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Samples
– samples number per trace:
There are 4 possible values for
Zond-12e Advanced
GPR: 128, 256, 512, 1024.
There is only one possible value for other
Zond-12e
GPR models: 512.
There is only one possible value for other
Python-3
GPR models: 1024.
There are 6 possible values for
zGPR
family: 256, 512, 1024, 2048, 4096, 8192.
Note: If samples rate reduces traces rate is increasing proportionally for
Zond-12e
Advanced
GPR. But traces rate doesn’t depend on samples rate for zGPR family, it
depends on stacking and time range per sample. User has to be very attentive to the
information under the oscillogram window to avoid situation when number of samples is
not enough for correct signal digitizing (at least 5 samples per signal period).
Stacking
– number of the traces that are adding to each other and averaging in a
row, the averaged trace is adding to a profile. The stacking helps to reduce high
frequency noise, but increases the useful signal in a trace, that turns as deeper
penetration. But please note that as higher stacking as lower traces rate. The high
stacking decreases an operator speed to avoid information loss. Stacking is disabled
if defined as 1, but a greater value enables it and is processing on software side for
Zond-12e
and
Python-3
GPR families.
zGPR
family is fundamentally different at
this point. These GPRs are using a powerful FPGA processor and Real Time
Sampling method to digitize the initial received signals, which increase the traces
per second ratio of an order of magnitude. As the result, traces overflow is
converting to stacking (hundreds and thousands of times), but without averaging –
only summation, that enlarge the data sample length from the initial 16 bits to 32
bits.
zGPR
signal-to-noise ratio and its penetration depth are increasing compared
to the previous GPR families.
Scan rate
or trace per second ratio, it is number of received traces per one second:
The maximum value is 240 traces per second for 128 samples per trace and
stacking 1 in
Zond-12e Advanced
GPR.
The maximum value is 56 traces per second for stacking 1 in
Zond-12e Single-
channel
GPR.
The maximum value is 80 traces per second for stacking 1 in
Zond-12e Double-
channel
GPR.
The maximum value is 28 traces per second for stacking 1 in
Python-3
GPR.
The maximum value is 2500 traces per second for stacking 4 in
zGPR
, depends
on the stacking and the selected time range per sample.
Sounding mode
– it has two options:
Continuous
or
Stepped
. The first one, most
commonly used option, assumes that after data acquisition start, the GPR
continuously perform sounding until
Stop
button (or
Esc
key) pressing.
Stepped
profiling is used in cases, when it is impossible to move the antenna continuously
along the route or it is necessary to achieve the greatest sounding depth. This
requires more time from the user for the sounding. Each individual trace adds to the
profile on user key press (
Enter
– trace acquiring,
Spacebar
- trace acquiring and
mark assignment). It is better to use increased stacking for this option. The
Stepped
option profiling technique uses the following way: place the antenna on an
acquisition point (antenna is not moving while data acquisition!), collect a single
(stacked) trace, place the antenna on the next point, collect the next trace, continue
the data acquisition step-by-step equidistantly, along the profiling route and
