  Discontinuous Galerkin finite element schemes exhibit attractive features for
accurate large-scale wave-propagation simulations on modern parallel
architectures. For many applications, these schemes must be coupled with
non-reflective boundary treatments to limit the size of the computational
domain without losing accuracy or computational efficiency, which remains a
challenging task. In this paper, we present a combination of a nodal
discontinuous Galerkin method with high-order absorbing boundary conditions
(HABCs) for cuboidal computational domains. Compatibility conditions are
derived for HABCs intersecting at the edges and the corners of a cuboidal
domain. We propose a GPU implementation of the computational procedure, which
results in a multidimensional solver with equations to be solved on 0D, 1D, 2D
and 3D spatial regions. Numerical results demonstrate both the accuracy and the
computational efficiency of our approach.
