Furuno WR-2100, Руководство оператора

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SSE-14-0022_17
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Notice:
Basically data capacity can compress around 50 to 70%. However the compression ratio will be changed by
weather condition (Fine weather data will get smaller after compressed).
If the user would like to reduce the data size on actual condition, it has to decimate the data and reduce the
generated file size. It can decimate the data from the RainMap setting where to reduce the range of data point
and the time of sweeps per rotation.
csv file will generate each checked item of each scan for output csv.
All factors regardless of the checking will save each scan under the circumstances of csv output.
Sample 1: Maximum setting
Azimuth scan speed: 16 rpm
Vertical scan speed: 36 deg/sec.
Elevation angles: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 40 and 50 degrees (14 angles)
Volume scan interval: 1 min.
Required speed = 14 x 15.55784 x 8 / 60 = 29.04 [Mbps]
Sample 2: Reduced setting
Azimuth scan speed: 3 rpm
Vertical scan speed: 6 deg./sec.
Elevation angles: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30 and 40 degrees (13 angles)
Volume scan interval: 5 min.
Required speed = 13 x 15.55784 x 8 / (5 x 60) = 5.39 [Mbps]
Additional explanation:
The weather radar has narrow beam called “pencil beam”. Both horizontal and vertical planes on beam width of
pencil beam are the same.
In order to take accurate data, it is necessary to scan hemi-sphere over the radar for changing its elevation
angle as shown in the Figure 1.
Figure 1. Basic volume scan
The radar, WR-2100 will output the data files for each elevation angle. When use eight elevation angles, eight
data files will be generated that will go up to 15.55784 MB, however it depends on settings.
Requirement of the data transfer speed will be decided by time span that will need to make one set of volume
scan data. Therefore this time span will depend on the scanning speed of antenna.
Hereinafter, this document will be presented from some examples of the scanning strategy and generating
data size by calculation. The minimum transfer speed requirement will be calculated using these total file size
and the time span per one volume scan.
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9km