| 摘要 |
Periodic measurements of changes occurring in the period of an oscillator signal (16), indicating the initial presence of a vehicle over an inductive sensor (12), are recorded and used to estimate the time rate of change. A vehicle entry time is then calculated (20) by dividing the magnitude of period change by the time rate of period change, and speed is calculated by dividing the entry distance by the vehicle entry time. Multiple vehicles may also be detected and vehicle length determined. <IMAGE> |
