Mechanical Operation; Multi-Radar System - Furuno WR2120 Installation Manual

1.3.

Mechanical Operation

This system observes the development of rain clouds outputs the intensity of precipitation, the
speed of rain clouds (Doppler speed) and observes rainfall phenomena. It is capable of high
resolution rain observation, rain cloud, precipitation density and speed observation. The
solid-state transmitter replaces previous aging devices such as a magnetron.
raindrop
Ground clutter
Rain gauge
The area sampled by the radar increases with distance. The wider the beam the greater the
likelihood of sampling a mixture of precipitation types and also a greater the likelihood of
sampled both inside and outside a cloud. Obstacles can also block a portion of the radar beam
resulting in an artificially high power return.
Radar unit
mounting point
Ground projection point
The diagram shows the comparison between ground surface and height of
radar beams
Required accuracy for leveling:
Although 0.2 degrees is an acceptable level, it
may cause a 104.9m difference at a 30km
distance from radar. For best target accuracy
make mount level 0.0 to 0.1 degrees.
1.4.

Multi-radar System

The single X-band weather radar can be difficult to avoid problems with blind areas due to
buildings, mountains or strong signal extinction by heavy rain.
Furuno provide multi-radar system that consists of three radar systems. While two radar systems
are detecting and tracking rain clouds and observing their movements, the other one is working as
RHI sector scan mode at high speed and cutting through the clouds to observe their internal
structures. It is very difficult to complete signal processing of all the radar systems on single PC
because of the CPU performance. Therefore signal processing is distributed among the PC of
each radar system, and all the data are gathered on the central PC and composited into one
synchronized image.
hail
sun
wind
Evaporation
graupel
Ice crystal snowflake
Upper radar beam
Middle radar beam
Lower radar beam
Observation point
Ground surface
Ground projection point
3
Observation area