基于虚拟信号处理平台的差分式中红外甲烷检测系统  

Differential mid-infrared methane detection system based on virtue signal processing platform

作　　者：吕瑞红[1] 宋楠[1] 宋芳[1] 叶玮琳[2] 郑传涛[1] 王一丁[1] 

机构地区：[1]吉林大学电子科学与工程学院集成光电子学国家重点联合实验室吉林大学实验区,吉林长春130012 [2]汕头大学工学院,广东汕头515063

出　　处：《光电子．激光》2013年第7期1350-1356,共7页Journal of Optoelectronics·Laser

基　　金：国家科技支撑计划(2013BAK06B04);国家自然科学基金(61077074);吉林省科技发展计划(20120707);长春市科技发展计划(11GH01);汕头大学科研启动基金(NTF12022);汕头大学青年科研基金(YR12005)资助项目

摘　　要：利用上位机及Labview工作平台数据处理能力强的优势,实现了一种针对甲烷(CH_4)气体的双通道差分式中红外检测系统。采用IRGJ型双通道传感器(英国E2V公司,3.31μm和3.90μm)检测气体浓度变化,利用Labview和数据采集(DAQ)卡(PCI6 221)实现对探测器输出信号的采集和处理,采用二阶巴特沃斯数字滤波器滤除噪声以提高信噪比(SNR),对系统硬件和软件进行了集成。系统具有信号采集、滤波、幅值提取、浓度计算、存储及网络发布等功能。配备了不同浓度的CH_4气体样品,开展了标定实验,并测量了系统的精度、稳定性和检测下限等指标。实验结果显示,系统对CH_4气体的测量范围为0～5%,对9种气体样品的检测误差均小于6%。受传感器自身光程的限制,系统的检测下限约为60×10^(-6)。对浓度为2 000×10^(-6)(0.2%)的气体进行了长达4 h的浓度检测,除个别突变点外,检测的最大误差小于10%。由于数据处理能力强,系统功能不受资源限制并可任意扩展。By means of strong data processing ability of personal computer （PC） and Labview platform,a mid-infrared dual-channel differential CH4 detection system is designed and realized. A dual-channel IR- GJ sensor （purchased from E2V Company,British,3.31 μm and 3.90 μm） is utilized to detect concen- tration change,Labview and data-acquisition （DAQ） card （PCI6221） are mainly used for signal sampling and processing,a digital second-order Butterworth filter is designed via the platform to increase signal to noise ratio （SNR）, and finally the system is integrated with both hardware and software. The developed system possesses functions including signal acquisition,filtering,amplitude extraction,concentration call- bration,information storage and website announcement. CH4 samples with different concentrations are prepared,calibration experiments are carried out,and detection precision,stability and detection limit are measured. Experimental results reveal that the measuring range on CH4 is 0-5% the maximum detection error of this system on 9 gas samples is less than 6%. Because of limitation of path-length of the sensor, the detection limit is about 60 ppm. Four hours detection on a gas sample with a concentration of 2 000 ppm shows that the detection error is less than 10%. Due to high data processing ability and powerfulfunctions unconstrained by system resource, this system shows certain applications in the detection on gas samples under laboratory environment.

关 键 词：光电检测 中红外气体检测 LABVIEW 数据采集(DAQ)卡 

分 类 号：TN21[电子电信—物理电子学]