基于单片机的血压测量计设计.doc

基于单片机的血压测量计设计 Based on monolithic integrated circuits blood pressure survey meter design Abstract:With the improvement of living standard，people more and more concern their health. Blood pressure is an important symbol whether health or not.It is significant to design intelligent sphygmomanometer which applied to both family member and doctor.In this paper, the ambulatory blood pressure detection of computer-detection and control of the area, because in the various sectors of the national economy has infiltrated computer detection and control system. National defense technology, aerospace, aviation, railways, metallurgy, chemical industry naturally Needless to say, even in daily life also use the computer monitoring and control technologies, such as elevators, microwave ovens, refrigerators and so on. Therefore, it will own after the study in mechatronics product development is of great significance. A blood presser dynamic testing system will be worked out in this article, which use testing technique of delicated signal.The sphygmomanometer can be used simple blood pressure measure.This article use PIC singlechip “PIC16F874” as the sphygmomanometer’s kernel,which is prevalent at present.Pressure which blood oppress vein is translated to electric signal.Through PIC16F874‘s A/D translation model it is be transformed digital signal.Then the singlechip processes these digital signal such as display, saving, transmitting. Keywords:Blood pressure；singlechip；sensor；LED 第1章 绪 论 1.1 课题研究的意义和总体目标 1.1.1 课题研究的意义  第2章 设计的总体思路和基本方法 图2-1 硬件图 图2-2 硬件工作流程图 2.2 微弱信号的检测方法 提高信号检测灵敏度或降低可检测下限的基本方法有两类。一是传感器及放大器入手，从降低它们的固有噪声水平，或研制新的低噪声传感器。另一是分析测员中的噪声规律和信号规律，通过各种手段从噪声中提取信号。微弱信号检测是利用后一种途径。但应注意，从噪声中提取信息，首先需在尽量降低噪声的基础上进行。微弱信号的检测方法随信号类型不同而不同，目前常用的和比较成功的方法有以下几种。 (1)、信号的窄带化及相干检测技术 单频余弦(或正弦)信号，或频带很窄的正、余弦信号，由于信号频率固定，我们以通过限制测量系统带宽的方法，把大量带宽外的噪声排除。这种技术称为窄化技术。如果信号具有相干性，而噪声具有无相干性，则可利用相干检测技术，把相位不同于信号的噪声部分排除，即可把与信号频率相同，但相位不同的噪声大量排除。 20世纪50年代后发展的锁相放大器，是以相敏检波(PSD)为基础的，是目前电频域信号相干检测的王要仪器。其基本原理是利用PSD既