Spectra Precision Survey Pro CE v3.60 GPS User Manual - Manual (Page 45)

RTK Data Collection
41
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