Spectra Precision ProMark 800 Reference Manual - Manual (Page 62)

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Precise Surveying - Field Applications & Concepts
Integer Ambiguity: “Integer” refers to the number of entire
wavelengths of signal carrier separating a satellite from a
receiver. “Ambiguity” refers to the fact that this number is
unknown at the beginning of a survey. Solving integer
ambiguity therefore means determining the exact number of
entire wavelengths.
Other General
Considerations
RTK Real-Time vs. Post-Processing
In real-time surveys, system initialization is achieved when
the system has been able to fix an RTK solution for any new
position it computes. You just have to make sure this
operating status is maintained until the end of the survey. In
real time, it is therefore quite natural that you make sure the
initialization process has been successful. Should you lose
the “RTK” position status, then the system has lost
initialization and you should act to restore it.
In post-processed surveys, there is the same need for
initialization except that the system is not always able to
inform you, in real time, that this requirement is met.
Remember that in this type of survey, your system is just a
raw data collector.
It is only subsequently, when back at the office to post-
process the raw data that you will see if the complete set of
collected data results in successful and sustained
initialization.
Kinematic vs. Static
In static surveys, the risk of unsuccessful initialization is
significantly lessened by the fact that the GNSS antenna is
motionless and the system is operated for relatively long
recording sessions with the best possible view of the sky.
This may not be true for kinematic surveys during which the
rover is moved from place to place, with real risks of:
• Masking the GNSS antenna causing lock on satellites to
be lost.
Good distribution
of satellites in space
Excellent GDOP
(0
Poor distribution
of satellites in space
Poor GDOP
(PDOP>5)
Your GNSS antenna