DETECTION OF FETAL BREATHING AND CARDIAC MOVEMENTS AND RHYTHMS IN ULTRASONIC DOPPLER SIGNAL RECORDED ON THE SURFACE OF THE MATERNAL ABDOMEN

It is proposed to use information on the direction of reflector moveme nt and extensive filtering in the detection of fetal breathing and car diac movements in the ultrasonic Doppler signal recorded on the surfac e of the material abdomen. The method appears fairly insensitive to sp urious signals and allows those of interest to be distinguished withou t any reference technique. A decision rule for breathing and cardiac r hythm detection, incorporating movement direction, amplitude, shape an d periodicity criteria, is also proposed.