课程设计报告

摘要：要在LABVIEW环境中进行对声卡编程，就是运用常用周期信号及测试领域特殊信号的双通道模拟输出。由于专用数据采集卡成本比较昂贵、而且和计算机兼容性比较差等缺点，这个论文就是应用性能良好、价格低廉的计算机声卡设计一套基于 LabVIEW 的信号采集分析系统。该系统具有双通道、高保真、22K 甚至 44KHz 的采样率，实现了音频信号的实时采集、实时存储、回放、信号分析（时域分析和频域分析）等多种功能。实验结果表明：该设计方案具有设计简便、成本低、通用性高、扩展性好、界面大方简洁等优点，可广泛应用于工程测量和科学实验室等环境。

关键词：声卡；数据采集；虚拟仪器；LabVIEW ；

1 声卡信号采集系统总体设计方案

声卡采集系统原理框图如下图1所示。它主要由声源、信号调理模块、计算机声卡以及安装于计算机机上的LabVIEW软件等几部分组成。

图1 声卡采集系统原理框图

工作过程为：输入时，测试信号首先经过信号调理电路，利用PC机声卡的麦克风输入（mic in）或线路输入（line in）作为信号的输入端口，将获取到的模拟音频信号经过左右两个通道和A/D转换后送入计算机，通过LabVIEW编写的采集程序进行各种处理和保存；输出时，经过采集系统处理的数据通过总线将数字化的信号以PCM方式送到D/A转换器，编程模拟的音频信号由线路输出（line out）端口通过耳机或音响转换为音波播放出来。

信号调理电路：在信号进入声卡之前必须经过信号调理，主要包括信号的放大、滤波、隔离和线性化处理，以使其能够被声卡正确的识别。声卡的麦克风（mic in）输入端具有高增益放大器，会使得信号产生较大失真，所以选择线路（line in）输入信号时，其输入电压应为-1～+1V。

声卡：计算机的声卡作为数据采集卡，其A/D转换功能已经成熟，而且计算机无需添加额外配件便能完成所有音频信号的采集功能，具有价格低廉、采样精度高，与LabView结合编程简单等优点，因此，利用声卡可以构成一个较高采样精度、中等采样频率、灵活性好的信号采集系统。

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课 程 设 计

Labview 虚拟仪器课程设计

     

 

                          

2013 年  7 月 13 日

合肥工业大学课程设计任务书

虚拟心电图仪的设计

一、虚拟心电图仪设计主要内容

  心电图仪的前面板及框图程序的设计，要求实现心电信号的回放显示、保存、R-R间期及心率等参数的计算。

二、实验设备

  装有Labview的PC一台

三、设计思路

1、心电图仪前面板的设计

  (1) 考虑到设计的心电图仪能够实现对心电信号波形显示，以及回放显示功能，所以设置了两个Wave Graph 面板，一个用于实时显示，一个用于回放显示，如下图示：

实时显示面板：

回放显示面板：

注释：在设计的过程中考虑过将实时显示和回放显示放在一个Wave Graph 中，但是由于这种分开设计的方法更加简单明了，所以最终选择了这种设计.

  (2) 考虑到设计有要求能够显示R-R间期及心率等参数,还要有保存功能键,再结合实际需要,所以,最后的完整面板如下图示:

(因为图太大,所以把整张图截成了两部分)

2、心电图仪框图程序的设计

（1）首先框图程序整体观：

   

   

   

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ENGLISH WRITING EXERCISE SHEET

Zoe Lei

ENGLISH WRITING EXERCISE SHEET

Zoe Lei

ENGLISH WRITING EXERCISE SHEET

Zoe Lei

ENGLISH WRITING EXERCISE SHEET

Zoe Lei

ENGLISH WRITING EXERCISE SHEET

Zoe Lei

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Hamlet

10英教（1） 1028010002 朱莉 Hamlet is a classical representative work of a great English playwright and poet-William Shakespeare. William Shakespeare is often called England's national poet and the "Bard of Avon". His four great comedies are Twelfth Night、Midsummer Night's Dream 、The Merchant of Venice and As You Like It. His four representative tragedies are Hamlet、 Othello、 King Lear and Macbeth. While Hamlet is most popular and the best work in the four representative tragedies, because it is a philosophical exploration of life and death.

The hero of Hamlet is Prince Hamlet of Denmark, son of deceased King Hamlet.When he back the home in a hurry from Germany for his father's funeral ,he only to find his father death mysteriously and his mother remarriage with Claudius- his father’s brother hastily. He is doubt that his uncle killed his mother to rob his beautiful mother and his father throne. Suddenly a Ghost appears to lead Hamlet to a secluded place, claims that it is the actual spirit of his father. It tells hamlet a secret. His father was murdered by his brother Claudius pouring poison in his ear. In order to revenge on his uncle for killing his father, he pretend to be mad and suffered a series of misery. To this, he started the difficult revenge course, launched the life and death contest with Claudius. Finally, sent out sword the revenge to Claudius. Hamlet is a absolute tragedy,

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The Main Difference Between My College Life And My Middle School Life

It is generally accepted by college students that the main difference between middle school and college life lies in the degree of independence. As for me, I prefer the more independent life in university for the following three reasons. First and foremost, since the very day I entered the university, I have learned to live on my own and cultivated the habit of solving problems by myself. Without parents company, I have learned to arrange my daily meals for myself, wash clothes, set financial plans and make decisions relying on myself. Besides, college life is academically different from that in middle schools. Teachers in university only give students due guidance at due time, which renders college students more freedom to set academic goals. What’s more, we can choose any courses we are interested in and the teachers whose teaching styles are to our preference. Last but not least, we enjoy more free extracurricular time. We can make good use of the free time to broaden our views and make more friends.

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The Main Difference between My College Life and My Middle School Life

Before students enter the university, they all want to know the main difference between college life and middle school life. According to my experience, college life has more freedom than the life in middle school. As for me , I prefer the more free life in university for the following three reasons. First, our studying becomes unconstrained. At the middle school, we spend most of our time studying. We have many courses and a lot of work waiting for us to complete. We try our best to study because we all want to go to better universities. But in university, it’s different. We have more time not only for studying but also for many other things. Scores are not the only standard for our life. Besides, we have more freedom in our daily life. In middle school, we always controlled by our parents and teachers. However, we can arrange our time without parents’ company in college life. Last but not least, we enjoy more free extracurricular time. The only thing we can do in middle school is studying. We have no spare time to do what we want to do. But it’s totally different in our college life. We have more free time to take part in various kinds of activities, such as dancing, playing different kinds of balls, which make our life more colorful and meaningful.

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The Main Difference Between My College Life and My Middle

School Life

As we all know, life in college differs from that in the middle school in many aspects. From where I stand, I would say that the main difference between my college life and my middle school life lies in the fact that college provides a more flexible study environment while the latter a rather stereotype style.

Owing to the sharp differences between the two styles, certainly I prefer the college life to the middle school one. There are two major causes resulting in my viewpoint. For one thing, college life makes ampler room for me to study, to entertain myself, and to communicate with other students, which undoubtedly does great good to enhance my knowledge. For another, it is the flexible study model that gives me a great deal of time to touch on other studies, such as arts, history, linguistics and so on, which will help me broaden my horizon and further improve my understanding about society and life.

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