摘要
心率是人體中一個非常重要的生命信息,而傳統的脈診由于其定性化和主觀性影響了心率測試的精度,成為中醫脈診應用、發展和交流中的制約因素。為了提高對此類生物醫學信號的測試精度,必須結合現代科學技術。
介紹一種以AT89S52為控制核心的智能人體心率檢測裝置的設計方法。利用光電傳感器采集人體脈搏信號,經過前置級放大、濾波、積分比較等信號處理電路,將其轉換成脈沖電壓信號,再利用單片機對脈沖信號進行處理計算出心率并顯示。由于傳感器信號十分微弱,其幅度一般在微伏到毫伏的數量級范圍,且夾雜著各種噪聲和干擾,因此要求前置級放大電路具有高增益、高共模抑制比等技術指標。實現了微小信號放大、顯示及報警功能。具有測量靈敏度高、實時性好、性價比高等優點。
本課題硬件設計用Protel99 SE工具，軟件仿真用Keil c V3.60語言編程。系統經調試，功能穩定，均實現各項任務指標。
關鍵詞：心率；濾波器；放大器；脈沖計數
ABSTRACT
Human heart-rate is a very important life information. But the traditional pulse diagnosis affected the accuracy of heart-rate testing because of its qualitative and subjective, which had some constraints as application of pulse diagnosis, development and communication. To improve the signal for such biomedical testing accuracy, modern heart-rate detecting must be combined with modern science and technology.
The design method of intelligent heart-rate measuring instrument was based on AT89S52. The pulse signal was collected by photoelectric-sensor, then converted into pulse voltage signal through the signal processing circuits of pre-amplifying, LPF, integral comparator. Finally, the pulse voltage signal was inputted the single chip microcomputer which calculated heart-rate and displayed the result. The sensor signal was so weakly that its amplitude was in the range of micro-voltage to MV, and including all kinds of noise and interference. Therefore the pre-amplifier must be high gain, high common-mode rejection ratio, and other technical parameters. Experimental result s showed that the system scheme and hardware & software were rational, carried out required functions.
The hardware of this topic was designed by Protel99 SE, the hardware emulator was designed by base Keil c V3.60.When the system was debugged, it carried out all required precision.
