This work is a study of strategies for obstacle reconstruction from multifrequency far field scattering data. We outline two strategies for obstacle reconstruction from multifrequency far field scattering data: the point source method proposed by Potthast for solving inverse scattering problems with single frequency data in the resonance region, and filtered backprojection techniques based on the physical optics approximation for high frequency scattering. Our implementation of the point source method can be viewed as a generalized filtered backprojection algorithm, the key to which is the construction of the filter used in the backprojection operator. Numerical examples indicate that the critical factor for reconstructions in multifrequency settings is the frequency dependence of the filter.

Key Words: inverse problems scattering theory image processing

SUBCATEGORY = A30

CATEGORY = 35-XX:Partial differential equations