Patent ID: 9220409
Filing Date: 2015-12-29
Classification: A61B

Abstract:
1. A method of processing a physiological signal to determine a physiological parameter of a subject, the method comprising: receiving, using a pulse oximeter, a light signal attenuated by a subject, wherein the light signal comprises a first component corresponding to a desired component and a second component corresponding to an undesired component; performing, using a pulse oximeter, a first filtering operation on the light signal to remove at least a portion of the undesired component using a first analog filter having a first transfer function to generate a filtered analog signal; converting, using the pulse oximeter, the filtered analog signal into a digital signal; performing, using the pulse oximeter, a second filtering operation on the digital signal using a second digital filter having a second transfer function to generate a filtered digital signal, wherein the second transfer function is substantially an inverse of the first transfer function; and determining, using the pulse oximeter, the physiological parameter based on the filtered digital signal.