| 摘要 |
PURPOSE:To simply and quickly search for a present location by detecting own present location and by displaying the page number of a map book which contain the map near the present location. CONSTITUTION:Each of the accurate time signal navigational radio wave transmitted from the global positioning system(GPS) satellites 4, 4...n is received by a GPS receiver 6. A signal processing means 7 obtains each of the arrival time of the navigational radio wave time signals, computes the distance between each of the GPS satellites 4 and own vehicle's location and fixes own present location. Then, a CPU 3 reads all page numbers of a map book 10 from a map information storage section 8, successively reads the reference point of each page and extracts the page number of the map book 10 in which the present location map is contained. Furthermore, the CPU 3 displays the page number and the latitude and the longitude of the present location on a display screen and also displays a mark, which indicates the present location, at the corresponding location on the display screen of the display device 9. |
