ZED-F9P - Integration manual
Figure 63: Stacked patch antenna
The absolute antenna position for a survey-grade antenna is normally given as the antenna
reference point (ARP), usually specified at a mechanical mounting point. The antenna nominal phase
center is given by a phase center combination of the L1 and L2 patches. Survey-grade antenna
makers provide offset data for phase variation with respect to the ARP.
Figure 64: Ceramic stack
When used in an application, the antenna placement affects the phase center variation owing to
the size and shape of the ground plane coupled with the effects of the adjacent structures. A phase
center variation calibration is required to check the average phase center. A successful calibration
can be made if the phase variation of a specific antenna is repeatable between samples.
To obtain the best antenna performance in an automotive application, mount the antenna in the
center of a conductive car roof without any inclination. The antenna requires good signal levels and
as wide a view of the sky as possible. The antenna must not be placed under a dashboard, in the rear
view mirror, or on the rear parcel shelf.
UBX-18010802 - R08
Appendix
Page 105 of 110
Early production information