefly discuss the 3 axis method of satellite stabilisation. (7 marks)

4. (a) (i) Derive carrier to noise ratio for combined uplink and downlink. (7 marks)
(ii) A multi-carrier satellite circuit operators is the 614 GHz band with subsequent
c .-
Uplink: Saturatiion flux density : - 67-5 dBW/Im.2
Input back-off 11 dB
Satellite GP ratio : - 11.6 dB K'=
Downlink : Satellite saturation EIRP : 264 dBW
Output back-off : six dB
Free space loss : 196.7 dB
Earth station GP ratio : 40,7 dB K-1
Ignore the other losses. compute the carrier-to-noise density ratio for combined links.
(8 marks)
or
(b) (i) Explain what is meant by noise factor ? For what source temperature is noise factor
described ?
5 marks)
(ii) Write short note on VSAI 7 marks)

5.(a).Explain the way in which demand assignment may be carried out in FDMA network.(8Marks)
(11).Explain what is meant by burst snychronisation in TDMA system(7 marks)
or
(b) Draw the block diagram CDMA transmitter and receiver and discuss. (15 marks)

(14 x 15 = 60 marks)

Earning:   Approval pending.