Design and Analysis of a Wideband Intra-Body Communication System

• Main Authors: Yuhwai Tseng, 曾煜輝
• Other Authors: Chauchin Su
• Format: Others
• Language: en_US
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/91481792219199173871

博士 === 國立中央大學 === 電機工程研究所 === 98 === A square test waveform replaces a series of different sinusoidal test waveforms to simplify measurements of the characteristic of the human body channel in the Electrostatic Coupling Intra-Body communication (ESC IBC) system. The human body channel is analyzed and determined by adopting an equivalent circuit model comprising the biological impedance of body parts. Additionally, the system frequency response is extracted by applying de-convolution on square test waveforms. Then, we measure and evaluate the electrical impedance of a human body from a system perspective. Measurement and simulation results demonstrate the feasibility of the proposed approach for evaluating the electrical impedance of the human body. The evaluated bioelectrical impedances with the equivalent circuit model of the human body were utilized to replace the channel of the ESC IBC system. The simplified measurement methodology that is based on the de-convolution on a square test stimulus was employed to measure the transmission characteristic of the ESC IBC channel. Then, a certain model mapping had been done by using battery-powered square waveform generator to mimic the channel model with physical metal wire as the ground return loop to the one that uses the environment as the ground return loop in the ESC IBC system. The proposed channel model is then verified using de-convolution on square waves and spectrum analysis. Results show that the proposed model and measurement methodology are valid for up to 22.5 MHz which allows a data rate of more than 10 Mbps. Finally, a simplified signal and noise model, and unit step function are presented respectively to analyze the contribution of the high pass filter function to wideband digital transmission in ESC IBC system since the maximum high pass 3 dB poles that can ensure favorable signal quality in a baseband Intra-Body communication system. The experimental eye diagram gives a data rate of more than 16 Mbps in a digital baseband transmission of the ESC IBC system.