Garmin GTS 855 - Manual (Page 10)

6 Garmin GTS 8XX Series Traffic Advisory System 190-00587-02 Rev. A
GTS 8XX Series Antenna Configurations
• Top only directional antenna.
• Top directional with bottom monopole antennas (recommended for fixed
gear aircraft) provides improved intruder visibility. The type of antenna used
will be primarily limited by the amount of space available on the bottom
of the airplane. Any aircraft that can utilize the directional antenna on the
bottom would benefit from its use.
• Top directional with bottom directional antennas (recommended for
retractable gear aircraft) provides benefit of intruder bearing visibility for
targets that are shaded from the top directional antenna.
GA 58 Directional Antenna
The GA 58 directional four element antenna is included with the basic GTS
system to provide altitude, distance, and bearing of threat aircraft. A single antenna
installation uses top-mounted placement. A second GA 58 may be bottom-
mounted to optimize coverage.
Figure 2 GA 58 Directional Antenna
Bottom Mounted Directional Antenna (optional)
A directional antenna may be used as an additional antenna for bottom-
mounting to reduce shading and provide altitude and distance of threat aircraft.
Interrogations from the bottom directional antenna are transmitted in an
omnidirectional pattern, but it still allows bearing determination from replies
received on the bottom antenna.