SeaBat Sonar UI - User Manual
Operation
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The sensor data can only be recorded when these sensors are interfaced
with the sonar system. This can be done in the IO Module. An alternative
is that the position, attitude and heading are send by PDS2000 to the IO
Module. Then only the external clock with 1PPS and the sound velocity
has to be interface in the IO Module.
4.8.1.3 Compressed Water Column
It is possible to reduce the amount of recorded Water Column Data.by
enabling the filter(s):
Remove phase Data
Compress to 8 bits
Remove beyond detection point
Furthermore it is possible to reduce the record data size by selecting a
downsampling type and a corresponding downsampling factor.
Downsampling” means that only 1 of N mag/phase samples are kept.
Where ‘N’ is the “downsampling factor” value. The “downsampling type”
controls how that 1 value is determined.
It is possible to select three types of downsampling:
1
Middle of window:
The 1 sample value kept is the middle one in each “window” (e.g.
if N = 5, then sample 3, 8, 13,
18, …are kept).
2
Peak:
The 1 sample value kept is the largest of each “window” of N
samples.
3
Average:
The 1 sample value kept is the average of all N samples in each
“window”.
For example, if the “Remove phase data” option and the Downsampling
option (with factor 5) are selected, then the resulting compressed
watercolumn record will be 1/2 * 1/5 = 1/10 the size of corresponding
7018 mag+phase watercolumn record.
Figure 4-54
Compressed Water Column
4.8.1.4 Status
Figure 4-55
Status raw data recording
The Status box lists the status of the Raw Data Recording with the current
file name, size of the recording file, records logged, the number of records
that are added to the recording file, and the percentage of free disk
space.
