Tine new recursive SVD for extracting FECG from maternal abdomen

The multi-channel filtering technique is used recently to obtain Fetal ECG free of maternal ECG non-invasively fro» the electrodes placed on the eat e mal abdomen. This "inverse problem", estimating the internal source from the external measurements, is usually formulated in matrix, and solved by SVD (Singular Value Decomposition) [1]. However, the conventional SVD is difficult for clinical use, since the computations and the required memory are great, especially when the input datum matrix is large. In this paper, a new accurate recursive SVD algorithm is presented and was applied to multichannel fetal ECG signal processing. The idea is that when a set of data is inputed, the new SVD is calculated from the old SVD and the newly input data iterativejly, and the convergence is very fast. The results on real data of FECG processing are also given in this paper in order to illustrate and verify the effective of this method.