Patent ID: 8659467
Filing Date: 2014-02-25
Classification: G01S,G01V,G06N

Abstract:
1. A method performed by a computing device for generating a contribution image frame for a transmitter based on return signals acquired by multiple receivers from a signal emitted by the transmitter at a down-track location, the receivers being at cross-track locations, the method comprising: providing a matrix of the return signals with each column representing a receiver and each row representing a fast time delay; applying a fast Fourier transform separately to each column of the matrix to generate a column transformed matrix; inserting columns of zeros into the column transformed matrix to account for under-sampling in a cross-track direction to generate a zero inserted matrix; applying a fast Fourier transform separately to each row of the zero inserted matrix to generate a row transformed matrix; multiplying the row transformed matrix by a factor to propagate the matrix to a specific depth to generate a propagated row transformed matrix; applying an inverse fast Fourier transform separately to each row of the propagated row transformed matrix to generate an inverse row transformed matrix; multiplying elements of the inverse row transformed matrix by a factor representing a field emitted by the transmitter to generate a modified inverse row transformed matrix; applying an inverse fast Fourier transform separately to each column of the modified inverse row transformed matrix to generate an inverse column transformed matrix; and creating the contribution image frame from elements of the inverse column transformed matrix.