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QuintSonic 7
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To ensure an optimal echo extraction adapted to your setting of task, different processing methods
and setting options are available. All these method have one thing in common: they clip out the
various portions of unwanted echoes from the echo signal. This procedure is referred to as
“clipping” and is subdivided into two different methods. With the so-called “time-clipping”, the
processing will take place along the time axis (x-axis). The limits used in time-clipping represent
time values. With the amplitude-clipping, the processing takes place by means of different
amplitude values in amplitude direction (y-axis).
After the clipping has been performed, the preprocessor will extract the echoes accordingly. This
will be done by searching for echo pulses on the remaining curve section. The maximum of a
positive pulse determines the position of a positive echo whereas the minimum of a negative pulse
determines the position of a negative echo. The detected echoes will be represented on the echo
signal A-scan image as vertical lines at their respective time positions.
8.3.2
Time-clipping
For processing reasons, the echo signal delivered by the algorithm always covers a time domain
being a little bit larger than indicated by the set measuring range. The time-clipping will clip off all
portions beyond the measuring range. Currently, the time-clipping is defined by the size of
measuring range and cannot be changed.
8.3.3
Amplitude-clipping
By means of the amplitude-clipping, portions of the echo signal curve containing unwanted echoes
can be extracted from the echo extraction. QuintSonic 7 offers three different clipping methods
adapted to different settings of task. According to the clipping method, one or two adjustable limits
are used. It depends on the limits whether echoes will be extracted from a part of a signal curve or
not. According to the clipping method, the limits will cover either the total time domain of signal or
only a part of it. The individual clipping methods and their effects will be described below in detail.
The settings will always be indicated as a percentage of the dynamic range of amplitude. The
dynamic range of amplitude is shown at 100% once the amplitude zoom factor is adjusted to 1
(see also section 7.4.1). To give you a hint for orientation: The amplitude of reference signal is
always 94%; the amplitude of the coupling echo and of the layer signal echo are clearly below this
value for all applications.
The two coupling echoes are mandatory for evaluation. During the verification procedure, the
system will check for each measurement whether the coupling echoes are present and whether
they are correct. If the check will provide a negative result, measurement will be null and void and
the error message “coupling echo failure” will appear. For that reason, when setting the clipping
parameters, make sure not to accidentally suppress the coupling echoes.