| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for coding in frequency, module and phase a digital representation, in the space field, of a ring-shaped element. SOLUTION: The method includes the steps of applying to any point of the element a polar conversion at constant angle, whereby the element is unfolded in rectangular shape; transferring, to the frequency field, any point of the converted rectangular shape by means of a Fourier transform; filtering the discrete data resulting from the transfer by means of at least one real, bidimensional, band-pass filter, oriented along the phase axis; applying a Hilbert transform to the filtering results; applying an inverse Fourier transform to the results of the Hilbert transform; and extracting phase and module information in the space field. COPYRIGHT: (C)2003,JPO |
