Page 179 - GSTL_14th May 2020_Vol 36_Part 2

2020 ] IN RE : NEW SPACE INDIA LTD. 281
pacity’ means any of the radio frequency transmission chan-
nels on the Serving Satellite through which DOS shall pro-
vide the Capacity to the user. The term Space Segment Ca-
pacity and Transponder Capacity are same and are often
used interchangeably. Generally, each transponder of
INSAT/GSAT Satellite(s) has 36 MHz of bandwidth capacity.
Based on the application and usage, customer demands for
particular bandwidth capacity in the transponder of a satel-
lite. This bandwidth capacity gets used by the customer for
uplink and downlink purposes.
(C) Parts of Communication Satellite :
A Communication Satellite has the following basic parts :
(i) Satellite Bus :
(a) Satellite Structure - This is the mechanical structure of the sat-
ellite on which various satellite sub-systems are integrated.
(b) Power System - This consists of Solar Panels as well as Batter-
ies to power the satellite.
(c) Antenna System - This is to receive/transmit signals between
earth stations.
(d) Command and Control System - This monitors the Satellite to
ensure that all vital operating parameters are working.
(e) Thermal System - This protects the satellite and its sub-system
from external environment.
(f) Propulsion System - This is used for station keeping and orbit
correction, to ensure that the satellite stays in its orbit.
(ii) Satellite Payload :
The payload of a communication satellite is Transponders. Tran-
sponder is an electronic part of the satellite that receives the signal
at a particular frequency, amplifies it and transmits it back to earth.
The transponder has the following parts :
(i) Band Pass Filters
(ii) Low Noise Amplifier
(iii) Mixer and Oscillator
(iv) High Power Amplifier
(a) The Band Pass Filter is a device that passes frequen-
cies within a certain range and rejects (attenuates)
frequencies outside that range.
(b) Low Noise Amplifier : - An electronic amplifier that
amplifies a very low power signal without signifi-
cantly degrading its signal-to-noise ratio. In general,
an amplifier increases the power of both the signal
and the noise present at its input. LNAs are designed
to minimize additional noise.
(c) Mixer : - An electronic system which converts the in-
put frequencies to output frequencies with the help
of oscillator frequency so as to avoid interference be-
tween uplink and downlink signals.
GST LAW TIMES  14th May 2020  179