filters

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Heart defects are among the most common birth defects and leading cause of birth defects related deaths. Most cardiac defects have some manifestation in the morphology of electocardiography and are believed to contain much more information as compared with convention sonographic methods. However due to low amplitude of fetal electrocardiogram (FECG), recorded from the maternal body surface, the application of fetal electrocardiography has been limited to heart beat analysis and invasive ECG recordings during labour.In this paper the improvement in signal processing aspects of fetal cardiography and an improved modeling and filtering of fetal ECG signal from various noise sources is done.The major challenge in the design is the removal of the noise and MECG signal from the abdominal signal .Throughout the years different methods has been adopted to remove the noise and the detection of the FECG signal. Different works has been carried out in enhancing the FECG signal. The Fetal QRS provides the information about the fetal well being and the heart rate of the fetus. The diagnosis can be done only if a proper Fetal QRS is obtained. The subtraction of an averaged pattern[1] is the simplest and oldest methods used during 1960’s now been obsolete due to the mismatching of the thoracic signal (MECG) with the thoracic component present in the abdominal signal(AECG). As the MECG is dominant and troublesome the technique fails to remove the MECG signal. Due to improper matching, instead of removal, the MECG is summed with the abdominal signal. A pure FECG is rarely obtained. The Correlation Technique is used for FECG QRS detection. Due to deficiency of proper PQRST template the method fails to detect the FECG signal. Rarely only FECG QRS ... ... middle of paper ... ... in the placement of the electrodes. In this work a multi-channel adaptive approach using affine projection algorithms are proposed. The multichannel denoising system is been implemented using adaptive filters like LMS, DLMS, BLMS, NLMS, SS, SE, SD, RLS, SWRLS, QRDRLS, FTF, AFFINE PROJECTION and Lattice filters .Adaptive filtering and independent component analysis methods are mainly gives better performance towards noise removal. The paper is organized in the way that the model of the fetal monitoring system is presented first which describes the various signals involved in the system then followed by the adopted dipole theory of heart which is been applied for generating an arbitrary number of synthetic ECG channel. Then the various adaptive denoising methods are presented and next the proposed method. Finally the results obtained by these methods are described.

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