pulseEKKO PRO
3-System Setup Parameters
45
The DVL can be set up to read and log GPS information collected during data acquisition with the GPR
system. GPS information can be logged in two different ways:
1) For every trace collected by the GPR system, or
2) Every time the user adds a fiducial to the data by pressing the Fiducial button or the A button
(Section 5.4: P72).
This feature provides a means of capturing GPS information to an independent file.
Note that the GPS
information is NOT automatically integrated with the GPR data.
After data acquisition is complete, the data
can be downloaded to a PC and the EKKO_View Deluxe software can be used to integrate the GPS data
with the GPR
data.
In order for the DVL to read the GPS data string, the GPS settings for the specific GPS receiver must be
input into this menu. There are 4 important items that must be input correctly for the DVL to display the
GPS strings: Baud Rate, Stop Bits, Data Bits and Parity. These are discussed in more detail below. The
default values listed below are the values that are typically used. Read the GPS Receiver User’s Guide or
experiment with the settings to find the correct ones.
Once these 4 items are set correctly you should be able to run Test GPS with Listing 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.
3.3.4.1
GPS Recording Mode
There are three GPS Recording Modes available:
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.
Reading every x traces
mode means that every time the GPR collects 1, 5, 10, 20 or 50 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 (Section 8.3: P106).
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:
