A novel algorithm for Doppler imaging based on wavelet analysis

The color Doppler method is widely used for velocity imaging, in particular in the medical application of circulatory blood flow visualization. However, the accuracy of medical systems and their observable velocity range are not always sufficient for other applications such as industry measurements. We developed a new velocity-imaging algorithm to overcome these shortcomings and confirmed the performance in airborne ultrasound. In this paper we describe the signal-processing algorithm and also refer to an experiment to acknowledge the performance. The simulation results showed that the proposed method could attain significant improvements in both accuracy and estimation range in comparison with the color Doppler method. In this paper we show the estimation results within a wide range of signal-to-noise ratios, as well as sector scan images obtained by color Doppler and the proposed method. The effects of changing the design parameters of the transmission signals are also discussed.