The use of two separate ensemble averagers for processing a detected waveform
for use in calculating oxygen saturation and a pulse rate. The ensemble averager
used for calculating oxygen saturation operates on a signal which has been normalized,
while the ensemble averager for the pulse rate calculation operates on a signal
which has not been normalized. The metrics chosen for the two paths through the
two ensemble averagers can be varied to optimize the ensemble averaging for oxygen
saturation or pulse rate calculations.