Lung sound crackle analysis using generalised time-frequency representations

The fetal heart rate showed normal accelerations after periods of increased fetal motor activity. The presence of decelerations after uterine contractions was also observed, the latter being announced by the subject. The percentage of correct detection of the fetal heart rate exceeded 90 per cent. The breathing movements, frequently observed on the echographic screen, were rarely seen in the processing results. The reason for this was most probably the design of the transducers, which is currently being modified. Strong maternal movements producing signals in the band of the system inevitably disturb its functioning. To avoid considering these as fetal movements, the envisaged solution is to detect them using another sensor (e.g. an acceleration transducer). The presented system has the potential to provide extended information on fetal activity. Obviously, it needs further validation and development. In particular, it is envisaged to implement a further reduction of the information retained.