基于STM32的数字血氧饱和度检测系统设计

摘要

目的:血氧饱和度指血液中氧合血红蛋白占总血红蛋白的比例,直接反映人体的氧代谢状况,是医学监护的重要指标.本文以嵌入式ARM系统为核心,设计出一个低功耗、低成本和高精度的血氧饱和度检测系统.它充分利用嵌入式处理器丰富的片上外设的优势,对血氧饱和度参数进行采集、分析和显示处理,整体设计方案可为家庭监护产品设计提供依据.方法:本文以STM32F103C8T6芯片作为核心处理器,采用IAR EWARM的软件开发平台,实现血氧饱和度系统的设计.硬件设计方面,采用芯片的内部时钟进行光电信号的驱动,并用其内部定时器实现信号的采样.信号处理方面,设计出自适应的参数训练算法,提高血氧值计算的有效性.结果:系统可实现信号采集、信号处理、实时显示、报警、数据存储、自动断电、实时时钟等功能.数字化血氧探头的设计,可有效减少模拟电路处理,降低电路噪声的影响.结论:实现了数字血氧饱和度检测设备的软硬件设计,通过模拟设备检测证明,该系统具有精确度高、重复性好等优点,实用性强.%Blood oxygen saturation is the percentage of oxygenated hemoglobin versus total hemoglobin in blood. This index directly reflects the condition of human metabolism, and is an important factor for medical monitor. With embedded system as core component, a blood oxygen saturation detection system is designed, which is with low power consumption and cost while with high precision. By fully utilizing the advantages of peripherals in embedded system, this system can do blood oxygen saturation processing, including sampling, analysis and display. The whole solution can be a sample to further build up family nursing devices. Methods: Using the processor of STM32F103C8T6 and running on IAR EWARM platform, the blood oxygen saturation detection system is designed. Hardware wise, embedded clock is used to drive photoelectric signal, and inter nal timer is used to do the signal sampling. Regarding digital signal processing, a new self adaptive and parameterized training algorithm is proposed, which largely improves the effectiveness of various calculation for blood oxygen saturation. Results: This system supports functions of signal acquisition, signal processing, real-time display, alarming, data storing, auto power off, real-time clock and etc. The component of digital probe for blood oxygen, can largely reduce corresponding analog processing, which minimize the impact from circuit noise. Conclusions: The prototype of digital blood oxygen saturation detection system is raised, and corresponding hardware and software are designed. Through simulation, this system is proven highly precise, re-peatable and quite practical.