Large-scale simulations of electromagnetic and acoustic measurements using the pseudospectral time-domain (PSTD) algorithm

Recently, a pseudospectral time-domain (PSTD) algorithm was developed to simulate electromagnetic wave propagation. This technique uses the fast Fourier transform (FFT) algorithm for the spatial derivatives and uses the perfectly matched layer (PML) to eliminate the wraparound effect due to the spatial periodicity introduced by FFT. In this work, the author further analyzes this new method and compares it with the finite-difference time-domain (FDTD) and multiresolution time-domain (MRTD) methods for accuracy and efficiency. The PSTD algorithm is then applied to simulate large-scale problems for subsurface electromagnetic and acoustic measurements. For many problems encountered, since the spatial derivatives are obtained by the PSTD algorithm for continuous field components, this algorithm has a high order of accuracy in the spatial derivatives, and thus requires much fewer unknowns than the FDTD and MRTD methods. Numerical results confirm the efficacy of the PSTD method