用于电流耦合型人体通信的有限元模型探究

An Investigation on Finite Element Model of Intra-Body Communication by Galvanic Coupling

目的:研究电流耦合型人体通信(Intra-Body Communication,IBC)的传输特性。方法:以人体通信中最常使用到的部位-人体手臂为着眼点,合理抽象并得到手臂的等效数学模型,进而使用有限元方法探究人体中电流分布机理。另外,通过给模型施加不同形式下电信号,比较分析人体的信道特性。结果:①在安全阈值内,注入人体电流大小对信号衰减影响不大;②信号衰减随着发送电极尺寸的增大而减小;③收发电极间距离愈大,信号衰减愈大;④人体通信电流主要流经肌肉层,不过随频率增大,集肤效应明显,在骨中的比例很小,足以忽略。结论:本文提出的人体手臂等效有限元模型,可以对电流耦合型人体通信的通信机理展开分析。

Objective：To investigate the transmission characteristics of human body as the medium of Intra-Body Communication.Methods： For the galvanic coupling IBC,the forearm,is the main object appeared in IBC,which was abstracted to an equivalent phantom to investigate the mechanism of current flowing in the human body based on the finite element methods.Different types of electric signal were applied into the model to analyze and compare the channel characteristics of human body.Results： ① Under the safe threshold, different values of injected current have little effect on the signal attenuation; （2） The signal attenuation decreases with the increasing in the size of the transmitter electrodes; （3） The increasing distances between the transceivers lead to a higher attenuation; （4） The current mainly flows in the muscle layer, which is small enough to neglect in bones,Skin effect is more evident along with the frequency elevation. Conclusion： The finite element model of human＇s forearm prompted in this paper, is feasible and valid to analysis of communication characteristics of galvanic coupling IBC.