Echo-Doppler ultrasonic imaging with a phased array

摘要

Abstract: This paper presents a system model and an inversion forphased array ultrasonic imaging with a moving targetwithin a stationary background. The imaging method isbased on the inversion principle that utilizes thespatial Fourier decomposition of the obtained data inthe array elements. Velocity estimation can be obtainedby examining the Doppler shift caused by a targetmoving along a scanning beam axis and Doppler spreadcaused by the same target moving normal to the beam.This process includes two filters in the reconstructedspatial domain and spatial frequency domain forseparating a moving target's signature from thestationary background. In addition, the Doppler shiftdoes not respond to the pulse propagation time butinstead responds to the scanning time which is muchslower. This slow time method makes Doppler shift andspread computable in the processing. After the velocityestimation the shifted and smeared moving targetsignature is able to be correctly and clearly imagedwith estimated velocity vector values in thereconstructed spatial domain by a phase compensation inthe spatial frequency domain. !10