Spectra Precision ProMark 800 Reference Manual - Manual (Page 61)

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Precise Surveying - Field Applications & Concepts
better than 30 meters (probably closer to 10-20 meters),
but an error of 50 meters is possible.
If you plan to use an estimated position for the base, keep
the vector lengths between the base and rover short and
ensure the added error is not significant for the survey you
are performing.
Initialization
Preamble Initialization (also known as “ambiguity fixing”, “integer
fixing” or just “fixing”) is the process through which your
real-time receiver or post-processing software can solve the
integer ambiguity inherent in the carrier phase processing.
Solving for the integer ambiguities is a prerequisite for the
receiver or software to be able to deliver centimeter-accurate
positions.
For this reason, initialization is a requirement you should
constantly keep in mind.
NOTE: This initialization process should not be confused with
the initialization of a GNSS receiver, corresponding to the
start sequence during which the receiver searches for the
visible satellites in order to be able to compute its first
standalone 5- to 10-meter-accurate position.
Importance of
Baseline Length
The amount of data required to fix ambiguities in the software
(post-processing) or the rover (RTK real-time) is proportional
to the baseline length.
In other words, the longer the baseline length, the longer the
time required to achieve initialization.
Key Terms and
Expressions
DOP: Dilution of Precision. A factor computed by the
equipment that describes satellite distribution in space. The
lower the DOP, the better the distribution in space and the
better the probability of a successful survey. Several DOP
values exist, such as the GDOP, HDOP, VDOP, TDOP, but the
most frequently used one is the PDOP (for Position Dilution
of Precision).