红外火焰探测信号的特征提取研究

在设计红外火焰探测器时,特征值的选取是识别火焰的关键因素.分别对火焰和高温热源信号的过零点与其对应时间关系进行研究,提出将信号过零点与其对应时间拟合直线的线性度作为区别火焰与高温干扰的一个特征值.通过对相同环境下,不同大小的酒精灯火焰的过零点时间进行分析,发现利用拟合直线的斜率,可计算出火焰的频率;提出拟合直线的斜率可作为识别火焰的另一个特征值.实验结果表明:物质燃烧时,过零点与其对应时间的线性关系在一定范围内保持不变,用拟合直线的线性度和斜率作为识别火焰的特征值具有一定的可行性.

Study of feature extraction of infrared flame detection signal

In design of infrared flame detector,the selection of characteristic values is the key factor to identify the fire.Firstly,the relationship between the zero point and its corresponding time of flame and heat source are analyzed,linearity of fitting straight line about zero points and time is proposed to be a characteristic value to distinguish the flame and heat source.At the same time,based on the analysis on over zero points and time in different sizes of alcohol lamp flame,the frequency of flame can be calculated by the slope of the fitting straight line,so the proposed slope can be another characteristic value.Experimental results shows that within a certain range,linear relationship between over zero points and its corresponding time of the flame is invariable at certain range,then linearity and slope are proposed to be the characteristic values for flame recognition is feasible.