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Glossary
A
Auto-Gain
Similar to Time-Gain except the software decides the coefficients to be applied to give a
response across the depth range without over amplifying the trace.
B
Background removal
Background removal is used to remove horizontal and nearly horizontal features in the
radargram by subtracting a calculated mean trace from all traces, sample by sample. It can be
useful for removing the direct airwave (first arrival) or ringing (due to poor ground conditions)
from the data. Care must be taken in this process not to remove real linear features from the
data.
D
Differential GPS (DGPS)
Differential GPS, uses satellites and a correction from a reference station/satellite, accuracy
around ± 0.5-2 m. The available systems for the Easy Locator Controller are currently EGNOS
(Europe), WAAS (USA), GAGAN (India) and MSAS (Japan).
G
GPR profile
Individual line of GPR data represented in a cross-sectional (profile) view of the sub-
surface.
Ground Penetrating Radar
Geophysical method that uses radar pulses to image the subsurface
H
Hyperbola
The type of reflection often associated with a round object or a utility, especially when the
angle (profile) of the radar is at 90 degrees to the utility. It is a distinctive “n” shaped
reflection.
N
Noise
Typical GPR reflection profiles contain noise and unwanted reflections that are produced by
antenna "ringing", differences in the coupling of energy with the ground, multiple reflections
that occur between the antenna and the ground surface and system and background
"noise".
