User's Manual

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JMA-9100 Instruction Manual > 6.TRUE AND FALSE ECHOES ON DISPLAY > 6.3 SEA CLUTTER AND RAIN AND SNOW
CLUTTER
c. Coping with sea clutter and rain and snow clutter
When the weather is bad and the ocean is rough, the use of an S band radar is
effective because the radar is not influenced by sea clutter so much and
attenuation due to rain drops is small. When an X band radar is used, reducing the
pulse width will reduce the influence by spurious waves, and also the spurious
wave rejection function effectively works; therefore, the use of short pulse is
effective when the weather is bad. By using image processing functions PROCl 1
to 3, it is expected that spurious waves are further suppressed. Since optimal
settings for those items can be automatically made by using the function mode, it
is recommended that STORM or RAIN be used by selecting the function mode
when the weather is bad. For details of the function mode, see Section 3.9 "USE
FUNCTION KEY [USER]".
However, these functions may make some targets invisible, particularly targets
with higher speeds.