ashtech DG14, Справочное руководство

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Coordinate Transformation 83
Coordinate T
ransformation
Convert geodetic coordinates into grid coordinates by defining a grid system utilizing
one of the supported projection types (Figures 5.2 - 5.6).
To set the receiver to supply grid coordinates:
1. Select the projection type that best fits your needs.
2. Define the grid system, using this projection type, with the
$PASHS,UDG
command. This command defines the grid system to be used.
3. Enable the grid system with the $PASHS,GRD,UDG command. The receiver
computes grid coordinates in the system defined.
4. To access the grid coordinates, use either the $PASHQ,GDC command to
query for one output of the current coordinates, or use the
$PASHS,NME,GDC command to set the receiver to continuously output the
current coordinates.
There is one exception when configuring the receiver to compute and output grid
coordinates. If you are interested in computing and outputting WGS-84 based UTM
coordinates, there is no need to define the grid system in the receiver. The
parameters for WGS-84 UTM are pre-set in the receiver. To use them, set the
receiver to output grid coordinates using either the
$PASHQ,UTM command to
query for one output of the current coordinates, or the $PASHS,NME,UTM
command to set the receiver to continuously output the current coordinates.
Check the GDC message for the currently assigned datum.
CAUTION
Although almost any projection or combination of datums and projections
is mathematically possible, some are inappropriate with respect to the
project scope or geographic area.