US 10,376,157 B2
Systems and methods for determining respiration information using phase locked loop
James Dripps, West Linton (GB); James Ochs, Palo Alto, CA (US); and Paul S. Addison, Edinburgh (GB)
Assigned to NELLCOR PURITAN BENNETT IRELAND, Mervue, Galway (IE)
Filed by Nellcor Puritan Bennett Ireland, Mervue, Galway (IE)
Filed on Jan. 21, 2016, as Appl. No. 15/3,761.
Application 15/003,761 is a continuation of application No. 13/343,389, filed on Jan. 4, 2012, granted, now 9,247,896.
Prior Publication US 2016/0135691 A1, May 19, 2016
This patent is subject to a terminal disclaimer.
Int. Cl. A61B 5/0205 (2006.01); A61B 5/08 (2006.01); A61B 5/0295 (2006.01); A61B 5/00 (2006.01); A61B 5/1455 (2006.01)
CPC A61B 5/0205 (2013.01) [A61B 5/0295 (2013.01); A61B 5/08 (2013.01); A61B 5/0816 (2013.01); A61B 5/14551 (2013.01); A61B 5/7225 (2013.01); A61B 5/7246 (2013.01); A61B 5/7278 (2013.01); A61B 5/742 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for determining respiration rate using a patient monitor, the method comprising:
receiving a photoplethysmograph (PPG) signal;
generating, using the patient monitor, an oscillator signal;
generating, using the patient monitor, a phase-shifted oscillator signal based on a phase difference between the PPG signal and the oscillator signal;
generating, using the patient monitor, an amplitude demodulated signal by multiplying the phase-shifted oscillator signal and the PPG signal;
determining, using the patient monitor, the respiration rate based on the amplitude demodulated signal; and
displaying, using a display, the respiration rate.