An ear-worn device includes a speaker, an optical emitter, an optical detector, a processor, and a housing configured to be positioned within an ear of a subject, wherein the housing encloses the speaker, optical emitter, optical detector, and processor. The housing includes at least one window that exposes the optical emitter and optical detector to the ear of the subject, and the housing includes at least one aperture through which sound from the speaker can pass. Light transmissive material is located between the optical emitter and the at least one window and is configured to deliver light emitted from the optical emitter to an ear region of the subject at one or more predetermined locations. Light transmissive material is positioned between the optical detector and the at least one window and is configured to collect light external to the housing and deliver the collected light to the optical detector.

A device may be configured for performing signal processing in impedance sensing applications, and more specifically, for recovering data from an amplitude-modulated signal. In one aspect, a device includes a sensing circuit operable to sense an amplitude-modulated signal having a carrier frequency. The device also includes a mixer operable to mix the amplitude-modulated signal with a mixing signal having a mixing frequency to provide a frequency-downshifted signal having an intermediate frequency less than the carrier frequency. The device also includes a filter operable to filter the frequency-downshifted signal to provide a filtered signal. The device further includes a sampler operable to undersample the filtered signal at an undersampling frequency to provide a digital signal, the digital signal being representative of a modulating signal.

A system for collecting data for assessment of cardiovascular function includes a plurality of monitoring devices coupled to different respective body parts. Each monitoring device is configured to measure a respective signal at the respective body part in response to cardiovascular activity. The respective signal includes a cardiovascular component attributable to the cardiovascular activity and an artifact component not attributable to the cardiovascular activity. When the monitoring devices measure the respective signals simultaneously over a same time period, the cardiovascular components are correlated, and the artifact components are not correlated. The system also includes a controller configured to: identify the cardiovascular components included in the signal measurements, according to the correlation of the cardiovascular components; reject the artifact components included in the signal measurements, according to the non-correlation of the artifact components; and determine cardiovascular information from the identified cardiovascular components for an assessment of cardiovascular function.

A system for collecting data for assessment of cardiovascular function includes a plurality of monitoring devices coupled to different respective body parts. Each monitoring device is configured to measure a respective signal at the respective body part in response to cardiovascular activity. The respective signal includes a cardiovascular component attributable to the cardiovascular activity and an artifact component not attributable to the cardiovascular activity. When the monitoring devices measure the respective signals simultaneously over a same time period, the cardiovascular components are correlated, and the artifact components are not correlated. The system also includes a controller configured to: identify the cardiovascular components included in the signal measurements, according to the correlation of the cardiovascular components; reject the artifact components included in the signal measurements, according to the non-correlation of the artifact components; and determine cardiovascular information from the identified cardiovascular components for an assessment of cardiovascular function.

A method includes transmitting electrical signals between one or more pairs of body-surface electrodes attached to a body of a patient. Electrical potentials resulting from the transmitted electrical signals are acquired by an outer-facing electrode and an inner-facing electrode of a medical probe inserted in an organ of the patient. A proximity of the medical probe to surface tissue of the organ is estimated based on the electrical potentials acquired by the outer-facing electrode. A position of the medical probe within the organ is estimated based on the electrical potentials acquired by the inner-facing electrode.

A method includes transmitting electrical signals between one or more pairs of body-surface electrodes attached to a body of a patient. Electrical potentials resulting from the transmitted electrical signals are acquired by an outer-facing electrode and an inner-facing electrode of a medical probe inserted in an organ of the patient. A proximity of the medical probe to surface tissue of the organ is estimated based on the electrical potentials acquired by the outer-facing electrode. A position of the medical probe within the organ is estimated based on the electrical potentials acquired by the inner-facing electrode.

Provided according to embodiments of the invention are methods of monitoring the direction of blood flow that include processing with a computer photoplethysmography (PPG) signal streams from a sensor array on a body site of the individual to determine the direction and/or velocity of the blood flow at the body site of the individual. In some embodiments, direction of the blood flow at the body site is determined by the phase difference between at least three PPG signal streams from the sensor array, wherein the at least three PPG signal streams are generated from emissions of the at least three emitters.

Provided according to embodiments of the invention are methods of monitoring the direction of blood flow that include processing with a computer photoplethysmography (PPG) signal streams from a sensor array on a body site of the individual to determine the direction and/or velocity of the blood flow at the body site of the individual. In some embodiments, direction of the blood flow at the body site is determined by the phase difference between at least three PPG signal streams from the sensor array, wherein the at least three PPG signal streams are generated from emissions of the at least three emitters.

A wearable device includes a housing with a window and an electronic module supported by the housing. The electronic module includes a photoplethysmography sensor, a motion sensor, and a signal processor that processes signals from the motion sensor and signals from the photoplethysmography sensor. The signal processor is configured to remove frequency bands from the photoplethysmography sensor signals that are outside of a range of interest using a band-pass filter to produce pre-conditioned signals, and to further process the pre-conditioned signals using the motion sensor signals to reduce motion artifacts from footsteps during subject running. The device includes non-air light transmissive material in optical communication with the photoplethysmography sensor and the window that serves as a light guide for the photoplethysmography sensor. The window optically exposes the photoplethysmography sensor to a body of a subject wearing the device via the non-air light transmissive material.

An identification device including a generation unit and an information identification unit. The generation unit generates factor information relating to pulse-wave information with respect to an identification target in accordance with biological model information representing a relevance between pulse-wave information representing a pulse wave and the factor information representing a factor of pulse wave. The information identification unit selects certain list information satisfying a predetermined determination criterion of the factor information generated by the generation unit out of list information associating the factor information generated based on the pulse-wave information representing a pulse wave of a biological subject to be an identification target with identification information for identifying the biological subject, and identifies the identification information in the selected certain list information.