EP 0507025 A2 19921007 - Intruder detection arrangements and methods.
Title (en)
Intruder detection arrangements and methods.
Title (de)
Verfahren und Vorrichtungen zur Aufspürung eines Eindringlings.
Title (fr)
Arrangements et procédés pour la détection d'intrusion.
Publication
Application
Priority
GB 9107062 A 19910404
Abstract (en)
An intruder detection arrangement has a passive infra-red sensor (10) for detecting the presence of an intruder in a predetermined zone of protection and an IR anti-masking detection unit (20) for detecting the presence of masking material M in view of sensor (10). A signal processing circuit (30) is responsive to outputs from the sensor (10) and the detection unit (20) producing an intruder alarm signal in response to an output from sensor (10) and an anti-masking alarm signal in response to an output from unit (20). The signal processing circuit is arranged to cancel the anti-masking alarm signal in response to an output from sensor (10) produced after the output from unit (20) that gave rise to the anti-masking alarm signal. <IMAGE>
IPC 1-7
IPC 8 full level
G08B 13/19 (2006.01); G08B 29/04 (2006.01)
CPC (source: EP)
G08B 13/19 (2013.01); G08B 29/046 (2013.01)
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
EP 0507025 A2 19921007; EP 0507025 A3 19930224; EP 0507025 B1 19970730; DE 69127068 D1 19970904; DE 69127068 T2 19980115; GB 9107062 D0 19910522
DOCDB simple family (application)
EP 91307782 A 19910823; DE 69127068 T 19910823; GB 9107062 A 19910404