Apparatus for ultrasound flow mapping

Claim 1

In a device which determines the parameters of movement in a media by ultrasound pulse-echo measurements and which comprises at least one ultrasound transducer, means for exciting periodic emission of a pulsed ultrasound signal from said transducer, means for receiving ultrasound echoes which are reflected from said media back to said transducer and for processing such signals in a digital processing channel which generates and acts on discrete samples of A-line signals received from said transducer, said channel comprising, in cascade, means for suppressing signals in said A-lines which originate from fixed regions in said media, flow parameter estimation means, discriminator means, and means for displaying estimates of flow parameters; the improvement wherein: said flow parameter estimation means comprise a plurality of fractional step delay (FSD) interpolation filters each filter having an input connected to receive and interpolate an output signal from said means for suppressing and a plurality of discrete time correlator means each being connected to correlate an output of a FSD interpolation filter with a discrete sample of said A-line signals.