Northrop Grumman Sperry Marine VisionMaster FT, User Manual

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Radar/Chart Radar User Guide Glossary
65900010 Glossary-9
NIMA: National Imagery and Mapping Agency. An agency of the United
States government, supplying navigational charts to the United
States Navy.
NM: Nautical mile – The nautical mile is closely related to the
geographical mile which is defined as the length of one minute of
arc on the earth's equator. By international agreement, the nautical
mile is now defined as 1852 meters (1.15 standard miles).
NMEA: National Marine Electronics Association. An association of
manufacturers that has published widely used standards for
navigation and other marine sensor communication. Their
published standards include NMEA 0183, Standard for Interfacing
Marine Electronic Navigational Devices, Version 1.5, December
1987, and Version 2.0, January 1992. This standard is commonly
referred to as simply "NMEA 0183." The ECDIS is designed to use
messages from any navigation, weather, or machinery sensor that
conforms to this standard.
NOAA: National Oceanic and Atmospheric Administration. Agency of the
US government, supplying navigational charts. NOAA charts are
available in S-57 format.
North-up (N UP): Stabilised display – the bearing scale shows 000° at the
top of the chart display (assumed to be True North). The ship’s
heading marker is shown at the appropriate bearing.
P
PAD: Predicted Area of Danger
Parallel Index Lines (PI): A set of parallel lines placed on the video circle
to aid navigation.
Parity: An error-checking procedure in which the number of 1s must
always be the same – either even or odd – for each group of bits
transmitted without error.
Past Position Dots: Equally time-spaced past position marks of a tracked
or reported target and own ship. The co-ordinates used to display
past positions may be either relative or true.
PCB: Printed Circuit Board
PCIO: PC Input/Output