摘要:
The present disclosure relates generally to patient monitoring systems and, more particularly, to signal analysis for patient monitoring systems. In one embodiment, a method of analyzing a detector signal of a physiological patient sensor includes obtaining the detector signal from the physiological patient sensor, and determining a ratio of the signal between two or more channels. A distribution of the angles between the points of the ratio over time may be used to determine a true ratio or a ratio of ratios for use in the determination of a physiological parameter.
摘要:
Methods and systems are disclosed for producing a plurality of archetype signals in wavelet space at a plurality of wavelet scales. A signal is transformed using a continuous wavelet transform based at least in part on a wavelet function. A scale dependent archetype transformed signal is computed based at least in part on the transformed signal and based at least in part on a natural periodicity of the wavelet function used to transform the signal. Information may be derived about the signal from the archetype transform signal, and stored in memory.
摘要:
A pulse oximetry signal, suitably a photoplethysmogram (PPG), is decomposed by wavelet transform techniques, and the decomposed signal analysed to provide selected physiological data. The signal may be processed to remove noise, artefacts, or transient features. Information on respiration may also be recovered.
摘要:
Systems and methods for detecting and monitoring arrhythmias from a signal are provided. A signal processing system may transform a signal using a wavelet transformation and analyze changes in features of the transformed signal to detect pulse rhythm abnormalities. For example, the system may detect pulse rhythm abnormalities by analyzing energy parameters, morphology changes, and pattern changes in the scalogram of a PPG signal. Further, the system may detect pulse rhythm abnormalities by analyzing both the PPG signal and its corresponding scalogram. Physiological information, such as cardiac arrhythmia, may be derived based on the detected pulse rhythm abnormality.
摘要:
Methods and systems are disclosed for defining a physiological parameter. A first physiological signal is transformed into in a complex transform space, the transformed signal having a magnitude and a phase. The transformed signal is rotated by altering its phase. The rotated signal is inverted, and the inverted signal is aligned in phase with a second physiological signal. The aligned inverted signal and the second physiological signal are combined to form a combined signal indicative of the physiological parameter.
摘要:
Methods and systems are disclosed for tuning first and second wavelet functions to resolve at least one component of a signal. A first characteristic frequency corresponding to a first scale band of interest is determined, and a first wavelet function is tuned to the first characteristic frequency in at least a region of a first scale band of interest. A second characteristic frequency corresponding to a second scale band of interest is determined, and a second wavelet function is tuned to the second characteristic frequency in at least a region of the second scale band of interest. A signal is transformed for the first and second wavelet functions using a continuous wavelet transform to create a transform signal, and a scalogram is generated based at least in part on the transformed signal.
摘要:
Methods and systems are disclosed for computing one or more continuous wavelet transforms on a dedicated integrated circuit. The systems comprise an integrated circuit having a receiver, memory, and processing circuitry. The receiver receives input data corresponding to an input signal. The memory stores information corresponding to one or more wavelet functions scaled over a set of scales. The processing circuitry is configured to compute, in-parallel, various portions of a single continuous wavelet transform of the input signal based on the received input data and the stored information corresponding to a single wavelet function computed over a set of scales.
摘要:
A patient monitoring system may determine portions of a PPG signal that correspond to artifacts, to a baseline shift that exceeds a threshold, or to a pulse-to-pulse variability that exceeds a threshold. The patient monitoring system may identify a contiguous portion of the PPG signal that does not include the determined portions. The contiguous portion of the PPG signal may be used to determine physiological information.
摘要:
Systems and methods for detecting and monitoring arrhythmias from a signal are provided. A signal processing system may transform a signal using a wavelet transformation and analyze changes in features of the transformed signal to detect pulse rhythm abnormalities. For example, the system may detect pulse rhythm abnormalities by analyzing energy parameters, morphology changes, and pattern changes in the scalogram of a PPG signal. Further, the system may detect pulse rhythm abnormalities by analyzing both the PPG signal and its corresponding scalogram. Physiological information, such as cardiac arrhythmia, may be derived based on the detected pulse rhythm abnormality.
摘要:
Methods and systems are disclosed for producing a plurality of archetype signals in wavelet space at a plurality of wavelet scales. A signal is transformed using a continuous wavelet transform based at least in part on a wavelet function. A scale dependent archetype transformed signal is computed based at least in part on the transformed signal and based at least in part on a natural periodicity of the wavelet function used to transform the signal. Information may be derived about the signal from the archetype transform signal, and stored in memory.