Gps Status - Lighthouse a65 Installation And Operation Instructions Manual

6.14 GPS Status

The GPS status page enables you to view the status
of the available satellites that are compatible with
your receiver.
The satellite constellations are used to position your
vessel in the Chart and Weather applications. You
can set up your receiver and check its status from
the GPS Set-up menu: Homescreen > Set-up >
System Settings > GPS Set-up. For each satellite,
the screen provides the following information:
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1. Sky view
2. Satellite status
3. Position and fix information
Sky view
Sky view is a visual representation that shows
the position of navigation satellites and their type.
Satellite types are:
• Circle — A circle identifies a satellite from the
GPS constellation.
• * Diamond — A diamond identifies a satellite from
the GLONASS constellation.
• Square — A square identifies an (SBAS)
differential satellite.
Note: GLONASS satellites are only available
when connected to a compatible receiver such as
the built-in receiver of an a9x or a12x MFD.
Satellite status area
The Satellite status area displays the following
information about each satellite:
• Type — Identifies which constellation the satellite
belongs to.
• ID — Displays the satellites identification number.
• CNO (Carrier-to-noise ratio) — Displays the signal
strength of each satellite shown in the Sky view:
– Grey = searching for satellite
– Green = satellite in use
– Orange = tracking satellite
• Azimuth and Elevation — Provides the angle of
elevation and azimuth between the location of the
receiver and the satellite.
Position and fix information
The following positional and fix information is
provided:
• Horizontal Dilution of Precision (HDOP)
— HDOP is a measure of satellite navigation
accuracy, calculated from a number of factors
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including satellite geometry, system errors in
the data transmission and system errors in the
receiver. A higher figure signifies a greater
positional error. A typical receiver has an accuracy
of between 5 and 15 m. As an example, assuming
a receiver error of 5 m, an HDOP of 2 would
represent an error of approximately 15 m. Please
remember that even a very low HDOP figure is
NO guarantee that your receiver is providing an
accurate position. If in doubt, check the displayed
vessel position in the Chart application against
your actual proximity to a known charted object.
• Estimated Horizontal Position Error (EHPE)
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— EHPE is a measure of the estimated error of
a position fix in the horizontal plane. The value
displayed indicates that your position is within a
circle radius of the stated size 50% of the time.
• Fix status — indicates the actual mode the
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receiver is reporting:
– Fix — Satellite fix has been acquired.
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– No Fix — No satellite fix can be acquired.
– D Fix — A differential beacon fix has been
acquired.
– SD Fix — A differential satellite fix has been
acquired.
• Position — Displays the latitude and longitude
position of your receiver.
• Date / Time — Displays the current date and time
generated by the position fix in UTC format .
• Mode — Identifies wether the receiver is working
in differential mode or non-differential mode.
• Datum — The receiver's datum setting affects
the accuracy of the vessel position information
displayed in the Chart application. In order for your
receiver and MFD to correlate accurately with your
paper charts, they must be using the same datum.
Global Navigation Satellite Systems (GNSS)
A GNSS is a system of satellites that provides
autonomous geo-spatial positioning that allows
electronic devices with compatible receivers to
determine their location (longitude, latitude and
altitude).
Operational GNSS
• GPS (NAVSTAR) Global Positioning System
US owned constellation of satellites that became
fully operational in 1995.
• GLONASS acronym for "GLObalnaya
NAavigatsionnaya Sputnikovaya Sistema" or
"Global Navigation Satellite Systems"
Russian owned constellation of satellites that
offered global coverage in 2010.
Planned GNSS
• Galileo
European satellite constellation in initial
deployment phase due to become operational in
2020.
• COMPASS / Beidou-2
a Series / c Series / e Series