Juniper Systems Allegro 2 User Guide - Manual (Page 65)

Ch 6 GPS/GNSS 61
NMEA Sentences
Descriptions of the NMEA Sentences shown on the GNSS
control panel menu follow.
„
RMC - Recommended Minimum Specific GNSS Data.
Example of data output: $GPRMC,045824.00,A,4127.31350
,N,11202.79015,W,00.03,022.9,160914,,,A*4C.
The RMC message contains the time, date, position,
course and speed data provided by the GNSS navigation
receiver.
„
VTG - Course over Ground & Ground Speed. The VTG
message provides actual course (CoG) and speed (SoG)
relative to the ground.
„
GGA – Global Positioning System Fix Data. The GGA
message outputs time, position and fix related data. The
fix is based on all available GNSS. This message is similar
to the GNS – GNSS Fix Data GNS message.
„
GSA – GNSS DOP and Active Satellites. The GSA message
contains the GNSS receiver’s operating mode, satellites
used for calculation of the PVT data transmitted by the
GGA message and DOP values. The GPS satellites are
identified by their PRN, which range from 1 to 32. The
WAAS system has numbers 33 to 64 to identify its satellites.
The numbers 65 to 95 are used for GLONASS satellites (64
+ satellite slot number).
„
GSV – GNSS Satellites In View. The GSV message identifies
the number of satellites (SV) in view, satellites’ PRN
numbers, elevation, azimuth and SNR value. One GSV
message may contain data for one to four satellites.
If more than 4 satellites are in view then additional
GSV messages will be generated. Total number of
messages being transmitted and the number of the
current message are indicated in the first two fields of
the message. If multiple GPS, GLONASS, etc. satellites
are in view, then separate GSV messages with Talker ID
GP for GPS satellites in view, GL for GLONASS and GA for
GALILEO satellites will be generated.
„
GLL – Geographic Position – Latitude/Longitude. The
GLL message contains the latitude and longitude of the
present position, the time of the position fix and the status.