| 摘要 |
PROBLEM TO BE SOLVED: To provide a wireless alarm device capable of surely transmitting an alarm without receiving jamming radio waves from a predetermined direction. SOLUTION: This wireless alarm device is so structured that sensors 10 for detecting alarm information in a monitoring area are connected thereto; and alarm information in the monitoring area detected by each sensor 10 is transmitted and received to/from a monitoring center 3 via a wireless communication means 2. The wireless alarm device is provided with: an antenna 12 for wirelessly transmitting the alarm information to the monitoring center 3; and jamming radio waves shields 13 (a-f) for shielding jamming radio waves transmitted to the antenna 12 so as to prevent the antenna 12 from receiving them. COPYRIGHT: (C)2005,JPO&NCIPI
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