Samyung Navis 3800, Руководство пользователя

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GPS Overview
The Global Positioning System is based on a radio navigational system using
satellites. An unlimited number of users are provided with accurate three-dimensional
positions. This 24/7, worldwide coverage, is available under any weather condition.
GPS can provide two-dimensional and three-dimensional position information. 3D
positioning is mostly used in aircraft or other applications requiring latitude, longitude
and altitude. The 3D mode requires a lock on 4 satellites to accurately acquire the
position.
Surface vessels use 2D positioning, as only latitude and longitude is needed. In 2D
mode, positioning requires a lock on only 3 satellites to accurately acquire the
position.
Once the GPS Plotter has received an accurate fix from the satellites, ship’s position,
bearing, time, speed and other operations can be calculated.
GPS(Global Positioning System) has two types, 3 Dimensional and 2 Dimensional.
3D positional data has been sued in aviation, which requires Latitude, Longitude and
Height.
To provide 3D positional data, the system requires 4 satellites.
2D positional data has been used in vessel/ship navigation, which requires only
Latitude and Longitude.
To provide 2D positional data, the system requires 3 satellites.
GPS provides an accurate positional data by receiving satellite signals.
GPS chartplotters provide ship position, bearing, time, speed and many more.
Furthermore, plotters provide information for navigation and other data on the map
such as latitude/longitude, tracks, waypoints, event marks and more on high-
resolution LCD.