US Patent 7474915 Separating mixed signals containing a distorted signal

This invention provides a novel technique separating two mixed signals. The method is particularly useful for fetal electrocardiogram estimation. A maternal electrocardiogram signal recorded at the thorax area is nonlinearly mapped onto an electrocardiogram signal recorded at the abdomen using polynomial networks. The fetal electrocardiogram component is then estimated by subtracting the nonlinearly mapped maternal electrocardiogram signal from the abdominal electrocardiogram signal.