Removal of Pulse Waveform Baseline Drift Using Cubic Spline Interpolation

Baseline drift of pulse waveform caused by breathing and physical movement needs to be removed in pulse wave detection process. This paper presents a removal method of pulse waveform baseline drift using cubic spline interpolation. Methods: Starting points of pulse waveform are selected to be the spline interpolation point. And cubic spline interpolation according to the starting points is used to fit the baseline drift. Subsequently, pulse waveform of baseline drift removed is obtained by pulse wave data minus the corresponding baseline drift values. Results: Pulse waveforms after removing baseline drift are stable and have a minor relative error. Conclusion: The actual measurement results show that the method can inhibit the baseline drift effectively. The method and can be well applied in real-time detection of pulse wave.