Inverse problems for linear hyperbolic equations using mixed formulations
arXiv:1502.00114 · doi:10.1088/0266-5611/31/7/075001
Abstract
We introduce in this document a direct method allowing to solve numerically inverse type problems for linear hyperbolic equations. We first consider the reconstruction of the full solution of the wave equation posed in - a bounded subset of - from a partial distributed observation. We employ a least-squares technique and minimize the -norm of the distance from the observation to any solution. Taking the hyperbolic equation as the main constraint of the problem, the optimality conditions are reduced to a mixed formulation involving both the state to reconstruct and a Lagrange multiplier. Under usual geometric optic conditions, we show the well-posedness of this mixed formulation (in particular the inf-sup condition) and then introduce a numerical approximation based on space-time finite elements discretization. We prove the strong convergence of the approximation and then discussed several examples for and . The problem of the reconstruction of both the state and the source term is also addressed.