Application of Empirical Mode Decomposition to Remove the Wall Components in Doppler Ultrasound Signals: A Simulation Study

Doppler ultrasound blood flow analysis systems normally use a high-pass filter to remove the large, low frequency components from the vessel wall from the blood flow signal. Unfortunately, the filter also removes the low frequency Doppler signals arising from slow moving blood. In this paper, we propose to use a novel technique, called the empirical mode decomposition (EMD), to remove the wall components from the mixed signals. The EMD is used to decompose a Doppler signal into finite individual components. Then the wall components are automatically identified and removed by using a strategy. This method is applied to process the simulated Doppler signals. Compared with the results based on the tradition high-pass filter, the new approach obtains improved performance for wall removal from the mixed Doppler signals, and provide us with more accurate low blood flow