Signal recognition and classification for identifying a fire
US5237512A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 20, 1991 |
| Grant date | Aug 17, 1993 |
| Priority date | — |
| Expiry date | Nov 20, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V10/40
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An apparatus and method for sensing electro-magnetic radiation and analysing the resultant electrical signal waveform, in order to determine whether the radiation originates from a fire condition, monitors variations in the signal waveform over a predetermined period of time. The amplitudes of the successive transitions in the waveform and the elapsed time between the transitions are measured. Two two-dimensional matrices are produced. The first of these is made up of a plurality of co-ordinate points each corresponding to a respective pair of successively occurring signal transitions. The position of each such point in the matrix is dependent on the respective amplitudes of the two transitions making up each pair. The second matrix is also made up of a plurality of co-ordinate points each corresponding to a respective pair of the signal transitions. In the second matrix, however, the position of each point within the matrix depends on the amplitude excursion and the elapsed time between the two transitions of each pair. The matrices thus produced are compared with predetermined matrices corresponding, for example, to predetermined fire conditions or false alarm conditions, whereby…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.