| 摘要 |
PURPOSE: To use a vector processing device at the maximum operating speed when utilizing all the effective portion of a high-speed memory by implementing the calculation of the very asymmetrical two-dimensional Fourier transformation in the 3-D TF reconstitution method. CONSTITUTION: There are N pieces of macro-sequences, and the unit duration is M.Tr respectively. When M pieces of sequences of one piece of macro- sequence are completed, the calculation of the first 2-D Fourier transformation is implemented. The calculation can be easily completed before the net macro- sequence is completed due to the number of calculation points when this 2-D Fourier transformation is conducted. The prescribed value is actually used. If the period Tr is about 50ms, one micro-sequence is continued for 400ms, i.e., 256 macro-sequences in all are continued for about 2min. But, the calculation of the 2-D Fourier transformation utilizing the high-speed memory of a vector processing device to be used is continued for about 40ms every time. That is, while n-degrees of macro-sequence is obtained, the calculation of the 2-D Fourier transformation is implemented on the result obtained on the (n-1)-degrees of macro-sequence. |
