Regarding the selection of a suitable
antenna location
, the following recommendations
generally apply:
A
clear view of the sky down to the horizon
in all directions is recommended
for the most optimal satellite reception. The mounting location of the external
GNSS antenna should be free of objects that could obstruct satellite visibility
from straight overhead to within 20 degrees of the horizon in all directions.
To optimize timing accuracy, the GNSS receiver attempts to track satellites that
are spread out as far as possible across the sky. The GNSS receiver must track at
least four satellites in order to obtain time synchronization. Obstructions that
block a significant portion of the sky result in degraded performance.
GPS antennas need to be separated from surrounding
metallic materials
. Any
metal in the area changes the shape of the reception pattern of the antenna. Any
buildings or metallic materials close to the antenna can create shadows which can
shield the antenna from receiving in that particular direction.
Separation between multiple antennas
: If the antennas are installed too close
together there could potentially be interaction between the antennas and a res-
ulting loss of sensitivity. This could also adversely affect the search pattern of the
antennas, resulting in fewer satellites being tracked.
Ideally, antennas should be separated as much as physically possible, so as
to help isolate them from being simultaneously affected by the same anom-
aly (such as a nearby lightning strike or a falling object, for example). The
minimum GNSS antenna-to-antenna distance is 39 inches (1 meter).
GPS antennas are receive-only antennas which do not intentionally trans-
mit any signals. Even though this reduces the amount of separation needed
between multiple antennas, a few meters of separation are recommended
to isolate the antennas from each other, in order to limit any possible EMI
interference caused by the active components inside the antennas.
236
VelaSync User's Manual
APPENDIX
Summary of Contents for VelaSync 1225
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Page 12: ...BLANK PAGE X VelaSync User s Manual TABLE OF CONTENTS...
Page 28: ...16 CHAPTER 1 VelaSync User s Manual Rev 3 1 7 The VelaSync Web UI...
Page 34: ...BLANK PAGE 1 9 Regulatory Compliance 22 CHAPTER 1 VelaSync User s Manual Rev 3...
Page 104: ...BLANK PAGE 2 11 Configuring PTP 92 CHAPTER 2 VelaSync User s Manual Rev 3...
Page 251: ...Server management System specifications VelaSync User s Manual 239 APPENDIX...
Page 267: ...VelaSync User s Manual 255 APPENDIX...