Blind signal separation with undersampled signals for frequency modulated echoes

Ultrasound technology in medical examinations has developed further in recent years. Above all, the system monitoring the fetal well-being with ultrasonic echoes becomes most popular in obstetrics. However, it retains several problem that the observed echoes may include the information of the maternal body, and acoustic transfer functions are affected by the fetal movement. This paper proposes a novel monitoring system utilizing blind signal separation (BSS), which is a method for recovering a set of source signals from their mixtures without any knowledge about the mixing process.