Research Of Field Fire Detection System Based On Infrared Technology

With the development of social economy and the boom of urban population, huge constructions increase rapidly. However, the conflagrations happened recent years show that traditional fire protection design doesn't meet the demand of unusual situation especially for field fire detection. Usually the coverage of constructions in the field is extremely large and their structure is much more complicated than ordinary buildings, so it's hard to detect fire effectively. As a result, it increases the difficulty for firemen to put out the fire, meanwhile, it may brings wicked social influence, causes tremendous damage and even personnel casualty. Therefore, it is intensely necessary to research the field fire detection system.This paper mainly discusses the principle and method of fire detection. It first introduces infrared technology briefly, which explains why infrared technology is adopted in field fire detection system. Then, the principle and structure of pyroelectric infrared sensor are expatiated, with characteristic of the sensor detailed discussed. Finally, an field fire detection system is designed based on this type of sensor. The paper also discusses fire signal characters and basic algorithm to process the signal, nevertheless, traditional fire processing algorithm is not flexible enough, it always causes a lot of false alarm, so this dissertation researches an intelligent algorithm to deal with fire signal instead. In the paper, BP network is adopted to realize the fire identification algorithm, with network structure, training method and identification effect deeply investigated. A suit of automatic fire detection software upon Delphi 7SE with the ability to connect SQL Server 2000 is also developed, it has several major functions such us fire signal gathering, signal pre-processing, fire automatic detection, fire alarm information storing and querying, and so on. The result of experiment shows the system is quite efficient in identifying a great variety of fire, and this contributes a lot to the development of fire protection technology.