File Format ID: nav15

Format Description Creation Date: 2011-08-16

File Type: ASCII, comma-separated values

Record Format: Data records contain "DATA" identifier, external clock ISO-8601 date 
and time, and National Marine Electronics Association (NMEA) 0183 string.

Data Format Description:
The file is generated by Oregon State University's data aquisition system.  Each
file contains metadata about the vessel, cruise, data source, and data itself.  The data
records contain GGA, GSA, GSV, and VTG strings, alternating line-by-line.

Example Record: DATA, 2011-04-11T01:59:57.047Z, "$GPGGA,015957,4437.5473,N,12402.7121,W,2,10,0.8,9.7,M,-21.8,M,,*7C"

where:
     DATA                       Identifies record as data
     2011-04-11T01:59:57.047Z   External datetime stamp (source unknown),
                                  2011   4-digit year
                                  04     2-digit month
                                  11     2-digit day
                                  "T"    date/time separator
                                  01     2-digit hour, 24-hr clock
                                  59     2-digit minute
                                  57.047 decimal seconds
                                  "Z"    UTC
     "$GPGGA etc."                NMEA record (in quotes)

Definitions follow.

Definition of GGA:
GGA - essential fix data which provide 3D location and quality data.

Example Record: $GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47

where:
     GGA          Global Positioning System Fix Data
     123519       Fix taken at 12:35:19 UTC
     4807.038,N   Latitude 48 degrees 07.038 minutes North
     01131.000,E  Longitude 11 degrees 31.000 minutes East
     1            Fix quality: 0 = fix not available or invalid
                               1 = GPS Standard Positioning Service (SPS) mode, fix vali
d
                               2 = differential GPS (DGPS), SPS mode, fix valid
                               3 = GPS Precise Point Positioning (PPS) mode, fix valid
                               4 = Real Time Kinematic (RTK). Satellite system used in
                                    RTK mode with fixed integers.
                               5 = Float RTK.  Satellite system used in RTK mode with
                                    floating integers.
                               6 = Estimated (dead reckoning) mode
			7 = Manual input mode
                               8 = Simulator mode
     08           Number of satellites being tracked
     0.9          Horizontal dilution of precision (HDOP)
     545.4,M      Altitude above mean sea level [meters]
     46.9,M       Height of geoid (mean sea level) above WGS84
                      ellipsoid [meters]
     (empty field) Time in seconds since last DGPS update
     (empty field) DGPS station ID number
     *47          Checksum, always begins with *

If the height of geoid is missing then the altitude should be suspect. Some
non-standard implementations report altitude with respect to the ellipsoid
rather than geoid altitude. Some units do not report negative altitudes at
all. This is the only sentence that reports altitude.

Definition of GSA:
GSA - DOP and Active Satellites

Example Record: $GPGSA,A,3,,5,29,27,12,,30,9,2,21,,,3.6,1.2,3.3*07

where:
     A              Mode: M = Manual, forced to operate in 2D or 3D
                          A = Automatic, 3D/2D
     3              Mode: 1 = Fix not available
                          2 = 2D fix
                          3 = 3D fix
     (fields 3-14)  Space vehicle (SV) IDs of GPS satellites used in position fix
                      (null for unused fields)
     3.6            Positional Dilution of Precision (PDOP)
     1.2            Horizontal Dilution of Precision (HDOP)
     3.3            Vertical Dilution of Precision (VDOP)
     *07            Checksum, always begins with *

Definition of GSV:
GSV - Satellites in view

Example Record: $GPGSV,2,1,08,01,40,083,46,02,17,308,41,12,07,344,39,14,22,228,45*75

where:
     GSV          Satellites in view
     2            Number of sentences for full data
     1            sentence 1 of 2
     08           Number of satellites in view
     01           Satellite Psuedo-Random Number (PRN) ID
     40           Elevation [degrees]
     083          Azimuth [degrees]
     46           Signal strength - higher is better
     (repeat for up to 4 satellites per sentence)
     There my be up to three GSV sentences in a data packet
     *75          Checksum, begins with *

Definition of VTG:
VTG - Velocity made good. The gps receiver may use the LC prefix instead of GP
if it is emulating Loran output.

