Spectra Precision Survey Pro v3.80 Recon GPS User Manual - Manual (Page 47)

RTK Data Collection
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Localization Parameters Explained
Before you accept a localization solution, you should evaluate the
parameters and the quality of the solution. This section describes the
meaning and the expected values for the six horizontal and five
vertical localization parameters. Guidelines for the quality and
geometry of control points plus the solution redundancy and residuals
are also described.
Ground - TDS Localization Mode:
Scale: is the scale difference between the intermediate
mapping plane and the local system. Scale should be
very close to 1.0. A value of 1.0 corresponds to ground
level distances at the base reference height.
Scale values are often reduced to parts per million in
order to relate the factor to a distance. One ppm (the
sixth decimal place ie. 1.000001 or 0.999999) is equal to
1mm in 1km; this is well below RTK precision. Fifteen
ppm (1.000015 or 0.0.999985) is equal to 15mm in 1km;
this is a usual RTK precision, so anything in this range
is expected. A scale value significantly greater or
smaller than 1.0 may indicate problems with the control
point accuracy and/or the control measurement precision.
It might also indicate a base reference height too high or
low for the survey area, or a scale bias in the control
point local coordinates.
Rotation: is the rotation between the Localization map projection
zone and the local system. The rotation represents the difference
between grid north and geodetic north at the meridian passing
through the origin of the Localization transformation.
Origin: is the coordinate on the intermediate mapping plane of the
centroid of the control points. It is calculated by average of (N,E)
coordinate of all control points.
Translation: is the shift between the origin and the local coordinate
of the centroid of the control points