| CPC A61B 5/0205 (2013.01) [A61B 5/1102 (2013.01); A61B 5/113 (2013.01); A61B 5/1126 (2013.01); A61B 5/6892 (2013.01); A61B 5/726 (2013.01); G01L 1/245 (2013.01); G02B 6/4202 (2013.01); G02B 6/4298 (2013.01); A61B 5/02444 (2013.01); A61B 5/0816 (2013.01); A61B 2562/0233 (2013.01)] | 16 Claims |
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1. A fiber-optic sensor comprising:
a fiber-optic cable having an inner core that carries light, a cladding layer around the inner core to reflect light back into the inner core, and an outer coating, wherein a diameter of the inner core is at least 50% of a diameter of the cladding layer around in the inner core;
a symmetric pair of radial ring groups formed by the fiber-optic cable being arranged in a first plane and circled from inside to outside in a first radial ring group in the symmetric pair of radial ring groups, and circled from outside to inside in a secondi radial ring group in the symmetric pair of radial ring groups;
a light source coupled to input an input light into a first end of the fiber-optic cable;
an optical receiver that senses changes in intensity of received light that is received by the optical receiver from a second end of the fiber-optic cable after the input light passes through the symmetric pair of radial ring groups;
a mesh layer having openings formed within the mesh layer, the mesh layer formed in a second plane that is substantially parallel to the first plane;
wherein when pressure is applied by a body, the mesh layer presses upon the fiber-optic cable in the symmetric pair of radial ring groups, wherein a first portion of the fiber-optic cable bends partially into the openings and a second portion of the fiber-optic cable flexes against the mesh layer to vary attenuation of light passing through the fiber-optic cable;
an Analog-of-Digital Converter (ADC) that converts electrical signals from the optical receiver to digital values;
a control and processing unit that processes the digital values from the ADC to generate a respiration rate and a heart rate of the body, wherein the body is moving due to respiration and due to a beating heart within the body;
wherein the control and processing unit performs Daubechies dB5 wavelet decomposition on the digital values;
wherein the control and processing unit performs Daubechies dB5 wavelet decomposition on the digital values to generate intermediate values that include detail coefficients and approximation coefficients;
wherein the control and processing unit performs reconstruction on the detail coefficients to generate a reconstructed dB5 level-4 detail waveform;
wherein the control and processing unit performs reconstruction on the approximation coefficients to generate a reconstructed dB5 level-6 approximation waveform;
wherein the heart rate is extracted from peaks in the reconstructed dB5 level-4 detail waveform;
wherein the respiration rate is extracted from peaks in the reconstructed dB5 level-6 approximation waveform;
wherein the digital values are convoluted with a dB5 scaling function and downsampled to generate a plurality of level-1 approximation coefficients;
wherein the plurality of level-1 approximation coefficients are convoluted with the dB5 scaling function and downsampled to generate a plurality of level-2 approximation coefficients;
wherein the plurality of level-2 approximation coefficients are convoluted with the dB5 scaling function and downsampled to generate a plurality of level-3 approximation coefficients;
wherein the plurality of level-3 approximation coefficients are convoluted with the dB5 scaling function and downsampled to generate a plurality of level-4 approximation coefficients.
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