This relates to systems and methods for determining one or more of a user's physiological signals. The one or more of the user's physiological signals can be determined by measuring pulsatile blood volume changes. Motion artifacts included in the signals can be canceled or reduced by measuring non-pulsatile blood volume changes and adjusting the signal to account for the non-pulsatile blood information. Non-pulsatile blood volume changes can be measured using at least one set of light emitter-light sensor. The light emitter can be located in close proximity (e.g., less than or equal to 1 mm away) to the light sensor, thereby limiting light emitted by the light emitter to blood volume without interacting with one or more blood vessels and/or arterioles. In some examples, the systems can further include an accelerometer configured to measure the user's acceleration, and the acceleration signal can be additionally be used for compensating for motion artifacts.

One aspect of the present disclosure relates to a system that can prevent unintended signal components (noise) in an electric waveform that can be used for at least one of neural stimulation, block, and/or sensing. The system can include a signal generator to generate a waveform that includes an intended electric waveform and unintended noise. The system can also include a signal transformer device (e.g., a very long wire) comprising a first coil and a second coil. The first coil can be coupled to the signal generator to receive the waveform and remove the unintended noise from the electric waveform. The second coil can pass the electric waveform to an electrode. The second coil can be coupled to a capacitor that can prevent the waveform from developing noise at an electrode/electrolyte interface between an electrode and a nerve.

A pulse wave sensor includes: a white LED emitting white light to a human body; a G sensor converting, into a first electrical signal, green light included in light emitted from the white LED and reflected within the human body; an R sensor converting, into a second electrical signal, red light included in the light emitted from the white LED and reflected within the human body; and an arithmetic control unit configured to generate a signal showing a heart rate based on a level difference between the first electrical signal and the second electrical signal. Therefore, a distance between the G sensor and the R sensor does not have to be increased, so that an apparatus can be reduced in size.

The present invention relates to a device, system and a method for generating a photoplethysmographic image carrying vital sign information of a subject. To provide an increased validity and robustness against motion, in particular against ballistocardiographic motion, the proposed device comprises an input interface (30) for obtaining image data of a skin region of a subject in at least two different wavelength channels, said image data comprising two or more image frames acquired by detecting light transmitted through or reflected from the skin region over time, wherein said image data comprise wavelength-dependent reflection or transmission information in said at least two different wavelength channels, a combination unit (31) for combining, per pixel or group of pixels and per time instant, image data values of said at least two different wavelength channels to obtain a time-variant pulse signal per pixel or group of pixels, and an image generation unit (32) for generating a photoplethysmographic image from a property of the respective pulse signals in a time window including at least two image frames.

A method and an apparatus for separating a composite signal into a plurality of signals is described. A signal processor receives a composite signal and separates a composite signal in to separate output signals. Pre-demodulation signal values are used to adjust the demodulation scheme.

A heart monitoring system for a person includes one or more wireless nodes; and wearable appliance in communication with the one or more wireless nodes, the appliance monitoring vital signs.

A chewing detecting device includes: earphone-type external auditory meatus sensors which have a pair of a light emitting element and a light receiving element and in which the light receiving element receives reflective light of light emitted by the light emitting element into an external auditory meatus to output a voltage signal corresponding to a light receiving amount; association processing means associating an output signal of the external auditory meatus sensors with a motion of a jaw, and outputting a chewing signal showing that the jaw performs chewing; and chewing section sensing means which determines whether or not an output of the external auditory meatus sensors is based on the motion of the jaw (within a chewing section), and which invalidates the output of the association processing means when the output of the external auditory meatus sensors is not based on the motion of the jaw (without the chewing section).

A multiparameter monitor (MPM) for a patient includes a disposable electrode patch (DEP) comprising a plurality of male snap post electrodes, an optics interface and a thermal/respiratory interface to a skin surface of the patient. The MPM also includes an electronics module and wireless transmitter (EMT) in connection with a plurality of female snap receptors and configured to transmit a signal data based on a connection and a disconnection of the plurality of the female snap receptors to the male snap post electrodes. The MPM additionally includes a reflective pulse oximeter (RPO) separated from a skin surface of the patient based on a thickness of the DEP, the RPO in communication with the wireless transmitter. The MPM further includes a mobile photoplethysmogram processor (PPG) in communication with the wireless transmitter and the optics interface and configured to filter a motion artifact in the PPG.

Various embodiments provide a computer device for attenuating motion artifacts in photoplethysmography (PPG) in real time and a method using the same. The computer device obtains a primarily restored PPG AC signal from a distorted PPG signal by using an exponentially weighted moving average filter and restores the final PPG AC signal from the primarily restored PPG AC signal through block interleaving. The computer device includes an initial unit obtaining a basic period of a PPG signal from a PPG sensor in an initial state, an update unit obtaining a waveform and period of a PPG signal not having distortion from the PPG sensor in the state in which motion artifacts are not present, a compensation unit detecting the final PPG AC signal by restoring a waveform of the distorted PPG signal, and a command unit outputting the final PPG AC signal.

Provided is a method for compensating for tissue motion during magnetic resonance (MR) imaging, and an apparatus for use thereof. The method includes acquiring a plurality of short-time MR scan images; selecting a reference scan image from the acquired plurality of short-time MR scan images; defining a set of transformation images based on the acquired plurality of short-time MR scan images other than the selected reference scan image; registering the reference scan image and the defined set of transformation images; calculating an average of aligned, registered images of the defined set of transformation images; and generating a motion-corrected image based on the calculated average.