Sperry Marine Visionmaster FT ECDIS, User Manual

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ECDIS User Guide Basic Operation of ECDIS
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GGA - GPS Quality indicator
Indicator Description Field Acronym
0 Fix not available or invalid -
1 GPS SPS Normal
2 differential GPS Differential
3 GPS Precise Prcs
4 Real Time Kinematic
RTK
5 Real Time Kinematic Float FRTK
6 Estimated dead reckoning DR
7 Manual MAN
8 Simulated -
Indicator values 0 and 8 are degraded values. No acronym
appears in the field but L/L values change to degraded colour
(orange).
A Loran-C device or an older GPS device may not provide position using
the GGA sentence. In this case the GLL sentence may be used. Quality
indicators when using the GLL sentence are shown in the table below.
GLL - system mode indicator
Indicator Description Field Acronym
A Autonomous Normal
D Differential
Differential
E Estimated dead reckoning DR
M Manual MAN
S Simulated
-
N Not valid -
Indicator values S and N are degraded values. No acronym
appears in the field but L/L values change to degraded colour
(orange).
If a GLONASS device is providing position data it is likely to be configured
to send the data using the GNS sentence. Quality indicators when using
GNS are shown in the table below.