電極主要的功能在於減少人體與電路之間的接觸阻抗，然而電極並非完美的導體，電極與皮膚介面中的阻抗會造成量測結果的偏差，在生醫量測的應用中，若是忽略這些誤差，可能會誤判受測者真實的生理狀況，因此有必要建立一套方法來補償電極所造成的誤差。本研究目的在於建立一套通用的補償流程，讓各種不同的電極都能透過這個流程建立補償電路，消除電極所造成的誤差，增加生醫量測的準確性。實驗結果顯示：同款式的電極之間的阻抗差異程度卻非常大，所以每個電極所造成的扭曲必須透過其對應的補償電路來補償，另外，補償電路在特定的頻帶內能夠精準地補償電極的電容性所造成的扭曲，然而，此電路的實作成果與模擬結果在低頻的部分仍有些微的誤差。

The main function of electrodes is to reduce the contact impedance between human bodies and electric circuits. However, electrodes are not perfect conductors, so the impedance of the skin-electrode interface will distort the measurement results. In biomedical measurement applications, neglecting this distortion can result in misjudgment about the actual physiological condition of subjects. Thus, it is necessary to establish a method to compensate for the distortion caused by electrodes. In this research, we establish a universal process of signal compensation for all types of electrodes. A specific compensation circuit for a certain type of electrode can be established through this process to eliminate the distortion caused by the electrodes and to increase the accuracy of biomedical measurements. The results of this study reveal that there are huge differences between electrodes of the same type, so the distortion caused by electrodes should be addressed on a case-by-case basis. A compensation circuit can accurately compensate for the distortion caused by the capacitance of electrodes in specific frequency bands. However, there remains a slight difference in the frequency response at low frequencies between the simulation and actual circuit.

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