POS MV V4 User Guide
Fault Identification
Copyright © Applanix Corporation, 2009
9-20
GNSS
The GNSS subsystem can experience a permanent loss of satellites,
or a breakdown of communication between the GNSS receiver and
the PCS.
Permanent Loss of Satellites
POS MV provides continuous information on the status of the GNSS
receivers. The status of the GNSS receivers may be monitored on the
GNSS Data window; select V
iew, GNSS Data from the MV-POSView
menu bar. Additionally, the GNSS Data window includes detailed
information on the satellites that the receiver is tracking and on the
receiver mode (i.e. tracking, navigate, etc).
The GNSS subsystem may experience periodic GNSS dropouts
caused, for example, by antenna obstruction. The controller program
indicates a GNSS dropout by displaying GNSS Not Available or
GNSS Data Gap in the GNSS Status field on the main window.
However, if a GNSS dropout occurs and persists without any
apparent antenna obstruction, then one of the following problems may
exist:
• A loss of GNSS receiver configuration
• A failure in the GNSS antenna
• A failure in the GNSS antenna cable
• A failure in the GNSS receiver
The above diagnoses assume that the PCS continues to receive
messages from the primary GNSS receiver. If this is true, the front
panel GNSS light will behave normally for the GNSS service in use.
If the front panel GNSS light shows red, then there are no GNSS
navigation solutions available to the PCS. The most likely cause of
this is a loss of communication with the receiver. If this occurs, refer to
the following Loss of Communications heading.
To Next Page
