标题: | 锁相回路应用于脑电波之瞬间频率侦测 Detection of instantaneous frequency in EEG using phase locked loop |
作者: | 李豫勇 Lee, Yu-Yun 罗佩祯 Pei-Chen Lo 电控工程研究所 |
关键字: | 锁相回路;脑电波;phase locked loop;EEG |
公开日期: | 1995 |
摘要: | 在这篇论文中,我们讨论锁相回路的基本理论和一些特性,脑电波的频 率侦测以及锁相回路的硬体实作。我们利用锁相回路电路做为侦测脑电波 频率的工具。锁相回路被广泛的使用于通讯领域中。一般而言,锁相回路 在处理单一高频讯号时,成效相当好。然而脑波讯号是低频而且有多个频 率组成的讯号。为了开发能即时侦测脑波瞬间频率的系统,我们首先藉由 电脑模拟来观察锁相回路的特性。在此研究过程中,我们将探讨它在低频 和高频环境的特性及工作情形。藉由此观察,我们对锁相回路的结构稍做 修正,其修正后的系统将得以侦测到脑波的频率。 为了进一步去验证模 拟的结果,我们将 PLL的硬体系统设计并制作出来,用来处理模拟的低频 讯号,得到的结果和电脑模拟是非常相近的。从这个初期研究工作□,锁 相回路是可以用于侦测脑波频率的。 In this thesis, we discuss the fundamental theory and characteristicof phase locked loop ( PLL ), detection of the frequency of EEG signals,and hardware implementation of PLL circuits. We apply PLL to detectionof the frequency of EEG signals. PLL has been widely used in communicationsystems. In general, PLL performs well for high-frequency, pure sinusoidalsignals. However, EEG is a low-frequency and multi- component signal. In consideration of developing a real-time instantaneous frequency detection for EEG analysis, we begin with investigation of fundamental propertiesof PLL through computer simulatiion. The performance of PLL under both low- frequency and high-frequency situation is analyzed. It is found a modification of the PLL enables detection of time-varying frequency ofEEG. To further verify results of simulation, a hardware-realized system isdesigned and implemented to simulated low-frequency signals. Results of frequency detection by the hardware PLL system agree with which of computersimulation. From this preliminary research work, PLL is feasible for real- timedetection of EEG's frequency. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#NT840327025 http://hdl.handle.net/11536/60281 |
显示于类别: | Thesis |