Patent ID: 11896351
Assignee: HONG KONG APPLIED SCIENCE AND TECHNOLOGY RESEARCH INSTITUTE CO., LTD
Field: Medical technology (Instruments)
Classification: CPC A  G | IPC A  G

Claim 0:
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.