Adjoint state method for time-harmonic scattering problems with boundary perturbations

Knowing how the solution to time-harmonic wave scattering problems depends on medium properties and boundary conditions is pivotal in wave-based inverse problems, e.g. for imaging. This paper devoted exposition of a computationally efficient method, called adjoint state that allows quantify influence media properties, directly through conditions, study acoustic, electromagnetic elastic waves. Firstly, method derived general value problems. A continuous (rather than discrete) formalism adopted order highlight role terms. Then, applied systematically with impedance making use similitude between three Finally, numerical examples solved using finite element are presented demonstrate validity proposed method.