臺灣博碩士論文加值系統

現今量測的技術上，在現場量測的訊號多為暫態時變訊號且夾雜許多高頻雜訊，而整個系統如何達到即時監控並能提高訊號雜訊比，擷取有效訊號是相當重要的課題。
本文採用小波理論來分析暫態訊號，因為小波函數具有局部性與多層次解析能力的特性，能將有效訊號與雜訊作有效的隔離。並且小波演算法的架構適合應用於即時的運算，且能作彈性化的設計。
所以本文以小波演算法為核心程式，配合數位訊號處理專用晶片TMS320C32，建立一套能即時監視的訊號量測系統。起初以SIMULINK軟體建構小波演算模型，但在本系統其取樣頻率無法提昇，原因是模型的規模過大，為了縮小程式的規模因此改用C++直接編寫程式碼。而在系統實驗中實際輸入一些較單純的暫態突變訊號，進而探討其結果。

Signal detection is an important topic to increase signal to noise ratio and to execute the real-time monitoring. In present study, the wavelets theory is used to analyze the transient signal. The character of localization and the multiresolution capability of the wavelets theory can separate the signal and noise effectively. Thus it is suitable for the real-time analysis.
In this work, a real-time measuring system that use SIMULINK® and C++ software to build the wavelet model based on the TMS320C32 Board is established.
Some simple transient signals have been put in the system to test its efficiency. The result of C++ software is better than that of SIMULINK® . However, it still needs improvements to used in real situations.

頁數
中文摘要 Ⅰ
英文摘要 Ⅱ
目錄 Ⅲ
圖目錄 Ⅴ
第一章 緒論 1
1.1 研究動機與目的 1
1.2 相關研究 2
第二章 小波理論之簡介 4
2.1 箱型函數與多層解析空間 4
2.1.1 階梯函數與箱型函數 4
2.1.2 多層解析空間 5
2.1.3 正則基底 7
2.2 哈耳函數(Haar function) 7
2.3 多層解析空間的基底變換 9
2.4 自格函數(Scaling function) 11
第三章 離散小波轉換與訊號處理 19
3.1 離散小波轉換 20
3.2 小波轉換之矩陣運算 22
3.3 縮減法(Thresholding ) 24
3.4 小波轉換與傅立葉轉換之比較 25
第四章 即時系統發展與模型建立 29
4.1 系統硬體 29
4.1.1 硬體 29
4.1.2 軟體 30
4.2 Model-To-Chip 之系統流程 31
4.3 產生目的碼----使用Pipe-Line觀念 32
第五章 結果與討論 33
第六章 結論與展望 36
參考文獻 38

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