Site considerations
98-175666-A
Chapter 2: Installation
2-17
Interference from radar, GPS/GNSS receivers, L-band antenna and other
transmitters
Even at distances greater than “d min.” in the previous section the radar might still be able
to degrade the performance of the SAILOR XTR Ka system. The presence of one or more S
or X-band radars within a radius up to 100 m may cause a minor degradation of the Ka band
connection. The degradation will be most significant at high radar pulse repetition rates.
As long as receiving conditions are favorable, this limited degradation is not important.
However, if receiving conditions are poor – e.g. due to objects blocking the signal path,
heavy rainfall or icing, low satellite elevation and violent ship movements – the small extra
degradation due to the radar(s) could cause poor connection quality. The presence of S-
band radar(s) is unlikely to cause any performance degradation – as long as the minimum
distances (d min.) listed in the previous section are applied.
It is strongly recommended that interference-free operation is verified before
the installation is finalized.
Good quality GPS/GNSS receivers will work properly very close to the ADU - typically down
to one meter outside the main beam.
X-band (~ 3 cm / 10 GHz) damage distance
Radar
power
SAILOR XTR Ka ADU
d min. at 15° vertical
separation
d min. at 60° vertical separation
0 – 10 kW
1.0 m
1.0 m
30 kW
2.0 m
1.0 m
50 kW
3.3 m
1.7 m
Table 2-9: Minimum radar separation, X-band
S-band (~ 10 cm / 3 GHz) damage distance
Radar
power
SAILOR XTR Ka ADU
d min. at 15° vertical
separation
d min. at 60° vertical
separation
0 – 10 kW
2.0 m
1.0 m
30 kW
3.0 m
1.5 m
50 kW
5.0 m
2.5 m
Table 2-10: Minimum radar separation, S-band
CAUTION!
Never install the antenna closer to a radar than “d min.” - even
if experiments show that interference free operation can be
obtained at shorter distances than “d min.” in the previous
section.
