摘要
近年来，随着计算机技术的发展，医学信号采集与处理不断向着自动化、智能化的方向发展。许多进口的大型医疗设备，已经具备一定的数据处理功能，但它们一般只是对某一种信号，不能通用，再加之价值昂贵，不能在国内的大多数医疗、实验室和科研单位使用。本课题要研究的内容是构筑一个通用的实验平台，该平台能完成对人体各部位各种神经信息的采集、在线分析任务，同时系统平台具有较强的可扩展性和灵活性。由于神经信息的复杂性和采集信息的困难性，本课题主要完成平台的构架部分，实现软硬件各项基本功能，同时实现脑电、心电信号采集、分析，并从中提取有用的神经信息，应用于麻醉深度分析。在系统扩展阶段主要是强化系统功能，实现对深度神经信息的采集。
在课题的实现中，我们首先对虚拟仪器技术(Virtual Instrumentation，NI)的原理、结构、意义作了详细的介绍和分析。着重分析了虚拟医学信号处理仪器的结构和特点，在此基础上，研究了本系统软硬件的设计和实现方法，其中软件的设计和实现起到了关键的作用。
在具体的实现过程中，按照虚拟仪器技术的构架，我们首先进行了硬件系统的设计和实现，重点是对放大器的设计，从而实现计算机对信号的采集。接着，基于软件在虚拟仪器技术中的重要性，我们从面向对象方法的角度来设计和实现了软件的各项功能。整个软件的功能包括信号实时采集；信号波形显示；信号存储和管理；信号分析处理等。系统采用了NI公司的Measurement studio6.0，利用其提供的控件组进行信号的采集、显示、存储和分析，极大地提高了系统开发效率。最后，在信号分析处理中应用了许多先进的信号分析方法，有效地去除了干扰信号，实现脑电信号和心电信号的分解。
在本文最后，基于系统存在的一些不足，我们提出了一些解决的方法，以期能够为系统的下一步扩展提供帮助，同时我们也展望了虚拟仪器技术在我国医学信号处理领域的发展，希望我国在医学信号处理仪器研制上能健康地发展。
In recent years, along with the development of computer, the medical instruments for acquisition and processing of medical signals are increasingly developing into automatization and intelligentization. Owing to only single signal and very high price, many import medical equipments having ability of data acquisition have not far-ranging been applied by hospital and laboratory. Therefore, the main content of this thesis is set up a universal platform of experiment, which can acqire and real-time analysis the neural information, and have better expansibility and agility. In view of the complexity of the neural information and the difficulty of signals collection, we achieve framework of the system, which consist of software function and hardware function, and actualize collection and processing of EEC and ECG. Moreover, in the extending phase, we strengthen the function of the system, and achieve the deep stratum of neural information.
We introduce and analyse the theory structure and meaning of virtual instrumentation in detail , and emphasize analysis of structure and characteristic of virtual medical signal processing instrument in this paper,. Basing on this, we research the methods of designment and achievement of the system, it is crucial to design and achieve the software function of the system.
In term of the structure of virtual instrumentation, first, we design and achieve the hardware, have emphasis on the signal amplifier for the sake of signal collection in the processing of achieving the thesis. Second, we design and achieve the function of software with object oriented. The software function consist of signal real-time collection, wave display , signal storage and management, signal analysis. With the Measurement studio6.0 of NI and it' s controls, we exploit the system, and enhance the efficiency of exploitation. Finally, many one-up methods of signal processing are applied. It is effective to sieve interferential signals and achieve analysis of EEG and ECG.
In the end of this thesis, we put forward some methods of making up the system limitation to ground the system in the extending phase, and open up prospects for the domain of medical signals processing in china.
引文
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