Abstract: A method and an apparatus to analyze two measured signals that are modeled as containing desired and undesired portions such as noise, FM and AM modulation. Coefficients relate the two signals according to a model defined in accordance with the present invention. In one embodiment, a transformation is used to evaluate a ratio of the two measured signals in order to find appropriate coefficients. The measured signals are then fed into a signal scrubber which uses the coefficients to remove the unwanted portions. The signal scrubbing is performed in either the time domain or in the frequency domain. The method and apparatus are particularly advantageous to blood oximetry and pulserate measurements. In another embodiment, an estimate of the pulserate is obtained by applying a set of rules to a spectral transform of the scrubbed signal. In another embodiment, an estimate of the pulserate is obtained by transforming the scrubbed signal from a first spectral domain into a second spectral domain.

Abstract: A method of storing streaming physiological information obtained from a medical patient in a multi-patient monitoring environment includes receiving identification information, retrieving parameter descriptors, creating a round-robin database file, receiving a data stream, and using a predetermined data rate to map the data stream to locations in the round-robin database file.

Abstract: An application identification sensor comprises a plurality of emitters configured to transmit light into a tissue site and a detector configured to receive the light after tissue absorption. The detector generates a signal responsive to the intensity of the light and communicates the signal to a monitor. An information element is readable by the monitor so as to identify a sensor application. The monitor presets at least one user-selectable operational parameter in response to the information element.

Abstract: An embodiment of the present disclosure seeks to smooth a perfusion index measurement through use of a baseline perfusion index measurement and/or through the use of multiple PI calculations. The combination of the baseline perfusion index measurement reduces an error between a calculated measurement of PI and actual conditions.