为实现对生物阻抗信号在同一时刻,不同频率下的动态检测,本文对混频激励下阻抗信息的提取方法进行了研究,分析了DFT能量泄漏与栅栏效应对正弦信号测量结果的影响,提出了基于DFT和虚参考矢量的混频生物阻抗测量方法.通过仿真和实验,验证了虚参考矢量方法的补偿作用.实验表明,本方法可以通过测量不同频率下的人体阻抗,体现出呼吸、脉搏等信息在不同频率下的动态响应.
In order to obtain bio-impedance information in different frequency simultaneously, the bio-impedance measurement method in the condition of mixing frequency excitation is studied in this paper. The influence of energy leakage and fence effect of DFT to sine signal detection is analyzed,according to which the bio-impedance measurement technology based on DFr with virtual preference vector is presented. Finally, the compensation of virtual preference vector is certificated by the emulations and experiments. From the experimental results, the dynamic reaction of respiratory and sphygrnus in different frequency can be manifested according to the human impedance measurement.