GGA - Global Positioning System Fix Data, Time, Position and fix related data fora GPS receiver.

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 Field Number: 
  1) Universal Time Coordinated (UTC)
  2) Latitude
  3) N or S (North or South)
  4) Longitude
  5) E or W (East or West)
  6) GPS Quality Indicator,
     0 - fix not available,
     1 - GPS fix,
     2 - Differential GPS fix
  7) Number of satellites in view, 00 - 12
  8) Horizontal Dilution of precision
  9) Antenna Altitude above/below mean-sea-level (geoid) 
  10) Units of antenna altitude, meters
  11) Geoidal separation, the difference between the WGS-84 earth
     ellipsoid and mean-sea-level (geoid), "-" means mean-sea-level
     below ellipsoid
  12) Units of geoidal separation, meters
  13) Age of differential GPS data, time in seconds since last SC104
     type 1 or 9 update, null field when DGPS is not used
  14) Differential reference station ID, 0000-1023
  15) Checksum