Ref-Systems Raw Data - NAVIS NavDP 4000 Series Operation Manual

Sensors and Ref-Systems Raw Data
D.2 Ref-Systems Raw Data
Differential GPS
Type
GPS
GGA Message: Global Positioning System Fix Data. Time, Position and Fix Related Data for a
GPS Receiver
The message format:
$--GGA,hhmmss.ss,llll.ll,a,yyyyy.yy,a,x,xx,x.x,x.x,M,x.x,M,x.x,xxxx * hh
where:
hhmmss.ss — Time (UTC)
llll.ll — Latitude
a — N or S (North or South)
yyyyy.yy — Longitude
a — E or W (East or West)
x — GPS Quality Indicator:
0 — Fix not available,
1 — GPS SPS mode,
2 — Differential GPS SPS mode,
3 — GPS PPS mode,
4 — Real Time Kinematic. Satellite system used in RTK mode with fixed integers,
5 — Float RTK. Satellite system used in RTK mode with floating solution,
6 — Estimated (dead reckoning) mode,
7 — Manual input mode,
8 — Simulator mode,
9 — WAAS.
xx — Number of satellites in view, 00–12
x.x — Horizontal Dilution of precision
x.x — Antenna Altitude above/below mean-sea-level (geoid)
M — Units of antenna altitude, meters
x.x — Geoidal separation, the difference between the WGS-84 earth ellipsoid and mean-sea-level (geoid), "–" means
mean-sea-level below ellipsoid
M — Units of geoidal separation, meters
x.x — Age of differential GPS data, time in seconds since last SC104 type 1 or 9 update, null field when DGPS is not
used
xxxx — Differential reference station ID, 0000–1023
hh — Checksum
Example
$GPGGA,110621.86,3000.12870,N,09000.48093,W,2,05,1.2,,,,,10.0,0100 * 5F
Doc. 000.JDP-10000-OME, rev.3.3.13/"2102.$–17A-Advanced"
Data
Lat, Lon, Quality, Number
of satellites, HDOP, COG,
SOG
Comments
The system receives GGA and VTG mes-
sages from GPS. VTG is an option. Lati-
tude, Longitude, Quality, Number of satel-
lites, HDOP are taken from GGA-message.
COG, SOG are taken from VTG-message.
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