| 摘要 |
<p>Detector signals in a pulse oximeter are analyzed to determine a quality of the signals in relation to physiological information content or artifact content. The analysis involves performing a transform on a signal to obtain frequency related information and analyzing the frequency related information to obtain a value independent of a shape and waveform of a spectrum of the time-based signal. In one implementation, the analysis involves the relative amplitude or power measures of red and infrared spectra. For example, the ratio of the amplitude of the fundamental peak in the red spectrum and the amplitude of the fundamental peak in the infrared spectrum may be tracked over time. In another implementation, the analysis involves consideration of the relative phase of the fundamental and harmonic components of a signal. In either case, signals including desired physiological information can be distinguished from artifact affected signals. Based on this analysis, signals can be validated or an appropriate processing algorithm can be selected.</p> |
