Data Size - Furuno WR2120 Operator's Manual

7.4. Data Size

- Standard setting of single scan size (one complete azimuth rotation). File size per hour
12,960,088 byte x 3600 sec. / 6 sec. = approx. 7.8GB (7,776,052,800)
- File size at 30 days
7,776,052,800 byte x 30 days x 24 hrs. = approx. 5.6TB
Observation
Header angularity
information
80 + ( (6
Notice:
Basically data capacity can be compressed around 50 to 70%. However the compression ratio depends
on weather condition (Clear weather data will compress into smaller file than active weather data).
If the user would like to decrease the actual data size, some data must be eliminated to reduce generated
file size. Data settings can be adjusted in RainMap to reduce the range of data points and the sweep time
per rotation.
For "csv" format one file will be generated for each checked item and each scan rotation and output to csv
file.
All normal configured data required for csv file format will be saved in each file regardless of the individual
checked fields to ensure structured file information.
1) Sample 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]
2) 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 capture accurate data it is necessary to scan hemisphere over the radar while changing
its elevation angle as shown on Figure 7.1.
The WR2120 radar will output the data files for each elevation angle. When using eight elevation angles,
eight data files will be generated that will require up to 15.55784 MB, however this depends on settings.
Requirement of the data transfer speed is decided by the time span needed to make one set of volume
scan data. This time span will depend on the scanning speed of antenna.
Within this document we present some examples of scanning strategies and generated data size
calculations. The minimum transfer speed requirement will be calculated using these total file sizes and
the time span of one volume scan.
Observation
data
+ 2) + (18 x
Figure 7.1: Basic volume scan
Range
Total
direction
sweep
data
e.g. 1000)) x e.g. 720
9km
・ ・
・
3km
2km
1km
67
Quantity of every
scan
= 12,960,088 byte
・ ・
・