WinFrog User’s Guide - Appendix C – GPS/MX 9400
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Accuracy:
The Accuracy value entered provides WinFrog with the expected accuracy of the
position from this device. This value is used in the weighting of this device compared
to other positioning devices that may be added to the vehicle’s device list. The
smaller the value entered, the more accurate it is considered to be, and hence the
more weight that will be applied to the device’s data. The Accuracy parameter can
be changed from the suggested values, although changes should be made with
caution, as they will affect the final filtered position of the vehicle.
The Velocity value is used in positional filtering. The lower the value entered, the
more smoothing that is applied.
Remote Unit ID:
The Remote Station ID parameter is set to zero (0) unless the GPS device is
interfaced to WinFrog via a telemetry device.
Antenna Height:
Set the Antenna Height using the radio buttons and the (input) Ellipsoid Height field.
Settings are as follows:
Calculated
–
Select this option to force WinFrog to calculate the GPS antenna
Height as well as its Latitude and Longitude. In this mode, WinFrog requires a
minimum of four satellites to be visible.
Fixed
– Select this option to fix the GPS antenna ellipsoid height to the value
entered in the
Ellipsoid Height
field. In this mode, WinFrog is able to calculate
valid positions using a minimum of three satellites.
Auto\Last Height
– If this mode is selected, WinFrog will calculate a 3D position
if four or more satellites are available. If only three satellites are visible, or if the
VDOP of the solution exceeds the value set in the Alarms dialog box,
the height
is fixed to that of the last valid position. In this mode WinFrog is able to calculate
valid positions using a minimum of three satellites.
Auto\Input Height
– If this mode is selected, WinFrog will calculate a valid 3D
position if four or more satellites are available. If only three satellites are
available, or if the VDOP of the solution exceeds the value set in the Alarms
dialog box, the height is fixed to the value entered in the
Ellipsoid Height
field.
In this mode, WinFrog is able to calculate valid positions using a minimum of
three satellites.
Note
:
The Antenna height entered in the
Pseudorange Calculation
dialog box
refers to the WGS 84 Ellipsoid.
Offsets:
Offsets are entered to relate the GPS antenna position to the vessel’s Common
Reference Point (CRP). Offsets are entered as measured from the CRP (of the