植物微弱电信号在线采集系统的设计

Design of Online Measuring System of Plant Electrical Signal 

摘要:

植物电信号是细胞在生命活动中发出的电磁信号,由于其信号幅值为微伏级,在采集过程中,其有效信号很容易被噪声所淹没；依据植物电位信号的高阻抗源特性以及植物电位信号采集技术的特点,选择贴片电极作为测量植物表面电位信号的传感电极,有效降低了引导电极对植物的伤害和对植物电信号的干扰；采用AD8221芯片,设计了采集放大器电路用于采集植物电位信号,并搭建了植物电信号的采集系统,整个采集系统由放大电路、A/D转换电路、MCU、MAX232和计算机组成；以芦荟为实验对象,测得12 ℃时芦荟叶片电信号幅值的最大值是0.51 mV,最小值是-0.22 mV；结果表明该采集系统能够很好地采集植物电信号,为下一步的信号分析打下了坚实的基础。

Abstract:

Plant electrical signal is an electromagnetic signal produced by cell life activities, because its amplitude was the μV level, the effective signal is easy to be swallowed up by the noise.According to the high impedance of plant electrical signal and the characteristics of acquisition technology of plant electrical signal, the patch electrode was selected in this study, developed to acquisition circuit and constructed the plant electrical signal collection system, then the ideal plant electrical signal was obtained. The maximum amplitude of electrical signal is 0.51 mV, the minimum value is 0.22 mV at the 12℃.The experiment showed that this system could effectively collect the plant electrical signal by aloe. This has laid a solid foundation for analyzing the signal.