Seatex DPS 200 - Gyro Interface; Offset Vectors (or Lever Arms); Offsets in Reference Station Co-Ordinates

Seatex DPS 200 Installation Manual, rev. 4 Installation
40
correctly in a multireference solution, a different weight than other DGPS corrections is
required.
DCLNK1 IONOSPHERE COMPENSATED 0 ! 0: Not corrected, 1: Corrected
This line indicates that the differential link connected to the DCLNK1 (Differential Correction
Link 1) port is of a type where ionosphere error contributions, both at reference station and at
mobile station, have been compensated. Data from this type of links need special treatment in
the software weight algorithms.
3.9.12 Offsets in reference station co-ordinates
Corrections distributed from some reference stations are based on a different geographical
datum than WGS 84, which is used by the GPS satellites. The position error at these reference
stations will lead to an equivalent error in the mobile position. A feature for compensation of
errors in DGPS reference station co-ordinates is implemented.
DCLNK1 REF STATION OFFSET 0.0 0.0 0.0 ! Reference station position error/offset
This line makes it possible to correct for position errors/offsets in reference stations' positions
for stations received on DCLNK1. The offsets, in meters, are respectively north/south,
east/west and height from WGS 84 to offset. Positive north and east.
The offset is applied for all stations received on the correction link. The operator must know
the reference position offsets to use the additional settings.
3.9.13 Gyro interface
Heading input from a gyrocompass can be used to display heading and speed on the TMS
display. In addition, heading is necessary in order to utilise the built-in lever arm
compensation.
GYROIO_1 TYPE NMEA_HDT
Two types of heading formats are accepted by the DPS system, the NMEA heading format,
HEHDT, and the Robertson LR22 BCD format, LR22_BCD.
3.9.14 Offset vectors (or lever arms)
The offset vectors (or lever arms) are defined from the given position to the point related to a
right hand system (positive forwards, to starboard and down).
Lever arm selections indicated in the TMS display will only affect the distance and bearing
figures in the TMS display. The figures sent out from the system are not affected by operator
selections.
FSP ref.: A11213500XRBRA0