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Simulation based on the finite-element (FE) method plays an important role in the investigation of intra-body communication (IBC). In this paper, a finite-element model of the whole body model used for the IBC simulation is proposed and verified, while the FE simulation of the galvanic coupling IBC with different signal transmission paths has been achieved. Firstly, a novel finite-element method for modeling the whole human body is proposed, and a FE model of the whole human body used for IBC simulation was developed. Secondly, the simulations of the galvanic coupling IBC with the different signal transmission paths were implemented. Finally, the feasibility of the proposed method was verified by using

Intra-body communication (IBC) is a technology that involves using the human body as a transmission medium for electrical signals [

To guarantee the safety of the human body, many IBC experiments were carried out by using simulation methods. Therefore, software simulation serves as an important method in the investigation of intra-body communication. The software simulation of IBC can be implemented by using the transfer function method [

In this paper, a finite-element model of the whole body model used for the simulation of the galvanic coupling IBC is firstly proposed and verified, while the FE simulation of the galvanic coupling IBC with the different signal transmission paths has been achieved. First, we discuss the theoretical foundation of the finite-element method for modeling human body. Secondly, the modeling of the whole human body and the corresponding electromagnetic parameters are described, and then the simulation of the galvanic coupling IBC with the different signal transmission paths are implemented and the corresponding potential distributions are discussed in detail. Finally, the feasibility of the proposed model is verified by using

The rest of the paper is organized as follows: Section 2 focuses on the geometry modeling and the corresponding parameters of the whole human body. The galvanic coupling IBC simulation conditions and the results discussion are presented in Section 3. Section 4 mainly verifies the feasibility of the proposed model by using

The coupling between electromagnetic signals and human body can be explained by the Maxwell equations and the boundary conditions. According to [

In the galvanic coupling IBC application, due to the fact that electronic signal is transmitted and received as electronic form, as a result, only the electric field is of interest [

Based on the equations mentioned above, the electronic signal transmission within the human body can be simulated by using the finite-element method, which is applied to solve the quasi-static volume conducting boundary problem by the numerical solution of the partial differential equations.

A human body part (such as the upper arm) can be abstracted as a concentric cylinder with multiple layers in the simulation of the interaction between the electromagnetic signal and the human body [

The electromagnetic parameters are essential to achieve the IBC simulation based on the finite-element method. The electromagnetic characteristics of human tissues (such as skin, fat, muscle and bone) can be described by their conductivity and relative permittivity. On the other hand, the conductivity and relative permittivity of the different tissues have been investigated by Gabriely _{r}

The simulations of the galvanic coupling IBC with different signal transmission paths were carried out using the proposed FE model. The simulations were produced with the electromagnetic analysis package (EMAG) of ANSYS, while the mesh sizes were set between 400,000 and 450,000 elements. To isolate the human body model against air, the normal component of the electric field corresponding to the boundary between the skin and the air was set to zero [_{r}

We can also find from

To verify the feasibility of the proposed FE model,

In the investigation of IBC, signal attenuation can be determined by using 20·log_{10}(_{r}_{t}_{r}_{t}_{r}_{t}_{r}_{t}

Similarly, we can find from

On the other hand, due to the fact that both the L1T1 path and the L1A1 path consist of leg and torso, as shown in

The development of a FE model of the whole human body and the investigation of the potential distribution corresponding to different signal transmission paths will help to clearly disclose the signal transmission characteristics of the human body. In order to meet this requirement, a finite-element method for modeling the whole human body is proposed in this paper, while both the simulations of the galvanic coupling IBC based on the whole human body and the corresponding

The work was supported by the National Natural Science Foundation of China (60801050), the Excellent Talent Fund of Beijing, China (2011) and the Innovation Fund of Shanghai Aerospace Science and Technology, China (2012). The authors are grateful to the Institute of Optics, University of Rochester (Rochester, NY, USA) for their help.

The 3-D view (

The modeling of head and neck.

The torso of the whole body model.

The electrode distribution over the whole body model.

The potential distribution when signal transmits from T1.

The real part (

The real part (

The measurement setup.

The simulation results and the measurement results of the A1A2 path (

The simulation results and the measurement results of the LIT1 path (

The influences of signal transmission distance on the simulation results (

The conductivities and relative permittivities.

10 | 4.0E−03 | 3.0E−02 | 3.5E−01 | 2.0E−02 | |

20 | 7.0E−03 | 3.0E−02 | 3.5E−01 | 2.0E−02 | |

50 | 1.2E−02 | 2.9E−02 | 3.7E−01 | 2.0E−02 | |

100 | 4.0E−02 | 2.8E−02 | 3.9E−01 | 2.0E−02 | |

200 | 9.0E−02 | 3.5E−02 | 4.4E−01 | 2.2E−02 | |

500 | 1.3E−01 | 4.5E−02 | 5.0E−01 | 2.5E−02 | |

1,000 | 2.0E−01 | 4.5E−02 | 6.0E−01 | 2.5E−02 | |

2,000 | 2.5E−01 | 4.6E−02 | 6.3E−01 | 2.8E−02 | |

3,000 | 2.8E−01 | 4.6E−02 | 6.5E−01 | 3.3 E−02 | |

5,000 | 3.5E−01 | 4.7E−02 | 6.8E−01 | 4.0E−02 | |

| |||||

_{r} |
10 | 3.0E+04 | 1.0E+03 | 3.0E+04 | 5.5E+02 |

20 | 2.7E+04 | 6.0E+02 | 2.0E+04 | 4.8E+02 | |

50 | 2.3E+04 | 3.0E+02 | 1.2E+04 | 3.4E+02 | |

100 | 2.0E+04 | 1.0E+02 | 8.0E+03 | 2.5E+02 | |

200 | 1.4E+04 | 6.5E+01 | 6.3E+03 | 2.1E+02 | |

500 | 8.0E+03 | 4.0E+01 | 4.0E+03 | 2.0E+02 | |

1,000 | 3.5E+03 | 3.0E+01 | 3.0E+03 | 1.6E+02 | |

2,000 | 1.5E+03 | 2.6E+01 | 2.2E+03 | 1.3E+02 | |

3,000 | 8.2E+02 | 2.4E+01 | 1.2E+03 | 1.0E+02 | |

5,000 | 5.0E+02 | 2.0E+01 | 4.0E+02 | 6.0E+01 |