盲源分離處理於多離子感測系統之硬體架構設計實現

Blind Source Separation Processing on Multi-ion Sensing System with Hardware Structure Design Implementation

林為強(Wei-Chiang Lin)

指導教授 ： 鍾文耀

中原大學/工學院/電子工程研究所/碩士(2010年)

https://doi.org/10.6840/cycu201000685

摘要

近年來，水質監控是現代生活重要的議題，為了有效地辨別水中所含離子的種類，要如何有效地得知與辨別原始訊號之變化為何，因此應用到盲源分離技術的理論，將水中離子有效地辨別。
本論文研究重點主要在於實現於多離子感測盲源分離系統之硬體架構實現。在此論文主軸決定以離子濃度變化為實驗設計考量，並且以此實驗設計考量作為盲源分離技術改變之特徵；首先將前端離子敏感型場效電晶體搭配橋式讀出電路，得到之訊號有效地經過盲源分離系統辨別其原始訊號，得到其主要離子及干擾離子變化之特徵曲線。在硬體實現的過程中，根據整體系統讀出電路讀出電壓值關係，使用浮點數來設計，將演算法運算過程了解透徹後，進行行為式的硬體系統建置，將各式運算方法有效地實現在硬體上，並且使用各種Xilinx所提供之IP(Intellectual Property)來有效地縮短開發之時程，最後再利用元件可程式邏輯閘陣列（Field Programmable Gate Array, FPGA）進行整體系統之驗證，結果顯示此硬體架構已有效地實現得到原始離子訊號。

關鍵字

橋式讀出電路 ； 浮點數 ； 盲源分離技術 ； 離子敏感型場效電晶體

並列摘要

In recent years, water quality monitoring has become an important issue of modern life. For safe human consumption, it is necessary to determine the ion contents of water. Blind Source Separation (BSS) theory provides an effective means of ion identification.

This research focuses on the hardware implementation of BSS for multi-ion sensing application. The initial part of this work includes the acquisition of sample source signals as basis for BSS algorithm verification. In multi-ion chemical environment, the source signals correspond to the concentration of main ions and the concentration of interference ions. Experiments are conducted where the concentration of main ions is changed to predefined amounts as the concentration of interference ions is maintained constant. The mixtures of these source signals are measured using the Bridge-Type Readout Circuit of Ion-Sensitive Field-Effect Transistor (ISFET). Compared with known sample source signals, the BSS algorithm is confirmed to successfully estimate the original sources from the observed signals of ISFET readout circuit. Afterwards, this work realized the BSS algorithm into a digital hardware system. The computation blocks that execute BSS function are designed based on the floating-point architecture, and are applied using the Xilinx Intellectual Property (IP) modules. Finally, the entire BSS design is embedded into a Field Programmable Gate Array (FPGA). Test results show that the BSS in FPGA effectively generates the original ion signals.

並列關鍵字

Blind Source Separation (BSS) ； Floating Point ； Bridge-Type Readout Circuit ； Ion-Sensitive Field-Effect Transistor (ISFET) ； Field Programmable Gate Array (FPGA)

參考文獻

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