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Z-Max Surveying System Operation and Applications Manual
Data Link
Data link is a general term that indicates that data is transmitted and received in some
way between two devices. In RTK surveying, the data link is the mechanism through
which the base and rover GPS receivers communicate over long distances. A robust
data link is a critical component of RTK systems. As explained earlier, the base GPS
receiver must transmit its raw data to the rover GPS receiver in order for the rover
GPS receiver to process the data and compute the vector between the base and
rover receiver in real-time. The base system transmits the data and the rover system
receives the data. Typical data links for mobile RTK systems are, UHF radio, VHF
radio and cellular modem.
Various different types of data links are available with the Z-Max RTK System.
Distance requirements, regional regulatory statutes, local interference and available
infrastructure will influence which data link to use.
Z-Max Communication Module
The Communication Module (Figure 2.5) is a flexible, modular platform designed
to house a variety of data links for real-time GPS. Depending upon the option you
have selected, the Communication Module may have a radio by itself, a cellular
modem by itself, or both a radio and a cellular modem. The Communication
Module connects directly to the Receiver GPS Receiver Module without cables.
Figure 2.5
Z-Max Communications Module
G3.book Page 164 Saturday, May 24, 2003 12:52 PM