基于快速傅立叶变换的阻抗数据处理方法研究

摘要

The fast fourier transform (FFT) arithmetic was applied to remove the random noise in the impedance spectra of the piezoelectric sensor. It was shown that the FFT arithmetic is a simple and efficient method to decrease the noise level of the piezoelectric sensor. By using suitable parameter, excellent filter and smooth results were obtained. The new arithmetic was applied to measure the resonant frequency shifts of the piezoelectric sensor during surfactant adsorption process. The parameters related to the adsorption of nonionic surfactant, TX -114, on polystyrene film were estimated.%　　根据阻抗频谱的特点，提出了基于快速傅立叶变换法(FFT)抑制压电传感器随机测量噪音的方法，结果表明，利用该法能对阻抗频谱进行有效平滑处理，滤噪效果明显，所得频率抗干扰能力大大增强。将该方法用于水中基线噪音消除，证明了其相对于其它方法的优越性。结合该文提出的数据处理方法，利用压电传感器研究了非离子表面活性剂 TX-114在聚苯乙烯(PS)表面的吸附性能，得到了相关动力学、热力学参数，进一步证实了 FFT 法的可行性