Bidirectional, interactive fire detection system
First Claim
1. A bidirectional, interactive communication system, comprising a controller connected to transmit a series of signal groups sequentially over a pair of electrical conductors, wherein each signal group includes a plurality of pulses, and a plurality of transponders coupled to said conductors, at least one of said transponders having means for replying to the controller by selectively modifying a portion of at least one pulse transmitted by the controller and thus encoding information on said one pulse, which reply is terminated by the controller with an overriding simultaneous transmission,wherein the controller includes means for sampling the pulse modified by the replying transponder at regular intervals to decode the information encoded on said modified pulse, and for providing an answer signal denoting said information.
7 Assignments
0 Petitions
Accused Products
Abstract
A communication system useful for fire detection which transfers data/commands bidirectionally between a controller and connected transponders on a real time, interactive basis. This system makes possible accurate data recovery, whether a transponder has its output shorted, or although multiple transponders are replying and makes possible the remote determination and constant monitoring of transducer sensitivity, at the controller. The sensitivity can be adjusted remotely at the controller, and different transducers can have different thresholds simultaneously, which can be changed collectively or individually to different settings manually or automatically at the controller. The system transmits reference data for supervision of system accuracy. Compensation for long-term changes is provided for both transponders and reducers in this system.
-
Citations
42 Claims
-
1. A bidirectional, interactive communication system, comprising a controller connected to transmit a series of signal groups sequentially over a pair of electrical conductors, wherein each signal group includes a plurality of pulses, and a plurality of transponders coupled to said conductors, at least one of said transponders having means for replying to the controller by selectively modifying a portion of at least one pulse transmitted by the controller and thus encoding information on said one pulse, which reply is terminated by the controller with an overriding simultaneous transmission,
wherein the controller includes means for sampling the pulse modified by the replying transponder at regular intervals to decode the information encoded on said modified pulse, and for providing an answer signal denoting said information.
-
26. A bidirectional, interactive communication system, comprising a controller connected to transmit a series of signal groups sequentially over a pair of electrical conductors, wherein each signal group includes the same number of pulses, each pulse includes a high portion and a low portion, and a plurality of transponders coupled to said conductors, each of said transponders having means for replying to the controller by selectively modifying a low portion of at least one pulse transmitted by the controller and thus encoding information on said one pulse, which reply is terminated by the controller with an overriding, simultaneous transmission,
wherein the controller includes means for sampling the low portion of the pulse modified by the replying transponder at regular intervals to decode the information encoded on said modified pulse, and for providing an answer signal denoting said information.
Specification