User's Manual

12-Survey & Map Mode Noggin

104

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 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 12.4.1: p.108).

For example, if the number of traces is set to 1, the LINE6.GPS may look like this:

Trace #1 at position 0.00

$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 at position 0.05

$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 at position 0.10

$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 at position 0.15

$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 at position 4.20

$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

$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 at position 4.25

$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