| 摘要 |
<p>PROBLEM TO BE SOLVED: To correctly detect the entrance and exit by receiving a radio wave signal from a transmitter by means of a first or a second receiver and executing a prescribed judgment only unless another receiver receivers the radio wave signal from the transmitter within a prescribed time. SOLUTION: When an electric field strength comparing circuit judges that reception is alternately executed by the receivers 30a and 30b owing to the fluctuation of reception electric field strength at the time of displaying that a detection object 10 exists within a detecting section 1 by a display euipment 50, the fluctuation state is not transmitted to a display control circuit. When the electric field strength comparing circuit judges that reception is alternately executed by the receivers 30a and 30b owing to the fluctuation of reception electric field strength at the time of displaying that the fluctuation object 10 does not exist within the detection section 1, the data is not transmitted to the display control circuit. Since the fluctuation does not occur when the detecting object 10 completely enters the detecting section 1, it is displayed that the detecting object 10 exists within the detecting section 1 in the display equipment 50 by a timer after a fixed time elapses.</p> |