Example Record: $GPVTG,054.7,T,034.4,M,005.5,N,010.2,K*48

where:
     VTG        Track made good and ground speed
     054.7,T    True track made good [degrees, clockwise from North]
     034.4,M    Magnetic track made good
     005.5,N    Ground speed [knots]
     010.2,K    Ground speed [kilometers per hour]
     *48        Checksum, begins with *

Example Content:
META_VESSEL, "Name",       "Call_Sign", "IMO_Number"
VESSEL,      "R/V Wecoma", "WSD7079",   "076044390"

META_CRUISE, "Cruise_ID",        "Primary_Investigator", "Chief_Scientist", "Marine Technician", "Cruise_Start"
CRUISE,      "dockside",      "dock",             "dock",        "Daryl Swensen",     "2011-03-21T17:00Z"

META_SOURCE, Name, Make, Model, Version, Serial_Number, Location, Destination, Calibration_Date, Calibration_Name.1, Calibration_Value.1, Calibration_Name.2, Calibration_Value.2, Calibration_Name.3, Calibration_Value.3, Calibration_Name.4, Calibration_Value.4, Calibration_Name.5, Calibration_Value.5, Calibration_Name.6, Calibration_Value.6
SOURCE, "xmltocsv", "Oregon State University", "Serial", "2.1 09 Mar 2011", , naruto, gnss_starboardsuite_gps.csv, , configuration file, /usr/local/etc/suds/xmltocsv/generic.yaml, configuration date, 2011-03-09, , , , , , , , 
SOURCE, DataStorm_gnss_starboardsuite_gps, Oregon State University, Serial, S1.0.7, 02-04-A3-42-02-06, gnss_starboardsuite_gps, xmltocsv_v2.1, , IP_Address, 10.240.158.111, , , , , , , , , , 
SOURCE, gnss_starboardsuite_gps, Garmin, GPS 17-HVS, , MARTECH_GPS_001, "0,0,0", DataStorm_gnss_starboardsuite_gps, None, , , , , , , , , , , , 

META_DATA_NAME, Timestamp, Signal
META_DATA_SAMOS_NAME, , 
META_DATA_FORMAT, YYYY-MM-DDThh:mm:ssZ, alphanumeric
META_DATA_UNITS, year-month-dayThour:minute:decimal_secondZ, ASCII
META_DATA_REFERENCE_FRAME, UTC, 
META_DATA_REFERENCE_STANDARD, NTP, 
META_DATA_SOURCE, DataStorm_gnss_starboardsuite_gps, gnss_starboardsuite_gps
META_DATA_PRECISION, 0000-00-01T00:00:00.001, 
DATA, 2011-04-11T00:00:00.158Z, "$GPGGA,000000,4437.5473,N,12402.7120,W,2,11,0.8,8.5,M,-21.8,M,,*70"
DATA, 2011-04-11T00:00:00.286Z, "$GPGSA,A,3,,23,07,04,13,16,03,20,08,10,30,02,1.3,0.8,1.1*36"
DATA, 2011-04-11T00:00:00.432Z, "$GPGSV,3,1,12,48,37,192,43,23,59,104,50,07,47,260,50,04,07,262,43*77"
DATA, 2011-04-11T00:00:00.577Z, "$GPGSV,3,2,12,13,77,345,50,16,39,055,48,03,17,105,44,20,21,176,43*78"
DATA, 2011-04-11T00:00:00.723Z, "$GPGSV,3,3,12,08,19,249,45,10,39,300,44,30,20,043,43,02,07,299,40*7E"
DATA, 2011-04-11T00:00:00.819Z, "$GPVTG,000.0,T,342.6,M,000.0,N,0000.1,K*7C"
DATA, 2011-04-11T00:00:01.129Z, "$GPGGA,000001,4437.5473,N,12402.7120,W,2,11,0.8,8.5,M,-21.8,M,,*71"
DATA, 2011-04-11T00:00:01.257Z, "$GPGSA,A,3,,23,07,04,13,16,03,20,08,10,30,02,1.3,0.8,1.1*36"

References:
