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the software calculates the time range per trace and outputs it to the Range field,
the estimated penetration depth for the selected medium to the Depth field.
Gain
– it is digital gain (amplification) of the received traces. Due to the fact that
the signal’s strength is rapidly decreasing while it is propagating along the soil, the
gain of the signal should be increased while the depth is increasing too. Therefore
at the end of the trace the gain should be greater than in the beginning. You can set
the gain function as a polyline connecting up to 10 vertexes, where each of them
can be adjusted within 0-84 dB (for
Zond-12e
GPR family and
Python-3
GPR) or
0-168 dB (for
zGPR
family). Gain is used only for the GPR data output. The
number of vertexes could be changed pressing keys from 2 to 9 in the
Digital gain
function setup
window. Press 0 to get 10 vertexes. Vertex navigation is possible by
the arrow keys
and
and
and
to adjust the gain levels. The simplest useful
gain function has 2 vertexes with values 0 dB at the beginning and 48 dB at the end.
If such gain is not optimal it is possible to change it at any time in the post-
processing (take a look on Section 11. Profile handling on page 44).
Note: The acquired GPR data are saved on the hard drive in the original shape (without
gaining). Gaining is just a software tool and is used for data visualization purposes only.
High-pass filter
– cutoff frequency selection of the high-pass filter for received
signals to attenuate low-frequency noises, which arises while antenna is crossing
the rough terrain or due to antenna architecture. The following high-pass filters are
available for different types of the GPR:
o
Zond-12e
GPR family – there are different hardware filters states (
OFF
,
Weak
,
Strong
and
Super Strong
). Please follow the software recommendations.
Customized
filter is a digital software real-time bandpass filter and it disables
hardware high-pass filter. Customized filter frequency band is modified in filter
setup window that outputs the band curve and signal’s spectrum in the real time.
Frequency band is characterized by its vertexes (each vertex corresponds to filter
cutoff frequency). To navigate between filter’s vertexes use < and >, or tab keys.
Changing vertexes’ position (filter cutoff frequency) could be done by
and
keys.
Note: It is recommended to use Customized High-Pass Filter if you are familiar with the
spectrum analysis and the digital signal processing only. Otherwise it is better to use
hardware filters on the base of software recommendations.
o
Python-3
and
zGPR
family – there are two options to acquire data without high-
pass filtering (option
OFF
) or using digital software
Preset
filter. Software
automatically calculates cut-off frequencies for the
Preset
high-pass filter on the
base of chosen antenna.
Real-time filter
(for
Zond-12e
GPR family and
Python-3
GPR) – real-time filter
choise for background noises elimination. The constant background signals could
be seen on the profile as a horizontal lines that do not change intensity and the time
position. Such useless signals may hide the useful signals.
Note: The acquired GPR data are saved on the hard drive in the original shape (not
filtered) in case of
Customized
or
Real-time
filtering. Filtering (the same as a Gain
function) is just a software tool and is used for data visualization purposes only.
