| 摘要 |
When a mobile terminal transmits information to an information service centre, the terminal stores positional data of plural points detected by a positional data detector such as a GPS satellite into a memory. The mobile terminal transmits an instant status data, positional data and the terminal ID when an emergency such as an accident, sudden illness occurs. At this time, an appropriate data compression is conducted responsive to a travelling status, such as using relative information, a data-(non-) existing-flag, and a number of points, so that the data volume to be transmitted can be reduced. As a result, the accuracy of positional data is maintained and yet the data transmission time is shortened. |
