宽频带生物阻抗测量系统的研制

本文针对常规生物阻抗测量存在测量频率范围窄、调节操作繁琐等问题,采用DDS数字直接合成频率芯片和宽带乘法器芯片为核心器件,利用向量分析法原理,设计了一种可在20 Hz～20 MHz范围频率内对生物电阻抗进行快速测量和分析的系统,给出了阻抗测量的原理、电路的构成及设计方法.对试制的样机进行了测试,并将结果与安捷伦4294A型阻抗分析仪的测量结果进行了比较.测试结果表明,该系统能在宽频带范围内快速测定阻抗参数,可广泛应用于生物医学的实验和研究工作.

Study on wideband bioelectrical impedance measurement system

To solve the problems like narrow frequency band and complicated adjusting operation etc exist in the normal bioelectrical impedance measurement, By using vector analysis principle we present a fast measuring and analyzing system for bioelectrical impedance within the frequency between 20 Hz-20 MHz with DDS chip and wideband multiplier chip as the core device, and the impedance measurement principle as well as the constitute and design methods are also given. Comparing the test result of prototype machine with that of Agilent 4294A device, we can find that this system can take fast measurement of impedance parameter within the wideband, and can be widely used in the domain of biomedical research and testing.