血氧脉搏仪设计 摘要 脉搏血氧仪是一种可连续、无创、方便地检测动脉血氧饱和度的仪器。血氧饱和度的监测目前在急救病房、手术室、监护室、患者的术后恢复、呼吸睡眠的研究以及社区医疗监护等方面得到广泛的应用。同时随着人们对健康关注度的提高，在家庭中也有很大前景。随着微光机电系统技术、生物医学技术及数字信号处理技术的发展，脉搏血氧检测系统正朝着集成化、微型化、数字化方向发展。本设计基于传统的透射式光电采集原理，使用高速集成模拟混合信号芯片C8051F320，设计了双波长血氧脉搏仪。系统采用光源调制、频分测量法和过采样技术，简化模拟电路部分的设计，提高了系统稳定性和重复性。在动态光谱原理基础上，对光电脉搏波信号进行时域频域转换，所得到基波分量用于血氧饱和度计算，获得了高精度的脉搏血氧饱和度测量值。 本文还研究了脉搏血氧仪现况，Lambert-Beer定律在光电采集模型分析与应用，以及光电容积脉搏波描记法、双波长测量法的原理。以及国内外血氧脉搏测量仪的现况。根据脉搏血氧仪的功能和需求，采取便于实时传输的USB通信来进行数据的传输。采集到的结果可以方便的和传送到数据库进行分析对比。便利的采集方式可以增加数据库的容量，为医院、疾病防疫站等机构对疾病的分析统计提供依据。 本设计还包括脉搏血氧仪的软硬件设计及实现。对于硬件先进行原理上的设计仿真，再进行试验样板的制作与验证。软件的设计包括了采集电路信号控制和采集以及USB数据的传输和上位机。最后分析了影响测量精度的各种因素，提出了消除各种干扰信号的处理方法。 关键字：C8051F320、USB、脉搏血氧仪、透射、Lambert-Beer定律 Abstract Pulse oximetry is a co
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n, Lambert-Beer's law 目录 第一章绪论1 1.1引言1 1.2血氧饱合度的测量意义2 1.3血氧饱合度测量的发展状况2 1.4国内外研究现状3 1.5本研究的目的和内容4 1.6本章小结4 第二章无创血氧饱和度脉搏测量的原理和方法5 2.1非侵入式脉搏血氧仪的工作原理5 2.2 Lambert-Beer定律5 2.3光电测量原理7 2.4光电容积脉搏波描记法8 2.5双波长测量法9 第三章硬件电路的设计13 3.1整体电路设计13 3.2电源设计14 3.3双波长发光驱动电路设计15 3.4光电转换电路的设计16 3.5信号分离电路18 3.6带通滤波器设计18 3.7放大电路的设计21 3.8直流偏置电路22 3.9本章小结22 第四章程序设计23 4.1 C8051F320混合信号微控制器介绍24 4.2整体程序设计26 4.3发光管驱动程序设计28 4.4 AD采集程序设计28 4.4.1采用过采样技术提高数据采集精度28 4.4.2 AD采集相关寄存器配置31 4.4.3血氧量的计算31 4.4 USB通信程序设计32 第五章系统分析与实验34 5.1干扰信号产生的原因及处理方法34 5.1.1环境光、暗电流34 5.1.2工频和其它电磁干扰34 5.1.3运动伪差35 5.2实验测量结果35 5.2总结与展望37 谢辞38 参考文献39 附录41 1. C8051F320最小系统原理图： 41 2.信号采集放大电路原理图： 41 3.芯片下载线原理图： 43