Furuno WR2120 Operator's Manual page 19

Scans vertically (RHI) while moving horizontally, continuously within a preset azimuth and elevation
range generating a 3 dimensional rectangular solid angle. Horizontal data is not saved.
It continuously moves between the preset clockwise and counter clockwise azimuth and horizontal
limits.
Example of Settings:
The RainMap setting should be entered as
shown in table 3 to observe the parameters
shown below:
Elevation angle: 3.5 to 22.0 deg.
Range of azimuth angle: 30.0 to 60.0 deg.
Azimuth direction: 2.0 deg. (6.0 rpm interval)
Volume scan [3D data] (Refer to Figure 2.7)
This mode activates PPI scan to change the
elevation angle up to 32 steps. It references the
Volume Scan Period and RainMap time
indication.
Volume Scan is an observation of the azimuth
rotation speed and multiple elevation angles as
one complete pattern. Observation starts at the
specified minute (0 second) of every set interval.
Whatever set operation interval is used, all
selected steps must be completed within the
specified interval time. These volume scan
periods include, 1 (60 / [h]) 1 minute, 2 minutes,
3 minutes, ..., 2 (30 / [h]) 2 minutes, 4 minutes, 6
minutes, etc. Therefore, it is necessary to
consider the elevation angle value, observation
rotation speed (rpm), moving speed to elevation
direction (rpm), time to stabilize after elevation
change (fixed at 10 deg.), and observation
interval for setting.
For example setting will fail with following settings. 6.0 rpm azimuth rotation speed for 6 rotations in
one minute would seem to be a correct setting when observing 6 elevation angles with 1 minute
intervals (setting the operation interval to 1 (60 /
[h]). However in Volume Scan, movement occurs
in the elevation direction and does not display
while moving from one elevation to the next
elevation Because of the additional time required
for these elevation movements the above
observation scenario of 6.0 [rpm] AZ rotation
speed cannot be completed within the 1 (60 / [h])
volume scan period.
Example setting:
When observing these 6 elevation angles (3.5 /
5.5 / 9.0 / 12.0 / 16.2 / 22.0 [deg]) every one
minute, they can observed within a 58 second
period by using settings in Table 2.4.
(Rotation set to 7.0 [rpm] in azimuth direction)
Note 1: The ending time of scenario will be
different if elevation angle [deg] is
different even when using the same (0
to 5) elevation numbers.
Note 2: Elevation movement azimuth rotation
speed [deg] is fixed at 6.0 deg.
S2E-17-0208_OM_WR2120_C
Key
EL rotation speed [rpm]
AZ start angle [deg]
AZ end angle [deg]
AZ step angle [deg]
EL start angle [deg]
EL end angle [deg]
Volume scan period [min]
Sync. Scan mode
EL transition speed [rpm ]
AZ rotation speed [rpm]
EL angel 0
EL angel 1
EL angel 2
EL angel 3
EL angel 4
EL angel 5
AZ rotation speed [rpm]
AZ start angle [deg]
AZ end angle [deg]
EL angle 0 [deg]
EL angle 1 [deg]
EL angle 2 [deg]
EL angle 3 [deg]
EL angle 4 [deg]
EL angle 5 [deg]
10
Table 2.3
Value
6.0
30.0
60.0
2.0
3.5
22.0
Key Value
1 ( 60 / [h] )
AUTO
4.0
7.0
3.5
Table 2.4
5.5
9.0
12.0
16.2
22.0
Key Value
7.0
30.0
60.0
3.5
5.5
9.0
12.0
16.2
22.0
Table 2.5