A fast method for solving acoustic scattering problems in frequency bands

We present a methodology for computing efficiently scattered fields in a fr equency band. The main feature of this methodology is the construction of a series of discrete problems that differ only by their right-hand sides, ra ther than by both their left-and right-hand sides. Its key steps are (a) th e reformulation of the acoustic scattering problem in a bounded domain usin g any preferred absorbing boundary condition. (b) the characterization of t he repeated derivatives with respect to the frequency of the scattered fiel d as solutions of scattering-type problems with different source terms and boundary conditions. and (c) the reconstruction of a scattered field by eit her the Pade approximants or Wynn's algorithm. We report on several multifr equency acoustic scattering examples that illustrate the accuracy and compu tational efficiency of the proposed solution methodology. (C) 2001 Academic Press.