Raymarine LIGHTHOUSE 3, Advanced Operation Instructions

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12.11 Doppler Radar overview
Doppler Radar technology makes it easier to track moving targets with significant ground speed
exceeding 3 knots.
Typically Doppler Radar works best with objects that are moving directly towards or away from the
vessel. Doppler Radar can highlight only those targets that are moving relative to the vessel (e.g.
other boats, but not land or buoys, for example).
Doppler Radar works by transmitting a microwave signal which is then reflected off a desired moving
target at a distance. By analyzing how the object's motion has altered the frequency of the returned
signal, the Doppler Radar can interpret the variation to provide highly accurate measurements of a
target's direction of travel, relative to the Radar scanner.
Doppler Radar technology is particularly beneficial in a marine environment, where poor weather
conditions and visibility can make target tracking difficult. Additionally, it is not always easy to
interpret the information displayed by traditional Radar technology. With the integration of Doppler
information, the process of matching on-screen radar returns with real-world objects becomes
a much simpler task.
Doppler mode
When a compatible Radar is connected Doppler mode is available.
Doppler mode — Enabling and disabling
Doppler mode is enabled from the Main menu: Menu > Doppler .
With Doppler mode enabled the color palette will change to the default Doppler palette, all
approaching targets will be colored Red and all targets moving away from you will be colored Green.
Doppler mode is suspended at ranges of 12 nm and greater. The Radar color palette will remain
the same but targets will not be highlighted.
Doppler mode — Color palettes
Doppler has unique color palettes which help to ensure the Red and Green Doppler targets stand
out from the Radar image. When Doppler is enabled the standard color palette setting will show only
the unique Doppler color palettes:
Doppler grey , Doppler blue and Doppler yellow .
The Color palettes can be selected from the Presentation tab: Menu > Settings > Presentation .
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