為了能減少量測程序，且精準的量測及計算人身體各組成部份的平均阻抗值，我們使用方波解迴旋技術取代傳統使用弦波的量測技術，同時建構一個由人身體各部的生物性阻抗所組成的等效電路系統，然後從系統的觀點來量測及估算人身體的平均電子阻抗。除此之外我們從方波信號中解迴旋以粹取等效電路系統的頻率響應，並將此粹取值與模擬結果比對，結果顯示本文所提出用來估算人體平均阻抗的方法是可行的。 本文接著簡化上述所提出的人身體各部的生物性阻抗所組成的等效電路系統，應用在靜電耦合人體傳輸通信系統中，並依此簡化的等效電路建構了靜電耦合人體傳輸通信通道模型。同時使用電池電源以環型振盪器為架構的方波產生器，來量測靜電耦合人體傳輸通信系統通道的傳輸特性，以符合靜電耦合人體傳輸通信系統的通道環境。本文所建構的靜電耦合人體傳輸通信通道模型經由方波解迴旋及頻譜的分析驗證顯示，一個靜電耦合人體傳輸通信通道至少有22.5MHz的頻寬範圍，至少可供10Mbps以上的信號傳輸。 然後從前文所提出的靜電耦合人體傳輸通信通道電路簡化模型中，發現一個會隨著負載阻抗、人體本身及所處環境而變化的高通極點Ph3dB存在。這個高通極點衰減低頻的信號值並降低系統的信號與雜訊比。本文從信號與雜訊的行為模式上去分析高通極點Ph3dB 對系統的影響，在不同的Ph3dB下，透過模擬與量測系統的信號與雜訊比，獲得一個最佳的Ph3dB值在30kHz與40kHz之間。最後經由Xilinx FPGA實驗板的驗證顯示，在傳送電壓為3.3伏，信號功率消耗為560uW，至少有16Mbps的傳送速率。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.
