阻抗量測的技術被廣泛地應用在生物醫學領域的研究上，例如：用於測量即時心室體積與壓力變化的電導心導管。其原理是將測量到的阻抗值轉換成體積。體積與壓力之間的關係呈迴路狀，而此心室之血壓-血量迴路分析圖(Pressure-Volume Loop Analysis)正是研究者或是醫師一個評估心臟功能的工具。
我研究的主要目標是開發一套電導心導管的即時心室血壓-血量的量測系統。不同於過去傳統類比式的儀器，此系統採用了德州儀器所製造的高速的DSP晶片TMS320F2812作為信號處理的核心，取代過去使用大量類比元件的實現方式。之後再將此晶片與周邊的電路整合在一起，完成整套儀器。除此之外，使用資料擷取卡擷取資料，並利用LabView撰寫結果顯示介面，將前端系統處理的信號結果，即時地顯示出來。
另外為了驗證此系統，設計另外兩項儀器裝置，並且實際地去作活體實驗。 (1)信號模擬器：產生類似於測量到的心室電壓信號，以當作系統開發階段的一個測試工具。其目的主要是用來評斷與測試系統的頻寬，與是否能正確運作達到需求。(2)氣球式心室電導模擬裝置：用以模擬跳動中的心室及電導心導管實際測量時的心室環境，測試此系統對於實際的測量環境，能否正確工作。(3)老鼠活體實驗：驗證此系統是否真的能夠應用在實際的老鼠活體實驗上。
最終，由上述的測量結果來看，驗證此系統的確能夠正確地處理信號與運作。

Electrical impedance measurement technique is widely used in biomedical researchers and applications, such as a conductance catheter. The conductance catheter is used to measure real-time ventricular impedance, and then the measured impedance is converted to ventricular volume. While incorporating with pressure signals, a real-time ventricular pressure-volume loop plot can be obtained, which is a standard tool for researchers and doctors to evaluate the cardiac functions.
The main purpose of my research is to develop a real-time measurement system for the conductance catheter. Instead of traditional instrument designed with analog elements for processing, a high speed DSP chip, TMS320F2812 made by Texas Instrument, is used to be the core for digital signal processing. Besides, peripheral analog circuits are needed for signal sensing. Moreover, a graphic user interface, implemented by LabView and a data acquisition card, is designed to illustrate the measurement result immediately.
Next, some other equipments are designed to verify the system and finally the in-vivo experiment is performed. (1) An emulator that can mimic the special measured voltage signals is constructed. During the system development stage, the emulator is served as a benchmark to test the functionality and bandwidth of the system. (2) A ventricle-imitated environment is constructed that can test if the system can work for real situation. (3) In vivo Rat experiment that can test the system whether it can work for in-vivo measurement.
According to the measurement results, the designed system does work well.

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