| 摘要 |
PROBLEM TO BE SOLVED: To provide a navigation apparatus which prevents a recognition failure owing to an excess of an input level by changing an input gain according to the running of a vehicle, and enhances its sound recognition performance by performing guidance concerning announcing volume to a user and increasing an S/N ratio. SOLUTION: By this navigation apparatus, a sound input gain is changed according to the running of the vehicle, and in addition an announcement is made to the user concerning the announcing volume according to the change of the sound input gain. Accordingly, the recognition failure by the excess of the input level is prevented, and the sound recognition performance is enhanced by performing guidance concerning the announcing volume to the user and by increasing the S/N ratio in addition. COPYRIGHT: (C)2004,JPO |
