摘要脉搏波所呈现出来的形态、强度、速率和节律等方面的综合信息,能反映出人体心血管系统中许多生理疾病的血流特征。根据人体脉搏信号特征,本文设计了一种基于单片机的脉搏测量系统。因为手指放在光的传递路径中,血管中血液饱和度的变化将引起光的传递强度变化,所以,本系统采用了红外发射与接收二极管充当脉搏传感器来采集脉搏信号。首先,将采集到的信号通过低通滤波与放大电路对脉搏信号进行处理,然后,将放大后的脉搏信号通过整形电路进行电压基准变化,再经过一次放大电路对整形后的脉搏信号进行放大,将信号转换为AT89S52单片机易于处理的脉冲信号。通过单片机编程对脉冲信号进行处理,测量出一分钟内的脉搏次数,最终在液晶屏中直观地显示出来。为了节省时间,一般不会作1分钟的测量,通常是测量10秒钟时间内的脉搏数,再把结果乘以6即得到每分钟的脉搏数。当所测得的脉搏次数小于50或大于120时,系统会进行报警。关键词:人体脉搏信号;单片机;信号处理;脉搏传感器;ABSTRACTTheshape,intensity,speed,andrhythmofpulsesignalsreflectthephysicalandpathologicalcharactersofheart-bloodsysteminhumanbodiesmostly.Accordingtothecharacteristicsofthehumanpulsesignals,apulsefluctuationfrequencymeasurementsystemisdesigned.Whenthefingerisputinthedeliverpathoflight,asthesaturationofblooddegreechanges,thestrengthofthelightdeliveredinthepathchanges.Sofirstly,twoinfraredemittingdiodesworkingasapulsesensorarechosentocollectthesignalsofhumanpulse,secondly,anamplificationcircuitandafilterwavecircuittoenlargethesignalareused,thenorthopediccircuitwhichcaninverttheanalogsignalisusedbeforetheamplificationcircuitisusedagainsothatAT89S52singlechipmicrocomputerisabletodealwiththepulsesignalandgetthepulsefluctuationfrequency.Finally,theresultsaredisplayedwithaLCDscreen.Tosavetime,wedonotusuallymeasurethepulseforaminute,wejustmeasureitwithin10seconds,thenmultiplytheresultby6togettheperminute’scountofthepulse.Whenthecountofpulseislessthan50ormorethan120,thebellofthesystemringstogiveawarning.KeyWords:Pulsesignalofhumanbody;singlechipmicrocomputer;treatmentofsignal;pulsesensor;目录1引言..............................................................................................................................12系统概述......................................................................................................................32.1系统总设计目标..................................................................................................32.1.1实现要求...................................................................................................32.1.2主要完成内容...........................................................................................32.2系统总体设计方案..............................................................................................32.2.1系统硬件组成部分...................................................................................32.2.2脉搏传感器的选择...................................................................................42.2.3信号处理电路所用芯片的选择...............................................................52.2.4单片机的选择...........................................................................................53主处理电路的设计......................................................................................................73.1单片机最小系统的设计......................................................................................73.1.1时钟信号...................................................................................................73.1.2RC复位电路.............................................................................................73.2系统模块电路的设计..........................................................................................83.2.1信号采集与信号处理电路的设计...........................................................83.2.2定时电路的设计.....................................................................................103.2.3报警电路的设计.....................................................................................113.2.4显示电路的设计.....................................................................................113.3电路所用芯片简介............................................................................................123.3.1AT89S52芯片简介.................................................................................123.3.2CD4069芯片的简介...............................................................................163.41602液晶屏的简介...........................................................................................173.4.1液晶屏的引脚功能.................................................................................173.4.2液晶屏的显示原理.................................................................................183.5PCB腐蚀板的简介...........................................................................................193.5.1PCB板的简介.........................................................................................193.5.2PCB腐蚀板的制作流程.........................................................................203.6红外发光二极管的简介....................................................................................204系统软件的设计........................................................................................................224.1脉搏频率的测量方法........................................................................................224.1.1周期测量法.............................................................................................224.1.2多周期同步测量法.................................................................................234.1.3频率测量法.............................................................................................23