Patent ID: 8886465

Claim:
A method of adjusting sensing in a medical device, comprising: determining light emitted by a plurality of light sources at a plurality of wavelengths received at a detector; determining a plurality of light measurements in response to the emitted light detected by the detector; updating, for each of the plurality of wavelengths, a first normalization coefficient and a second normalization coefficient in response to the detected emitted light, wherein the first normalization coefficient corresponds to peak-to-peak changes in the plurality of light measurements and the second normalization coefficient corresponds to average amplitudes of the plurality of light measurements; and adjusting the determined plurality of light measurements in response to the first normalization coefficient and the second normalization coefficient, the method further comprising: determining a first baseline associated with the first normalization coefficient and a second baseline associated with the second normalization coefficient; updating the first normalization coefficient by calculating a ratio of the first baseline and an average of the peak-to-peak changes in the plurality of light measurements; and updating the second normalization coefficient by calculating a difference between a second baseline and a product of the previously updated first normalization coefficient and a current average amplitude.