Product Manual

Table Of Contents
66
Precise Surveying - Field Applications & Concepts
The real height of the antenna is therefore the sum of the
vertical height and the phase center offset.
Measuring the vertical height only consists in measuring the
length of the range pole used to support the GNSS antenna
and the rover unit. As most range poles are height-adjustable
and have a graduation to set this height, measuring the
vertical height only consists in reading the graduation on the
pole.
If an Ashtech antenna is used, the system will automatically
determine the true antenna height because it has got all the
antenna parameters in its memory to perform the conversion.
For another antenna however, you will first have to create a
new antenna type in the system and enter its parameters (see
GNSS Antenna Features on page 62) in order to be sure the
system can accurately convert the vertical measurement into
real height.
Phase Center
Phase Center Offset
True
Antenna
Height
Vertical Height
Rover
Ground