多频多段人体生物电阻抗测量系统

人体生物电阻抗是人体体成分的重要组成部分,在一定程度上反映了人体组织的生理状况。基于此,设计了一套基于八电极的多频多段人体生物电阻抗测量系统。测量系统由单片机系统、正弦交流激励电流源、有效值检测电路等组成,实现了5～500 kHz频率范围的左右上下肢及躯干的5段测量。测试结果表明,测量系统实现了人体生物电阻抗的幅值和相位的高精度测量,幅值相对误差小于0.7%,相位绝对误差小于0.8°。

A Bioelectrical Impedance Measurement System Based on Multi-Frequency and Multi-Segment Technology

Bioelectrical impedance is an important composition of human body,and reflects the physical conditions of human tissues to some extent.Based on this,a multi-frequency and multi-segment bioelectrical impedance measurement system is designed on the principle of eight electrodes.In fact,the system,which consists of MCU system,sinusoidal excitation current source,RMS-to-DC circuit and etc,has achieved the impedance measurement of the extremities as well as the trunk under the frequency ranged from 5~500 kHz.Experiment results show that the system finally realizes high-accuracy measurements of amplitude and phase of bioelectrical impedance with the result of a relative error of magnitude which is less than 0.7% and an absolute error of phase which is less than 0.8°.