AUTOMATED DIAGNOSIS-ASSISTING MEDICAL DEVICES UTILIZING RATE/FREQUENCY ESTIMATION AND PATTERN LOCALIZATION OF QUASI-PERIODIC SIGNALS

摘要

A method for processing a quasi-periodic signal includes receiving a representation of a quasi-periodic signal and filtering to produce a pre-processed signal. At least a portion of a representation is auto-correlated. A biphasic tapering function including a time constant is applied to the auto-correlation output. A representation, based on the first maximum, is stored in the memory device as an indication of a rate of the quasi-periodic signal. Moreover, a method for localizing a pattern in quasi-periodic signal includes defining a search window based on the estimated rate. A starting position corresponding to a first maximum is defined. A portion of the signal in the search window is cross-correlated with a template signal pattern to produce a second maximum. The second maximum is defined as new starting position and stored. A method for bidirectional communication system includes data transfer between portable devices, electronic stethoscopes and a hospital information system.