| 摘要 |
PROBLEM TO BE SOLVED: To provide a navigation apparatus of a mobile unit for achieving smooth communication with circles even if entering an area outside a communication range. SOLUTION: The navigation apparatus registers position information on the mobile unit to a center and acquires position information on other mobile units from the center for displaying on a drawing map. The navigation apparatus informs the center of the current position of the mobile unit as an entry position to an area outside the communication range, where the mobile unit enters the area outside the communication range from the area inside the communication range, informs the center of an estimated escape position and an estimated escape time in the area outside the range, and informs the center of the current position of the mobile unit when escaping from the outside-of-circle is performed for moving to the area outside the communication range and moving to the area inside the communication range. Additionally, another navigation apparatus acquires the position information of the mobile unit in groups from the center to display the acquired position of the mobile unit on the drawing map. COPYRIGHT: (C)2005,JPO&NCIPI |
