人體通道傳輸特性與設計人體通道傳收器

Characteristics of the Human Body Channel and Design the Human Body Channel Transceiver

林致佑(Chih-Yu Lin)

指導教授 ： 鍾菁哲

國立中正大學/工學院/資訊工程學系/碩士(2015年)

摘要

近年來，半導體技術結合生物醫學相關應用的穿戴式裝置及個人醫療照護裝置越來越流行。隨著現代移動通信設備已經成為人類生活中不可分割的一部分，有一項全新類型的通信協定被提出，稱為人體區域網路(Body Area Network, BAN)。BAN 可以提供各個散佈在人體周圍間的穿戴式或植入式的感測裝置所需要的連結。然而，傳統的電子醫療裝置，像是心電圖、肌電圖、聽診器等等的體積都偏大，並且需要實體的電線來傳輸資料。再者，利用射頻技術來傳收數據(像是藍芽、ZigBee)具有許多潛在的問題，例如低傳輸率、高功率消耗、以及容易受到其他同時使用相同頻段使用者的干擾等等。因此，我們利用人體當成一項傳輸媒介來傳收資料。比起傳統的無線傳輸應用，人體通道傳輸有著更省電及方便攜帶的好處。但是可能會受到人體天線效應的影響，外界的雜訊會被人體皮膚吸收，進而干擾到訊號的傳輸，增加了接收資料的困難度。
本論文首先針對人體通道傳輸的特性進行大規模的量測與分析，並且根據量測的結果來建立人體通道模型。最後，根據已經建立好的人體通道模型來設計人體通道傳收器。為了提高整合度，我們將前端電路的放大器與Schmitt trigger整合成一塊測試板來進行量測。量測的距離分別為1公分，40公分，以及140公分。量測的頻率範圍從1 MHz到80 MHz。另外，我們也針對收到訊號的jitter大小進行量測。
最後，根據量測結果所建立的模型，本論文設計了符合模型的人體通道傳收器。在傳送端部分，利用NRZI編碼的資料會直接被傳入人體通道中。在接收段部分，從人體接收的訊號會先經過前端電路測試板放大、並且回復成方波。再透過時脈資料回復電路來回復成原始資料以及時脈。

關鍵字

資料回復 ； 人體通道特性 ； 人體通道傳輸 ； 傳收器

並列摘要

In recent years, the wearable devices or personal healthcare devices for biomedical applications to build up the body area network (BAN) become more and more popular. Traditional electronic medical devices such as ECG, EMG, thermometers, and sphygmomanometers are quite large and require wire line connection. Therefore, human body communication (HBC) uses the human body skin as a transmission medium to replace wire line connection. As compared to wireless transmission methods, HBC is more stable and has less power attenuation. Furthermore, it is almost insensitive to the motion of the human body. However, the body antenna effects cause interferences in human body channel communication. Moreover, the transmission distances, signal frequencies, and power attenuations must be considered in building up a human body channel model.
In this thesis, the human body channel characteristics are measured by an analog front-end (AFE) PCB board. The AFE board consists of a voltage gain amplifier (VGA) and a Schmitt trigger. The measured transmission distance is 10 cm, 40 cm, and 140 cm. The measured frequency ranges from 1 MHz to 80 MHz. In addition, the jitter of the received signal is also measured to build up a human body channel model.
Finally, a wideband signaling (WBS) transceiver is proposed according to the measured human body channel characteristics. In the transmitter part, the NRZI-encoded data are sent directly to the human body channel. In the receiver part, after an AFE board amplified the received signals and recovered them back to digital waveform, a clock and data recovery (CDR) circuit recovers the signals and clock with jitter and frequency drift tolerance.

並列關鍵字

Human Body Channel Characteristics ； CDR ； HBC ； BCC

參考文獻

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