Nonlinear separation and extract methods of fetal electrocardiography

Nonlinear separation and extract methods of fetal electrocardiography comprise two major steps: 1. separating parent population ECG component from maternal-fetal mixed electrocardiosignals to obtain preliminary estimation of fetal electrocardiosignals, which is called the first stage of separation and extract; 2. further separating some disturbances and noises from the preliminary estimation of fetal electrocardiosignals obtained from the first stage of separation and extract, thus obtaining the final estimation of the fetal electrocardiosignals, which is called the second stage of separation and extract. The patent application respectively deals with a nonlinear method in the first stage of separation and extract of fetal electrocardiography (FECG) and a nonlinear method in the second stage of separation and extract of FECG, the two methods have basically the same steps which comprise: signal preliminary processing, reconstruction of phase space, nonlinear noise reduction processing, restoration to one-dimensional signals and the like. The two methods both carry out separation and extract in response to one-way signals; as improved non-linear proposal, the methods of the invention, compared with the existing non-linear methods, are easier to obtain high separation and extract quality, high separation and extract success rate and efficiency.