Signal processing apparatus and method

In a physiological monitor attached to a living organism, said organism having a heart beating at an unknown pulserate, said monitor having a detector responsive to physiological properties relating to heartbeats, said detector producing a detector output waveform, a method comprising the steps of:

• transforming said detector output waveform into a spectral domain waveform;
• identifying a series of spectral peaks and peak frequencies corresponding to said spectral peaks in said spectral domain waveform;
• and
• applying a plurality of rules to said spectral peaks and said peak frequencies in order to determine an estimate for said pulserate.

A physiological monitor adapted to be attached to a living organism, said organism having a heart beating at an unknown pulserate, said monitor comprising:

• a detector responsive to physiological properties relating to said heartbeats, said detector producing a detector output waveform;
• and
• a signal processor operatively coupled to said detector, said signal processor receiving said detector output waveform, said signal processor configured to:
• perform a first transform to transform said detector output waveform into a waveform in a first transform domain;
• perform a second transform, to transform said waveform in said first transform domain into a waveform in a second transform domain;
• search said waveform in said second transform domain for a largest spectral peak and a first frequency corresponding to said largest spectral peak;
• and
• compute an estimate of said unknown pulserate from said first frequency.

In a physiological monitor attached to a living organism, said organism having a heart beating at an unknown pulserate, said monitor having a detector responsive to physiological properties relating to said heartbeats, said detector producing a detector output waveform, a method comprising the steps of:

• performing a first transform to transform said detector output waveform into a waveform in a first transform domain;
• performing a second transform, to transform said waveform in said first transform domain into a waveform in a second transform domain;
• searching said waveform in said second transform domain for a largest spectral peak and a first frequency corresponding to said largest spectral peak;
• and
• computing an estimate of said unknown pulserate from said first frequency.