采用电场分割法的电流耦合人体通信等效电路模型  

Equivalent circuit model of galvanic-coupling intra-body communication using electric field segmentation method

作　　者：陈志英 张志强 龚赞 CHEN Zhiying;ZHANG Zhiqiang;GONG Zan(School of Electrical Engineering&Automation,Xiamen University of Technology,Xiamen 361024,China)

机构地区：[1]厦门理工学院电气工程与自动化学院,福建厦门361024

出　　处：《武汉大学学报（工学版）》2022年第1期71-77,共7页Engineering Journal of Wuhan University

基　　金：福建省自然科学基金项目(编号:2018J01565);厦门理工学院科研攀登计划项目(编号:XPDKQ18021);厦门理工学院高层次人才项目(编号:YKJ19016R)。

摘　　要：针对电流耦合人体通信信道传输特性缺少简单、快速、有效的理论分析方法,提出了一种基于电场分割的电流耦合人体通信等效电路模型。以人体手臂为对象,按轴向、径向与环向进行几何分割,再根据电导、电容定义及4阶Cole-Cole模型计算分割后各区域的等效阻抗,进而获得人体手臂的等效电路模型。利用回路电流法计算分析10 kHz~10 MHz频率下等效电路模型,结果显示人体手臂信道电压增益随频率、发送电极夹角增大呈上升趋势,而随信道长度增加呈下降趋势。最后,采用COMSOL Multiphysics建立有限元仿真模型,仿真结果表明在10 kHz~1MHz频率范围内其与等效电路计算结果误差较小,变化规律一致,有效证明了等效电路模型在低频电流耦合人体通信的适用性和正确性。This paper presents an equivalent circuit model of galvanic-coupling intra-body communication based on electric field segmentation aiming at the lack of simple,fast and effective theoretical analysis method to analyze current-coupled human body communication channel transmission characteristics.The human body arm is taken as researching object and it is divided into axial,radial and circumferential parts according to the current density directions.The equivalent impedances of the divided parts are calculated by using the conductance and capacitance definition and the fourth-order Cole-Cole model,and then the equivalent circuit model of human arm is achieved.Loop current method is used to calculate the equivalent circuit model with frequency from 10 kHz to 10 MHz.The results show that the voltage gain of the human arm channel is increasing with the frequency and the angle between the transmitting electrodes,and decreasing with the channel length.Finally,the finite element simulation model is established by COMSOL Multiphysics to validate the circuit model.The simulation result shows that the error is small and the change law is consistent with the equivalent circuit model in the frequency range of 10 kHz~1 MHz.It effectively proves the applicability and correctness of the equivalent circuit model in low-frequency galvanic-coupling intra-body communication.

关 键 词：电流耦合人体通信 电场分割法 等效阻抗 等效电路模型 信道电压增益 

分 类 号：R318[医药卫生—生物医学工程] TM133[医药卫生—基础医学]