Abstract: The photoplethysmogram (PPG) is the pulsatile waveform
produced by the pulse oximeter, which is widely used for
monitoring arterial oxygen saturation in patients. Various methods
for extracting the breathing rate from the PPG waveform have been
compared using a consistent data set, and a novel technique using
autoregressive modelling is presented. This novel technique is shown
to outperform the existing techniques, with a mean error in breathing
rate of 0.04 breaths per minute.