| 摘要 |
PROBLEM TO BE SOLVED: To provide the missing prevention system for the communication portable terminal equipment by which it is informed accurately and quickly when the communication portable terminal equipment is missing by preventing malfunction of an alarm device due to other radio wave than a radio wave from a destination communication portable terminal equipment or other noise or the like. SOLUTION: When a communication portable terminal equipment 10 sends periodically a signal to an alarm device 25, the alarm device 25 is not in operation and when the communication portable terminal equipment 10 does not periodically send a signal to the alarm device 25, the alarm device 25 is in operation to inform missing of the communication portable terminal equipment 10. Since the alarm device 25 confirms the destination communication portable terminal equipment 10, malfunction by other radio wave than a radio wave from a decided destination communication portable terminal equipment 10 and other noise or the like is prevented and when the communication portable terminal equipment 10 is missing, the alarm device 25 informs it accurately and quickly.
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