| 摘要 |
PROBLEM TO BE SOLVED: To increase the processing speed of a circuit for executing basic algorithm of compound auto-correlation method. SOLUTION: A correlation computing means calculates the correlation between signals before and after compression of a subject tissue using an envelope signal outputted from an orthogonal detecting means. At this time, in performing correlation calculation at intervals of 1/2 wavelength, an orthogonal detecting envelope signal shifted by integral multiple of 1/2 wavelength in the axial direction is sequentially created using an orthogonal detected envelope signal, and the correlation coefficient between envelope signals before and after compression is calculated at intervals of 1/2 wavelength, whereby at the time of computing a correlation coefficient at intervals of 1/2 wavelength, repetition of orthogonal detecting operation is not needed so as to attain high-speed operation, simplify the circuit, remarkably decrease the calculation amount, and enable real-time display. COPYRIGHT: (C)2004,JPO
|
