A fast method for solving acoustic scattering problems in frequency bands

We present a methodology for computing efficiently scattered fields in a frequency band. The main feature of this methodology is the construction of a series of discrete problems that differ only by their right-hand sides, rather than by both their left-and right-hand sides. Its key steps are (a) the reformulation of the acoustic scattering problem in a bounded domain using any preferred absorbing boundary condition. (b) the characterization of the repeated derivatives with respect to the frequency of the scattered field as solutions of scattering-type problems with different source terms and boundary conditions. and (c) the reconstruction of a scattered field by either the Pade approximants or Wynn's algorithm. We report on several multifrequency acoustic scattering examples that illustrate the accuracy and computational efficiency of the proposed solution methodology. (C) 2001 Academic Press.