User’s Manual
7
In Table 1 below, the SFD values are presented for the above mentioned gain settings and for
each particular satellite antenna.
The quoted figures, based on the less sensitive transponder at nominal configuration,
represent average values for all transponders. This means that a difference of 1 or 2 dB from
the specified values is expected. Moreover, the peak gain values correspond to the minimum
available values. However, the quoted figures can be used in link budget calculations for
planning purposes.
A simplified link budget example is presented in Annex A to show how IPFD for saturation is
employed in link budget calculations.
Gain
Step
F1 antenna
F2 antenna
S1 antenna
S2 antenna
Peak
Gain
+8.37 dB/K
Satellite
Contour
0 dB/K
Peak Gain
+11.10
dB/K
Satellite
Contour
0 dB/K
Peak Gain
+5.94 dB/K
Satellite
Contour
0 dB/K
Peak Gain
+5.65
dB/K
Satellite
Contour
0 dB/K
5(L)
-82.20 -73.83
-84.9 -73.80
-80.90 -74.96
-76.80 -71.15
9(M)
-88.32 -79.95
-91.12 -80.02
-87.16 -81.22
-82.95 -77.3
13(H)
-94.66 -86.29
-97.37 -86.27
-93.44 -87.50
-89.16 -83.51
Table 1: Average SFD values for transponder saturation versus sensitivity
Using values from Table 1 and the G/T maps it is easy to calculate the SFD on a specific
location. The required SFD calculation formula is shown below.
SFD calculation formula:
)
/
/
(
_
L
Peak
Peak
L
Peak
L
T
G
T
G
SFD
SFD
Correction
Aspect
SFD
SFD
−
+
=
⇒
+
=
(Equation
1)
An appropriate example for the calculation of the SFD and all necessary parameters for a link
budget can be seen in Annex C.
1.6
Β
EACONS
A Ku- band beacon generator on board of the satellite provides a signal to a dedicated global
horn antenna. The Ku-band beacon transmits a single right hand circular polarized
unmodulated frequency of 11.4515 GHz with a maximum EIRP of 12 dBW within the whole
visible area from the satellite. A 3 dB loss of power level is expected if linear polarization
reception system is used by the station. This beacon is a two for one redundant unit and is
used by the earth stations operators to track the Hellas-Sat 2 satellite.
