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Two-Dimensional Power Spectrum Analysis for Ultrasonic Tissue Characterization

One-dimensional (l-D) power spectrum analysis has been found useful in clinical ultrasonic tissue characterization. (1,2) To extract more information from the same basic data set of rf echo signals, analytic concepts have now been extended to two dimensions. Cross-range features not apparent from 1 -D processing techniques are highlighted using 2-D power spectrum methods. Experiments using thin wires and microspheres have shown excellent agreement with theoretical results. Preliminary results using clinical data have also demonstrated the feasibility of this technique. Possible applications include improved diagnostic capabilities for tissue typing, 2-D deconvolution for enhanced axial and lateral resolution, and other 2-D filtering operations.