作物生长信息获取多光谱传感器设计与试验

为了实时、快捷、无损获取农作物生长信息,根据作物生长指标的光谱监测机理,研制了一种四波长作物生长信息获取多光谱传感器.采用光学滤波技术提高了光辐射信息输入信噪比,依据作物冠层特征及田间作业环境实际要求,设计了适宜的探测镜头结构参数,确保了多光谱传感器灵敏度与分辨效果,应用T型电阻积分网络搭建了微弱光谱信息放大电路.通过标定,获得了多光谱传感器与FieldSpec Pro FR2500型光谱仪的关系模型,决定系数分别为0.8028、0.8068、0.8185、0.8900.对小麦的试验结果表明,该传感器的平均测量误差分别为5.6％、4.6％、1.4％、4.5％.该传感器能够较好地实现作物冠层反射光谱的实时在线检测,为作物生长监测设备的研发提供了有力支持.

Design and Experiments of Multi-spectral Sensor for Rice and Wheat Growth Information

To access the growth information of crops fast, non-destructively in real-time, a four band multi-spectral sensor of crop was developed based on spectral monitoring mechanism of crop growth indicators. Optical filtering technique was used to improve the input signal to noise ratio of optical radiation. Based on crop canopy characteristics and operating environment in the field, the suitable structure parameters of detection lens was designed, ensuring that sensitivity and resolution effect of multi-spectral sensor. The weak spectral information amplifying circuit was built by T-type resistance network. Through calibration, the relational model of multi-spectral sensor and FieldSpec Pro FR2500 spectrometer was obtained, the coefficient of determination of which was 0.8028, 0.8068, 0.8185 and 0.8900 respectively. The wheat test results showed that the average measurement error of the sensor were 5.6%, 4.6%, 1.4% and 4.5% respectively. The sensor could realize real-time online tests of crop canopy reflectance spectra to provide strong support for the development of the crop growth monitoring equipment.