Systems and methods for variable filter adjustment by heart rate metric feedback and noise reference sensor

A physiological signal processing system comprising:

• a photoplethysmograph (PPG) sensor that is configured to generate a PPG waveform that includes a cardiovascular signal component and an acceleration signal component therein;
• an accelerometer that is configured to generate an accelerometer waveform including the acceleration component therein;
• a first variable high pass filter that is responsive to the PPG waveform and that is configured to high pass filter the PPG waveform in response to a first corner frequency that is applied thereto;
• a second variable high pass filter that is responsive to the accelerometer waveform and that is configured to high pass filter the accelerometer waveform in response to a second corner frequency that is applied thereto;
• a heart rate metric extractor that is responsive to the first and second variable high pass filters and that is configured to extract a heart rate metric from the PPG waveform that is high pass filtered by the first variable high pass filter and from the accelerometer waveform that is high pass filtered by the second variable high pass filter;
• and
• a corner frequency adjustor that is responsive to the heart rate metric extractor and that is configured to determine the first and second corner frequencies that are applied to the first and second variable high pass filters, respectively, based on the heart rate metric that was extracted.

A physiological signal processing method for a physiological waveform that includes a cardiovascular signal component and a noise component therein, and a noise reference waveform including the noise component therein, the physiological signal processing method comprising:

• high pass filtering the physiological waveform in response to a first adjustable high pass filter corner frequency;
• high pass filtering the noise reference waveform in response to a second adjustable high pass filter corner frequency;
• extracting a heart rate metric from the physiological waveform that is high pass filtered and from the noise reference waveform that is high pass filtered;
• and
• determining the first and second adjustable high pass filter corner frequencies from the heart rate metric that was extracted.