建立了基于人体多层组织结构的人体通信系统模型。利用人体的波导效应,直接将电磁信号耦合到人体。采用FDTD算法从电磁场与人体交互作用的角度仿真了人体通信的信道特性。结果表明,450~750 MHz和1~1.2 GHz是人体通信的两个最佳通信频段;合理选择收发机的结构,包括电路板尺寸、电极距离和大小,可以有效提高通信效率。分析人体通信电场的传输机制发现,信号沿着人体表面向四周爬行,因此接收机放在人体表面的任何一个位置均可接收信号。
A human body communication system is developed based on the multiple-layer biological tissues of the real human body.In this system,the high-frequency electromagnetic wave is directly coupled to human body,which is treated as waveguide.An electromagnetic simulation method of FDTD is used to simulate the body channel characteristics from the aspect of interaction between electromagnetic field and human body.The results show that 450~750 MHz and 1~1.2 GHz are the best communication frequency bands for the human body communication.By selecting a proper transceiver structure,such as the transmitter length,the size and the distance between two electrodes of transmitter,the communication efficiency can be effectively improved.It is noted that the transmission mechanism of the human body communication lies in that it creeps along the surface of human body to all directions so that the signal can be received at any position on the body.