| 摘要 |
PROBLEM TO BE SOLVED: To provide "a vehicle-mounted navigation device and a vehicle travel direction detection method" capable of correctly determining the travel direction of one's own vehicle even when a back signal cannot be acquired without requiring special hardware such as an adapter for acquiring the back signal and capable of contributing to an improvement in own vehicle position accuracy. SOLUTION: In the vehicle-mounted navigation device determining the own vehicle position using respective positioning functions utilizing satellite navigation and autonomous navigation together, a vehicle velocity detected on the basis of the positioning functions of the autonomous navigation and a GPS direction detected on the basis of the positioning function of the satellite navigation are monitored, and when the vehicle velocity is at a threshold or more, it is determined that the own vehicle advances (S3, S4). When the vehicle velocity is lower than the threshold and the amount of a variation in the GPS direction is at a threshold or more, it is determined that the own vehicle is switched from advancing to retreating, or vice versa (S6, S7). COPYRIGHT: (C)2008,JPO&INPIT
|
