antenna phase center question

hello,

for calculation of the phase center of an antenna an elevation range is specified. what is the most common range for commercial gps antennas? is a different range used for chip based antennas, rover antennas, geodetic antennas (choke ring)? can anyone give some real life examples, application notes, antenna datasheets, or any other valuable document?

thank you.
best regards.

This is a case where the same words have different meaning.
RF people and on the Telecommunication market, the phase center is a concept rather than a real point. It's the point, along the axis where you observe the smaller phase variation when you are measuring the pattern.
Horns may have different phase center for small angle E scan, small angle H scan, wide angle E scan, wide angle H scan.
But usually the difference are small enough to be contained into the focal cloud.
Also, for large dishes, placing an illuminator with it's phase center coincident with dish foci, will get the maximum efficiency.

Different is the geodetic concept.
The phase center is always marked on the most expensive GPS, ring antennas.
In this case the phase center is the reference point for geodethic measuremet and is traceable (may be collimated) with optical instruments like theodolite.