EP 0547458 B1 19970521 - Radio alarm system
Title (en)
Radio alarm system
Title (de)
Funkalarmanlage
Title (fr)
Système radio d'alarme
Publication
Application
Priority
DE 4141035 A 19911212
Abstract (en)
[origin: EP0547458A1] A radio alarm system is described which consists of a central station (1) with a receiving unit (2), a computer unit (3) and a transmitting unit (8) and of at least one detector (4) with a transmitting unit (7), computer unit (6), a signalling unit (5) and a receiving unit (12). The receiving units of the central station and of the detector are tuned to the respective transmitting units. In the case of an event, the transmitting unit (7) of the detector (4) outputs a first radio signal to the central station which is received by its receiving unit (2) and in the latter initiates, in a manner for generating a request signal for repeating the first radio signal from the detector (4), that a random-number generator generates a code which is stored in the memory of the computer unit (3) and is used for processing the radio signal which is radiated by the central station. The radio signal is received by the detector (4), forwarded to its computer unit which prepares the repeated signal using the code also received from the central station (1) and which is then radiated by the transmitting unit (7). The receiving unit (2) of the central station (1) receives the repeated signal and forwards it to its computer unit (3) in which the received code is filtered out and compared with the code stored in its memory. If the received code deviates from the stored code, a fault alarm is generated by the central station whereas when both codes are identical, the signal is processed in accordance with its content and the state of the central station. <IMAGE>
IPC 1-7
IPC 8 full level
G08B 25/10 (2006.01); G08B 29/16 (2006.01)
CPC (source: EP)
G08B 25/10 (2013.01); G08B 29/16 (2013.01)
Designated contracting state (EPC)
AT CH ES FR GB LI
DOCDB simple family (publication)
EP 0547458 A1 19930623; EP 0547458 B1 19970521; AT E153466 T1 19970615; DE 4141035 C1 19921217; ES 2101788 T3 19970716
DOCDB simple family (application)
EP 92120806 A 19921205; AT 92120806 T 19921205; DE 4141035 A 19911212; ES 92120806 T 19921205