Smart Systems User’s Manual Version 1.1
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Once these 4 items are set correctly you should be able to run System Test #1 and have
GPS information written to the screen.
When the logging of GPS information is enabled, during data acquisition a message will
appear in the bottom left-hand corner of the DVL screen indicating whether GPS data is
successfully being received (see Section 6.2.4).
Mode
There are three GPS modes available:
1)
Off
mode means that a GPS receiver is not connected to the DVL so no GPS
information is being logged. This should be the setting if you do not have a GPS
receiver.
2)
Reading every x traces
mode means that every time the Noggin
plus
collects a
user-defined number of traces of GPR data, a data string of GPS information will
be added to a file. This file has the same name as the data file i.e. LINE6, but with
a GPS extension. This file can be accessed after transferring the GPR data files to
an external PC (see Section 6.4.1).
For example, if the number of traces is set to 1, the LINE6.GPS may look like this:
Trace #1
$GPGGA,134713.00,4338.221086,N,07938.421365,W,2,06,2.1,152.51,M,-35.09,M,5.0,0118*79
$GPVTG,34.0,T,,,001.4,N,002.5,K,D*70
$GPGSA,A,3,30,26,10,13,24,06,,,,,,,4.2,2.1,3.6*36
Trace #2
$GPGGA,134713.00,4338.221086,N,07938.421365,W,2,06,2.1,152.51,M,-35.09,M,5.0,0118*79
$GPVTG,34.0,T,,,001.4,N,002.5,K,D*70
$GPGSA,A,3,30,26,10,13,24,06,,,,,,,4.2,2.1,3.6*36
Trace #3
$GPGGA,134713.00,4338.221086,N,07938.421365,W,2,06,2.1,152.51,M,-35.09,M,5.0,0118*79
$GPVTG,34.0,T,,,001.4,N,002.5,K,D*70
$GPGSA,A,3,30,26,10,13,24,06,,,,,,,4.2,2.1,3.6*36
Trace #4
$GPGGA,134713.00,4338.221086,N,07938.421365,W,2,06,2.1,152.51,M,-35.09,M,5.0,0118*79
$GPVTG,34.0,T,,,001.4,N,002.5,K,D*70
$GPGSA,A,3,30,26,10,13,24,06,,,,,,,4.2,2.1,3.6*36
Note that when the Reading per Trace option is on, it is still possible to add fiducial
markers to the GPS file. These will appear as F1, F2 etc. between the trace
numbers. For example, a portion of LINE6.GPS may look like this:
Trace #85
$GPGGA,134850.00,4338.204868,N,07938.429003,W,2,06,2.1,152.60,M,-35.09,M,4.2,0118*74
$GPVTG,152.6,T,,,002.3,N,004.3,K,D*43
$GPGSA,A,3,30,26,10,13,24,06,,,,,,,4.2,2.1,3.7*37
F1
$GPGGA,134850.00,4338.204868,N,07938.429003,W,2,06,2.1,152.60,M,-35.09,M,4.2,0118*74
$GPVTG,152.6,T,,,002.3,N,004.3,K,D*43
$GPGSA,A,3,30,26,10,13,24,06,,,,,,,4.2,2.1,3.7*37
Trace #86
$GPGGA,134851.00,4338.204362,N,07938.428362,W,2,06,2.1,152.40,M,-35.09,M,5.2,0118*72
$GPVTG,136.9,T,,,002.8,N,005.2,K,D*45
$GPGSA,A,3,30,26,10,13,24,06,,,,,,,4.2,2.1,3.7*37
3)
Fuducial Tagging
mode means that whenever a fiducial marker (F1, F2 etc.) is
added to the data (see Section 6.2.4), a data string of GPS information will be added
to a file. This file has the same name as the data file i.e. LINE6, but with a GPS
extension. This file can be accessed after transferring the GPR data files to an
