Research on multifunctional fitness monitor based on FFT and photoelectric sensor / 中国医疗器械杂志

ABSTRACT

This paper proposes a multifunctional fitness monitor based on FFT and photoelectric sensor, which uses pulse-type and non-invasive detection method to complete the analysis of the human blood oxygen saturation and heart rate. The system collects the absorption of red and infrared light absorbed by fingertip, then by programmable gain amplifier and the Fast Fourier analysis, it extracts the amplitude, frequency of the AC signal. PIC24FJ128GA010 is used to complete the collection, automatic gain judgment and signal processing. Finally, the result is calibrated by pulse blood oxygen emulator. Furthermore, it realizes the pedometer function based on three axles acceleration sensors MMA7260, which enhances fitness monitor's usability and allows people to obtain dynamic physiological signs when exercising.