Executing An Rtk Survey; Rtk Rover Initialization - ashtech Z-Xtreme System Manual

Executing an RTK Survey

Your ZX SuperStation is now ready to execute an RTK survey. With the rover system
in hand, you can now move about the project site locating features and/or staking out
points. The detailed steps for performing these tasks are very dependent on the field
application software being used. For this reason, the detailed steps required to per-
form these survey tasks will not be discussed here. This is best left to the documenta-
tion accompanying your field application software. Rather, some basic field
procedures will be presented that are universal to RTK surveying.

RTK Rover Initialization

Prior to performing any feature location or stakeout with the rover system, it must first
go through an initialization process. This initialization process had been given several
different terms: RTK Initialization, Ambiguity Resolution, On-The-Fly (OTF) Initializa-
tion, Fixing Integers, etc. All these terms refer to the same process.
Prior to initialization, the rover system is will compute positions at a degraded level of
accuracy. The accuracy prior to initialization could be anywhere from 0.15 meters (0.5
ft) to a couple meters. The initialization process is required to fine-tune the rover sys-
tem. Once initialized, the rover system will function at it's specified level of accuracy
until initialization is lost. Your field application software running on the handheld com-
puter will inform you of the current state of initialization and what accuracy level the
rover system is currently functioning at.
The initialization process is automatic. No interaction by the user is required to
instruct the rover system to initialize. When the rover system detects that it is not ini-
tialized, it will automatically execute the initialization process. The time required for
the rover system to complete the initialization process is very dependent on the condi-
tions at the survey site during the initialization process. If the survey site is free of
obstructions to satellite visibility and the system is observing at least 5 satellites, in
most cases initialization will be instantaneous, i.e. less than 5 seconds. The rover
receiver must be observing at least 5 satellites in order to initialize. If the survey site
is obstructed, causing the rover system to see less than 5 satellites, the system will
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