【作者】 李长旺；

【导师】 吴小培；

【作者基本信息】 安徽大学 ， 计算机应用技术， 2007， 硕士

【摘要】 心脏病已成为危害人类健康的主要疾病之一。据统计，心血管疾病是威胁人类生命的主要疾病，世界上心脏病的死亡率仍占首位。因此，对心血管疾病的诊断、治疗一直被世界各国医学界所重视，准确地进行心电信号提取，为医生提供有效的辅助分析手段是重要而有意义的课题。随着电子技术的迅速发展，医用电子监护系统近年来己在临床诊断中逐渐应用。本课题首先介绍了心电信号检测电路的设计，给出了心电信号采集电路具体的设计方法与部分实现电路。并采用了线性光电耦合器放大电路，对前置级运算放大电路及后置级放大电路进行光电隔离，有效地抑制了各种干扰。其次，主要进行基于AT89C52低功耗MCU的便携式心电监护仪及其系统的研究。根据人体心电信号的特征，设计性能优良的心电信号采集系统，选用低功耗8位单片机AT89C52和大容量Flash存储器对采集的心电信号进行记录、分析及处理。所设计的监护系统带有液晶显示器，能显示所检测的心电信号，配合按键提供友好的中文菜单，操作简便，心电数据也可通过RS-232接口向上位机传送。该监护仪器能长期、连续、可靠、稳定的工作；同时还具有体积小、存储容量大、功耗低等特点，便于随身携带，使用方便。再次，由于越来越多的研究者发现心电图中的ST段的变化与大多数心血管疾病都有着紧密的联系，因此，本课题设计了心电信号预处理方法，包括4点平均滤波、滑动平均滤波、一阶差分、二阶差分等；在此基础上，设计了基于二阶差分可变阈值检测方法来检测心电波形中的R波，计算出了较为准确的心率值。设计了心电波形特征点定位算法，对波形的特征点进行了标定，并测定ST段电平偏移，从而实现了ST段的实时分析。另外，运用自适应相干模板法的基本原理，实现了ECG信号中噪声和干扰的实时滤波，达到了预期的效果。最后，作者指出本系统存在的一些不足以及能够改进的地方，并对心电处理系统提出展望。更多还原

【Abstract】 Heart disease has become one of the main diseases that harm the health of human beings. On statistics, cardiovascular disease is the major illness threatening human’s life and the death rate of heart disease is still the highest in the world. Thus, the medicine circles all over the world always attach importance to diagnose and cure cardiovascular disease. It is an important and meaningful task to extract ECG precisely and provide auxiliary analytical measures for doctors. With the rapid development of electronic technology, medical electronic monitoring system gradually applied in the clinical diagnosis in recent years.Firstly, this thesis introduces the ECG detection circuit and gives ECG acquisition circuit, especially the specific design and some circuits. It adopts the linear photo-electricity coupling amplifier to segregate prepositional operation amplifier circuit from postpositional one, which depresses various kinds of interference effectively.Secondly, the research is mainly about AT89C52 Low Power MCU-based portable ECG monitor and its system. According to the ECG human characteristics, we design excellent ECG data acquisition system and select low-power 8-bit MCU AT89C52 and large-capacity flash memory of the ECG signal to record, analyze and process the ECG data. The monitoring system with LCD display can show ECG waveform. The keyboard is provided with the friendly Chinese menu, simple and convenient, and ECG data can be transmitted through the RS-232 interface to host computer. The monitoring equipment can do their work continuously, reliably and stably in the long term. In addition, it has other advantages, e.g. small in size, large storage capacity, low power consumption, easy to carry and use.Thirdly, more and more researchers find that the majority of cardiovascular diseases have close relationship to ECG ST segment changes. So this passage studies preprocessing methods: 4-point moving average filter, first order differential and second order differential. Bsaed on the second-order differential variable threshold detection method, the R wave of ECG waveform, a more accurate calculation of the value of HR can be detected. Designing characteristics of the ECG waveform on locating points, calibration points and determination of ST level migration, thus the real-time analysis of the ST segment can be realized. In addition, the use on the basic principles of adaptive coherent template of a real-time ECG signal interference and noise filtering achieves the desired results.Finally, the author points out some shortcomings about the system and gives more prospects to cardiac systems.更多还原