| 摘要 |
An ultrasound scanner for scanning a medium for anomalies scattering acoustic waves, having ultrasonic transducing means positioned within scanning range of the medium; ultrasonic transmitting means coupled to the transducing means for providing a train of pulsed ultrasonic carrier signals. Each pulsed carrier signal of the train has a constant and unique frequency, the train of pulsed carrier signals together covering a range of frequencies. The transducing means is oriented to propagate the train along a path through the medium. The device further includes (a) means for repeatedly repositioning the transducing means for propagating further trains along a plurality of different paths through the medium, the plurality of different paths together defining a planar cross-section; (b) means coupled to the transducing means and responsive to the steady state phase and amplitude of the received signal to thereby define the total scatter characteristic within the planar cross-section; (c) means for calculating from the characteristic plurality of point characteristics of the acoustic property corresponding to the scatter characteristic; and (d) means for comparing each of the point characteristics with respect to one another for the anomalies.
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