Quantitative Seismocrardiographic signal evaluation based on Hilbert Huang transformation

Monitoring physiological signs in noninvasive way can significantly reduce the stress impact of apparatus utilization on patients, particularly to those with a certain degree of physical limitation. However, up to now, only few devices have been proposed in the literature. One of such principle is Quantitative Seismocardiography examinations (QSCG). It is possible to determine heart rate and respiratory rate and moreover the important points (several amplitudes and time points) of QSCG signal components. Time-frequency domain methods, such as the wavelet transform, short-time discrete Fourier transform, matching pursuit, was usually used for this task, because the QSCG signal is quasi-stationary. The Hilbert-Huang transform was designed to process non-stationary signals (e.g. for Electro Encephalographic Signals). Therefore, it should be also suitable for processing QSCG signals as well. This paper presents results gained by Hilbert-Huang transform, which was used for QSCG signal evaluating. The basic information and experimental results are presented.