Document Type and Number:
Japanese Patent JPS5411826
Kind Code:
Y2
Abstract:
An alarm system utilizing electromagnetic waves for detecting a moving object comprising an antenna and a transmitter-reciever apparatus having an oscillation loop for detecting changes in the impedance of the antenna. An amplifier circuit amplifies an output signal from the transmitter-receiver apparatus, and an alarm device operatively connected to the amplifier circuit is operated by the amplified signal so that an alarm is produced in response to an object moving in the range of space covered by the electromagnetic waves radiated from the antenna. A plurality of video cameras may also be operatively connected to a plurality of such transmitter-receiver apparatus.
Application Number:
JP7123071U
Publication Date:
May 25, 1979
Filing Date:
August 09, 1971
Export Citation:
International Classes:
H01Q17/00; G01V3/08; G08B13/22; G08B13/24; G08B13/26; H01Q9/28; (IPC1-7): G08B13/22; H01Q9/28; H01Q17/00
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