Abstract: Systems and methods for interference and motion detection from dark periods are provided, including analysis of a physiological signal to determine a physiological parameter of a subject, using a photoplethysmography system to monitor signals during an LED-off period to identify interference or motion artifacts in the signal.

Abstract: Systems and methods for interference and motion detection from dark periods are provided, including analysis of a physiological signal to determine a physiological parameter of a subject, using a photoplethysmography system to monitor signals during an LED-off period to identify interference or motion artifacts in the signal.

Abstract: Systems and methods for providing power to a light source of a physiological system and for generating a desired signal. The physiological system may comprise a light drive circuit that may provide a digital signal to the light source of the physiological system. The digital signal may comprise a plurality of pulses. The plurality of pulses may include one or more features that may be adjustable to vary the power provided to the light source. For example, the pulses may have a varying width. The light drive circuit may be configured to provide power to the light source during each pulse of the plurality of pulses. The system may further comprise a front end circuit configured to receive the light generated by the light source in response to the plurality of pulses, where the light is attenuated by a body tissue of a patient. The front end circuit may comprise a response time.

Abstract: Various methods and systems for the use of capacitance sensors within medical devices configured for patient monitoring are provided. The capacitance sensors are configured to measure a change in capacitance resulting from a material (e.g., human tissue, water, gel, cloth, etc.) placed near (e.g., close proximity to) the medical device and/or resulting from a material making physical contact with the medical device. In certain embodiments, the capacitance sensor may be utilized to detect whether one or more portions of the medical sensor are securely applied to the patient's tissue (e.g., sensor “on”) and/or may be utilized to detect whether one or more portions of the medical sensor fail to maintain secure contact with the patient's tissue (e.g., sensor “off”). Further, in certain embodiments, the capacitance sensor may be utilized to distinguish between one or more types of materials (e.g., human tissue, water-based materials, etc.).

Abstract: A physiological monitoring system may receive a sensor signal from a physiological sensor. The system may generate an estimate of the sensor signal based on, for example, prior received signals. The estimate signal may be subtracted from the sensor signal using a transimpedance amplifier to generate a difference signal. A gain and/or offset may be applied to the difference signal by the amplifier. The amplified difference signal may be digitized and combined with the estimate signal to generate a high resolution digital representation of the sensor signal. Physiological information such as blood oxygen saturation, pulse rate, respiration rate, respiration effort, blood pressure, hemoglobin concentration, any other suitable physiological parameters, or any combination thereof, may be determined using the digitized sensor signal.

Abstract: A physiological monitoring system may use a differential light drive to illuminate one or more light sources. A differential light drive may include applying two signals, one to each terminal of a light emitting diode or other light source, such that the illumination of the light source is controlled by the difference between the two light drive signals. In some embodiments, light emitting diodes may be turned on and off using a differential light drive without using switches and using only unipolar voltage sources. In some embodiments, light drive signals may be 180 degrees out-of-phase, and the phase shift may be used to reduce crosstalk and other electronic noise, for example by carrying the signals in a twisted pair of conductors.

Abstract: The present invention is directed to a High Frequency (HF) shunt antenna which promotes improved performance over currently available antenna solutions. The HF shunt antenna may include a shunt plate structure which includes multiple shunt plates configured in a parallel orientation relative to each other and provides an expansive surface area which may promote reduced inductance and lower equivalent parallel resistance of the HF shunt antenna, thereby allowing the HF shunt antenna to be spec-compliant and tunable by a HF coupler, without increasing the footprint of the HF shunt antenna and without reducing radiation efficiency of the antenna.