Figure 2.1 Ashtech Z-Xtreme Gps Receiver - ashtech Z-Xtreme System Manual

Figure 2.1 Ashtech Z-Xtreme GPS Receiver

The ZX SuperStation is built around the Z-Xtreme dual-frequency GPS receiver. The
Z-Xtreme supports an integral battery, removable PC card memory, and optional inter-
nal radio. It is capable of functioning as the base or rover in RTK and post-processed
surveys. The integrated display and control panel supports the ability to perform
some survey tasks without a handheld computer. Environmentally, the receiver meets
MIL-STD-810E specifications for wind-driven rain and dust.
In order for the GPS receiver to receive satellite signals, it must utilize an antenna.
The GPS receiver antenna is the actual collection point of the satellite signals. It is
also the point for which the position of the rover system is computed. Therefore, to
determine the location of a feature, the GPS receiver antenna must be placed over
this feature. The horizontal position of the feature is determined by the location of the
center of the antenna. The vertical position of the feature is determined by the loca-
tion of the center of the antenna minus the known height of the antenna above the
feature. Each GPS receiver in the system has one GPS receiver antenna. The ZX
SuperStation offers a choice between two different GPS receiver antennae for the
base system: the Geodetic IV antenna and the Choke Ring antenna. Obstruction con-
ditions at the base position will dictate which antenna is appropriate.
8 Real-Time Kinematic Surveying