| 摘要 |
In this method, only one single extrapolation phase is made for all the shooting points at each depth level, these points being previously encoded by random signals, followed by a single imaging phase, the imaging consisting in carrying out the following calculation for all the shooting points i and all the frequencies omega of the transmitted waves: <IMAGE> where the rising encoded field, U'i, denotes the convolution of the rising wave fields Ui with the random signal Ki associated with the shooting point i, that is to say U'i = Ui * Ki, where the encoded descending field D'i, denotes the convolution of the descending wave field Di with the same associated random signal Ki, that is to say D'i = Di * Ki, and where D'i denotes the complex conjugate of D'i. |
