PKB/Akt脉冲电流激励模式下阻抗测量的原理与实现

Mechanism and implementation of impedance measurement excited by current pulses

目的 :探讨脉冲电流激励模式下测量生物电阻抗的原理及其实现 .方法 :通过定时器、模拟开关、采样保持放大器、A/D板等设计并实现脉冲激励阻抗测量系统 .结果 :系统成功测量到头部血流变化信号 .结论 :与正弦激励的阻抗测量方法相比 ,脉冲电流激励模式可以提供一种电流负荷小 ,信噪比高 。

AIM: To study the mechanism and implementation of current pulse exciting impedance measurement of bio tissues. METHODS: An impedance measurement system was designed and implemented by timer, analog switch, sample and hold amplifier and A/D board. RESULTS: The blood pulsation of head was measured successfully. CONCLUSION: Compared with the continuous sine wave exciting mode used in the measurement of impedance, current pulse exciting mode can offer much lower current load to bio tissues, higher signal to noise ratio and better penetrability.