| 摘要 |
A navigation aid for use with printed maps, the aid comprising: (a) a receiver of transmitted signals from a geographic position fixing system such as, for example, GPS, which receiver is operative to determine from the transmitted signals the current geographic coordinates of the navigation aid; (b) an electronic database means storing a plurality of sets of data, each set of data comprising definitive parameters of a respective map or series of maps for definition of the correspondence between the coordinates of the map grid associated with the map and the coordinates of the geographic position fixing system; (c) a map identity input means for the user to enter into the aid the identity of the map to be used therewith and data selection means responsive to the input identity to select from the database the set of data corresponding to the map identified by the user; (d) processing means for converting the currently determined geographic coordinates into the corresponding map grid coordinates of the identified map using the selected data; and (e) a display for displaying the thus-established corresponding map grip coordinates to the user. |
