| 摘要 |
PROBLEM TO BE SOLVED: To accurately extract distribution of speed of a moving body using a space-time differentiation method by providing a means for time difference calculation, self-estimation quantity calculation, judgment, azimuth controlling and sound source location. SOLUTION: In the device, time difference between time periods that sound signals outputted from a measurement sound source AOB reach a pair of sound collection devices 111, 112 is calculated every specified time interval. A self- estimation quantity 120b which is to be a criterion for judging efficiency of the calculated time difference is calculated. The efficiency of the time difference is judged based on the self-estimation quantity 120b. When it is judged that the efficiency is low, an azimuth is changed and when it is judged that the efficiency is high, the measurement sound source AOB is normalized based on the time difference. That is, azimuth of a pair of the sound collection devices 111, 112 are controlled so that the efficiency of the time difference between time periods that the sound signals outputted from the measurement sound source AOB reach a pair of sound collection devices 111, 112 becomes high, thereby locating the measurement sound source AOB with high accuracy. |
