APPENDIX G Importance of Antenna Selection
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Figure 144: Plot of Good and Poor Antenna Phase Center Variation over Elevation Angle 0-90°
Many users can accept accuracies of less than a meter so these small phase center variations cause a neg-
ligible amount of position error. But if you require high precision, Real Time Kinematic (RTK) receivers can
achieve position accuracies of 2-4 cm and a few millimeters of phase center error translates to a 10-15%
error in reported position. For RTK survey applications, geodetic grade antennas offer superior PCO/PCV
performance.
6. The application
An antenna has to meet the performance, environmental, mechanical, and operational requirements of the
intended application. For example, GNSS antennas used for aviation applications should ideally be
TSO/FAA certified and be rugged enough to handle extreme temperatures and vibration profiles. Survey
rover antennas should be able to survive rough handling by surveyors including a pole drop.
The table below highlights some of the important desirable features needed for a GNSS antenna based upon
the user’s application.
