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GeoScope
TM
User’s Manual
© 2013 3d-Radar AS
Page 6
Revision 2.0
Date: 02/07/2013
transverse direction by firing the antenna pairs in a linear sequence from
Antenna Pair #1 to the highest antenna pair.
With the Multi-offset feature, the system offers a higher degree of freedom to
build more advanced scan patterns. It is for example possible to transmit at
Antenna #1 and receive at Antenna # 8, (i.e. with an offset distance along
the cross-line direction). The automatic Common-Mid-Point (CMP) gather
collects traces centered at the antenna in the center of the array with
increasing offsets (normal move-out) as shown in Figure 7. This feature is
used to estimate the wave velocity using standard methods (semblance
analysis) used in seismic processing. Other scan sequences can be
programmed as well. Note that this mode of operation works in a sequential
manner, hence using all possible combinations of transmitter and receiver
antennas will slow down the data collection speed somewhat.
Figure 7 – Common-Mid-Point Gather.
1.4
Accessories/options
The GeoScope
TM
can be used in combination with digital video camera, GPS
and CamLink
TM
software from RoadScanners for simultaneous recording of
video, GPR data and GPS data.
The antenna array can be equipped with a 2-wheel lightweight trailer
assembly (Figure 8). The trailer connects to a standard ISO 50mm ball hitch
used on cars. For railway operation 3d-Radar can provide railway wheels with
adjustable track width. For high-speed surveys we recommend to mount the
array directly to the vehicle
Figure 8 - Typical GPR setup with a 2-wheel trailer.