Archive for July 24th, 2009

GPS antennas and positioning

July 24th, 2009 by Ricardo PĂ­riz

In GPS antennas, there are three important reference points that have to be considered, as shown in the following picture (borrowed from NRCan):

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The Antenna Phase Center (APC) is the virtual electronic point that actually tracks the GPS signals. In principle, coordinates from any GPS receiver or station refer to this point.

However, for geodetic applications, since the antenna might be replaced by another model at some time, it is important to consider a physical point attached to the ground. This is called the Marker. (more…)