Real-time digital processing of Doppler ultrasound signals

Ultrasound equipment allows an early diagnosis of cardiovascular diseases to be obtained through the appropriate processing of received echo signals. In this paper a real time digital implementation of processing algorithms dedicated to investigate both the hemodynamic and mechanic properties of large human arteries is described. In particular, an FFT analysis is used to obtain the information about the blood flow, and an autocorrelation-based procedure is applied to estimate the tissue movements. Furthermore, a real-time software approach for audio processing is shown capable of generating directional Doppler signals and of reproducing them on a standard personal computer (PC). Finally, a summary of the system capabilities is presented by showing the results of application of the above procedures to common carotid artery investigation.