POS MV V5 Installation and Operation Guide
System
Configuration
4-26
page 4-23) and write down the displayed parameters. Keep the written record in a safe place for
future reference.
Refer to the Operation with GAMS topic on page 1-8 for a description of how GAMS uses the GAMS
installation parameters to aid the On-the-Fly (OTF) ambiguity search.
Installation Parameter Correction
The surveyed antenna baseline vector may include the following errors:
•
The length of the vector may not be correct if there were large multipath errors during the
calibration process. This may affect the reliability of the GAMS ambiguity resolution during future
POS MV Initialization sequences.
•
There may be an azimuth error similar in size to the displayed heading accuracy that existed
during the calibration process. This results in a constant offset in the displayed heading during
normal operation of the POS MV with GAMS heading aiding.
Correct these errors by:
1. If the displayed antenna separation differs by more than 5 mm (~¼ in) from the value that you
measured after you installed the antennas, clear the installation parameters and then re-enter the
measured
separation distance in the
GAMS Parameter Setup
window, see Figure 34: POSView
GAMS Parameters Setup on page 4-23. Select the
OK
button
to install the new antenna
separation distance.
Begin a new calibration procedure, see Antenna Installation Calibration on page 4-21.
The 5 mm (~¼ in) allowance accounts for differences that may exist between the antenna phase
centres and their geometric centres.
2. If you can identify a heading offset then enter this value in the
Heading Correction
field of the
GAMS Parameter Setup
window, see Figure 34: POSView GAMS Parameters Setup on page
4-23. Select the
OK
button
to install the new correction value.
POS MV will then compute new components of the surveyed antenna baseline vector having a
corrected azimuth.
3. Select
Settings, Save Settings
from the MV-POSView menu bar to save the new values to the
PCS Non-Volatile Memory (NVM).
Note:
The
Heading Correction
field in the
GAMS Parameter Setup
window allows you to correct an
inaccurately surveyed baseline vector. You can use this method to obtain a more accurate vector.
Note:
You should
not
use this facility to implement the installation angles of the IMU body frame with
respect to the echo-sonar frame. Refer to the Installation Parameters and the Configuration Data