Paper Summary
This paper proposes an improvement in the implementation of the Fourier Finite Difference (FFD) method for the one-way wave equation. Errors associated with FFD can be magnified in media with strong lateral variations in velocity. To reduce the magnitude of these errors, the reference velocity at each depth can be replaced by a velocity function which is a smooth version of the exact model. A phase-shift plus interpolation (PSPI) step is employed to compute the phase shift to this intermediate velocity. To illustrate the accuracy of the method, several migration examples are shown.