红外气体传感器信号调理及数据处理

Signal conditioning and data processing of infrared gas sensor

针对红外气体传感器易受外界光源、电磁等干扰影响,其输出信号中存在大量噪声而影响检测精度的问题,设计了一种红外气体传感器信号调理及数据处理电路。该电路采用硬件和软件相结合的方法,在硬件上设计了信号调理电路,在保证信号真实性的同时具有非常好的放大滤波功能;在软件上采用中位值平均滤波算法对信号进行处理,可有效克服信号中混入的噪声,且对周期性和热噪声产生的干扰也有很好的抑制作用。试验结果表明,该电路可有效滤除传感器中的大量噪声,准确提取有用信号,提高检测精度及稳定性,满量程精度可达0.54%。

In view of problems that infrared gas sensor is easy to be interfered by external optical source and electromagnetism,and its output signal is mixed with a lot of noise to affect detection precision,signal conditioning and data processing circuit of infrared gas sensor was designed.The circuit combines hardware with software.Signal conditioning circuit was designed in hardware,which has the extremely good enlargement filter function during meanwhile guarantees the signal authenticity.Way of median average filtering algorithm was used to process signal in software,which can effectively overcomes noise mixed in the signal and has good inhibitory action to the interference produced periodicity or thermal noise.The experimental results show that the circuit can filter out a lot of noise of sensor effectively and extract useful signal accurately,improve detection accuracy and stability of sensor and its full scale measurement precision may reach 0.54%.