User's Manual

3-System Setup Parameters pulseEKKO PRO
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3.2.5 Antenna Step Size
This specifies the distance the antenna pair will be moved each time to collect a new trace during a
Reflection mode survey (Section 3.4.5: P51).
To properly resolve subsurface targets spatially, it is important that a proper Antenna Step Size be
selected. Too coarse a Step Size may result in missed subsurface targets while too fine a Step Size will
result in large data volumes and slow survey productivity.
This parameter is set under System Setup - GPR Parameters - Antenna Step Size.
The Antenna Step Size value will be set to a default value based on the antenna frequency selected
(Section 3.2.1: P34) as shown in the table below.
Note that the default values can be overridden by changing the Step Size value directly.
When using an odometer to collect data, make sure that odometer has been properly calibrated (Section
3.3.5.1: P48), otherwise positional information will be incorrect.
In CMP mode (Section 6.11: P91), the step size is interpreted to be the total increment in separation
between each trace. Therefore, if each antenna is moved 0.25 metres then the Step Size is 0.5 metres.
Frequency
(MHz)
Recommended
Antenna Step Size
(metres)
Recommended
Antenna Step Size
(feet)
12.5 2 6
25 1 3
50 0.5 1.5
100 0.25 1
200 0.1 0.33 (4 in)
250 0.05 0.166 (2 in)
500 0.025 0.0833 (1 in)
1000 0.01 0.042 (0.5 in)