Patent ID: 9435905
Filing Date: 2016-09-06
CPC Classification: G01V

Claim Text:
1. A method, stored in a memory and executing on a processor, for generating a receiver-based ghost filter from recorded data, said method comprising: generating mirror data from said recorded data; transforming said recorded data and said mirror data from a time-space domain to a frequency-space domain; adding a phase coefficient to a mirror ghost filter so that the mirror ghost filter is time aligned with a ghost filter, wherein the transformed recorded data is expressed by multiplying initial primary receiver ghost-free data with the ghost filter and the transformed mirror data is expressed by multiplying the initial primary receiver ghost-free data with the mirror ghost filter; generating an initial ghost as a difference between the transformed recorded data and the initial primary receiver ghost-free data, wherein the initial primary receiver ghost-free data is calculated by jointly solving (i) a first equation that relates the transformed recorded data, the initial primary receiver ghost-free data and the ghost filter, and (ii) a second equation that relates the transformed mirror data, the initial primary receiver ghost-free data and the mirror ghost filter; generating said ghost filter by iterating through said transformed recorded data from which the initial primary receiver ghost-free data is subtracted and minimizing a sum of the initial primary receiver ghost-free data and the initial ghost multiplied by the phase coefficient to obtain a ghost delay time; calculating a final primary receiver ghost-free data associated with a current iteration based on the transformed recorded data and the ghost filter; and generating an image of a geophysical structure underground based on the final primary receiver ghost-free data.