Sensors & Software pulseEKKO, Product Manual

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System Configuration
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is moved and the receiver is again moved at regular intervals (you could also have the
Receiver fixed and the Transmitter moved). This process is repeated until you have
achieved the desired coverage. Each time the Transmitter is moved, a new data
collection line is started.
•
Transillumination
– VRP – Short for Vertical Radar Profile. In this survey, the
transmitter is fixed and the receiver is moved in steps at right angles to the transmitter
orientation. In the case of borehole radar, the transmitter is on the surface and the
receiver is moved down the borehole. The transmitter is then moved to another position
at a specified interval on the surface and the process is repeated.
Refer to the Borehole GPR manual for more details.
6.2.2 Start Offset
Reflection Surveys
Normally, most lines start at position zero; however you may want to specify a start offset for a
given line (e.g. 2m). This may be necessary if an obstruction prevents you from starting at a
consistent position relative to other lines. When you start collecting data, the position axis
would start at this offset value. Negative values can also be entered. Pressing
Start Offset will
display the screen in Figure 6-15.