Application And Research Of Key Technologies Of Wearable Network Based On Human Body Communication

Human body communication technology is a new communication technology with subversive significance.It is a kind of short-range wireless communication technology using human body as the transmission medium.human body communication can be divided into two coupling modes: current coupling mode and capacitance coupling mode.In human body communication,electrodes are used to couple signals to the body.Compared with traditional wireless communication,this method has lower power consumption and security.At present,the research on human body communication mainly focuses on the point-to-point channel modeling and transmission path loss.At the same time,the research on electromagnetic safety evaluation of human body communication equipment is relatively less.With the development of 5g technology,Internet of things and other technologies,human body communication area communication composed of multiple nodes has become the focus of research.Therefore,this paper mainly focuses on the modeling and analysis of the application scenarios of human body communication,and studies the electromagnetic absorption rate of human body communication device when communicating.Finally,a set of transceiver based on human body communication technology is designed.Based on the theory of electromagnetic wave,this paper aims to explore the electromagnetic effect of human body itself,from both theoretical and practical aspects.This research has a positive role in enriching the theory of human body communication technology,and has a strong practical significance for the application of wireless communication technology in wearable biomedical devices.The specific contents of this study are as follows:Firstly,based on the electromagnetic characteristics of human body,combined with the electromagnetic analysis method,human body communication is divided into two parts: human body electromagnetic characteristics and human body electromagnetic absorption characteristics.The basic concept and specific analysis flow of human body communication are described.The working frequency and penetration depth of human body communication are further analyzed by establishing the human body model of non-uniform medium in electromagnetic simulation analysis software.Starting from the method of electromagnetic analysis,the electromagnetic simulation analysis of human body is introduced,and the human body model with non-uniform medium is established.The simulation results of electrode size,coupling position and different distance are obtained by the model.The propagation characteristics and channel fading results are analyzed by comparing the experimental results.Secondly,for human body communication technology,electromagnetic safety can not be ignored.In this paper,through the limit of electromagnetic absorption rate,combined with the existing measurement and analysis means.Firstly,the feasibility of the method is studied with rat model,then the electromagnetic absorption rate of the human body model based on medical image data is analyzed,which verifies the high security of human body communication technology.Finally,based on the first two parts of the electromagnetic characteristics of human body and the simulation results of electromagnetic absorption rate,a simple human body communication transceiver is designed and its basic performance is tested.The innovation of this paper includes:1.The scene of multi-node human body communication is modeled,the maximum likelihood estimation and red pool principle are used for statistical analysis,the channel fading characteristics are analyzed with different fading models,and the mutual interference of multi-person is studied.The results show that human body communication technology has good effect in multi-node scene.2.The electromagnetic absorption rate of human body in the use of human body communication is studied by using the finite difference time domain method.The results show that the electromagnetic radiation of human body communication technology is far lower than the electromagnetic radiation standards at home and abroad.That is to say,human body communication technology has good propagation and security characteristics.It provides reliable data support for human body communication research.